1 Novel Treatments for Neurodegenerative Conditions Multi-modal, disease-modifying therapies
DISCLAIMER Forward-Looking Statements—All statements in this presentation other than statements of historical facts, including statements regarding the proposed transaction with Gemphire Therapeutics, Inc. (“Gemphire”) and other contemplated transactions, expected future results of operations and financial position of NeuroBo, its business or strategy, the clinical development of its product candidates and its objectives for future operations, are forward-looking statements. The words “anticipates,” “believes,” “plans,” “expects,” “projects,” “future,” “intends,” “may,” “will,” “should,” “could,” “estimates,” “predicts,” “potential,” “continue,” “guidance,” and similar expressions are intended to identify these forward-looking statements. Such forward-looking statements are based on expectations and involve risks, uncertainties and assumptions, including, without limitation: the risk that conditions to closing the proposed transaction are not satisfied, risks related to Gemphire’s ability to correctly estimate and manage its expenses, the risk that as a result of adjustments to the exchange ratio, Gemphire stockholders or NeuroBo stockholders could own more or less of the combined company than anticipated, the risk that the conditions to payment under the CVRs will not be met and that the CVRs may otherwise never deliver any value to Gemphire stockholders, risks related to the timing of completion of and availability of data from NeuroBo’s planned clinical trials, the clinical utility, potential benefits and market acceptance of NeuroBo’s product candidates, developments relating to NeuroBo’s competitors and its industry, the impact of government laws and regulations, NeuroBo’s ability to protect its intellectual property position, the strength of NeuroBo’s intellectual property portfolio, the strength of NeuroBo’s financial position, and changes in NeuroBo’s capital resource requirements. Consequently, actual results may differ materially from those expressed or implied in the statements. New risks emerge from time to time and it is not possible to predict all such factors. Forward-looking statements included in this presentation are based on information available to Gemphire and NeuroBo as of the date of this presentation. Neither Gemphire nor NeuroBo undertakes any obligation to update such forward-looking statements to reflect events or circumstances after the date of this presentation. Market and Statistical Data—This presentation contains estimates and other statistical data made by independent parties and by NeuroBo relating to market size and growth and other data about NeuroBo’s industry. This data involves assumptions and limitations, and you are cautioned not to give undue weight to such estimates and statistical data. Neither NeuroBo nor any other person makes any representation as to the accuracy or completeness of such data or undertakes any obligation to update such data after the date of this presentation. 2
ADDITIONAL INFORMATION & WHEREYOU CAN FIND IT Important Additional Information Will be Filed with the SEC. In connection with the proposed transaction, Gemphire intends to file relevant materials with the SEC, including a registration statement on Form S-4 that will contain a proxy statement/prospectus/information statement. GEMPHIRE URGES INVESTORS AND STOCKHOLDERS TO READ THESE MATERIALS CAREFULLY AND IN THEIR ENTIRETY WHEN THEY BECOME AVAILABLE BECAUSE THEY WILL CONTAIN IMPORTANT INFORMATION ABOUT GEMPHIRE, NEUROBO, THE PROPOSED TRANSACTION AND RELATED MATTERS. Investors and stockholders will be able to obtain free copies of the proxy statement/prospectus/information statement and other documents filed by Gemphire with the SEC (when they become available) through the website maintained by the SEC at www.sec.gov. In addition, investors and shareholders will be able to obtain free copies of the proxy statement/prospectus/information statement and other documents filed by Gemphire with the SEC by written request to Gemphire Therapeutics Inc., 17199 N. Laurel Park Drive, Suite 401, Livonia, MI 48152, Attention: Corporate Secretary. Investors and stockholders are urged to read the proxy statement/prospectus/information statement and the other relevant materials when they become available before making any voting or investment decision with respect to the proposed transaction. Participants in the Solicitation—Gemphire and NeuroBo, and each of their respective directors and executive officers and certain of their other members of management and employees, may be deemed to be participants in the solicitation of proxies in connection with Gemphire’s directors and executive officers is included in Gemphire’s Annual Report on Form 10-K for the year on March 18, 2019. Additional information regarding these persons and their interests in the transaction will be the proposed transaction. Information about ended December 31, 2018, filed with the SEC included in the proxy statement relating to the transaction when it is filed with the SEC. These documents can be obtained free of charge from the sources indicated above. No Offer or Solicitation—This presentation shall not constitute an offer to sell or the solicitation of an offer to sell or the solicitation of an offer to buy any securities, nor shall there be any sale of securities in any jurisdiction in which such offer, solicitation or sale would be unlawful prior to registration or qualification under the securities laws of any such jurisdiction. No public offer of securities shall be made except by means of a prospectus meeting the requirements of Section 10 of the Securities Act of 1933, as amended. 3
