pay royalties and make milestone payments to Bioprojet for the license of WAKIX;

First-and-only non-scheduled treatment for narcolepsy. WAKIX is the first-and-only FDA-approved treatment for narcolepsy that is not scheduled as a controlled substance by the DEA. We believe one of the most significant unmet needs is the availability of non-scheduled treatment options. In a clinical trial, pitolisant demonstrated statistically significantly lower drug liking compared to phentermine (a Schedule IV stimulant), consistent with its lack of abuse potential.

Payor Coverage: Recognizing the importanceTable of payor coverage, our field market access team has been engaging with national and regional payors over the past two plus years to educate them on the clinical data and value proposition of WAKIX. Through December 31, 2020, we have secured formulary access for approximately 80% of all insured lives (Commercial, Medicare and Medicaid) in the United States. Within these covered lives, we have observed favorable access to WAKIX subsequent to the expanded approval of WAKIX for the treatment of cataplexy in adult patients with narcolepsy in October 2020.Contents

We believe the differentiating attributes of WAKIX that have facilitated and will continue to facilitate awareness, adoption, and coverage include: (i) it is a first-in-class molecule with a novel MOA, (ii) it is the first-and-only non-scheduled treatment approved for EDS or cataplexy in adult patients with narcolepsy, (iii) it is not a stimulant, (iv) it has broad clinical utility because it can be used as monotherapy or administered concomitantly with other narcolepsy treatments, and (v) it is a once-daily oral tablet administered in the morning upon wakening.

Clinical Development In September 2021, the American Academy of WAKIX (pitolisant)

Overview

The strategy behind theSleep Medicine (AASM) updated its clinical developmentpractice guidelines on central disorders of pitolisant ishypersomnolence, which serve as evidence based on its MOA, which is thought to work by regulating histamine transmission. Pitolisant is a first-in-class molecule with a novel MOA, acting as a potent and highly selective antagonist/inverse agonist of the H₃ receptor. It activates histaminergic neurons in the brain, a neuronal system involved in the maintenance of wakefulness, attention, vigilance and cognition. Pitolisant binds to H₃ receptors on presynaptic neurons and blocks the normal negative feedback mechanismtreatment guidelines for histamine release, resulting in increased release of this wake-promoting neurotransmitter. It also functions as an inverse agonist, resulting in enhanced histamine synthesis and release from presynaptic neurons. Increased histamine available in the synapse binds to postsynaptic H₁ receptors, activating postsynaptic neurons, which stimulate wake-promoting brain regions and inhibit sleep-promoting regions of the brain.

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WAKIX® (pitolisant) Mechanism of Action

Pitolisant also stimulates the release of other wake-promoting neurotransmitters (dopamine, norepinephrine, serotonin and acetylcholine) via H₃ heteroreceptors within those neuronal systems. Importantly, pitolisant does not increase dopamine levels in the striatum, including the nucleus accumbens, which is the brain’s reward center where an increase in dopamine levels is correlated with abuse potential. This feature of pitolisant’s MOA, along with primarily working through the histaminergic system, are two of the aspects that differentiate pitolisant from all other currently approved treatments for narcolepsy.

The safety profile of pitolisant is based on pooled safety data from 22 Phase 2 or Phase 3 clinical trials conducted by Bioprojet, eight of which were in patients with narcolepsy and 14 of which were in other indications. These trials included 1,513 unique patients, of whom 1,043 received pitolisant in double-blind placebo-controlled studies, and others received pitolisant in single-blind or open-label trials. Three successful pivotal trials in narcolepsy, HARMONY 1, HARMONY 1bis, and HARMONY CTP, were completed in Europe by Bioprojet and served as the foundation for the approval of pitolisant by the EMA in 2016 for the treatment of narcolepsy in adults with or without cataplexy. Pitolisant was evaluated in a long-term safety and tolerability trial, HARMONY 3, which further supported the results observed in HARMONY 1, HARMONY 1bis, and HARMONY CTP. The data from these trials were submitted, along with data from a human abuse potential (“HAP”) trial, to the FDA as part of the NDA for WAKIX (pitolisant), which the FDA approved on August 14, 2019 for the treatment of EDS in adult patients with narcolepsy and on October 13, 2020 for the treatment of cataplexy in adult patients with narcolepsy. The table below provides an overview of the trial designs from these five clinical trials.

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Clinical Trial Highlights

The key findings from these clinical trials are as follows:

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HARMONY 1

Design

HARMONY 1 was a randomized, double-blind, placebo-controlled trial that evaluated the efficacy and safety of pitolisant in adult patients with narcolepsy on improvement in EDS over an eight-week period. The trial was conducted in the EU, and consequently was designed to include both a placebo arm and an active comparator, modafinil, which was used in doses up to 400 mg/day. HARMONY 1 consisted of 95 patients and had flexible dosing during the first three weeks of the trial, followed by five weeks of stable dosing. The maximum dose of pitolisant in this dose-to-effect trial was 35.6 mg and only 61% of the patients were titrated to this dose for the stable dosing period. Approximately 80% of the patients had a history of cataplexy.

The primary endpoint in the trial was the ESS score at final visit, adjusted for baseline, for pitolisant compared to placebo. ESS is a self-administered eight-item questionnaire scored 0 to 24 with lower scores corresponding to lower EDS. Secondary endpoints in HARMONY 1 included ESS responder rates, MWT (an objective measure of the ability to stay awake), the Sustained Attention to Response Task (“SART”) reduction in cataplexy, Clinical Global Impression of Change (“CGI-C”) for both EDS and cataplexy, the European Quality of Life Questionnaire (the “EQ-5D”), and the Patient’s Global Opinion on the Effect of Treatment Questionnaire. The main efficacy objective of the trial was to demonstrate superiority of pitolisant compared to placebo on the primary

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endpoint, while one of the secondary objectives was to explore the non-inferiority of pitolisant compared to modafinil on ESS score. It should be noted that there was no prospective plan to control for Type 1 error in this trial.

Efficacy Results

Pitolisant showed a significant reduction in the mean ESS score change from baseline to final visit at end of trial as compared to placebo (-6.0 versus -2.9, respectively) and between-group differences in ESS score were evident within the first two weeks of treatment. This resulted in a treatment effect (ESS score at final visit, adjusted for baseline, for pitolisant compared to placebo) of -3.1, which was statistically significant for pitolisant versus placebo (p=0.022). The change from baseline in ESS score for modafinil was -6.9 and, based on this score, pitolisant was not found to be non-inferior to modafinil (mean difference of 0.09, p=0.932) and the trial therefore did not meet this secondary efficacy objective. We believe there are several factors that contributed to this finding. First, 73% of the patients on modafinil in this trial were titrated up to a dose of 400 mg/day (the recommended dose of modafinil in the FDA-approved U.S. Prescribing Information (“USPI”) is 200 mg/day) while only 61% of the patients on pitolisant were titrated to the maximum pitolisant dose of 35.6 mg/day (which is the maximum approved dose in the USPI), such that a greater number of patients in the modafinil arm received the maximum effective dose than those in the pitolisant arm, raising the possibility that those subjects in the pitolisant arm could have seen greater treatment effect had they been dosed at the maximum dose available. Second, the margin of non-inferiority for the difference in the ESS scores pre-specified in the statistical analysis plan was narrow (2 points), meaning that the change in ESS score adjusted for baseline compared between pitolisant and modafinil had to have a lower 95% CI of no less than -2 points to declare pitolisant non-inferior to modafinil. The lower bound of the 95% CI of the analysis fell just outside this margin (-2.11). According to literature, however, a clinically relevant difference on the ESS ranges from 2–3 points, such that the non-inferiority margins pre-specified under the statistical analysis plan may have been too narrow. Ultimately, however, the trial results comparing pitolisant and modafinil did not impact the FDA’s findings that pitolisant was effective for improvement in EDS, and the FDA-approved label for WAKIX does not contain any data on modafinil.

Change in ESS Score Over Time

Regarding the secondary endpoints, ESS responder rates (a responder was defined as having a final ESS score < 10) were significantly greater for those patients treated with pitolisant compared to those on placebo (45.2% vs. 13.3%, respectively; p=0.013). The responder rate for patients treated with modafinil was 45.5% and the difference compared to pitolisant was not statistically significant (p=0.892). On the MWT, pitolisant treatment improved performance when compared to placebo in a statistically significant manner (p=0.044), while improvement was not significantly different compared to modafinil (p=0.173).

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With regard to other secondary endpoints, the overall pattern of response was that the findings for patients on both pitolisant and modafinil were superior to those on placebo while the responses were not significantly different for pitolisant compared to modafinil. The SART Total Score (a measure of attention) was significantly higher in the pitolisant group as compared to placebo (p=0.041), and while not significantly different from the modafinil group (p=0.363), the scores were similar (9.1 and 8.9 for pitolisant and modafinil, respectively). The CGI-C for EDS showed improvement in 56% of patients on placebo, 73% of patients on pitolisant, and 86% of patients on modafinil. Regarding the daily cataplexy rates endpoint, patients treated with pitolisant experienced a 62% reduction in the daily rate of cataplexy compared to a reduction of 8% in those on placebo and 25% in those on modafinil. Responses on the CGI-C for cataplexy were consistent with this outcome, with 29%, 45%, and 35% of patients who experienced cataplexy during the trial reporting an improvement in their cataplexy symptoms in the placebo, pitolisant, and modafinil groups, respectively. Lastly, the Patient’s Global Opinion on the Effect of Treatment Questionnaire recorded positive responses in 56% of patients in the placebo group, 81% of patients in the pitolisant group, and 86% of patients in the modafinil group.

Safety Results

Pitolisant was generally well tolerated in HARMONY 1. Sixty patients experienced a treatment emergent adverse event (“TEAE”) during the trial: 61% in the pitolisant group, 60% in the placebo group, and 70% in the modafinil group. The most commonly reported TEAE in the pitolisant treatment group was headache, reported by 35% of the patients, compared to 20% in the placebo group. Other frequently reported TEAEs in the pitolisant treatment group were insomnia, nausea and weight increase (each reported by two patients, or 6%). There were five serious adverse events during HARMONY 1 and none were considered treatment-related (two in the pitolisant group, two in the modafinil group, and one in the placebo group). There were no deaths during the trial and no significant changes in laboratory values or hemodynamic parameters (heart rate and blood pressure) from baseline to final visit in any group.

HARMONY 1bis

HARMONY 1bis was a randomized, double-blind, placebo-controlled trial that evaluated the efficacy and safety of pitolisant in adult patients with narcolepsy on improvement in EDS over an eight-week period. This trial

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was designed in accordance with recommendations from European regulators, and as such, contained both a placebo and active comparator arm. The active comparator was modafinil used in doses up to 400 mg/day. HARMONY 1bis enrolled 165 patients and had flexible dosing during the first three weeks of the trial, followed by five weeks of stable dosing. The maximum dose of pitolisant in this dose-to-effect trial was 17.8 mg and only 76% of the patients were titrated to this dose for the stable dosing period. 75% of the patients had a history of cataplexy.

The primary endpoint in the trial was the ESS score at final visit, adjusted for baseline, for pitolisant compared to placebo. Secondary endpoints included ESS responder rates, MWT, SART, reduction in cataplexy, CGI-C for both EDS and cataplexy, the EQ-5D, and the Patient’s Global Opinion on the Effect of Treatment Questionnaire. The main efficacy objective of the trial was to demonstrate superiority of pitolisant compared to placebo on the primary endpoint, while one of the secondary objectives was to explore the non-inferiority of pitolisant compared to modafinil on ESS score. It should be noted that there was no prospective plan to control for Type 1 error in this trial.

Efficacy Results

Pitolisant showed a significant reduction in the mean ESS score change from baseline to final visit as compared to placebo (-5.0 versus -2.8, respectively). This resulted in a treatment effect (ESS score at final visit, adjusted for baseline, for pitolisant compared to placebo) of -2.2 (p=0.030). The treatment effect between modafinil and pitolisant was -2.75 and, based on this score and the pre-specified statistical analysis plan, resulted in pitolisant not being non-inferior to modafinil. We believe the same factors that contributed to this result in HARMONY 1 also apply to HARMONY 1bis. In addition, in this trial, the maximum dose of pitolisant to which patients could be titrated (17.8 mg) was not the maximum labeled dose for pitolisant (which is 35.6 mg), and 24% of patients in this trial were on doses lower than 17.8 mg, which means that a substantial percentage of patients were on study drug at an amount less than the maximum approved dose in the USPI for pitolisant. In addition, modafinil was dosed up to 400 mg/day, while the recommended dose of modafinil in its USPI is 200 mg/day, which means that the respective doses of pitolisant and modafinil were not comparable.

Change in Mean ESS Score

Regarding the secondary endpoints, ESS responder rates (a responder was defined as having a final ESS score < 10 or change in ESS score ≥ 3) were significantly greater for those patients treated with pitolisant compared to those on placebo (65% vs. 34%, respectively; p=0.001). The responder rate for patients treated with modafinil

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was 77% and the difference compared to pitolisant was not statistically significant (p=0.086). On the MWT, pitolisant treatment significantly improved performance when compared to placebo (p=0.022), while improvement was not significantly different compared to modafinil (p=0.294).

With regard to other secondary endpoints, the overall pattern of response was that the findings for patients on both pitolisant and modafinil were superior to those on placebo while the responses were not significantly different for pitolisant and modafinil. The pitolisant group’s SART Total Score was significantly improved compared to placebo (p=0.043), while not significantly different compared to modafinil (p=0.407). The CGI-C for EDS showed improvement in 37% of patients on placebo, 72% of patients on pitolisant, and 78% of patients on modafinil. Responses on the CGI-C for cataplexy showed improvement for 60% of patients treated with pitolisant compared to 54% of patients on modafinil and 36% of patients on placebo. However, the difference in the reduction in the daily rate of cataplexy between pitolisant (0.32) and placebo (0.31) was not statistically significant (p=0.873). Lastly, the findings on both the EQ-5D and the Patient’s Global Opinion on the Effect of Treatment Questionnaire did not show any meaningful differences between the pitolisant and placebo treatment groups in the HARMONY 1bis trial.

Safety Results

Pitolisant was generally well tolerated in HARMONY 1bis. Seventy-seven patients experienced a TEAE during the trial: 49% in the pitolisant group, 36% in the placebo group, and 49% in the modafinil group. The most commonly reported TEAEs in the pitolisant treatment group were headache (13%), dizziness (6%), vomiting (4.5%), insomnia (4.5%), and decreased appetite (4.5%). There were no serious adverse events in the pitolisant group and there was one serious adverse event during HARMONY 1bis in the modafinil treatment group, which was not treatment-related. There were no deaths during the trial and no significant changes in laboratory values or hemodynamic parameters (heart rate and blood pressure) from baseline to final visit.

HARMONY CTP

Design

HARMONY CTP was a randomized, double-blind, placebo-controlled trial to evaluate the safety and efficacy of pitolisant on the reduction in cataplexy in adult patients with narcolepsy with frequent attacks of cataplexy over a seven-week period. HARMONY CTP consisted of 106 patients. The maximum dose of pitolisant in this dose-to-effect trial was 35.6 mg and only 65% of patients reached this dose during the stable dosing period. Both stimulants and wake-promoting agents were prohibited during the trial; only 11% of subjects were on stable doses of anti-cataplectic medications (7% in the pitolisant treatment group and 16% in patients on placebo).

The primary endpoint in HARMONY CTP was the change in the weekly rate of cataplexy (“WRC”) from baseline to the stable dosing period (Weeks 4–7) expressed as the rate ratio (change in the pitolisant group/change in the placebo group). Secondary endpoints included proportion of patients with high cataplexy rate (WRC >15), CGI-

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C for cataplexy and EDS, mean change in ESS score and percentage of ESS responders, MWT, the EQ-5D, number of days with hallucinations (as recorded in the patient diaries), and Patient’s Global Opinion on the Effect of Treatment Questionnaire. It should be noted that there was no prospective plan to control for Type 1 error in this trial.

Efficacy Results

In HARMONY CTP, pitolisant resulted in a significantly greater reduction than placebo in the WRC from baseline to the stable dosing period (Weeks 4–7), with a 75% reduction in the pitolisant group compared to a 38% reduction in the placebo group (rate ratio 0.51; 95% CI (0.44, 0.60; p<0.0001). Further, significantly fewer patients had WRC >15 at endpoint with pitolisant (6%) versus placebo (24%) (p=0.005). The clinical relevance of these findings was captured by the CGI-C related to cataplexy. Mean CGI-C score was 3.5±1.1 with placebo versus 2.6±1.1 with pitolisant. The mean reduction of the CGI-C score for pitolisant compared with placebo was -0.95 (95% CI (-1.36, -0.54); p<0.0001). Overall positive response rates on the CGI-C related to cataplexy were 67% on pitolisant and 33% on placebo.

With regard to other secondary endpoints, pitolisant demonstrated a statistically significant reduction in mean ESS score from baseline to final visit at week seven as compared to placebo (-5.4 vs. -1.9; p=0.0001) and significantly higher ESS responder rates compared to placebo (p=0.035 for Type 1 ESS responders rate and p=0.002 for Type 2 ESS responders rate; see graph below). On the CGI-C related to EDS, the mean score was 3.7 with placebo versus 2.6 with pitolisant, with a mean reduction of -0.99 (p<0.0001). Overall positive response rates on the CGI-C related to EDS were 69% on pitolisant and 24% on placebo.

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On the remainder of the secondary endpoints, pitolisant showed a statistically significant improvement on the MWT from baseline to end of trial compared to placebo. Baseline geometric means on the MWT were 4.3 minutes and 3.7 minutes for placebo and pitolisant, respectively, with final MWT values of 4.6 minutes and 7.1 minutes for placebo and pitolisant, respectively; the improvement in MWT was 78% higher with pitolisant compared to placebo (p=0.003). On the Patient’s Global Opinion on the Effect of Treatment Questionnaire, overall improvement was reported in 54% of patients on pitolisant and 26% of patients on placebo (p=0.001).

Safety Results

Pitolisant was generally well tolerated in HARMONY CTP. Thirty-five patients experienced a TEAE during the trial: 35% in the pitolisant group and 31% in the placebo group. The most commonly reported AE in the pitolisant group in HARMONY CTP was headache, which 9% of the group reported, compared to 10% in the placebo group. Other frequently reported AEs in the pitolisant group were irritability, anxiety and nausea (each reported by 3 patients, or 6%). There were no deaths or serious adverse events during HARMONY CTP and no significant changes in laboratory values or hemodynamic parameters (heart rate and blood pressure) from baseline to final trial visit in either group.

HARMONY 3

Design

HARMONY 3 was an open-label, real-world trial to assess the long-term safety and tolerability of pitolisant in the treatment of EDS in adult patients with narcolepsy, with or without cataplexy, over a one-year period (with a 5-year extension at the trial sites in France). HARMONY 3 enrolled 104 patients, 102 of whom were treated with pitolisant, and 68 completed out to one year. In HARMONY 3, 75% of patients had a history of cataplexy and 76% of patients who completed out to one year were on the maximum dose of pitolisant of 35.6 mg. For the 5-year extension phase at the trial sites in France, 50 patients were eligible to continue, of which 48 patients elected to do so and 32 of them were maintained on pitolisant out to 5 years or until the study ended.

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Efficacy Results

In the 68 patients with data at baseline and at 12 months in HARMONY 3, pitolisant reduced the mean ESS score by -4.63 over this period. The magnitude of the decrease in ESS score was larger in the subgroup of patients (n=86) who were not on pitolisant at trial entry (-5.25) as compared to the subgroup of patients (n=16) who came into the trial on pitolisant from the French Compassionate Use Program (-2.63).

ESS Score Over Time

In HARMONY 3, pitolisant also demonstrated a reduction in cataplexy and other symptoms of REM intrusion into wakefulness from baseline to month 12, showing a reduction of 65% to 76% in partial or total cataplexy attacks, respectively, out to one year. Reductions of more than 50% were also seen for other symptoms of REM dysfunction, such as hallucinations and sleep paralysis.

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Reduction in Cataplexy and Other Symptoms of REM Dysfunction with Pitolisant

Safety Results

Pitolisant was generally well tolerated in HARMONY 3. AEs observed with long-term pitolisant treatment were consistent with those observed in short-term randomized, controlled trials such as HARMONY 1, HARMONY 1bis, and HARMONY CTP. Fifty-eight of the 102 treated patients (57%) reported an aggregate of 168 TEAEs in HARMONY 3, the most common of which are shown in the table below. During the one-year trial, there were no deaths and seven patients reported 10 serious adverse events, nine of which were deemed by the investigator to be unrelated to pitolisant, and one miscarriage which was considered possibly related. No clinically significant changes in laboratory parameters, vital signs or electrocardiogram parameters were recorded over the course of the one year trial.

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Clinical HAP Trial

Design

A clinical HAP trial was conducted to evaluate the human abuse potential of pitolisant. In this trial, nondependent, recreational stimulant users able to distinguish phentermine hydrochloride (HCl; 60 mg), a CIV stimulant, from placebo in a drug discrimination test were randomized in a 4-period, double-blind, crossover design to receive single doses of pitolisant 35.6 mg (therapeutic dose), pitolisant 213.6 mg (supra-therapeutic dose), phentermine HCl 60 mg, and placebo. The primary endpoint was maximum effect (Emax) on the 100-point Drug Liking (at the moment) visual analog scale.

Results

A total of 43 subjects were enrolled and 38 completed the trial. Mean Drug Liking Emax was significantly greater for phentermine (78.7) versus pitolisant 35.6 mg (57.3; p<0.0001) and pitolisant 213.6 mg (59.0; p<0.0001). Drug Liking Emax was similar for pitolisant (both doses) and placebo (56.1) (p<0.001 for 35.6 mg versus placebo, and p=0.003 for 213.6 mg versus placebo).

Similarly, for key secondary measures of Overall Drug Liking and willingness to Take Drug Again, mean Emax scores were significantly greater for phentermine (77.4 for Overall Drug Liking and 78.7 for Take Drug Again) versus pitolisant 213.6 mg (49.3 and 44.5) and 35.6 mg (52.7 and 49.4) ( p < 0.0001 for each comparison for both doses of pitolisant compared to phentermine).

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Overall Drug Liking

Take Drug Again

In summary, in the clinical HAP trial, pitolisant demonstrated a statistically significant and clinically relevant reduction in drug liking compared to phentermine as well as an overall response profile similar to placebo. Based on these clinical data, along with data from preclinical abuse liability studies, the evidence pointed to a low risk of abuse for pitolisant, which supported the approval of WAKIX without being scheduled as a controlled substance by the DEA.

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Post-Hoc Analyses for Pitolisant

We conducted three post-hoc analyses from the database of the narcolepsy clinical trials for pitolisant, which focused on clinically relevant aspects of the product profile. The first analysis examined the time-to-onset of clinical response for pitolisant for improvement in both EDS and reduction in cataplexy based on data from 61 patients in the HARMONY 1 (pitolisant, n=31; placebo, n=30) and 105 patients in the HARMONY CTP (pitolisant, n=54; placebo, n=51) randomized, controlled clinical trials. Study medication was individually titrated to a potential maximum dose of pitolisant 35.6 mg/d and then remained stable; 61% of patients in HARMONY 1 and 65% in HARMONY CTP were titrated to the 35.6 mg dose.  Efficacy assessments included the ESS and WRC or daily rate of cataplexy. Onset of clinical response was defined as the first timepoint at which there was a statistically significant difference between pitolisant and placebo. For time-to-response for EDS using the ESS, least-squares (“LS”) mean change from baseline was significantly greater for pitolisant compared with placebo beginning at Week 2 in HARMONY 1 and Week 3 in HARMONY CTP (when patients were first able to receive the 17.8 mg dose in each study) and continued through the end of treatment. More pitolisant-treated patients were classified as treatment responders (ESS reduction of ≥ 3 points) at each post-baseline assessment than were patients in the placebo group. Pitolisant treatment resulted in a significantly greater proportion of responders versus placebo beginning at Week 3 in both studies.  In HARMONY CTP, the frequency of cataplexy attacks was significantly reduced for pitolisant compared with placebo beginning at Week 2 and continued through the end of treatment. The percentage of cataplexy responders in HARMONY CTP was significantly greater with pitolisant versus placebo beginning at Week 1 for response defined as ≥ 25% reduction in WRC and at Week 2 for response defined as ≥ 50% reduction in WRC. There was no evidence of rebound cataplexy after a one-week placebo washout phase. In summary, the onset of clinical response was observed beginning at Week 2 (HARMONY 1) or Week 3 (HARMONY CTP) for mean change in ESS score and at Week 2 (HARMONY CTP) for mean change in WRC, with further improvements observed in pitolisant-treated patients through the end of treatment. The percentage of treatment responders was significantly greater with pitolisant versus placebo beginning at Week 3 for EDS (defined as ESS score reduction ≥ 3) and at Week 2 for cataplexy (defined as ≥ 50% reduction in WRC).

Time-to-Onset of Response for EDS Based on ESS Scores in HARMONY 1

Time-to-Onset of Response for EDS Based on ESS Responder Rate (ESS reduction of ≥3 points) in HARMONY 1

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Time-to-Onset of Response for Cataplexy Based on WRC in HARMONY CTP  

Time-to-Onset of Response for Cataplexy Based on WRC Reduction ≥ 50% in HARMONY CTP

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A second post-hoc analysis evaluated the efficacy of pitolisant in patients with narcolepsy who had a high symptom burden (both EDS and cataplexy) at baseline; this analysis was based on pooled data from both the HARMONY 1 and HARMONY CTP clinical trials, in which patients could be titrated up to a maximum dose of 35.6 mg/day. The analyses included three independent patient subgroups: baseline score of ≥16 on the ESS, sleep latency of <8 minutes on MWT, and ≥15 cataplexy attacks per week. The analysis populations included 118 patients for the ESS (pitolisant, n=60; placebo, n=58), 105 for the MWT (pitolisant, n=59; placebo, n=46), and 31 for cataplexy (pitolisant, n=20; placebo, n=11). LS mean change in ESS from baseline was significantly greater for pitolisant (-6.1) compared with placebo (-2.3; p<0.001). A significantly greater percentage of pitolisant-treated patients were classified as treatment responders: for ESS score reduction >3, 69.0% in the pitolisant group versus 35.1% in the placebo group (p=0.001); for final ESS score <10, 36.2% versus 10.5%, respectively (p=0.005). Mean increase in sleep latency on the MWT was significantly greater for pitolisant (6.9 minutes) compared with placebo (3.4 minutes; p=0.017).  In patients with a high burden of cataplexy, LS mean change in the WRC was significantly greater for pitolisant (–14.5) compared with placebo (–0.1; P = 0.004). On average, the frequency of cataplexy attacks was reduced by 60.6% in the pitolisant group and <1% in the placebo group. Adverse events in the analysis populations were consistent with the known safety profile of pitolisant; headache was the most common adverse event in pitolisant-treated patients (10.0%–20.0%). These analyses demonstrated pitolisant resulted in significant improvement in patients who experience a high burden of the two most common symptoms in narcolepsy, EDS and cataplexy.

High Burden of EDS: Reduction in ESS Scores

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High Burden of EDS: Treatment Responders Based on ESS Scores

High Burden of Cataplexy: Reduction in WRC

In the third post-hoc analysis, we evaluated the cardiac safety events associated with pitolisant because cardiovascular diseases are comorbid conditions in patients with narcolepsy. Cardiovascular adverse effects are of concern with narcolepsy medications because of this comorbidity and most patients require lifelong pharmacotherapy for both narcolepsy and cardiovascular disorders. Data were obtained from a pooled analysis of the HARMONY 1 (8-week) and HARMONY CTP (7-week) clinical trials and from the 12-month, open-label

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HARMONY 3 trial. The pooled analysis included 166 patients (pitolisant, n=85; placebo, n=81). Mean change in heart rate from baseline to end-of-treatment was -0.5 beats/min with pitolisant and -0.2 beats/min with placebo (LS mean difference, -0.4; p=0.744). Mean change was also similar for pitolisant versus placebo in systolic (LS mean difference, 0.0; p=0.983) and diastolic (LS mean difference, -0.6; p=0.552) blood pressure, as was mean change in QTc interval (LS mean difference, 0.4; p=0.911). Cardiac adverse events with pitolisant included heart rate increase (n=4), right bundle branch block (n=1), sinus tachycardia (n=1), and palpitations (n=1), and with placebo included blood pressure increase (n=1). In the long-term study, mean change from baseline in QTc interval was 3.1 msec at Month 6 (n=70) and 6.1 msec at Month 12 (n=67); three patients had a post-baseline increase >60 msec but none had QTc >500 msec. Based on this analysis, no cardiac safety signals were observed during treatment with pitolisant administered up to the maximum dose of 35.6 mg and for up to one year.

Potential New Indications for Pitolisant

We are actively working on label expansion for WAKIX in narcolepsy, including indications for both EDS and cataplexy in pediatric patients. We also intend to work with the FDA toward gaining pediatric exclusivity for WAKIX. We believe that pitolisant’s ability to regulate histamine and histaminergic signaling gives it the potential to provide therapeutic benefit in other disorders that are mediated through the H₃ receptor and histamine signaling and offers a portfolio in a product opportunity with pitolisant. Histamine plays an important role in normal physiologic functioning beyond wakefulness in the areas of attention, vigilance, behavior and cognition. The presence of H₃ receptors in the hypothalamus, brainstem and cerebral cortex account for different functions, which could provide an opportunity for pitolisant to treat symptoms other than EDS in different disorders.  In addition, H₃ receptors are located mainly in the CNS as opposed to other parts of the body outside the CNS. This fact, along with pitolisant being highly selective for the H₃ receptor (as opposed to H₁ receptors, H₂ receptors and H₄ receptors), is the reason we believe in pitolisant’s unique MOA and its potential to improve symptoms in patients living with rare neurological disorders, in which impaired histamine signaling is part of the underlying pathophysiology.

Our initial plan is to seek new indications in patient populations that have symptom overlap with narcolepsy, such as EDS, while potentially pursuing opportunities in other CNS disorders of hypersomnolence. The initial clinical targets will focus on rare neurological disorders consistent with our overall strategy. We submitted an IND for PWS in October 2019 and received acknowledgement from the FDA that the proposed clinical investigation may proceed. We subsequently completed a Phase 1 PK clinical trial in pediatric patients with PWS in the fourth quarter of 2019, and initiated a long-term, open-label safety trial in these patients. In December 2020, we initiated a

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Phase 2 clinical trial to evaluate pitolisant for the treatment of EDS and other key symptoms in patients with PWS and anticipate topline results from this trial in the first half of 2022. We submitted an IND for DM at the end of 2020 and the IND opened in January 2021, after which weit, WAKIX received a “Study May Proceed” letter from the FDA in February 2021. We plan to initiate a Phase 2 clinical trial in patients with DM1 during the first half of 2021, and anticipate topline results in the second half of 2022. While conducting clinical programs to evaluate these indications, other clinical endpoints beyond EDS will be evaluated as secondary or exploratory endpoints, such as behavioral symptoms, vigilance, fatigue and cognition, to broaden the investigation of pitolisant with the hope of generating pilot data to help inform the next phase of our clinical development strategy.

Label Expansion in Narcolepsy

Cataplexy Indication

The NDA submission for WAKIX initially sought approvalstrong recommendation for the treatment of both EDSexcessive daytime sleepiness and cataplexy in adult patients with narcolepsy. Our application requesting approval

As of December 31, 2021, we continue to see growth in unique HCPs of WAKIX since it became available in November 2019. The average number of patients on WAKIX at the end of 2021 was approximately 3,800. Additionally, as of December 31, 2021, we have secured formulary access for a cataplexy indication was based on the cataplexy results from HARMONY CTPapproximately 80% of all insured lives (Commercial, Medicare and HARMONY 1. The FDA approved WAKIX for the treatment of EDS in adult patients with narcolepsy but issued a CRL for the cataplexy indication, . The FDA determined that, although we had submitted one positive clinical trial for cataplexy (HARMONY CTP), the NDA submission did not provide substantial evidence of effectiveness regarding cataplexy. The FDA therefore recommended that we conduct a second trial substantiating the results of HARMONY CTP in order to obtain approval for the cataplexy indication.

We attended a Type A post-CRL meeting with the FDA on December 12, 2019 to discuss the cataplexy indication, during which we pointed the FDA to additional analyses that were conducted in support of the HARMONY 1 cataplexy data and which were includedMedicaid) in the NDA submission. Following additional interactions with the FDA,United States. Within these covered lives, we received a general advice letter in June 2020 stating that the FDA had re-analyzed data from the HARMONY 1 clinical trial and confirmed that the cataplexy data from the HARMONY 1 clinical trial supported a statistically significant reduction in the daily rate of cataplexy in the pitolisant group when compared with the placebo group. As a result, the FDA recommended we submit a complete response resubmission in pursuit of the adult cataplexy indication forhave observed favorable access to WAKIX which we sentsubsequent to the FDA in August 2020. On October 13, 2020 we received regulatoryexpanded approval forof WAKIX for the treatment of cataplexy in adult patients with narcolepsy.narcolepsy in October 2020.

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Table of 2021 in pursuit of pediatric indications for both EDS and cataplexy. Our current plan is to evaluate approximately 90 to 100 pediatric patients, ages six to up to 18, to assess the safety and efficacy of pitolisant in pediatric narcolepsy patients on improvement in both EDS and reduction in cataplexy.Contents

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Prader-Willi Syndrome

PWS is a rare genetic disorder caused by a loss of function of specific genes on chromosome 15 resulting in hypothalamic dysfunction and decreased levels of orexin/hypocretin in some patients with PWS. The hypothalamus controls both sleep-wake states and hunger-satiety; therefore, two of the main symptoms in patients with PWS are EDS and hyperphagia. Other features include low muscle tone, short stature, behavioral problems and cognitive impairment. It is estimated that approximately one in 15,000 to 20,000 people in the United States suffer from PWS, and over half of those suffering from PWS also have reported or experienced EDS. We submittedopened an IND for pitolisant for the treatment of PWS in OctoberNovember 2019, and received acknowledgement from the FDA that the proposed clinical investigation may proceed. We subsequently completed a Phase 1 PK clinical trial in pediatric patients with PWS in the fourth quarterDecember of 2019, andthen initiated a long-term, open-label safety trial in these patients.those patients who participated in the Phase 1 PK trial. In December 2020, we initiated a Phase 2 proof of concept clinical trial to evaluate pitolisant for the treatment of EDS and other key symptoms in patients with PWS, including behavioral symptoms and anticipate toplinecognitive impairment. Topline results from this clinical POC trial are anticipated in the firstsecond half of 2022.2022

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PWS poses a heavy burden for both patients and caregivers and there are few therapeutic options available and no FDA-approved treatments for EDS in patients with PWS. Clinical development programs in PWS have focused on hyperphagia, with no other programs focusing on EDS or cognitive function. EDS is thought to have a negative effect on behavior and cognitive function and could exacerbate these symptoms in patients with PWS. In addition, impaired histamine signaling in the brain can contribute to behavioral symptoms and impaired cognition. We believe there is a compelling opportunity for the mechanism of action of pitolisant to impact the EDS component of this disorder as well as other symptoms, such as behavioral issues and cognitive impairment.

We have collaborated with the Foundation for Prader-Willi Research (the “FPWR”) to advance our clinical program and underscore our commitment to this patient population. We are members of the FPWR Clinical Trials Consortium and are working with members of its Scientific Advisory Board to gain their insights for our development program. Progress to date includes (i) opening an IND for PWS in October 2019, (ii) the completion of a Phase 1 PK trial in patients with PWS in the fourth quarter ofDecember 2019, with patients actively rolling over into an open-label, long-term safety trial, (iii) the submission of a Phase 2 proof of concept clinical protocol to the FDA for review and comment, and (iv) initiation of a Phase 2 clinical POC trial in December 2020.

The Phase 2 clinical POC trial is a randomized, double-blind, placebo-controlled trial to assess the safety and efficacy of pitolisant in patients with PWS ages 6 to 65. An estimated 60 to 70 patients will be enrolled at approximately 1015 sites across the United States. Patients will be randomized to low-dose pitolisant, high-dose pitolisant or placebo in a 1:1:1 treatment ratio and titrated over three weeks up to their randomized dose, followed by eight weeks of stable dosing. The primary trial objective is to assess for improvement in EDS as measured by the Multiple Sleep Latency Test.both subjective and objective scales. Secondary endpoints include several behavioral symptom scales as well as specific measures of cognitive function using validated computer-based assessments. Clinician global impression of disease severity, caregiver global impression of EDS severity, and overall caregiver burden will be measured. Exploratory endpoints include the effect of pitolisant on hyperphagia and measurements of ghrelin levels. Patients who complete the trial will be eligible to participate in an open-label extension phase to assess the long-term safety and effectiveness of pitolisant in patients with PWS, which will run throughout the duration of the PWS development program.

Myotonic Dystrophy

DM is a rare, multi-system genetic disease that affects the neuromuscular system as well as several other systems. The primary symptom in patients with DM is myotonia, which is an impairment in the ability of muscles to relax; progressive muscle weakness is another prominent symptom of the disorder. It is inherited in an autosomal dominant pattern and there are two main types: DM1 and DM2. The underlying cause of DM1 is a mutation in the DMPK gene on chromosome 19. DM1 is the most common form of adult-onset muscular dystrophy and affects as many as 140,000160,000 patients in the United States. EDS and fatigue are hallmark clinical characteristics in the majority of patients with DM1 and are referred to as the most frequent non-muscular symptoms in patients with DM1. EDS and fatigue occur in approximately 80% to 90% of patients with DM1. Cognitive impairment is also a prominent symptom in patients with DM1 and all of these symptoms are thought to be mediated through H3 receptors and histaminergic pathways located throughout the CNS. DM2 is not as common as DM1 with an estimated prevalence of between 3,000 and 29,000 patients in the United States. The underlying cause of DM2 is a mutation in the CBNP gene on chromosome 3. Patients with DM1 and DM2 share similar phenotypes but disease onset is later in patients with DM2 and symptoms tend to be milder. There are currently no FDA-approved treatments for patients with DM, which represents a significant unmet medical need.