COMPANY SUMMARY C l i ni cal - s t ag e bi op h a r m a c e u t i ca l com pa n y w i t h t w o dr ug pr ogr a m s t o i m p ac t a r a n g e o f i n di c at i ons i n n eur odegener at i vedi s ease • • • NB-01: Phase 3-ready; targeting neuropathic pain (NP) NB-02: IND-ready; targeting Alzheimer’s and tauopathies Multi-modal with potential to be disease-modifying Drug Programs • Diabetic Neuropathic Pain (DNP), also known as Painful diabetic neuropathy (PDN) 8.4M people globally; current drugs have insufficient efficacy and are poorly tolerated Chemotherapy-induced peripheral neuropathy in cancer patients undergoing chemotherapy Alzheimer’s disease affects 10.6M people globally Tauopathies: rare diseases with no approved therapies affects • Therapeutic Focus • • • • • Series B financing of $24M in July 2019; $42M raised since inception Experienced executive team in drug development, innovation, and corporate strategy Reverse merger announced with Gemphire Therapeutics (Nasdaq: GEMP) in July 2019 Financing & Executive Leadership 4
NEUROBO DEVELOPMENT PIPELINE 5 CONFIDENTIAL INFORMATION Disease Indication Stage of Development Discovery Preclinical Phase I Phase 2 Phase 3 NB-01 (Ph III-ready) Painful Diabetic Neuropathy (PDN) Chemotherapy-induced Neuropathic Pain Other peripheral neuropathy NB-02 (IND-ready) Alzheimer’s Disease Tauopathies
NB-01 T ar get i n g neur o p a t h i c pai n F i r s t i n d ic a tio n :P DN 6
PAINFULDIABETIC NEUROPATHY OVERVIEW • PDN affects 8.4M people worldwide representing global drug sales of $3.05B (2018, GlobalData) • Diabetes and cancer are amongst the leading causes of neuropathic pain • Symptoms range from dull and tingling to debilitating pain; limiting mobility, negatively impacting sleep, and hindering glycemic control (Ormseth et al. 2011) • Current treatments show 30% reduction of pain in 40% of patients • Only three approved therapies for PDN with high rates of adverse events • When these fail, even in combination, physicians often turn to off-label use of opioids Significant market need: Safe, efficacious drugs with potential to modify underlying disease 7 Themostunmetneed is thereversal, ortreating thephysiopathology... Thisis achronic, incapacitating disease… - US Key Opinion Leader
PAINFUL DIABETIC NEUROPATHY (PDN) 2018 MARKET OVERVIEW FIRST INDICATION OF NB-01 Prevalence 8.4M 2.4M Drug Sales Global U.S. $3.1B $2.2B •Prevalence ofdiabetes •Majority of patientsare continues to increase globally 55-70yearsofage; PDN affects men and women equally •1/3of PDN patientsare refractorytocurrenttreatments 8 GlobalData PharmaPoint: Painful Diabetic Neuropathy, 2018
PDN PATIENT JOURNEY Confirmed painful diabetic neuropathy First Line • Pregabalin • Gabapentin • • Duloxetine Venlafaxine • Amitriptyline No Effect Partial Effect Second Line Or asses and combination therapy fail Third Line 9 Source: GlobalData, adapted from Callahan et al., 2012 ©GlobalData Opioids Tramadol Try another first-line drug If all three cl Try combination of first-line drugs Serotonin-norepinephrine reuptake inhibitors Tricyclic antidepressants Voltage-gated calcium channel 2 ligand
NB-01 TREATMENT PARADIGM Confirmed painful diabetic neuropathy NB-01 has thepotentialtoimprove first-linetherapysafety andeffectiveness 10 Source: GlobalData, adapted from Callahan et al., 2012 ©GlobalData NB-01
OUR DISTINCT, MULTI-TARGET APPROACH com pl ex pat hop h y si o l o g y • • N e u r opat hi c p ai n i s a m u l t i - t a r g e t di se a se w i t h a NB - 01 has di se a se - m o d i fy in g p o te n tia l with e ffe c ts o n m u l ti p le p a th wa y s and IL-6 End-Products • • Demonstrated effects on both pain alleviation and underlying pathways with extensive studies in rodent models Preclinical rodent models have also shown: - - - Improved nerve conduction velocity (NCV) Neurite outgrowth Reduction of thermal and mechanical hyperalgesia 11 Anti-inflammatory Reduction of TNF-Reducing cell damage Reduction of Advanced Glycation Nervegrowth and repair Elevation of Nerve Growth Factor (NGF)
12 NB-01 ACHIEVES MULTI-TARGET EFFECTS FROM COMBINED ACTION OF MULTIPLE COMPOUNDS IN ORAL FORMULATION Saponins (Glycosteroids) Anti-inflammatory effects Anti-neuroinflammatory Anti-oxidant effects effects Curcumins Reduction of Advanced Glycation End-Products Rosmarinic Acids • • • • 60 compounds isolated and characterized in drug Three structural classes as above correlated with product pharmacological activities related to PDN Dioscin (glycosteroid) and allantoin used as marker compounds Additional markers being developed for PK assays 121 CONFIDENTIAL INFORMATION