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The therapeutic application of pitolisant may provide benefits across the key symptoms of EDS and fatigue which are often among the chief complaints of patients with DM. In a survey of 451 DM1 patients, daytime sleepiness and fatigue were second only to muscle weakness in symptom prevalence and impact. Our clinical program will beis designed to demonstrate effect on measures of EDS and fatigue, as well as assess performance related to cognitive function, such as attention, vigilance and working memory. Progress to date includes working with key opinion leaders to develop the scientific rationale for the investigation of pitolisant in patients with DM, development of a Phase 2 clinical protocol, submission of an IND at the end of 2020, the opening of an IND in January 2021, and receiptinitiation of a “Study May Proceed” letter from the FDA in February 2021. We plan to initiate a Phase 2 clinical trial in adult patients with DM1 in the first halfJune of 2021.

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The proposed Phase 2 clinical trial is a randomized, double-blind, placebo-controlled trial to assess the safety and efficacy of pitolisant in adult patients with DMDM1 ages 18 to 65. An estimated 130 to 140 patients will be enrolled at approximately 1420 to 1622 sites across the United States.States and Canada. Patients will be randomized to low-dose pitolisant, high-dose pitolisant, or placebo in a 1:1:1 treatment ratio and titrated over three weeks up to their randomized dose, followed by eight weeks of stable dosing. The primary trial objective is to assess for improvement in EDS as measured by the MWT and the ESS. Secondary endpoints include assessments of fatigue as well as specific measures of cognitive function using validated computer-based assessments. Clinician and patient global impression of disease severity using the CGI-S and PGI-S, respectively, will be measured as well as disease-specific patient assessments of overall disease burden. Plasma samples will be collected to generate pharmacokinetic data and a PK/PD analysis will be performed. Patients who complete the trial will be eligible to participate in an open-label extension phase to assess the long-term safety and effectiveness of pitolisant in adult patients with DM,DM1, which will run throughout the duration of the DM development program.

Other Potential IndicationsExpand our pipeline through acquisition of additional assets

The next phase of clinical development for pitolisant will be guided by the signals generated from the clinical trials described aboveHBS-102

On August 4, 2021, we acquired HBS102 along with intellectual property and other potential trials in patients with PWSassets related to the development, manufacture, and DM. If we observe favorable results in these trials on the symptoms of fatigue and cognitive dysfunction, we plan to investigate pitolisant in other rare neurological patient populations in which these symptoms are a prominent partcommercialization of the disease processCompound from ConSynance Therapeutics, Inc. We acquired full development and result in significant impact on daily functioning. Furthermore, we believe opportunities exist in adjacent disorders to narcolepsy, including other CNS disorders of hypersomnolence, which could lead to additional potential new indications.

Manufacturing, Supply and Distribution

We sell WAKIX to our customers, a limited number of specialty distributors, that, in turn, distribute WAKIX to patients.

We have secured a commercial drug supply to support the launch of WAKIX in the United States. Although we do not currently own or operate facilities for product manufacturing, storage and distribution, or testing,commercialization rights globally, but we have contracted directly with third partiesprovided a grant-back license to ConSynance for eachthe development and commercialization of these functions.

Manufacturingthe Compound in Greater China. HBS-102 is subject to extensive regulation that imposes various procedural and documentation requirements that govern record keeping, manufacturing processes and controls, personnel, quality control and quality assurance, and more. Our systems and our contractors are required to be in compliance with these regulations, and compliance is assessed regularly through monitoring of performancea Melanin-concentrating hormone receptor 1 (MCHR1) antagonist and a formal audit program.potential first-in-class molecule with a novel mechanism of action. We are currently assessing potential clinical targets for HBS-102 which will inform our development strategy going forward.

Our current supply chain for WAKIX involve several manufacturers that specialize in specific operations of the manufacturing process, specifically, intermediate and starting material manufacturing, drug substance manufacturing, and drug product manufacturing, labeling and secondary packaging, and distribution services:

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Competition

Our industry is highly competitive and subject to rapid and significant change as research provides a deeper understanding of rare neurological disorders, including narcolepsy, and as new therapies are developed. We face potential competition from multiple sources, including large pharmaceutical, biotechnology and specialty pharmaceutical companies. The key competitive factors affecting the success of WAKIX, and any other product candidates that we develop, if approved, are likely to be efficacy, safety, convenience, price, the level of generic competition and the availability of reimbursement from government and other third-party payors.

WAKIX competes with currently FDA-approved products for the treatment of EDS or cataplexy in adult patients with narcolepsy, all of which are controlled substances. Jazz Pharmaceuticals’ Xyrem (sodium oxybate) is an FDA-approved product for the treatment of cataplexy or EDS in patients 7 years of age and older with narcolepsy Xyrem is a Schedule III controlled substance available only through a restricted access REMS program. Xywav, a lower sodium formulation of Xyrem, was approved in July 2020, (became commercially available in November 2020), and is also a Schedule III controlled substance subject to the same restricted access REMS program as Xyrem. Provigil and Nuvigil, which are Schedule IV WPAs, and stimulants such as methylphenidate and amphetamine (both Schedule II controlled substances), are approved for the treatment of EDS in narcolepsy. Anti-depressants and certain other agents are sometimes used off-label for the treatment of cataplexy in narcolepsy. Jazz Pharmaceuticals’ Sunosi (solriamfetol) was approved by the FDA in March 2019 and launched in July 2019. Sunosi (solriamfetol) is a Schedule IV controlled substance and is indicated to improve wakefulness in adult patients with EDS associated with narcolepsy or obstructive sleep apnea. It is not indicated for cataplexy in patients with narcolepsy. Additionally, Avadel Pharmaceuticals is working on a once nightly formulation version of sodium oxybate, with approval expected in 20212023 or beyond, and Xyrem is expected to go generic in 2023.2023 or earlier depending upon the achievement of certain milestones in their agreement with generic filer Hikma Pharmaceuticals. Beyond 2023, there are other potential future competitive products in development, including Axsome Therapeutics’sTherapeutics’ AXS-12 (reboxetine) product candidate and Takeda’s TAK-925/994994/861 (orexin 2 receptor agonist) product candidates.

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We believe WAKIX offers a differentiated product profile that is competitive with each of the products listed above, some of which are only approved for EDS while others (Xyrem and Xywav) are approved for the treatment of both EDS or cataplexy in patients with narcolepsy. It should be noted that WAKIX has not been compared with these products in head-to-head clinical trials, but its non-scheduled status represents a distinct competitive advantage relative to those same products. Additionally, WAKIX is priced lower than Xyrem and Xywav, which we believe is a competitive advantage for WAKIX and may contribute to third-party payor preferences for WAKIX relative to Xyrem and Xywav. Conversely, WAKIX is priced higher than other competitors such as Provigil (modafinil), Nuvigil, Sunosi (armodafinil) and certain generic competitors, such as methylphenidate and amphetamine, which may contribute to third-party payor preferences for those lower-priced treatment options relative to WAKIX.

Manufacturing, Supply and Distribution

We sell WAKIX to our customers, a limited number of specialty distributors, that, in turn, distribute WAKIX to patients.

We have secured a commercial drug supply to support the launch of WAKIX in the United States. Although we do not currently own or operate facilities for product manufacturing, storage and distribution, or testing, we have contracted directly with third parties for each of these functions.

Manufacturing is subject to extensive regulation that imposes various procedural and documentation requirements that govern record keeping, manufacturing processes and controls, personnel, quality control and quality assurance, and more. Our systems and our contractors are required to be in compliance with these regulations, and compliance is assessed regularly through monitoring of performance and a formal audit program.

Our current supply chain for WAKIX involve several manufacturers that specialize in specific operations of the manufacturing process, specifically, intermediate and starting material manufacturing, drug substance manufacturing, and drug product manufacturing, labeling and secondary packaging, and distribution services:

Customers and Suppliers

We depend on a few major customers. For the year ended December 31, 2020,2021, three customers accounted for 100% of gross product revenues; Caremark LLC accounted for 40%36% of gross product revenues; PANTHERx Specialty Pharmacy LLC accounted for 33%35% of gross product revenues; and Accredo Health Group, Inc. accounted for 27%29% of gross product revenues. We also depend on a single source supplier for our product, product candidates and active pharmaceutical ingredient.

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Strategic Agreement

License and Commercialization Agreement with Bioprojet

On

In July 28, 2017, we and Bioprojet entered into the Bioprojet License Agreement. Bioprojet granted to us an exclusive, sublicensable license to commercialize, in the United States and its territories, commonwealths, and protectorates, including Puerto Rico, a product containing pitolisant currently known as WAKIX for narcolepsy, obstructive sleep apnea, idiopathic hypersomnia, Parkinson’s disease, and any other indication agreed upon by the parties (whichwhich currently include PWS and DM), or DM (“the field,field”), as well as rights to related patent rights, know-how, trademarks, trade dress, regulatory filings and approvals (the “Bioprojet Assets”). Bioprojet also granted us a co-

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exclusiveco-exclusive (with Bioprojet), sublicensable license to Bioprojet Assets to clinically develop and register the pitolisant product in the field in the United States. Bioprojet retains the right to manufacture the product in the United States, and to develop outside the United States and commercialize other products that contain pitolisant as an active ingredient anywhere in the world. Bioprojet also granted us an exclusive license to use certain trademarks and trade names in connection with the commercialization of the product under the Bioprojet License Agreement. Under the Bioprojet License Agreement, we cannot, directly or indirectly, develop, market, sell, promote or file an NDA with respect to any product that would compete with pitolisant in the field.

Under the Bioprojet License Agreement, Bioprojet is responsible for conducting all preclinical studies and clinical trials necessary for achieving and maintaining regulatory approval in the United States for narcolepsy and cataplexy indications, including all costs and expenses. We are responsible for all other costs associated with other development and regulatory activities, unless Bioprojet otherwise agrees to participate in funding such activities. Bioprojet was responsible for filing, with our participation, the initial new drug application for the product with the FDA and Bioprojet did transfer such application to us upon approval by the FDA in accordance with the terms of the Bioprojet License Agreement.

Upon approval by the FDA, we were required under the Bioprojet License Agreement to promptly launch the product and use commercially reasonable efforts to commercialize the approved products in the United States in the field for each approved indication. In addition, we are required to deploy a number of sales representatives and spend an amount of expenditure, each as agreed upon in a commercialization plan.

Under the Bioprojet License Agreement, Bioprojet has the right and authority to prepare, file, prosecute and maintain all Bioprojet patents on a worldwide basis at its own cost. Bioprojet shall keep us informed of the course of prosecution and other proceedings in the United States. We have the first right to enforce the licensed patent rights with respect to any infringing products in the United States. If we do not bring an action to enforce such patents against infringing activities that involve such infringing products, Bioprojet has the right to bring such action.

We paid Bioprojet an initial license fee of $150.0 million, a milestone payment of $50.0 million upon FDA acceptance of the NDA in February 2019, and a milestone payment of $75.0 million plus an additionadditional $2.0 million fee for approval of the NDA in November 2019. Upon the Cataplexy Milestone Trigger Date, we became obligated to make the Cataplexy Milestone Payment to Bioprojet pursuant to the terms of the Bioprojet License Agreement. Subsequently, in October 2020, we made a payment to Bioprojet of $2.0 million to extend the Cataplexy Milestone Payment due date to within 90 days of the Cataplexy Milestone Trigger Date. OnIn January 6, 2021, we made the $100.0 million Cataplexy Milestone Payment in full to Bioprojet. In addition, we are subject to a milestone payment of $40.0 million upon the attainment of aggregate net sales of WAKIX in the United States of $500.0 million subsequent to the date of NDA approval by the FDA pursuant to the Bioprojet License Agreement. We attained this milestone subsequent to December 31, 2021 and expect to make the milestone payment in March 2022. We agreed to pay royalties on the product at tiered royalty rates of 13% to 24% based on annual total net sales during the period commencing on first commercial sale of the product and ending on the latest of 10 years from first commercial sale of the product, expiration of all regulatory exclusivity, or expiration of the last Bioprojet patent covering the product. Such royalty payments are subject to reductions based on royalties paid to any third party in order for us to commercialize the product. We also agreed to pay royalties in consideration for a trademark license at a rate of 3% of net sales for 20 years after first commercial sale of the product. We further agreed to pay minimum royalties during the third through tenth year of the Bioprojet License Agreement if the product is approved for narcolepsy to the extent such minimum royalties exceed the royalties payable as described above, which minimum amounts were calculated based on sales materially below our sales forecast.

The Bioprojet License Agreement will continue until the expiration of the obligation to pay royalties with respect to the product. We and Bioprojet may each terminate the Bioprojet License Agreement for a material breach by the other party that remains uncured for 90 days. Bioprojet may terminate the Bioprojet License Agreement in its entirety if we or our

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sublicensees challenge the licensed patents. In addition, we and Bioprojet have the right to terminate the Bioprojet License Agreement upon the other party’s insolvency.

Intellectual Property

Intellectual property, including patents, trade secrets, trademarks and copyrights, is important to our business. Our commercial success depends in part on our ability to obtain and maintain proprietary intellectual property protection for our WAKIX product and potential future pitolisant-based products, as well as for future

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product candidates and novel discoveries, product development technologies, and know-how. Our commercial success also depends in part on our ability to operate without infringing on the proprietary rights of others and to prevent others from infringing our proprietary rights. Our policy is to develop and maintain protection of our proprietary position by, among other methods, licensing or filing U.S. and foreign patents and applications relating to our technology, inventions, and improvements that are important to the development and implementation of our business.

Our WAKIX patent portfolio comprisesis comprised of three U.S. patents exclusively licensed to us from Bioprojet. One U.S. patent, No. 8,207,197, has claims directed to a polymorph, i.e. a specific crystalline form, of pitolisant and, methods for preparing that polymorph of pitolisant, which is expected to expire in February 2029 without taking into consideration any possible patent term extension. A second U.S. patent, No. 8,486,947, has claims directed to methods of treating excessive daytime sleepiness by administering pitolisant, which is expected to expire in September 2029 without taking into consideration any possible patent term extension. With all applicable patent term adjustments available andextension granted to us, we believe the term of the last-to-expire pitolisant-related patent in our portfolio extendswill extend to February 2030 or September 2029. We may receive additional2030, depending on which patent term based on thewe elect for patent term extension as described below.

Our HBS-102 patent portfolio comprises three patent families.  The first patent family includes a U.S. patent No. 8,637,501, which has claims certain melanin-concentrating hormone (MCH-1) receptor antagonists as compositions of matter, as well as methods of making the antagonists, and methods of use for treating obesity, anxiety, and depression, and processes for preparing the compounds, which is expected to expire in April 2031 without taking into consideration any possible patent term extension.  A second patent family comprises three issued U.S. patents (Nos. 8,716,308; 9,296,743, and 9,650,378), and issued patents in Australia, Brazil, Canada, China, Germany, Spain, France, the United Kingdom, Israel, Italy, Japan, Korea, Mexico, and New Zealand.  The patents have claims directed to certain human MCH-1 receptor-selective antagonists as compositions of matter, and are expected to expire in June 2031 (the ‘308 patent) and January 2029 (the ‘743 and ‘378 patents, as well as the international patents).  The third patent family comprises a pending PCT application (WO2021/142395) and has claims directed to therapeutic combinations or formulations of drugs comprising triple monoamine reuptake inhibitors, MCH receptor 1 (MCHR1) antagonists, and diazoxide, and methods of treating or preventing hyperphagia, moderate to severe binge eating disorder, bulimia nervosa, and management of obesity.

The term of individual patents in our portfolio depends upon the legal term of patents in the countries in which they are obtained. In the United States, the patent term is 20 years from the earliest date of filing a non-provisional patent application. The term of a U.S. patent may be eligible for patent term adjustment, which permits patent term restoration as compensation for delays incurred at the U.S. Patent and Trademark Office (the “USPTO”) during the patent prosecution process. In addition, for patents that cover an FDA-approved drug, the Drug Price Competition and Patent Term Restoration Act of 1984 (the “Hatch-Waxman Act”) permits a patent term extension of up to five years beyond the expiration of the patent. While the length of the patent term extension is related to the length of time the drug is under regulatory review, patent term extension cannot extend the remaining term of a patent beyond a total of 14 years from the date of product approval, and only one patent per approved drug may be extended under the Hatch-Waxman Act. We have applied for patent term extension on two patents covering pitolisant (the ‘197 and ‘947 patents referenced above), only one of which will receive patent term extension, if at all. While we have received confirmation fromFDA has advised the USPTO that the patents are eligiblerelevant regulatory review period for WAKIX was 505 days and, based on that information, we estimate the length of such patent term extension thereto be 374 days. There is no guarantee that the applicable authorities, including the USPTO and the FDA, will agree with our assessment of whether such extension should be granted. We estimate the length of such extension to be 389 days; however, the USPTO, in conjunction with the FDA, will calculate the length of such extension and there is no guarantee that their calculationdetermination will align with our estimate.

The patent positions of companies like ours are generally uncertain and involve complex legal and factual questions. Changes in either the patent laws or their interpretation in the United States may diminish our ability to protect our technology or product candidates and could affect the value of such intellectual property. In particular, our ability to stop third parties from making, using, selling, offering to sell or importing products that infringe our intellectual property will depend in part on our success in enforcing patent claims that cover our technology, inventions and improvements. We cannot guarantee that patents will be granted with respect to any patent applications we may file in the future, nor can we be sure that any patents that may be granted to us in the future will be commercially useful in protecting our products, the methods of use or

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manufacture of those products. Moreover, issued patents do not guarantee the right to practice our technology in relation to the commercialization of our products. Issued patents only allow us to block potential competitors from practicing the claimed inventions of the issued patents.

Further, patents and other intellectual property rights in the pharmaceutical and biotechnology space are evolving and involve many risks and uncertainties. For example, third parties may have blocking patents that could be used to prevent us from commercializing our product candidates and practicing our proprietary technology, and our issued patents may be challenged, invalidated or circumvented, which could limit our ability to stop competitors from marketing related products or could limit the term of patent protection that otherwise may exist for our product candidates. In addition, the scope of the rights granted under any issued patents may not provide us with protection or competitive advantages against competitors with similar technology. Furthermore, our competitors may independently develop similar technologies that are outside the scope of the rights granted under any issued patents. For these reasons, we may face competition with respect to our product candidates. Moreover, because of the extensive time required for development, testing and regulatory review of a potential product, it is possible that,

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before any particular product candidate can be commercialized, any patent protection for such product may expire or remain in force for only a short period following commercialization, thereby reducing the commercial advantage the patent provides.

We and/or our licensor also rely on protections under trade secret laws, and seek to protect and maintain the confidentiality of proprietary information to protect aspects of our business that are not amenable to, or that we do not consider appropriate for, patent protection. Our trade secrets include, for example, certain program specific synthesis, formulations, patient selection strategies and certain aspects of our research. It is our policy to require our employees, consultants, outside scientific collaborators, sponsored researchers and other advisors to execute confidentiality agreements upon the commencement of employment or consulting relationships with us, and for employees and consultants to enter into invention assignment agreements with us. These agreements provide that all confidential information developed or made known to the individual during the course of the individual’s relationship with us is to be kept confidential and not disclosed to third parties except in specific circumstances. Where applicable, the agreements provide that all inventions to which the individual contributed as an inventor shall be assigned to us, and as such, will become our property. There can be no assurance, however, that these agreements will provide meaningful protection or adequate remedies for our trade secrets in the event of unauthorized use or disclosure of such information.

Further, we have in-licensed from Bioprojet the registered trademark product name “WAKIX” in the United States. We also have registered trademark protection in the United States for “KNOW NARCOLEPSY” as well as our brand and logo “HB,” “HB HARMONY BIOSCIENCES” and “HARMONY BIOSCIENCES.” We also have trademark applications pending with the U.S. Patent and Trademark Office for “REM AT THE WRONG TIME” and “NON-REM AT THE WRONG TIME.”

Government Regulation

The FDA and comparable regulatory authorities in state and local jurisdictions and in other countries impose substantial and burdensome requirements upon companies involved in the clinical development, manufacture, marketing and distribution of drugs, such as those we are developing. These agencies and other federal, state and local entities regulate, among other things, the research and development, testing, manufacture, quality control, safety, effectiveness, labeling, storage, record keeping, approval, advertising and promotion, distribution, post-approval monitoring and reporting, sampling and export and import of our product candidates.

U.S. Drug Development Process

In the United States, the FDA regulates drugs under the Federal Food, Drug, and Cosmetic Act (the “FDCA”) and its implementing regulations. The process of obtaining regulatory approvals and the subsequent compliance with appropriate federal, state, local and foreign statutes and regulations requires the expenditure of substantial time and financial resources. Failure to comply with the applicable U.S. requirements at any time during the product development process, approval process or after approval, may subject an applicant to a variety of administrative or judicial sanctions, such as the FDA’s refusal to approve pending NDAs, withdrawal of an approval, imposition of a clinical hold, issuance of warning letters, product recalls, product seizures, total or partial suspension of production or distribution, injunctions, fines, refusals of government contracts, restitution, disgorgement or civil or criminal penalties.

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The process required by the FDA before a drug may be marketed in the United States generally involves the following:

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If our relationships do not result in the successful discovery, development and commercialization of products or if a third party terminates its agreement with us, we may not receive any future research funding or milestone or royalty payments under the collaboration. If we do not receive the funding we expect under any third party agreements we enter into, our development of pitolisant or any future product candidates could be delayed and we may need additional resources. Additionally, if any third party terminates its agreement with us, we may find it more difficult to attract new collaborators and our perception in the business and financial communities could be adversely affected.

Relationships are complex and time-consuming to negotiate and document. In addition, there have been a significant number of recent business combinations among large pharmaceutical companies that have resulted in a reduced number of future collaborators. We face significant competition in seeking appropriate collaborators. Our ability to reach a definitive agreement for a collaboration will depend, among other things, upon our assessment of the collaborator’s resources and expertise, the terms and conditions of the proposed collaboration and the proposed collaborator’s evaluation of a number of factors. If we are unable to reach agreements with suitable third parties on a timely basis, on acceptable terms, or at all, we may have to curtail the development of a product candidate, reduce or delay its development program or one or more of our other development programs, delay its potential commercialization or reduce the scope of any sales or marketing activities, or increase our expenditures and undertake development or commercialization activities at our own

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expense. If we elect to increase our expenditures to fund development or commercialization activities on our own, we may need to obtain additional expertise and additional capital, which may not be available to us on acceptable terms, or at all. If we fail to enter into relationships or do not have sufficient funds or expertise to undertake the necessary development and commercialization activities, we may not be able to further develop our product candidates, bring them to market and generate revenue from sales of drugs or continue to develop our technology, and our business may be materially and adversely affected.

We expect to rely on third parties to conduct our clinical trials for pitolisant and any future product candidate that we decide to develop. If these third parties do not successfully carry out their contractual duties, meet expected deadlines or comply with regulatory requirements, we may not be able to obtain regulatory approval of or commercialize any potential product candidates on a timely basis or at all.

We will continue to rely upon third parties, including independent investigators, to conduct preclinical studies or clinical trials under agreements with universities, medical institutions, CROs, strategic partners and others. We expect to have to negotiate budgets and contracts with CROs and study or trial sites, which may result in delays to our development timelines and increased costs.

We will have to rely heavily on third parties over the course of our preclinical studies and clinical trials and, as a result, will have limited control over the clinical investigators and limited visibility into their day-to-day activities, including with respect to their compliance with the approved clinical protocol and regulatory requirements. Nevertheless, we are responsible for ensuring that each of our preclinical studies and clinical trials is conducted in accordance with the applicable protocol, legal and regulatory requirements and scientific standards, and our reliance on third parties does not relieve us of our regulatory responsibilities. We and these third parties are required to comply with GCP requirements for clinical trials, which are regulations and guidelines enforced by the FDA and comparable foreign regulatory authorities for product candidates in clinical development.

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Regulatory authorities enforce these GCP requirements through periodic inspections of study or trial sponsors, clinical investigators and trial sites. If we or any of these third parties fail to comply with applicable GCP requirements, the clinical data generated in our clinical trials may be deemed unreliable and the FDA or comparable foreign regulatory authorities may require us to suspend or terminate these clinical trials or perform additional clinical trials before approving our marketing applications. We cannot be certain that, upon inspection, such regulatory authorities will determine that any of our clinical trials comply with the GCP or other applicable requirements. In addition, our clinical trials must be conducted with drug products produced under cGMP requirements and may require a large number of patients. Our failure or any failure by these third parties to comply with these regulations, which would delay the regulatory approval or commercialization process. Moreover, our business may be implicated if any of these third parties violates federal or state laws or regulations including fraud and abuse or false claims laws and regulations or healthcare privacy and security laws.

Any parties conducting our future clinical trials, if any, generally will not be our employees and, except for remedies that may be available to us under our agreements with the third parties conducting such clinical trials, if any, we cannot control whether or not they devote sufficient time and resources to our ongoing preclinical and clinical programs. These third parties may also have relationships with other commercial entities, including our competitors, for whom they may also be conducting clinical trials or other product development activities, which could affect their performance on our behalf. If these third parties do not successfully carry out their contractual duties or obligations or meet expected deadlines, if they need to be replaced or if the quality or accuracy of the clinical data they obtain is compromised due to the failure to adhere to our clinical protocols or regulatory requirements or for other reasons, our clinical trials may be extended, delayed or terminated and we may not be able to complete development of, obtain regulatory approval of or successfully commercialize our current and future product candidates. As a result, our financial results and the commercial prospects for our current and future product candidates would be harmed, our costs could increase and our ability to generate revenue could be delayed.

If any of our relationships with these third-party CROs or others terminate, we may not be able to enter into contractual and other arrangements with alternative CROs or other third parties in a timely manner to meet projected clinical development deadlines or to do so on commercially reasonable terms. Switching or adding additional CROs involves additional cost and requires management time and focus. In addition, there is a natural transition period when a new CRO begins work. As a result, delays may occur, which can materially affect our ability to meet our desired clinical development timelines. Though we carefully manage our relationships with our CROs, there can be no assurance that we will not

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encounter similar challenges or delays in the future or that these delays or challenges will not have a material adverse impact on our business, financial condition and prospects.

If we experience delays in meeting or fail to meet the regulatory requirements for commercialization of our current or future potential product candidates, the commercial prospects for our product candidates may be harmed and our ability to generate revenues will be materially impaired.

We rely completely on third parties to manufacture and distribute our supply of WAKIX, including certain sole-source suppliers and manufacturers, and intend to rely on third parties to manufacture and distribute any future product candidates.

We do not currently have, nor do we plan to acquire, the infrastructure or capability to manufacture or distribute commercial quantities of WAKIX. Our ability to commercially supply WAKIX depends, in part, on the ability of third-party manufacturers to supply and manufacture the raw materials, API and other important components related to the manufacture of WAKIX. We also rely on third parties to package the finished product. These third-party manufacturers have limited experience manufacturing the raw materials and API for WAKIX to be supplied to patients in the United States. Prior to the approval of WAKIX, we experienced minor issues related to product specifications and other minor delays in supply related to our third-party suppliers and manufacturers. While we continue to work with our third-party suppliers and manufacturers to optimize the manufacturing process for WAKIX and will work to optimize the manufacturing process for any future product candidates, we cannot guarantee that even minor changes in the process will result in products that are safe and, where applicable, effective. If we fail to develop and maintain supply relationships with these third parties, we may be unable to continue to successfully commercialize WAKIX.

We rely and will continue to rely on certain third parties as the sole source of the materials they supply or the finished products they manufacture. For example, we rely on Interor S.A., Corden Pharma Chenôve SAS and Patheon UK Limited to provide intermediate supply ingredients, API and finished products, respectively.

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Additionally, we rely on our suppliers and manufacturers to purchase materials from other third parties. Any of our existing suppliers or manufacturers may:

In the event of any of the foregoing, if we do not have an alternative supplier or manufacturer in place, we would be required to expend substantial management time and expense to identify, qualify and transfer technical processes to alternative suppliers or manufacturers. Transferring technology to other sites may require additional processes, technologies and validation studies, which are costly, may take considerable amounts of time, may not be successful and, in most cases, require review and approval by the FDA. Any need to find and qualify new suppliers or manufacturers could significantly delay production of WAKIX, adversely impact our ability to market WAKIX and adversely affect our business.

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There can be no assurance that replacements would be available to us on a timely basis, on acceptable terms or at all. Additionally,While we and our manufacturers do not currently maintain significanta robust supply of raw material inventory and an 18 month supply of drug substances and other materials beyond our currently forecasted needs. Anyfinished good inventory to ensure product availability, any interruption in the supply of a drug substance or other material or in the manufacture of WAKIX could have a material adverse effect on our business, financial condition, operating results and prospects.

Additionally, although we are ultimately responsible for ensuring compliance with regulatory requirements such as cGMPs, we are dependent on our contract suppliers and manufacturers for day-to-day compliance with cGMP for production of both drug substances and finished products. Facilities used by our contract suppliers and manufacturers to produce the drug substances and materials or finished products for commercial sale must pass inspection and be approved by the FDA and other relevant regulatory authorities. A number of our contract suppliers and manufacturers must comply with cGMP requirements enforced by the FDA through its facilities inspection program and review of submitted technical information. If the safety of WAKIX is compromised due to a failure to adhere to applicable laws or for other reasons, we may not be able to successfully commercialize our product and we may be held liable for injuries sustained as a result. In addition, the manufacturing facilities of certain of our suppliers are located outside of the United States. This may give rise to difficulties in importing our product into the United States or other countries as a result of, among other things, regulatory agency approval requirements, taxes, tariffs, local import requirements such as import duties or inspections, incomplete or inaccurate import documentation or defective packaging.

Any of these factors could adversely impact our ability to effectively commercialize WAKIX.

Because a number of companies compete with us, many of which have greater resources than we do, and because we face rapid changes in science in our industry, we cannot be certain that our products will be accepted in the marketplace or capture market share.

Competition from other biotechnology and pharmaceutical companies is intense and is expected to increase. There may be a number of companies pursuing the development of pharmaceuticals in rare neurological disorders, our area of focus. These companies may be very large, and may have financial, technical, sales and distribution and other resources substantially greater than ours. The greater resources of these competitors may enable them to develop, obtain regulatory approval for or market competing products

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more quickly or effectively, making it extremely difficult for us to capture a share of the market for our product. We also face competition, and may in the future face additional competition, from manufacturers of generic drugs. Certain U.S. state laws allow for, and in some instances in the absence of specific instructions from the prescribing physician mandate, the dispensing of generic products rather than branded products when a generic version is available.

Generic competition often results in decreases in the prices at which branded products can be sold. The commercial potential of our current products and any future products may be reduced or eliminated if our competitors develop or acquire and commercialize generic or branded products that are safer or more effective, have fewer side effects, are easier to administer or are less expensive than our products. We also face competition from off-label uses of approved drugs. Additionally, the biotechnology and pharmaceutical industries are subject to rapid changes in science, and our competitors may develop and market products with improved therapeutic profiles relative to pitolisant or any future product candidates that would render pitolisant or any future product candidates noncompetitive.

We may need to increase the size and capabilities of our organization based on business need, and we may experience difficulties in managing our growth.

We commenced operations in 2017 and, as of December 31, 2020,2021, had approximately 150180 employees. As we advance the development of pitolisant in other indications and commercialize WAKIX as a treatment for EDS in adult patients with narcolepsy and cataplexy in adult patients with narcolepsy, we must continue to grow the size of the organization. Future growth will impose significant added responsibilities on members of management, including:

Our future financial performance and our ability to successfully develop and commercialize WAKIX or any future product candidates will depend, in part, on our ability to effectively manage any future growth. Our management will have to dedicate a significant amount of its attention to managing these growth activities. In addition, we expect to incur additional costs in hiring, training and retaining such additional personnel.

If we are not able to effectively expand our organization, we may not be able to successfully execute the tasks necessary to further develop and commercialize pitolisant or any future product candidates and, accordingly, may not achieve our research, development and commercialization goals.

Our future success depends on our ability to retain our key executives and to attract, retain and motivate qualified personnel.

We are highly dependent on the principal members of our management and scientific teams. We do not maintain “key person” insurance for any of our executives or other employees. The loss of the services of any of these persons could impede the achievement of our research, development and commercialization objectives.

To encourage valuable employees to remain at our company, in addition to salary and cash incentives, we have provided equity award grants that vest over time. The value to employees of these equity grants that vest over time may be significantly affected by changes in the price of our common stock that are beyond our control, and may at any time be insufficient to retain employees who receive more lucrative offers from other companies. Any of our employees could leave our employment at any time, with or without notice.

Recruiting and retaining qualified operations, finance and accounting, quality and compliance, scientific, clinical, manufacturing and sales and marketing personnel or consultants will also be critical to our success. We may not be able to attract and retain these personnel on acceptable terms, given the competition among numerous pharmaceutical and biotechnology companies for similar personnel. We also experience competition for the hiring of scientific and clinical personnel from universities and research institutions. If we are unable to attract, retain and motivate qualified and experienced personnel, it could harm our business, results of operations and financial condition. Even if we are successful in attracting and retaining such personnel,

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competition for such employees may significantly increase our compensation costs and adversely affect our business, results of operations and financial condition.

The loss of the services of any of our executive officers, key employees or consultants could seriously harm our ability to successfully implement our business strategy. Replacing executive officers, key employees or consultants may be difficult and may take an extended period of time because of the limited number of individuals in our industry with the breadth of skills and experience required to successfully develop, gain regulatory approval of and commercialize products. Competition to hire from this limited pool is intense, and we may be unable to hire, train, retain or motivate these key personnel or consultants on acceptable terms given the competition among numerous pharmaceutical and biotechnology companies for similar personnel.

We may hire part-time employees or use consultants. As a result, certain of our employees, officers, directors or consultants may not devote all of their time to our business, and may from time to time serve as employees, officers, directors and consultants of other companies.

We or the third parties upon whom we depend may be adversely affected by natural disasters and our business continuity and disaster recovery plans may not adequately protect us from a serious disaster.

Any unplanned event, such as flood, fire, explosion, earthquake, extreme weather condition, medical epidemics, power shortage, telecommunication failure or other natural or manmade accidents or incidents that result in us being unable to fully utilize our facilities, the manufacturing facilities of our third-party contract manufacturers or our or their distribution networks, may have a material and adverse effect on our ability to operate our business, particularly on a daily basis, and have significant negative consequences on our financial and operating conditions. Loss of access to these facilities may

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result in increased costs, or interruptions in the commercialization of WAKIX or our business operations. Natural disasters could further disrupt our operations, and have a material and adverse effect on our business, financial condition, results of operations and prospects. If a natural disaster, power outage or other event occurred that prevented us from using all or a significant portion of our headquarters, that damaged critical infrastructure, such as our research facilities, the manufacturing facilities of our third-party contract manufacturers or our or their distribution networks, or that otherwise disrupted operations, it may be difficult or, in certain cases, impossible, for us to continue our business for a substantial period of time.

The disaster recovery and business continuity plans we have in place may prove inadequate in the event of a serious disaster or similar event. We may incur substantial expenses as a result of the limited nature of our disaster recovery and business continuity plans, which could have a material adverse effect on our business. As part of our risk management policy, we maintain insurance coverage at levels that we believe are appropriate for our business. However, in the event of an accident or incident at these facilities, we cannot assure our investors that the amounts of insurance will be sufficient to satisfy any damages and losses. If our facilities or the manufacturing facilities of our third-party contract manufacturers are unable to operate because of an accident or incident or for any other reason, even for a short period of time, any or all of our research and development programs may be harmed. Any business interruption may have a material and adverse effect on our business, financial condition, results of operations and prospects.

We depend on our information technology systems, and any failure of these systems could harm our business. Any real or perceived security breaches, loss of data, and other disruptions or incidents could compromise the privacy, security, integrity or confidentiality of sensitive information related to our business or prevent us from accessing critical information and expose us to liability and reputational harm, which could adversely affect our business, results of operations and financial condition.

We collect and maintain data and information that is necessary to conduct our business, and we are increasingly dependent on information technology systems and infrastructure to operate our business, including systems infrastructure operated and maintained by our third party suppliers or providers. In the ordinary course of our business, we collect, store and transmit large amounts of confidential information, including intellectual property, proprietary business information and personal information. It is critical that we do so in a secure manner to maintain the privacy, security, confidentiality and integrity of such confidential information. We have established physical, electronic and organizational measures to safeguard and secure our systems and facilities to prevent an information compromise, and rely on commercially available systems, software, tools and monitoring to provide security for our information technology systems and the processing, transmission and storage of digital information. We have also outsourced elements of our information technology infrastructure, and as a result, a number of third-party vendors may or could have access to our confidential information. Our internal information technology systems and infrastructure, and those of our current and any future

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collaborators, contractors and consultants and other third parties on which we rely, are vulnerable to damage or unauthorized access or use resulting from computer viruses, malware, natural disasters, terrorism, war, telecommunication and electrical failures, denial-of-service attacks, cyber- attacks or cyber-intrusions over the Internet, hacking, phishing and other social engineering attacks, attachments to emails, persons inside our organization (including employees or contractors), lost or stolen devices, or persons with access to systems inside our organization.

The risk of a security breach or disruption or data loss, particularly through social engineering attacks, cyber-attacks or cyber intrusion, including by computer hackers, foreign governments and cyber terrorists, has generally increased as the number, intensity and sophistication of attempted attacks and intrusions from around the world have increased. In addition, the prevalent use of mobile devices that access confidential information increases the risk of data security breaches, which could lead to the loss of confidential information or other intellectual property. As a result of the COVID-19 pandemic, we may also face increased cybersecurity risks due to our reliance on internet technology and the number of our employees who are working remotely, which may create additional opportunities for cybercriminals to exploit vulnerabilities. Furthermore, because the techniques used to obtain unauthorized access to, or to sabotage, systems change frequently and often are not recognized until launched against a target, we may be unable to anticipate these techniques or implement adequate preventative measures. We may also experience security breaches that may remain undetected for an extended period. The costs to us to mitigate, investigate and respond to potential security incidents, breaches, disruptions, network security problems, bugs, viruses, worms, malicious software programs and security vulnerabilities could be significant, and while we have implemented security measures to protect our data security and information technology systems, our efforts to address these problems may not be successful, and these problems could result in unexpected interruptions, delays, cessation of service and other harm to our business and our competitive position. If such an event were to occur and cause interruptions in our operations, it could result in a material disruption of our product development programs. For example, the loss of clinical trial data from completed or ongoing or planned clinical trials could result in delays in our regulatory

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approval efforts and significantly increase our costs to recover or reproduce the data. Moreover, if a real or perceived security breach affects our systems (or those of our third party providers or suppliers) or results in the loss of or accidental, unlawful or unauthorized access to, use of, release of or other processing of personally identifiable information or clinical trial data, our reputation could be materially damaged. In addition, such a breach may require notification to governmental agencies, the media or individuals pursuant to various federal and stateapplicable data privacy and security laws, if applicable, including HIPAA, as amended by the Health Information Technology for Economic and Clinical Health Act of 2009 (“HITECH”), and its implementing rules and regulations, as well as regulations promulgated by the Federal Trade Commission and state breach notification laws. We would also be exposed to a risk of loss, negative publicity, harm to our reputation, governmental investigation and/or enforcement actions, claims or litigation and potential liability, which could materially adversely affect our business, results of operations and financial condition. The global data protection landscape is rapidly evolving, and we may be affected by or subject to new, amended or existing laws and regulations in the future, including as our operations continue to expand or if we begin to operate in foreign jurisdictions.

Our employees and independent contractors, including principal investigators, consultants, commercial collaborators, service providers and other vendors may engage in misconduct or other improper activities, including noncompliance with regulatory standards and requirements, which could have an adverse effect on our results of operations.

We are exposed to the risk that our employees and independent contractors, including principal investigators, consultants, any future commercial collaborators, service providers and other vendors may engage in misconduct or other illegal activity. Misconduct by these parties could include intentional, reckless and/or negligent conduct or other unauthorized activities that violate the laws and regulations of the FDA and other similar regulatory bodies, including those laws that require the reporting of true, complete and accurate information to such regulatory bodies; manufacturing standards; U.S. federal and state healthcare fraud and abuse laws, data privacy and security laws and other similar non-U.S. laws; or laws that require the true, complete and accurate reporting of financial information or data. In particular, sales, marketing and business arrangements in the healthcare industry are subject to extensive laws and regulations intended to prevent fraud, misconduct, kickbacks, self-dealing and other abusive practices. These laws and regulations restrict or prohibit a wide range of pricing, discounting, marketing and promotion, sales commission, customer incentive programs, and other business arrangements. Such misconduct also could involve the improper use or misrepresentation of individually identifiable information, including, without limitation, information obtained in the course of clinical trials, the creation of fraudulent data in our preclinical studies or clinical trials, or illegal misappropriation of product, which could result in regulatory sanctions and cause serious harm to our reputation. It is not always possible to identify and deter misconduct by employees and other third-parties, and the precautions we take to

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detect and prevent this activity may not be effective in controlling unknown or unmanaged risks or losses or in protecting us from governmental investigations or other actions or lawsuits stemming from a failure to be in compliance with such laws or regulations. In addition, we are subject to the risk that a person or government could allege such fraud or other misconduct, even if none occurred. If any such actions are instituted against us, and we are not successful in defending ourselves or asserting our rights, those actions could have a significant impact on our business and financial results, including, without limitation, the imposition of significant civil, criminal and administrative penalties, damages, monetary fines, disgorgement, possible exclusion from participation in Medicare, Medicaid and other U.S. federal healthcareprograms or healthcare programs in other jurisdictions, integrity oversight and reporting obligations to resolve allegations of non-compliance, imprisonment, other sanctions, contractual damages, reputationalharm, diminished profits and future earnings and curtailment of our operations, any of which could adversely affect our ability to operate our business and our results ofoperations.

Risks Related to Development, Regulatory Approval and Commercialization

The regulatory approval process of the FDA is costly, lengthy and inherently unpredictable, and if we are ultimately unable to obtain regulatory approval for pitolisant in other potential indications for which we may seek to develop pitolisant, our business will be substantially harmed.

Although the commercialization of WAKIX is our primary focus, as part of our longer-term growth strategy, we plan to evaluate pitolisant in other indications and develop other product candidates. The research, testing, manufacturing, labeling, approval, selling, import, export, pricing and reimbursement marketing and distribution of drug products are subject to extensive regulation by the FDA and other regulatory agencies in the United States. Although we have obtained regulatory approval for WAKIX in the United States for the treatment of EDS or cataplexy in adult patients with narcolepsy, it is possible that we may not obtain regulatory approval for pitolisant for other indications, or for any other product candidates we may seek to develop in the future. We received a Complete Response Letter for pitolisant for the treatment of cataplexy in adult patients with narcolepsy, and therefore the FDA did not approve WAKIX for this indication during the initial NDA review. Subsequently, in June 2020, we received a general advice letter from the FDA stating that the FDA had re-analyzed data

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from the HARMONY 1 trial that we submitted in the NDA in support of the adult cataplexy indication for WAKIX. As a result, the FDA recommended we submit a complete response resubmission in pursuit of the adult cataplexy indication for WAKIX. Following such resubmission, we received acknowledgement from the FDA that it considers the resubmission to be a complete Class 1 response to its August 14, 2019 action letter, and the user fee goal date, or decision date, was October 13, 2020. On October 13, 2020 we received regulatory approval for WAKIX for the treatment of cataplexy in adult patients with narcolepsy. Nevertheless, obtaining regulatory approval of an NDA can be a lengthy, expensive and uncertain process.

The FDA can delay, limit or deny approval of a drug candidate for many reasons or require us to conduct additional preclinical or clinical testing, including, but not limited to, the following:

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Prior to obtaining approval to commercialize a drug candidate in the United States, we or our collaborators must demonstrate with substantial evidence from well-controlled clinical trials, and to the satisfaction of the FDA, that such drug candidates are safe and effective for their intended uses. The number of nonclinical and clinical studies and trials that will be required for FDA approval varies depending on the drug candidate, the disease or condition that the drug candidate is designed to address, and the regulations applicable to any particular drug candidate. In addition, data obtained from preclinical trials and clinical trials are susceptible to varying interpretations, and regulatory authorities may not interpret our data as favorably as we do, which may further delay, limit or prevent development efforts, clinical trials or marketing approval. Furthermore, as more competing drug candidates within a particular class of drugs proceed through clinical development to regulatory review and approval, the amount and type of clinical data that may be required by regulatory authorities may increase or change. Even if we believe the preclinical or clinical data for our product candidates are promising, such data may not be sufficient to support approval by the FDA and other regulatory authorities. If pitolisant fails to demonstrate safety and efficacy in clinical trials or does not gain regulatory approval for other indications, our business and results of operations will be materially and adversely harmed. Additionally, if the FDA requires that we conduct additional clinical trials, places limitations on pitolisant in our label, delays approval to market pitolisant or limits the use of pitolisant, our business and results of operations may be harmed.

Moreover, principal investigators for our clinical trials may serve as scientific advisors or consultants to us from time to time and receive compensation in connection with such services. Under certain circumstances, we may be required to report some of these relationships to the FDA or comparable foreign regulatory authorities. The FDA or comparable foreign regulatory authority may conclude that a financial relationship between us and a principal investigator has created a conflict of interest or otherwise affected interpretation of the study. The FDA or comparable foreign regulatory authority may therefore question the integrity of the data generated at the applicable clinical trial site and the utility of the clinical trial itself may be jeopardized. This could result in a delay in approval, or rejection, of our marketing applications by the FDA or comparable foreign regulatory authority, as the case may be, and may ultimately lead to the denial of marketing approval of one or more of our product candidates.

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If we fail to obtain and sustain an adequate level of coverage and reimbursement for WAKIX and other product candidates by third-party payors, sales would be adversely affected.

Successful sales of WAKIX and any other product candidates that may receive regulatory approval depend on the availability of coverage and adequate reimbursement from third-party payors. Patients who are prescribed medications for the treatment of their conditions generally rely on third- party payors to reimburse all or part of the costs associated with their prescription drugs. There is significant uncertainty related to third-party payor coverage and reimbursement of newly approved drugs. Regulatory approvals, pricing and reimbursement for new drug products vary widely from country to country. In the United States, the principal decisions about reimbursement for new medicines are typically made by CMS, an agency within HHS. CMS decides whether and to what extent a new medicine will be covered and reimbursed under Medicare. Private payors tend to follow CMS to a substantial degree. Commercial third-party payors, such as private health insurers and health maintenance organizations, also decide which medications they will pay for and establish reimbursement levels, though commercial third-party payors often follow CMS’ reimbursement determinations. The availability of coverage and the extent of reimbursement by governmental and private payors is essential for most patients to be able to afford treatments. Sales of WAKIX or other product candidates that we may identify will depend substantially, both domestically and abroad, on the extent to which the costs of our product candidates will be paid by health maintenance, managed care, pharmacy benefit and similar healthcare management organizations, or reimbursed by government health administration authorities, private health coverage insurers and other third-party payors.

Coverage and reimbursement by a third-party payor may depend upon a number of factors, including the third-party payor’s determination that use of a product is:

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Ensuring that our business operations and current and future arrangements with third parties comply with applicable healthcare laws and regulations will likely be costly. It is possible that governmental authorities will conclude that our business practices, including, without limitation, our patient support and financial assistance programs, do not comply with current or future statutes, regulations, agency guidance or case law involving applicable fraud and abuse or other healthcare laws. If our operations are found to be in violation of any of the laws described above or any other governmental laws and regulations that apply to us, we may be subject to penalties, including civil, administrative and criminal penalties, damages, fines, the curtailment or restructuring of our operations, contractual damages, disgorgement, reputational harm, additional oversight and reporting obligations if we become subject to a corporate integrity agreement or similar agreement to resolve allegations of non-compliance with these laws, the exclusion from participation in federal and state healthcare programs and individual imprisonment, any of which could adversely affect our ability to market pitolisant, if approved, and adversely impact our financial results. Further, defending against any such actions can be costly, time-consuming and may require significant personnel resources.

Therefore, even if we are successful in defending against any such actions that may be brought against us, our business may be impaired. The risk of our being found in violation of these laws is increased by the fact that many of them have not been fully interpreted by the applicable regulatory agencies or the courts, and their provisions are open to a variety of interpretations.

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Actual or perceived failures to comply with applicable data protection, privacy and security laws, regulations, standards and other requirements could adversely affect our business, results of operations, and financial condition.

The global data protection landscape is rapidly evolving, and we are or may become subject to numerous state, federal and foreign laws, requirements and regulations governing the collection, use, disclosure, retention, and security of personal data, such as information that we may collect in connection with clinical trials in the U.S. and abroad. Implementation standards and enforcement practices are likely to remain uncertain for the foreseeable future, and we cannot yet determine the impact future laws, regulations, standards, or perception of their requirements may have on our business. This evolution may create uncertainty in our business, affect our ability to operate in certain jurisdictions or to collect, store, transfer use and share personal information, necessitate the acceptance of more onerous obligations in our contracts, result in liability or impose additional costs on us. The cost of compliance with these laws, regulations and standards is high and is likely to increase in the future. Any failure or perceived failure by us to comply with federal, state or foreign laws or regulation, our internal policies and procedures or our contracts governing our processing of personal information could result in negative publicity, government investigations and enforcement actions, claims by third parties and damage to our reputation, any of which could have a material adverse effect on our operations, financial performance and business.

Certain states have also adopted comparable privacy and security laws and regulations, some of which may be more stringent than HIPAA. Such laws and regulations will be subject to interpretation by various courts and other governmental authorities, thus creating potentially complex compliance issues for us and our future customers and strategic partners. In addition, the California Consumer Privacy Act of 2018 (the “CCPA”) went into effect on January 1, 2020. The CCPA creates individual privacy rights for California consumers and increases the privacy and security obligations of entities handling certain personal information. The CCPA provides for civil penalties for violations, as well as a private right of action for data breaches that is expected to increase data breach litigation. The CCPA may increase our compliance costs and potential liability, and many similar laws have been proposed at the federal level and in other states. Further, the California Privacy Rights Act (the “CPRA”) recently passed in California. The CPRA will impose additional data protection obligations on covered businesses, including additional consumer rights processes, limitations on data uses, new audit requirements for higher risk data, and opt outs for certain uses of sensitive data. It will also create a new California data protection agency authorized to issue substantive regulations and could result in increased privacy and information security enforcement. The

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majority of the provisions will go into effect on January 1, 2023, and additional compliance investment and potential business process changes may be required. In the event that we are subject to or affected by HIPAA, the CCPA, the CPRA or other domestic privacy and data protection laws, any liability from failure to comply with the requirements of these laws could adversely affect our financial condition.

As our operations and business grow, we may become subject to or affected by new or additional data protection laws and regulations and face increased scrutiny or attention from regulatory authorities. In the U.S., HIPAA imposes, among other things, certain standards relating to the privacy, security, transmission and breach reporting of individually identifiable health information. Most healthcare providers, including research institutions from which we obtain patient health information, are subject to privacy and security regulations promulgated under HIPAA, as amended by HITECH. While we do not believe that we are currently acting as a covered entity or business associate under HIPAA and thus are not directly subject to its requirements or penalties. However, any person may be prosecuted under HIPAA’s criminal provisions either directly or under aiding-and-abetting or conspiracy principles. Consequently, depending on the facts and circumstances, we could face substantial criminal penalties if we knowingly receive individually identifiable health information from a HIPAA-covered healthcare provider or research institution that has not satisfied HIPAA’s requirements for disclosure of individually identifiable health information. In addition, we may maintain sensitive personally identifiable information, including health information, that we receive throughout the clinical trial process, in the course of our research collaborations, and directly from individuals (or their healthcare providers) who enroll in our patient assistance programs. As such, we may be subject to state laws requiring notification of affected individuals and state regulators in the event of a breach of personal information, which is a broader class of information than the health information protected by HIPAA.

Furthermore, certain health privacy laws, data breach notification laws, consumer protection laws and genetic testing laws may apply directly to our operations and/or those of our collaborators and may impose restrictions on our collection, use and dissemination of individuals’ health information. Patients about whom we or our collaborators obtain health information, as well as the providers who share this information with us, may have statutory or contractual rights that limit our ability to use and disclose the information. We may be required

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to expend significant capital and other resources to ensure ongoing compliance with applicable privacy and data security laws. Claims that we have violated individuals’ privacy rights or breached our contractual obligations, even if we are not found liable, could be expensive and time consuming to defend and could result in adverse publicity that could harm our business.

In Europe, the GDPR went into effect in May 2018 and imposes strict requirements for processing the personal data of individuals within the EEA. Companies that must comply with the GDPR face increased compliance obligations and risk, including more robust regulatory enforcement of data protection requirements and potential fines for noncompliance of up to €20 million or 4% of the annual global revenues of the noncompliant company, whichever is greater. Among other requirements, the GDPR regulates transfers of personal data subject to the GDPR to third countries that have not been found to provide adequate protection to such personal data, including the United States, and the efficacy and longevity of current transfer mechanisms between the EU and the United States remains uncertain. For example, in 2016, the EU and United States agreed to a transfer framework for data transferred from the EU to the United States, called the Privacy Shield, but the Privacy Shield was invalidated inShield. In July 2020, by the Court of Justice of the European Union. Union (“CJEU”) invalidated the Privacy Shield for purposes of international transfers and imposed further restrictions on the use of standard contractual clauses (“SCCs”). The European Commission issued revised SCCs on June 4, 2021 to account for the decision of the CJEU and recommendations made by the European Data Protection Board. The revised SCCs must be used for relevant new data transfers from September 27, 2021; existing standard contractual clauses arrangements must be migrated to the revised clauses by December 27, 2022. The new SCCs apply only to the transfer of personal data outside of the EEA and not the UK; the UK’s Information Commissioner’s Office launched a public consultation on its draft revised data transfers mechanisms in August 2021. There is some uncertainty around whether the revised clauses can be used for all types of data transfers, particularly whether they can be relied on for data transfers to non-EEA entities subject to the GDPR. As supervisory authorities issue further guidance on personal data export mechanisms, including circumstances where the SCCs cannot be used, and/or start taking enforcement action, we could suffer additional costs, complaints and/or regulatory investigations or fines, and/or if we are otherwise unable to transfer personal data between and among countries and regions in which we operate, it could affect the manner in which we provide our services, the geographical location or segregation of our relevant systems and operations, and could adversely affect our financial results.

Further, from January 1, 2021, companies have to comply with the GDPR and also the UK GDPR, which, together with the amended UK Data Protection Act 2018, retains the GDPR in UK national law. The UK GDPR mirrors the fines under the GDPR, i.e., fines up to the greater of €20 million (£17.5 million) or 4% of global turnover. The relationship between the United Kingdom and the European Union in relation to certain aspects of data protection law remains unclear, and it is

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unclear how United Kingdom data protection laws and regulations will develop in the medium to longer term, and how data transfers to and from the United Kingdom will be regulated in the long term. Currently there is a four to six-month grace period agreed in the EU and United Kingdom Trade and Cooperation Agreement, ending June 30, 2021 at the latest, whilst the parties discuss an adequacy decision. However, it is not clear whether (and when)The European Commission has adopted an adequacy decision may be granted byin favor of the European CommissionUnited Kingdom, enabling data transfers from EU member states to the United Kingdom long term without additional measures. These changes may lead to additional costssafeguards. However, the UK adequacy decision will automatically expire in June 2025 unless the European Commission re-assesses and increase our overall risk exposure.renews or extends that decision.

Although we work to comply with applicable laws, regulations and standards, our contractual obligations and other legal obligations, these requirements are evolving and may be modified, interpreted and applied in an inconsistent manner from one jurisdiction to another, and may conflict with one another or other legal obligations with which we must comply. If we or third-party CMOs, CROs or other contractors or consultants fail to comply with applicable federal, state or local regulatory requirements, we could be subject to a range of regulatory actions that could affect our or our contractors’ ability to develop and commercialize our product candidates and could harm or prevent sales of any affected products that we are able to commercialize, or could substantially increase the costs and expenses of developing, commercializing and marketing our products. Any threatened or actual government enforcement action could also generate adverse publicity and require that we devote substantial resources that could otherwise be used in other aspects of our business. Increasing use of social media could give rise to liability, breaches of data security or reputational damage.

Clinical practice guidelines and recommendations published by various organizations could have significant influence on the use of WAKIX.

Professional societies, practice management groups, private health and science foundations and organizations involved in various diseases from time to time may publish guidelines or recommendations to the healthcare and patient communities. The recommendations of these groups or organizations may relate to such matters as usage, dosage, route of administration and use of concomitant therapies. Recommendations or guidelines suggesting the reduced use of WAKIX or the use of competitive or alternative products as the standard of care to be followed by patients and healthcare providers could result in decreased use of WAKIX.

Product candidates we develop in the future may be classified as controlled substances, the making, use, sale, importation, exportation and distribution of which are subject to regulation by state, federal and foreign law enforcement and other regulatory agencies.

Product candidates we develop in the future may be classified as controlled substances, which are subject to state, federal and foreign laws and regulations regarding their manufacture, use, sale, importation, exportation and distribution. Controlled substances are regulated under CSA and regulations of the DEA.

The DEA regulates controlled substances as Schedule I, II, III, IV or V substances. Schedule I substances by definition have no established medicinal use and may not be marketed or sold in the United States. A pharmaceutical product may be listed as Schedule II, III, IV or V, with Schedule II substances

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considered to present the highest risk of abuse and Schedule V substances the lowest relative risk of abuse among such substances.

Various states also independently regulate controlled substances. Though state controlled substances laws often mirror federal law, because the states are separate jurisdictions, they may separately schedule drugs as well. While some states automatically schedule a drug when the DEA does so, in other states there must be rulemaking or a legislative action. State scheduling may delay commercial sale of any controlled substance drug product for which we obtain federal regulatory approval and adverse scheduling could impair the commercial attractiveness of such product. We or our collaborators must also obtain separate state registrations in order to be able to obtain, handle and distribute controlled substances for clinical trials or commercial sale, and failure to meet applicable regulatory requirements could lead to enforcement and sanctions from the states in addition to those from the DEA or otherwise arising under federal law.

For any of our products or product candidates classified as controlled substances, we and our suppliers, manufacturers, contractors, customers and distributors are required to obtain and maintain applicable registrations from state, federal and foreign law enforcement and regulatory agencies and comply with state, federal and foreign laws and regulations regarding the manufacture, use, sale, importation, exportation and distribution of controlled substances. There is a risk that DEA regulations may limit the supply of the compounds used in clinical trials for our product candidates, and, in the case of our approved products, the ability to produce and distribute our products in the volume needed to meet commercial demand.

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Regulations associated with controlled substances govern manufacturing, labeling, packaging, testing, dispensing, production and procurement quotas, recordkeeping, reporting, handling, shipment and disposal. These regulations increase the personnel needs and the expense associated with development and commercialization of product candidates including controlled substances. The DEA, and some states, conduct periodic inspections of registered establishments that handle controlled substances. Failure to obtain and maintain required registrations or comply with any applicable regulations could delay or preclude us from developing and commercializing our product candidates containing controlled substances and subject us to enforcement action. The DEA may seek civil penalties, refuse to renew necessary registrations or initiate proceedings to revoke those registrations. In some circumstances, violations could lead to criminal proceedings. Because of their restrictive nature, these regulations could limit commercialization of any of our approved products or product candidates that are classified as controlled substances.

Enacted and future healthcare legislative changes may increase the difficulty and cost for us to obtain marketing approval for and commercialize our product candidates and affect the prices we may obtain.

In the United States, the European Union and other some foreign jurisdictions, there have been, and we expect there will continue to be, a number of legislative and regulatory changes and proposed changes regarding the healthcare system that could, among other things, prevent or delay marketing approval of our product candidates, restrict or regulate post-approval activities, and affect our ability to profitably sell any products for which we obtain marketing approval. In particular, there have been and continue to be a number of initiatives at the U.S. federal and state levels that seek to reduce healthcare costs and improve the quality of healthcare. For example, in March 2010, the Patient Protection and Affordable Care Act, as amended by the Health Care and Education Reconciliation Act, collectively the ACA, was enacted to broaden access to health insurance, reduce or constrain the growth of healthcare spending, enhance remedies against fraud and abuse, add new transparency requirements for health care and health insurance industries, impose new taxes and fees on the healthcare industry, and impose additional healthcare policy reforms. The law has continued the downward pressure on pharmaceutical pricing, especially under the Medicare program, and increased the industry’s regulatory burdens and operating costs. Among the provisions of the ACA of importance to the pharmaceutical industry and our potential product candidates are the following:

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Since its enactment, there have been numerous judicial, executive and legislative challenges to certain aspects of the ACA. TheOn June 17, 2021 the U.S. Supreme Court is currently reviewingdismissed the most recent judicial challenge to the ACA brought by several states without specifically ruling on the constitutionality of the ACA in its entirety. It is unclear whetherACA. Thus, the ACA will be overturned, repealed, replaced, or further amended. We cannot predict what affect further changesremain in effect in its current form. Further, prior to the U.S. Supreme Court ruling, President Biden issued an executive order to initiate a special enrollment period from February 15, 2021 through August 15, 2021 for purposes of obtaining health insurance coverage through the ACA would have on our business.marketplace. The executive order also instructed certain governmental agencies to review and reconsider their existing policies and rules that limit access to healthcare, including among others, reexamining Medicaid demonstration projects and waiver programs that include work requirements, and policies that create unnecessary barriers to obtaining access to health insurance coverage through Medicaid or the ACA.

Other legislative changes have been proposed and adopted in the United States since the ACA was enacted. For example, in August 2011, the Budget Control Act of 2011, among other things, led to aggregate reductions to Medicare payments to providers of 2% per fiscal year, which went into effect in April 2013 and, due to subsequent legislative amendments to the statute, will stay in effect through 2030, with the exception of a temporary suspension from May 1, 2020 through MarchDecember 31, 2021,2022, unless additional Congressional action is taken. Additionally, in January 2013, the American Taxpayer Relief Act of 2012 was signed into law, which, among other things, reduced Medicare payments to several types of providers, including hospitals and cancer treatment centers, and increased the statute of limitations period in which the government may recover overpayments to providers from three to five years.

Moreover, payment methodologies may be subject to changes in healthcare legislation and regulatory initiatives. For example, CMS may develop new payment and delivery models, such as bundled payment models. In addition, recently there has been heightened governmental scrutiny over the manner in which manufacturers set prices for their marketed products, which has resulted in several U.S. Congressional inquiries and proposed and enacted federal and state legislation designed to, among other things, bring more transparency to drug pricing, reduce the cost of prescription drugs under government payor programs, and review the relationship between pricing and manufacturer patient programs. While any proposed measures will require authorization through additional legislation to become effective, the probability of their success is uncertain, particularly in light of the new Presidential administration.

Individual states in the United States have also increasingly passed legislation and implemented regulations designed to control pharmaceutical and biological product pricing, including price or patient reimbursement constraints, discounts, restrictions on certain product access and marketing cost disclosure and transparency measures, and, in some cases, designed to encourage importation from other countries and bulk purchasing. Legally mandated price controls on payment amounts by third- party payors or other restrictions could harm our business, results of operations, financial condition and prospects. In addition, regional healthcare authorities and individual hospitals are increasingly using bidding procedures to determine what pharmaceutical products and which suppliers will be included in their prescription drug and other healthcare programs. Furthermore, there has been increased interest by third party payors and governmental authorities in reference pricing systems and publication of discounts and list prices. These reforms could reduce the ultimate demand for our commercial products and product candidates, once approved, or put pressure on our product pricing.

In the European Union, similar political, economic and regulatory developments may affect our ability to profitably commercialize our product candidates, if approved. In addition to continuing pressure on prices and

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cost containment measures, legislative developments at the European Unionor member state level may result in significant additional requirements or obstacles that may increase our operating costs. The delivery of healthcare in the European Union, including the establishment and operation of health services and the pricing and reimbursement of medicines, is almost exclusively a matter for national, rather than European Union, law and policy. National governments and health service providers have different priorities and approaches to the delivery of health care and the pricing and reimbursement of products in that context. In general, however, the healthcare budgetary constraints in most European Union member states have resulted in restrictions on the pricing and reimbursement of medicines by relevant health service providers. Coupled with ever-increasing European Union and national regulatory burdens on those wishing to develop and market products, this could prevent or delay marketing approval of our product candidates, restrict or regulate post- approvalpost-approval activities and affect our ability to commercialize our product candidates, if approved. In markets outside of the United States and European Union, reimbursement and healthcarepayment systems vary significantly by country, and many countries have instituted price ceilings on specific products and therapies.

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We cannot predict the likelihood, nature or extent of government regulation that may arise from future legislation or administrative action in the United States, the European Union or any other jurisdiction. If we or any third parties we may engage are slow or unable to adapt to changes in existing requirements or the adoption of new requirements or policies, or if we or such third parties are not able to maintain regulatory compliance, our current or any future product candidates we may develop may lose any regulatory approval that may have been obtained and we may not achieve or sustain profitability.

If we fail to comply with our reporting and payment obligations under the Medicaid Drug Rebate Program or other governmental pricing programs that we participate in, we could be subject to additional reimbursement requirements, penalties, sanctions and fines, which could have a material adverse effect on our business, financial condition, results of operations and growth prospects.

We participate in and have certain price reporting obligations to the Medicaid Drug Rebate Program. Under the Medicaid Drug Rebate Program, we are required to pay a rebate to each state Medicaid program for our covered outpatient drugs that are dispensed to Medicaid beneficiaries and paid for by a state Medicaid program as a condition of having federal funds being made available to the states for our drugs under Medicaid and Medicare Part B. Those rebates are based on pricing data we have to report on a monthly and quarterly basis to the CMS, the federal agency that administers the Medicaid Drug Rebate Program. These data include, among other things, the average manufacturer price (“AMP”) and, in the case of innovator products, the best price (“BP”) for each drug which, in general, represents the lowest price available from the manufacturer to any entity in the U.S. in any pricing structure, calculated to include all sales and associated rebates, discounts and other price concessions. We are liable for errors associated with our submission of pricing data and for any overcharging of government payors. For example, failure to submit monthly and/or quarterly AMP and BP data on a timely basis could result in a civil monetary penalty for each day the submission is late beyond the due date. Failure to make necessary disclosures and/or to identify overpayments could result in allegations against us under the Federal False Claims Act and other laws and regulations. Any required refunds to the U.S. government or responding to a government investigation or enforcement action would be expensive and time consuming and could have a material adverse effect on our business, results of operations and financial condition.

Federal law requires that any company that participates in the Medicaid Drug Rebate Program also participate in the 340B program in order for federal funds to be available for the manufacturer’s drugs under Medicaid and Medicare Part B. The 340B program requires participating manufacturers to agree to charge statutorily defined covered entities no more than the 340B “ceiling price” for the manufacturer’s covered outpatient drugs. These 340B covered entities include a variety of community health clinics and other entities that receive health services grants from the Public Health Service, as well as hospitals that serve a disproportionate share of low-income patients. The ACA expanded the list of covered entities to include certain free-standing cancer hospitals, critical access hospitals, rural referral centers and sole community hospitals, but exempts “orphan drugs” from the ceiling price requirements for these covered entities. The 340B ceiling price is calculated using a statutory formula based on the average manufacturer price and rebate amount for the covered outpatient drug as calculated under the Medicaid Drug Rebate Program, and in general, products subject to Medicaid price reporting and rebate liability are also subject to the 340B ceiling price calculation and discount requirement. Any additional future changes to the definition of average manufacturer price and the Medicaid rebate amount under the ACA or other legislation or regulation could affect our 340B ceiling price calculations and negatively impact our results of operations commercializing pitolisant. In addition, legislation may be introduced that, if passed, would further expand the 340B program to additional covered entities or would

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require participating manufacturers to agree to provide 340B discounted pricing on drugs used in an inpatient setting.

In order to be eligible to have our products that we successfully commercialize paid for with federal funds under the Medicaid program and purchased by certain federal agencies and grantees, we also have to participate in the U.S. Department of Veterans Affairs (“VA”), Federal Supply Schedule (“FSS”) pricing program. As part of this program, we are obligated to make our products available for procurement on an FSS contract under which we must comply with standard government terms and conditions and charge a price that is no higher than the statutory Federal Ceiling Price (“FCP”) to four federal agencies (VA, U.S. Department of Defense (“DOD”), Public Health Service, and U.S. Coast Guard).

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We are subject to U.S. and certain foreign export and import controls, sanctions, embargoes, anti-corruption laws, and antimony laundering laws and regulations. Compliance with these legal standards could impair our ability to compete in domestic markets. We can face criminal liability and other serious consequences for violations, which can harm our business.

We are subject to export control and import laws and regulations, including the U.S. Export Administration Regulations, U.S. Customs regulations, various economic and trade sanctions regulations administered by the U.S. Treasury Department’s Office of Foreign Assets Controls, the U.S. Foreign Corrupt Practices Act of 1977, as amended, the United States domestic bribery statute contained in 18 U.S.C. § 201, the United States Travel Act, the USA PATRIOT Act, and other state and national anti-bribery and anti-money laundering laws in the countries in which we conduct activities. Anti-corruption laws are interpreted broadly and prohibit companies and their employees, agents, contractors and other partners from authorizing, promising, offering, or providing, directly or indirectly, improper payments or anything else of value to recipients in the public or private sector. We may have direct or indirect interactions with officials and employees of government agencies or government- affiliated hospitals, universities, and other organizations. We can be held liable for the corrupt or other illegal activities of our employees, agents, contractors and other partners, even if we do not explicitly authorize or have actual knowledge of such activities. Any violations of the laws and regulations described above may result in substantial civil and criminal fines and penalties, imprisonment, the loss of export or import privileges, debarment, tax reassessments, breach of contract and fraud litigation, reputational harm and other consequences.

Disruptions at the FDA and other government agencies caused by funding shortages or global health concerns could hinder their ability to hire and retain key leadership and other personnel, or otherwise prevent new or modified products from being developed, approved or commercialized in a timely manner or at all, or otherwise prevent those agencies from performing normal business functions on which the operation of our business may rely, which could negatively impact our business.

The ability of the FDA to review and approve new products can be affected by a variety of factors, including government budget and funding levels, ability to hire and retain key personnel and accept the payment of user fees, and statutory, regulatory, and policy changes, and other events that may otherwise affect the FDA’s ability to perform routine functions. Average review times at the agency have fluctuated in recent years as a result. In addition, government funding of other government agencies on which our operations may rely, including those that fund research and development activities is subject to the political process, which is inherently fluid and unpredictable.

Disruptions at the FDA and other agencies may also slow the time necessary for new drugs to be reviewed and/or approved by necessary government agencies, which would adversely affect our business. For example, in recent years, including in 2018 and 2019, the U.S. government shut down several times and certain regulatory agencies, such as the FDA and the SEC, had to furlough critical employees and stop critical activities. Separately, in response to the COVID-19 pandemic, on March 10, 2020 the FDA announced its intention to postpone most inspections of foreign manufacturing facilities, and on March 18, 2020, the FDA announced its intention to temporarily postpone routine surveillance inspections of domestic manufacturing facilities and provided guidance regarding the conduct of clinical trials. Subsequently, on July 10, 2020, the FDA announced its intention to resume certain on-site inspections of domestic manufacturing facilities subject to a risk-based prioritization system. The FDA intends to use this risk-based assessment system to identify the categories of regulatory activity that can occur within a given geographic area, ranging from mission critical inspections to resumption of all regulatory activities. Regulatory authorities outside the United States may adopt similar restrictions or other policy measures in response to the COVID-19 pandemic. If a prolonged government shutdown occurs, or if global health concerns continue to prevent the FDA or other regulatory authorities from conducting their regular inspections, reviews, or other regulatory activities, it could significantly impact the

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ability of the FDA to timely review and process our regulatory submissions, which could have a material adverse effect on our business. Further, upon closing of this offering and in our operations as a U.S. public company, future government shutdowns or delays could impact our ability to access the public markets and obtain necessary capital in order to properly capitalize and continue our operations.

We will need to obtain FDA approval of any proposed product names, and any failure or delay associated with such approval may adversely affect our business.

Any proprietary name we intend to use for our product candidates will require approval from the FDA regardless of whether we have secured a formal trademark registration from the USPTO. The FDA reviews proposed product names, considering both the potential for the name to lead to medical errors due to confusion with other product names and whether the proposed name is overly fanciful, misleadingly implies unique effectiveness or composition, or contributes to

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overstatement of product efficacy, minimization of risk, broadening of product indications or unsubstantiated superiority. If the FDA objects to any of our proposed product names, we may be required to adopt an alternative name for our product candidates. If we adopt an alternative name, we would lose the benefit of our existing trademark applications for such product candidate, and may be required to expend significant additional resources in an effort to identify a suitable product name that would qualify under applicable trademark laws, not infringe the existing rights of third parties and be acceptable to the FDA. We may be unable to build a successful brand identity for a new trademark in a timely manner or at all, which would limit our ability to commercialize our product candidates.

Risks Related to Our Intellectual Property

If we are unable to obtain and maintain patent protection for our technology and products, or if the scope of the patent protection obtained is not sufficiently broad, we may not be able to compete effectively in our markets.

We rely, and will continue to rely, on a combination of patents, trademarks and confidentiality agreements with employees, consultants, collaborators, advisors and other third parties to protect the intellectual property related to our current and future product candidates. Our success depends in large part on our licensor’s ability to obtain and maintain patent protection in the United States with respect to WAKIX and our ability to obtain and maintain patent protection in the United States and any other relevant foreign jurisdictions with respect to any future product candidates that we develop. We seek to ensure that our current and future licensors obtain appropriate patent protection to all product candidates that we license from them. The patent prosecution process is expensive and time- consuming, and we and our licensors may not be able to file and prosecute all necessary or desirable patent applications at a reasonable cost or in a timely manner.

Our patent portfolio comprises three U.S. patents exclusively licensed to us from Bioprojet. One U.S. patent, No. 8,207,197 has claims directed to a polymorph, i.e. a specific crystalline form, of pitolisant and, methods for preparing that polymorph of pitolisant, which is expected to expire in February 2029 without taking into consideration any possible patent term extension. A second U.S. patent, No. 8,486,497, has claims directed to methods of treating excessive daytime sleepiness by administering pitolisant, which is expected to expire in September 2029 without taking into consideration any possible patent term extension. With all applicable patent term adjustments available and granted to us, the term of the last-to-expire pitolisant-related patent in our portfolio extends to September 2029.

The patents that we in-license now or the patents and patent applications that we own or in-license in the future may not have patentable claims that protect our current and future product candidates in the relevant jurisdictions where we intend to commercialize such products. There is no assurance that we and our licensor are aware of all potentially relevant prior art relating to future patent applications. As such, the patent examiner may find prior art that can prevent a patent from issuing from a pending patent application. During the patent examination process, we or our licensor may be required to narrow the pending claims to overcome prior art, a process that may limit the scope of patent protection. Even if patents do successfully issue based on our future patent applications, and even if the issued patents cover our current and future product candidates, including their compositions formulation, method of manufacture, and method of use, third parties may challenge our issued patents’ validity, enforceability or scope, which may result in such patents being narrowed, invalidated or held unenforceable. Any successful opposition to these patents or any other patents owned by or licensed to us in the future could deprive us of rights necessary for the successful commercialization of any of our current or future product candidates, if approved. Further, if we encounter delays in regulatory approvals, the period of time during which we could market a product candidate under patent protection could be reduced.

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If the patent applications we may own or in-license in the future with respect to our current and future product candidates fail to issue, if their breadth or strength of protection is threatened, or if they fail to provide meaningful exclusivity for any of our current or future product candidates, it could dissuade other companies from collaborating with us to develop future product candidates, and threaten our ability to commercialize our current and future product candidates. Notably, pending patent applications cannot be enforced against third parties practicing the technology claimed in such applications unless and until a patent issues from such applications. Any such outcome could have an adverse effect on our business.

The patent position of biotechnology and pharmaceutical companies generally is highly uncertain, involves complex legal and factual questions, and has in recent years been the subject of much litigation. In addition, the laws of foreign countries may not protect our rights to the same extent as the laws of the United States. For example, European patent law restricts the patentability of methods of treatment of the human body more than U.S. law does.

Publications of discoveries in scientific literature often lag behind the actual discoveries, and patent applications in the United States and other jurisdictions are typically not published until 18 months after filing, or in some cases not at all.

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Therefore, we cannot know with certainty whether we were the first to make the inventions claimed in our owned or licensed patents or pending patent applications, or that we were the first to file for patent protection of such inventions. As a result, the issuance, scope, validity, enforceability and commercial value of our patent rights are highly uncertain. Our future patent applications may not result in patents being issued which protect our technology or products, in whole or in part, or which effectively prevent others from commercializing competitive technologies and products. Changes in either the patent laws or interpretation of the patent laws in the United States and other countries may diminish the value of our patents or narrow the scope of our patent protection.

Patent reform legislation could increase the uncertainties and costs surrounding the prosecution of our patent applications and the enforcement or defense of our issued patents. On September 16, 2011, the Leahy-Smith America Invents Act (the “Leahy-Smith Act”) was signed into law. The Leahy-Smith Act made a number of significant changes to United States patent laws. These include provisions that affect the way patent applications are prosecuted and challenged at the USPTO and may also affect patent litigation. The USPTO has developed and continues to develop new regulations and procedures to govern administration of the Leahy-Smith Act, and many of the substantive changes to patent law associated with the Leahy-Smith Act, and in particular, the first to file provisions, only became effective on March 16, 2013. Accordingly, it remains unclear what impact the Leahy-Smith Act, subsequent rulemaking, and judicial interpretation of the Leahy-Smith Act and regulations will have on the operation of our business. However, the Leahy- Smith Act and its implementation could increase the uncertainties and costs surrounding the prosecution of our patent applications and the enforcement or defense of our issued patents, all of which could have an adverse effect on our business and financial condition. Moreover, future changes to the patent laws of the United States and foreign jurisdictions may adversely affect the term, scope, validity and enforceability of our or our licensor’s patent rights. For example, a new bill (Terminating the Extension of Rights Misappropriated Act, or TERM Act, H.R. 3199) percolating through the United States Congress aims to reduce the term of certain drug patents in order to ease generic entry and increase competition.

The inventorship and ownership rights for patents that we in-license or may own or in-license in the future may be challenged by third parties. Such challenges could result in loss of exclusive rights to such patents, which could limit our ability to stop others from using or commercializing similar or identical technology and products, or require us to obtain a license from such third parties on commercially reasonable terms to secure exclusive rights. If any such challenges to inventorship or ownership were asserted, there is no assurance that a court would find in our favor or that, if we choose to seek a license, such license would be available to us on acceptable terms or at all.

Moreover, we may be subject to a third-party pre-issuance submission of prior art to the USPTO or become involved in pre- and post-issuance opposition, derivation, re-examination, inter partes review, post-grant review or interference proceedings challenging our patent rights or the patent rights of others. An adverse determination in any such submission, proceeding or litigation could reduce the scope of, or invalidate, our patent rights, allow third parties to commercialize our technology or products and compete directly with us, without payment to us, or result in our inability to manufacture or commercialize products without infringing third-party patent rights. In addition, if the breadth or strength of protection provided by our patents and patent applications, whether owned or in-licensed now or in the future, is threatened, it could dissuade companies from collaborating with us to license, develop or commercialize current or future product candidates.

The issuance of a patent is not conclusive as to its inventorship, scope, validity or enforceability, and our licensed patents may be challenged in the courts or patent offices in the United States. Such challenges may

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result in loss of exclusivity or freedom to operate or in patent claims being narrowed, invalidated or held unenforceable, in whole or in part, which could limit our ability to stop others from using or commercializing similar or identical technology and products, or limit the duration of the patent protection of our technology and products. Moreover, patents have a limited lifespan. In the United States, the natural expiration of a patent is generally 20 years after the filing of the earliest non-provisional application to which the patent claims priority. Various extensions may be available; however, the life of a patent, and the protection it affords, is limited. We may be required to disclaim a portion of patent term in order to overcome double patenting rejections from the patent office, thus potentially shortening our exclusivity period. Without patent protection for our current or future product candidates, we may be open to competition from generic versions of such products. Given the amount of time required for the development, testing and regulatory review of new product candidates, patents protecting such candidates might expire before or shortly after such candidates are commercialized. As a result, our licensed patent portfolio may not provide us with sufficient rights to exclude others from commercializing products similar or identical to ours.

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If we fail to comply with our obligations under any license, collaboration or other agreements, we may be required to pay damages and could lose intellectual property rights that are necessary for developing and protecting our current and future product candidates.

We have licensed certain intellectual property rights covering pitolisant from Bioprojet, and we may license intellectual property rights from others in the future. If, for any reason, our license agreement with Bioprojet or any future licensor is terminated or we otherwise lose the rights associated with a license, it could adversely affect our business. Our license agreement with Bioprojet imposes, and any future collaboration agreements or license agreements we enter into are likely to impose various development, commercialization, funding, milestone, royalty, diligence, sublicensing, insurance, patent prosecution and enforcement or other obligations on us. If we breach any material obligations, or use the intellectual property licensed to us in an unauthorized manner, we may be required to pay damages and the licensor may have the right to terminate the license, which could result in us being unable to develop, manufacture and sell products that are covered by the licensed technology, or having to negotiate new or reinstated licenses on less favorable terms, or enable a competitor to gain access to the licensed technology.

If we do not obtain protection under the Hatch-Waxman Amendments by extending the patent term for our current and future product candidates, our business may be harmed.

Our commercial success will largely depend on our licensor’s ability to obtain and maintain patent and other intellectual property in the United States for pitolisant, and our target indications, and our ability to maintain obtain and maintain patent and other intellectual property in the United States for any product candidates. Given the amount of time required for the development, testing and regulatory review of new product candidates, patents protecting product candidates might expire before or shortly after such candidates begin to be commercialized. We expect to seek extensions of patent terms in the United States.

Depending upon the timing, duration and specifics of FDA marketing approval of our current and future product candidates, one or more of our U.S. patents may be eligible for limited patent term restoration under the Drug Price Competition and Patent Term Restoration Act of 1984, referred to as the Hatch-Waxman Amendments. The Hatch-Waxman Amendments permit a patent restoration term of up to five years beyond the normal expiration of the patent as compensation for patent term lost during drug development and the FDA regulatory review process, which is limited to the approved indication (or any additional indications approved during the period of extension). This extension is limited to only one patent that covers the approved product, the approved use of the product, or a method of manufacturing the product. However, the applicable authorities, including the FDA and the USPTO in the United States, and any equivalent regulatory authority in other countries, may not agree with our assessment of whether such extensions are available, and may refuse to grant extensions to our patents, or may grant more limited extensions than we request. We may not be granted an extension because of, for example, failing to apply within applicable deadlines, failing to apply prior to expiration of relevant patents or otherwise failing to satisfy applicable requirements. Moreover, the applicable time-period or the scope of patent protection afforded could be less than we request.

If we or our licensor are unable to extend the expiration date of our or their existing patents or obtain new patents with longer expiry dates, as applicable, our competitors may be able to take advantage of our investment in development and clinical trials by referencing our clinical and preclinical data to obtain approval of competing products following our patent expiration and launch their product earlier than might otherwise be the case.

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The validity, scope and enforceability of any patents listed in the Orange Book that cover our current and future product candidates can be challenged by third parties.

One or more third parties may challenge the current patents, or future patents within our portfolio, which could result in the invalidation of, or render unenforceable, some or all of the relevant patent claims or a finding of non-infringement. For example, if a third party files an ANDA for a generic drug containing pitolisant, and relies in whole or in part on studies conducted by or for us, the third party will be required to certify to the FDA that either: (1) there is no patent information listed in the FDA’s Orange Book with respect to our NDA for the applicable approved product candidate; (2) the patents listed in the Orange Book have expired; (3) the listed patents have not expired, but will expire on a particular date and approval is sought after patent expiration; or (4) the listed patents are invalid or will not be infringed by the manufacture, use or sale of the third party’s generic drug. A certification that the new drug will not infringe the Orange Book-listed patents for the applicable approved product candidate, or that such patents are invalid, is called a paragraph IV certification. If the third party submits a paragraph IV certification to the FDA, a notice of the paragraph IV certification must also be sent to us

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once the third party’s ANDA is accepted for filing by the FDA. We may then initiate a lawsuit to defend the patents identified in the notice. The filing of a patent infringement lawsuit within 45 days of receipt of the notice automatically prevents the FDA from approving the third party’s ANDA until the earliest of 30 months or the date on which the patent expires, the lawsuit is settled, or the court reaches a decision in the infringement lawsuit in favor of the third party. If we do not file a patent infringement lawsuit within the required 45-day period, the third party’s ANDA will not be subject to the 30-month stay of FDA approval.

Moreover, a third party may challenge the current patents, or future patents within our portfolio, which could result in the invalidation of some or all of the patents that might otherwise be eligible for listing in the Orange Book for one of our products. If a third party successfully challenges all of the patents that might otherwise be eligible for listing in the Orange Book for one of our products, we will not be entitled to the 30-month stay of FDA approval upon the filing of an ANDA for a generic drug containing, for example, pitolisant, and relies in whole or in part on studies conducted by or for us.

Litigation or other proceedings to enforce or defend intellectual property rights are often very complex in nature, may be very expensive and time-consuming, may divert our management’s attention from our core business, and may result in unfavorable results that could limit our ability to prevent third parties from competing with our current and future product candidates.

Obtaining and maintaining our patent protection depends on compliance with various procedural, document submission, fee payment and other requirements imposed by governmental patent agencies, and our patent protection could be reduced or eliminated for noncompliance with these requirements.

Periodic maintenance fees on any issued patent are due to be paid to the USPTO and other foreign patent agencies in several stages over the lifetime of the patent. The USPTO and various foreign national or international patent agencies require compliance with a number of procedural, documentary, fee payment and other similar provisions during the patent application process. While an inadvertent lapse can in many cases be cured by payment of a late fee or by other means in accordance with the applicable rules, there are situations in which noncompliance can result in abandonment or lapse of the patent or patent application, resulting in partial or complete loss of patent rights in the relevant jurisdiction. Noncompliance events that could result in abandonment or lapse of patent rights include, but are not limited to, failure to timely file national and regional stage patent applications based on our international patent application, failure to respond to official actions within prescribed time limits, non-payment of fees and failure to properly legalize and submit formal documents. If we or our licensors fail to maintain patents and patent applications, whether owned or in-licensed now or in the future, covering any of our current or future product candidates, our competitors might be able to enter the market, which would have an adverse effect on our business.

We may need to acquire or license intellectual property from third parties, and such licenses may not be available or may not be available on commercially reasonable terms.

A third party may hold intellectual property, including patent rights that are important or necessary to the development of our current and future product candidates. It may be necessary for us to use the patented or proprietary technology of one or more third parties to commercialize our current and future product candidates. If we are unable to acquire such intellectual property outright, or obtain licenses to such intellectual property from such third parties when needed or on commercially reasonable terms, our ability to commercialize our current and future product candidates, if approved, would likely be delayed.

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The risks described elsewhere pertaining to our intellectual property rights also apply to the intellectual property rights that we in-license, and any failure by us or our licensors to obtain, maintain, defend and enforce these rights could have an adverse effect on our business. In some cases we may not have control over the prosecution, maintenance or enforcement of the patents that we license, and may not have sufficient ability to provide input into the patent prosecution, maintenance and defense process with respect to such patents, and our licensors may fail to take the steps that we believe are necessary or desirable in order to obtain, maintain, defend and enforce the licensed patents.

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Third-party claims or litigation alleging infringement of patents or other proprietary rights, or seeking to invalidate patents or other proprietary rights, may delay or prevent the development and commercialization of any of our current or future product candidates.

Our commercial success depends in part on our avoiding infringement and other violations of the patents and proprietary rights of third parties. There is a substantial amount of litigation, both within and outside the United States, involving patent and other intellectual property rights in the pharmaceutical and biotechnology industries, including patent infringement lawsuits, interferences, derivation and administrative law proceedings, inter partes review and post-grant review before the USPTO, as well as oppositions and similar processes in foreign jurisdictions. Numerous United States and foreign issued patents and pending patent applications, which are owned by third parties, exist in the fields in which we are or may in the future be developing product candidates. As the biotechnology and pharmaceutical industries expand and more patents are issued, and as we gain greater visibility and market exposure as a public company, the risk increases that our product candidates or other business activities may be subject to claims of infringement of the patent and other proprietary rights of third parties.

Third parties may assert that we are infringing their patents or employing their proprietary technology without authorization.

There may be third-party patents or patent applications with claims to materials, formulations, methods of manufacture or methods for treatment related to the use or manufacture of our current and future product candidates. Because patent applications can take many years to issue, there may be currently pending patent applications that may later result in issued patents that our current and future product candidates may infringe. In addition, third parties may obtain patents in the future and claim that use of our technologies infringes upon these patents. If any third-party patents were held by a court of competent jurisdiction to cover the manufacturing process of any of our current and future product candidates, any molecules formed during the manufacturing process or any final product itself, the holders of any such patents may be able to block our ability to commercialize such product candidate unless we obtained a license under the applicable patents, or until such patents expire. Similarly, if any third-party patent was to be held by a court of competent jurisdiction to cover aspects of our formulations, processes for manufacture or methods of use, including combination therapy, the holders of any such patent may be able to block our ability to develop and commercialize the applicable product candidate unless we obtained a license or until such patent expires. In either case, such a license may not be available on commercially reasonable terms or at all. In addition, we may be subject to claims that we are infringing other intellectual property rights, such as trademarks or copyrights, or misappropriating the trade secrets of others, and to the extent that our employees, consultants or contractors use intellectual property or proprietary information owned by others in their work for us, disputes may arise as to the rights in related or resulting know-how and inventions.

Parties making claims against us may obtain injunctive or other equitable relief, which could effectively block our ability to further develop and commercialize our current and future product candidates. Defense of these claims, regardless of their merit, would involve substantial litigation expense and would be a substantial diversion of employee resources from our business. In the event of a successful infringement or other intellectual property claim against us, we may have to pay substantial damages, including treble damages and attorneys’ fees for willful infringement, obtain one or more licenses from third parties, pay royalties or redesign our affected products, which may be impossible or require substantial time and monetary expenditure. We cannot predict whether any such license would be available at all or whether it would be available on commercially reasonable terms. Furthermore, even in the absence of litigation, we may need to obtain licenses from third parties to advance our research or allow commercialization of our current and future product candidates, and we have done so from time to time. We may fail to obtain any of these licenses at a reasonable cost or on reasonable terms, if at all. In that event, we would be unable to further develop and commercialize our current and future product candidates, which could harm our business significantly. Claims that we have misappropriated the confidential information or trade secrets of third parties could have a similar negative impact on our business.

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We cannot provide any assurances that third-party patents do not exist which might be enforced against our current and future product candidates, resulting in either an injunction prohibiting our sales, or, with respect to our sales, an obligation on our part to pay royalties or other forms of compensation to third parties.

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We may not identify relevant third-party patents or may incorrectly interpret the relevance, scope or expiration of a third-party patent, which might adversely affect our ability to develop and market our products.

We cannot guarantee that any of our patent searches or analyses, including the identification of relevant patents, the scope of patent claims or the expiration of relevant patents, are complete or thorough, nor can we be certain that we have identified each and every third-party patent and pending application in the United States and abroad that is relevant to or necessary for the commercialization of our current product candidate in any jurisdiction.

It is possible that we and our current and future licensors will fail to identify patentable aspects of research and development output before it is too late to obtain patent protection. The patent applications that we may own or in-license in the future may fail to result in issued patents with claims that cover our current and future product candidates. We and our current and future licensors may also inadvertently make statements to regulatory agencies during the regulatory approval process that may be inconsistent with positions that have been taken during prosecution of the patent applications, which may result in such patents being narrowed, invalidated or held unenforceable.

The scope of a patent claim is determined by an interpretation of the law, the written disclosure in a patent and the patent’s prosecution history. Our interpretation of the relevance or the scope of a patent or a pending application may be incorrect, which may negatively affect our ability to market our products. We may incorrectly determine that our products are not covered by a third-party patent or may incorrectly predict whether a third party’s pending application will issue with claims of relevant scope. Our determination of the expiration date of any patent in the United States or abroad that we consider relevant may be incorrect, and our failure to identify and correctly interpret relevant patents may negatively affect our ability to develop and market our products.

We may become involved in lawsuits to protect or enforce our patents, the patents of our licensors or our other intellectual property rights, which could be expensive, time consuming and unsuccessful.

Competitors may infringe or otherwise violate the patents of our licensor or our other intellectual property rights. To counter infringement or unauthorized use, we may be required to file legal claims, which can be expensive and time-consuming. In addition, in an infringement proceeding, a court may decide that an asserted patent is not valid or is unenforceable, or may refuse to stop the other party from using the technology at issue on the grounds that the asserted patent does not cover the technology in question. An adverse result in any litigation or defense proceedings could put one or more of asserted patents at risk of being invalidated or interpreted narrowly and could put a related patent application at risk of not issuing. The initiation of a claim against a third party may also cause the third party to bring counter claims against us such as claims asserting that our patents are invalid or unenforceable. In patent litigation in the United States, defendant counterclaims alleging invalidity or unenforceability are commonplace. Grounds for a validity challenge could be an alleged failure to meet any of several statutory requirements, including lack of novelty, obviousness, non-enablement or lack of statutory subject matter. Grounds for an unenforceability assertion could be an allegation that someone connected with prosecution of the patent withheld relevant material information from the USPTO, or made a materially misleading statement, during prosecution. Third parties may also raise similar validity claims before the USPTO in post-grant proceedings such as ex parte re-examinations, inter partes review, or post-grant review, or oppositions or similar proceedings outside the United States, in parallel with litigation or even outside the context of litigation. The outcome following legal assertions of invalidity and unenforceability is unpredictable. We cannot be certain that there is no invalidating prior art, of which we and the patent examiner were unaware during prosecution. For the patents and patent applications that we may license in the future, we may have limited or no right to participate in the defense of any licensed patents against challenge by a third party. If a defendant were to prevail on a legal assertion of invalidity or unenforceability, we would lose at least part, and perhaps all, of any future patent protection on our current or future product candidates. Such a loss of patent protection could harm our business.

We may not be able to detect or prevent, alone or with our licensors, misappropriation of our intellectual property rights, particularly in countries where the laws may not protect those rights as fully as in the United States. Our business could be harmed if in litigation the prevailing party does not offer us a license on

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commercially reasonable terms. Any litigation or other proceedings to enforce our intellectual property rights may fail, and even if successful, may result in substantial costs and distract our management and other employees.

Even if we establish infringement, the court may decide not to grant an injunction against further infringing activity and instead award only monetary damages, which may or may not be an adequate remedy. Furthermore, because of the substantial amount of discovery required in connection with intellectual property litigation, there is a risk that some of our

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confidential information could be compromised by disclosure during this type of litigation. There could also be public announcements of the results of hearings, motions or other interim proceedings or developments. If securities analysts or investors perceive these results to be negative, it could have an adverse effect on the price of our common shares.

Because of the expense and uncertainty of litigation, we may not be in a position to enforce our intellectual property rights against third parties.

Because of the expense and uncertainty of litigation, we may conclude that even if a third party is infringing our in-licensed patents, any patents that may be issued as a result of our future patent applications, or other intellectual property rights, the risk-adjusted cost of bringing and enforcing such a claim or action may be too high or not in the best interest of our company or our shareholders. In such cases, we may decide that the more prudent course of action is to simply monitor the situation or initiate or seek some other non-litigious action or solution.

Changes in U.S. patent law or the patent law of other countries or jurisdictions could diminish the value of patents in general, thereby impairing our ability to protect our products.

The United States has recently enacted and implemented wide-ranging patent reform legislation. The U.S. Supreme Court and the U.S. Court of Appeals for the Federal Circuit have issued numerous precedential opinions in recent years narrowing the scope of patent protection available in certain circumstances or weakening the rights of patent owners in certain situations. In addition to increasing uncertainty with regard to our ability to obtain patents in the future, this combination of events has created uncertainty with respect to the value of patents, once obtained. Depending on actions by the U.S. Congress, the federal courts and the USPTO, the laws and regulations governing patents could change in unpredictable ways that would weaken our ability to obtain new patents or to enforce patents that we have licensed or that we might obtain in the future. Similarly, changes in patent law and regulations in other countries or jurisdictions or changes in the governmental bodies that enforce them or changes in how the relevant governmental authority enforces patent laws or regulations may weaken our ability to obtain new patents or to enforce patents that we have licensed or that we may obtain in the future.

The U.S. federal government retains certain rights in inventions produced with its financial assistance under the Bayh-Dole Act. The federal government retains a “nonexclusive, non-transferable, irrevocable, paid-up license” for its own benefit. The Bayh-Dole Act also provides federal agencies with “march-in rights.” March-in rights allow the government, in specified circumstances, to require the contractor or successors in title to the patent to grant a “nonexclusive, partially exclusive, or exclusive license” to a “responsible applicant or applicants.” If the patent owner refuses to do so, the government may grant the license itself.

We may be subject to claims that our employees, consultants or independent contractors have wrongfully used or disclosed confidential information of their former employers or other third parties.

We employ individuals who were previously employed at other biotechnology or pharmaceutical companies. Although we seek to protect our ownership of intellectual property rights by ensuring that our agreements with our employees, collaborators and other third parties with whom we do business include provisions requiring such parties to assign rights in inventions to us, we may be subject to claims that we or our employees, consultants or independent contractors have inadvertently or otherwise used or disclosed confidential information of our employees’ former employers or other third parties. We may also be subject to claims that former employers or other third parties have an ownership interest in our future patents. Litigation may be necessary to defend against these claims. There is no guarantee of success in defending these claims, and if we fail in defending any such claims, in addition to paying monetary damages, we may lose valuable intellectual property rights, such as exclusive ownership of, or right to use, valuable intellectual property. Even if we are successful, litigation could result in substantial cost and be a distraction to our management and other employees. Moreover, any such litigation or the threat thereof may adversely affect our reputation, our ability to form strategic alliances or sublicense our rights to collaborators, engage with scientific advisors or hire

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employees or consultants, each of which would have an adverse effect on our business, results of operations and financial condition.

In addition, while it is our policy to require our employees and contractors who may be involved in the development of intellectual property to execute agreements assigning such intellectual property to us, we may be unsuccessful in executing such an agreement with each party who in fact develops intellectual property that we regard as our own. Our and their assignment agreements may not be self- executing or may be breached, and we may be forced to bring claims against

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third parties, or defend claims they may bring against us, to determine the ownership of what we regard as our intellectual property.

If we or our licensors fail in prosecuting or defending any such claims, in addition to paying monetary damages, we may lose valuable intellectual property rights or personnel. Even if we and our licensors are successful in prosecuting or defending against such claims, litigation could result in substantial costs and be a distraction to management.

Any trademarks we have obtained or may obtain may be infringed or be successfully challenged, resulting in harm to our business.

We expect to rely on trademarks as one means to distinguish any of our current and future product candidates that are approved for marketing from the products of our competitors. For example, we are marketing pitolisant for the treatment of EDS or cataplexy in adult patients with narcolepsy under the brand name WAKIX, which we have licensed from Bioprojet. We may design or create new trademarks and apply to register them, our trademark applications may not be approved in the United States or any relevant foreign jurisdiction. Third parties may oppose or attempt to cancel our trademark applications or trademarks, or otherwise challenge our use of the trademarks. In the event that our trademarks are successfully challenged, we could be forced to rebrand our drugs, which could result in loss of brand recognition and could require us to devote resources to advertising and marketing new brands. Our competitors may infringe our trademarks and we may not have adequate resources to enforce our trademarks. If we attempt to enforce our trademarks and assert trademark infringement claims, a court may determine that the marks we have asserted are invalid or unenforceable, or that the party against whom we have asserted trademark infringement has superior rights to the marks in question. In this case, we could ultimately be forced to cease use of such trademarks.

Risks Related to Being a Public CompanyOwnership of our Common Stock

We will incur increased costsno longer qualify as a result of operating as a public company,an “emerging growth company” and our management will be required to devote substantial time to compliancecomply with our public company responsibilities and corporate governance practices.

As a public company, and particularly after we arecertain provisions of the Sarbanes-Oxley Act. We can no longer an “emerging growth company,” we will incur significant legal, accounting and other expenses that we did not incur as a private company. The Sarbanes-Oxley Acttake advantage of 2002 (the “Sarbanes Oxley Act”), the Dodd-Frank Wall Street Reform and Consumer Protection Act, the listing requirements of Nasdaq and other applicable securities rules and regulations impose various requirements on public companies. Our management and other personnel will need to devote a substantial amount of time to compliance with these requirements. Moreover, these rules and regulations will increase our legal and financial compliance costs and will make some activities more time-consuming and costly. If, notwithstanding our efforts to comply with new or changing laws, regulations and standards, we fail to comply, regulatory authorities may initiate legal proceedings against us, and our business may be harmed. Further, failure to comply with these laws, regulations and standards may make it more difficult and more expensive for us to obtain directors’ and officers’ liability insurance, which could make it more difficult for us to attract and retain qualified members to serve on our board of directors or committees or as members of senior management. We cannot predict or estimate the amount of additional costs we will incur as a public company or the timing of such costs.

As a result of becoming a public company, we will be obligated to develop and maintain proper and effective internal controls over financial reporting and any failure to maintain the adequacy of these internal controls may adversely affect investor confidence in our company and, as a result, the value of our common shares.

We will be required, pursuant to Section 404 of the Sarbanes Oxley Act (“Section 404”), to furnish a report by management on, among other things, the effectiveness of our internal controls over financial reporting for the fiscal year beginning January 1, 2022. This assessment will need to include disclosure of any material

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weaknesses identified by our management in our internal controls over financial reporting. Our independent registered public accounting firm will not be required to attest to the effectiveness of our internal controls over financial reporting until our first annual report required to be filed with the SEC following the date we are no longer an emerging growth company, as defined in the JOBS Act. At such time as we are required to obtain auditor attestation, if we then have a material weakness, we would receive an adverse opinion regarding our internal control over financial reporting from our independent registered public accounting firm. We will be required to disclose significant changes made in our internal controls procedures on a quarterlybasis.

We are beginning the costly and challenging process of compiling the system and processing documentation necessary to perform the evaluation needed to comply with Section 404, and we may not be able to complete our evaluation, testing and any required remediation in a timely fashion. Our compliance with Section 404 will require that we incur substantial legal, accounting and other compliance expense and expend significant management efforts. We currently do not have an internal audit group, and we will need to hire additional accounting and finance staff and consultants with appropriate public company experience and technical accounting knowledge and compile the system and process documentation necessary to perform the evaluation needed to comply with Section 404.

During the evaluation and testing process of our internal controls, if we identify one or more material weaknesses in our internal controls over financial reporting, we will be unable to assert that our internal controls over financial reporting are effective. We cannot assure you that there will not be material weaknesses or significant deficiencies in our internal controls over financial reporting in the future. Any failure to maintain effective internal controls over financial reporting could severely inhibit our ability to accurately report our financial condition or results of operations. If we are unable to conclude that our internal controls over financial reporting is effective, or if our independent registered public accounting firm determines we have a material weakness or significant deficiency in our internal controls over financial reporting, we could lose investor confidence in the accuracy and completeness of our financial reports, the market price of our common shares could decline, and we could be subject to sanctions or investigations by Nasdaq, the SEC or other regulatory authorities. Failure to remedy any material weakness in our internal controls over financial reporting, or to implement or maintain other effective control systems required of public companies, could also negatively impact our ability to access to the capital markets.

In addition, effective disclosure controls and procedures enable us to make timely and accurate disclosure of financial and non-financial information that we are required to disclose. As a public company, if our disclosure controls and procedures are ineffective, we may be unable to report our financial results or make other disclosures accurately on a timely basis, which could cause our reported financial results or other disclosures to be materially misstated and result in the loss of investor confidence and cause the market price of our common shares to decline. If we were to subsequently elect instead to comply with these public company effective dates, such election would be irrevocable pursuant to the JOBS Act.

We are an emerging growth company and we cannot be certain if the reduced disclosure requirements applicable to emerging growth companies will makecompanies.

Based on the market value of our common stock less attractive to investors.

We areheld by non-affiliates as of June 30, 2021, we no longer qualify as an “emerging growth company” as defined in the JOBS Act. Under the JOBSJumpstart Our Business Startups Act emerging growth companies can delay adopting new or revised accounting standards until such time(the “JOBS Act”), as those standards applyof December 31, 2021. As a result, we may incur additional and increasing costs to private companies. We have electedcomply with our reporting and other obligations that we had not historically incurred due to use this exemption from new or revised accounting standards and, therefore, we will not be subject to the same new or revised accounting standardsour status as other public companies that have not made this election.

For as long as we continue to be an emerging growth company we also intendor as a smaller reporting company. These costs include (i) being required to take advantagecomply with the auditor attestation requirements of certain other exemptions from various reporting requirements that are applicable to other public companies including, but not limited to, reducedSection 404, (ii) increased disclosure obligations regarding executive compensation in our periodic reports and proxy statements, and exemptions from the(iii) requirements of holding a non-bindingnonbinding advisory vote on executive compensation and stockholder approval of any golden parachute payments not previously approved. We cannot predict if investors will find our common stock less attractive because we will rely on these exemptions. If some investors find our common stock less attractive as a result, there may be a less active trading market for our common stock and our stock price may be more volatile.

We will remain an emerging growth company until the earliest of (i) the last day of the fiscal year in which we have total annual gross revenue of $1.07 billion or more; (ii) the last day of the fiscal year following the fifth anniversary of the date of the closing of our IPO; (iii) the date on which we have issued more than $1.0

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billion in nonconvertible debt during the previous three fiscal years; or (iv) the date on which we are deemed to be a “large accelerated filer” under the rules of the SEC.

Our management team has limited experience managing a public company.

Our chief executive officer does not have experience managing a public company, interacting with public company investors or complying with the increasingly complex laws pertaining to public companies. Our management team, as a whole, may not successfully or efficiently manage the transition to being a public company subject to significant regulatory oversight and reportingThese additional obligations under the federal securities laws and the continuous scrutiny of securities analysts and investors. These new obligations and constituents will require significant attention from our senior management, particularly from our chief executive officer,us to dedicate internal resources, engage outside consultants, and could divert their attention away fromadopt a detailed work plan to assess and document the day-to-day managementadequacy of our business, which could adversely affect our revenue, business, results of operationsinternal controls over financial reporting, continue steps to improve control processes, as appropriate, validate through testing that controls are functioning as documented, and implement a continuous reporting and improvement process for internal controls over financial condition.

Risks Related to Ownership of our Common Stockreporting.

Our directors, officers and principal stockholders beneficially own a significant percentage of our stock and will be able to exert significant control over matters subject to stockholder approval.

As of December 31, 2020,2021, our directors, officers, five percent or greater stockholders, and their respective affiliates beneficially owned in the aggregate approximately 80%71% of our outstanding voting stock. As a result, these stockholders have the ability to influence us through this ownership position. These stockholders may be able to determine all matters requiring stockholder approval. For example, these stockholders may be able to control elections of directors, amendments of our organizational documents, and approval of any merger, sale of assets or other major corporate transaction. This may prevent or discourage unsolicited acquisition proposals or offers for our common stock that you may feel are in your best interest as one of our stockholders.

Future sales of our common stock in the public market, including sales by our directors, officers, or significant shareholders, could cause our share price to fall.

Sales of a substantial number of shares of our common stock in the public market or the perception that these sales might occur could depress the market price of our common stock and could impair our ability to raise capital through the

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sale of additional equity securities. Certain holders of our common stock are entitled to rights with respect to registration of such shares under the Securities Act pursuant to a registration rights agreement between such holders and us. If such holders, by exercising their registration rights, sell a large number of shares, they could adversely affect the market price for our common stock. Subject to compliance with applicable securities laws, our officers, directors and other shareholders and their respective affiliates may sell some or all of their common shares in the future. No prediction can be made as to the effect, if any, such future sales will have on the market price of the common shares prevailing from time to time.

If securities or industry analysts do not publish research or publish unfavorable research about our business, our stock price and trading volume could decline.

The trading market for our common stock will be influenced by the research and reports that industry or securities analysts publish about us or our business. If one or more of these analysts ceases coverage of our company or fails to publish reports on us regularly, we could lose visibility in the financial markets, which in turn could cause our stock price or trading volume to decline. Moreover, if our operating results do not meet the expectations of the investor community, one or more of the analysts who cover our company may change their recommendations regarding our company, and our stock price could decline.

Our quarterly operating results may fluctuate significantly.

We expect our operating results to be subject to quarterly fluctuations. Our net lossincome and other operating results will be affected by numerous factors, including:

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If our quarterly operating results fall below the expectations of investors or securities analysts, the price of our common stock could decline substantially. Furthermore, any quarterly fluctuations in our operating results may, in turn, cause the price of our stock to fluctuate substantially.

An active trading market for our common stock may not be maintained.

Our common stock only recently began trading on the Nasdaq Global Market, and we can provide no assurance that we will be able to maintain an active trading market on The Nasdaq Global Market or any other exchange in the future. If an active trading market for our common stock is not maintained, or if we fail to satisfy the continued listing standards of The Nasdaq Global Market for any reason and our common stock is delisted, it may be difficult for our stockholders to sell shares without depressing the market price for the shares or at all. An inactive market may also impair our ability to raise capital by selling shares and may impair our ability to acquire other companies or technologies by using our shares as consideration.

Future sales and issuances of our common stock or rights to purchase our common stock, including pursuant to our equity incentive plans, could result in additional dilution of the percentage ownership of our stockholders and could cause the stock price of our common stock to decline.

In the future, we may sell common stock, convertible securities or other equity securities in one or more transactions at prices and in a manner we determine from time to time. We also expect to issue common stock to employees, consultants and directors pursuant to our equity incentive plans. If we sell common stock, convertible securities or other equity securities in subsequent transactions, or common stock is issued pursuant to equity incentive plans, investors may be materially diluted. New investors in such subsequent transactions could gain rights, preferences and privileges senior to those of holders of our common stock.

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We have never declared or paid any dividends on our common stock and do not intend to pay any dividends in the foreseeable future. We anticipate that we will retain all of our future earnings for use in the operation of our business and for general corporate purposes. Any determination to pay dividends in the future will be at the discretion of our board of directors. Accordingly, investors must rely on sales of their common stock after price appreciation, which may never occur, as the only way to realize any future gains on their investments. Furthermore, we are party to a Credit Agreement with OrbiMed that contains negative covenants that limit our ability to pay dividends.

Our charter documents and Delaware law could prevent a takeover that stockholders consider favorable and could also reduce the market price of our stock.

Our amended and restated certificate of incorporation and our amended and restated bylaws contain provisions that could delay or prevent a change in control of our company. These provisions could also make it more difficult for stockholders to elect directors and take other corporate actions. These provisions include:

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These provisions may frustrate or prevent any attempts by our stockholders to replace or remove our current management by making it more difficult for stockholders to replace members of our board of directors, which is responsible for appointing the members of our management.

In addition, we are subject to the anti-takeover provisions contained in Section 203 of the Delaware General Corporation Law (the “DGCL”). Under Section 203 of the DGCL, a corporation may not, in general, engage in a business combination with any holder of 15% or more of its capital stock unless the holder has held the stock for three years or, among other exceptions, the board of directors has approved the transaction.

These and other provisions in our amended and restated certificate of incorporation and our amended and restated bylaws and under Delaware law could discourage potential takeover attempts, reduce the price investors might be willing to pay in the future for shares of our common stock and result in the market price of our common stock being lower than it would be without these provisions.

Our amended and restated certificate of incorporation provides that the Court of Chancery of the State of Delaware will be the exclusive forum for substantially all disputes between us and our stockholders, which could limit our stockholders’ ability to obtain a favorable judicial forum for disputes with us or our directors, officers or employees.

Our amended and restated certificate of incorporation provides that the Court of Chancery of the State of Delaware is the exclusive forum for:

Our stockholders are deemed to have notice of and have consented to the provisions of our amended and restated certificate of incorporation related to choice of forum. This exclusive forum provision may limit a stockholder’s ability to bring a claim in a judicial forum that it finds favorable for disputes with us or our directors, officers, or other employees, which may discourage lawsuits against us and our directors, officers and other employees. If a court were to find the exclusive forum provision in our amended and restated certificate of incorporation to be inapplicable or unenforceable in an action, we may incur additional costs associated with resolving the dispute in other jurisdictions, which could seriously harm our business.

Claims for indemnification by our directors and officers may reduce our available funds to satisfy successful third-party claims against us and may reduce the amount of money available to us.

Our amended and restated certificate of incorporation and amended and restated bylaws provide that we will indemnify our directors and officers, in each case to the fullest extent permitted by Delaware law.

In addition, as permitted by Section 145 of the DGCL, our amended and restated bylaws and our indemnification agreements that we have entered into with our directors and officers provide that:

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