NB-01 ADHERES TO REQUIRED FDA DRUG GUIDELINES FOR NATURAL PRODUCT-BASED DRUGMIXTURES Clinicaltrialsofbotanical drugs areno more difficult thannon-botanical Sau (Larry) Lee, FDA, 2015 drugs Raw Material • Good Agricultural (GACP) in place Drug Substance (API) & Drug Product and Collection Practices • GMP-compliant manufacturing in two facilities in Korea Drug substance manufactured as paste Drug product manufactured as oral tablets QA/QC demonstrated with five batches; two external audits completed no issues NB-01 clinical-quality drug ready for human studies • Two external audits completed on Quality with no issues CMC and • • • • http://pqri.org/wp-content/uploads/2015/10/01-PQRI-Lee-Botanicals-20151.pdf Lee at al., Science 2015 Jan 16;347(6219 Suppl.):S32-4 13 CONFIDENTIAL INFORMATION
NB-01 DEMONSTRATED PAIN REDUCTION IN US PHASE 2 STUDY 16 US sites, 128 subjects, 3 doses vs. placebo (600mg and 300mg doses shown here) 3.5 * * * * * 2.5 Reduction from Baseline in NRS Score NRS: 11-point numeric scale* <0.05, <0.01 rating P values are baseline 1.5 0.5 0 1 2 3 4 5 6 7 8 9 10 11 12 Weeks 14 ClinicalTrials.gov NCT01822925 NB-01 600mg NB-01 300mg Placebo *****
NB-01 SHOWNTOBEWELL-TOLERATED INTWOPHASE2STUDIES: SAFETY & TOLERABILITY IS A SIGNIFICANT DIFFERENTIATOR Placebo NB-01 30% 25% Average incidence adverse events of 20% 15% ranges 15-30% over placebo of approved 10% treatments for PDN 5% 0% Constipation Sinusitis Headache Back pain Adverse events included = 2-3% difference in combined studies from placebo Safety data compiled from two Phase 2 studies (US and Korea) 15
PLANNED PHASE 2 STUDY: DEMONSTRATION OF EFFICACY & DISEASE MODIFICATION NB-01-203 (US) • Designed to demonstrate pain alleviation, effects on pathway potential disease modification biomarkers, and • 200 patient study with PDN • Single high dose of 600mg daily compared with placebo • Measurement of NRS pain scores in 12-week study • Measurement of biomarkers – cytokine panel, NGF, AGEs • Withdrawal of drug after 12 weeks to follow sustained effect of drug on pain alleviation 16
PHASE 3-READY STUDIES IN PDN PLANNED: POWERED FOR EFFICACY AND SAFETY NB-01-301 (US-NA) ANCHOR – PIVOTAL STUDY CSR TAL STUDY UDY • Two End of Phase 2 (EOP2) meetings completed with FDA • Endpoint: Change from baseline in weekly mean of daily pain scores 17 Year 1Year 2Year 3Year 4Year 5 Interim analysis results @ 1/3rd pts CSR Submit NDA rt-up NB-01-302 (OUS) BELAY – PIVO NB-01-303 CLIMB – EXTENSION SAFETY ST sta
NB-02 T a r g e t i ng A l z hei m er ’ s d i s e ase & T a u o pat hi es 18
ALZHEIMER’S &TAU-RELATED DISEASES (TAUOPATHIES) • Alzheimer’s disease affects 10.6M people globally (2016, Global Data) • Approved treatments focus on symptomatic management and largely on acetyl cholinesterase (AChE) inhibition • 650+ drug trials underway targeting Tau inhibition, amyloid plaque inhibition, and combinations with AChE inhibition • >20 diseases that result from tau protein aggregation in the brain; progressive supranuclear palsy (PSP) is a key focus • No current approved therapies for patients with tauopathies Significant opportunity forsafe, disease-modifying therapies that restore cognitive function 19 GlobalData PharmaPoint: Painful Diabetic Neuropathy, 2018
EXTENSIVE IND-READY PRECLINICAL STUDIES: NB-02 is a multi-component drug compound mixture designed to impact multiple pathways involved in neurodegenerative disease Extensive cognitive and behavioral pre-clinical studies Y-Maze, Morris Water Maze, and Novel Object Recognition studies show improved cognitive endpoints in transgenic mouse models IND-enabling toxicology studies completed 26-week rat toxicity, 39-week dog toxicity, and other IND requirements done 20
INTELLECTUAL PROPERTY PORTFOLIO • Granted patents in US, EU, and Asia on combination of plant species for drug composition – Expires 2027 • Granted patents in EU, Asia, and allowance in US for composition and use in peripheral neuropathy – Expires 2031 • Patents being prosecuted on other quality assays to extend patent life peripheral neuropathy indications and • Patents in prosecution for US, EU, degenerative neurological disease and Asia on composition for treating including Alzheimer’s – Expires 2035 • Patents in prosecution in US, EU, and Asia on method for treating neurological disease including Alzheimer’s – Expires 2035 21 NB-02 Drug Mixture Composition Neuro-degenerative disease NB-01 Drug Mixture Composition Peripheral Neuropathy
PROVEN LEADERSHIP TEAM John L. Brooks III, BBA, MSBA President & CEO Nandan Padukone, PhD, MBA SVP, Business Development Mark Versavel, MD, PhD, MBA Chief Medical Officer • • Experienced biotech, device, and healthcare executive Former President & CEO of Joslin Diabetes Center • • Experienced executive in innovation and venture development Former President & CEO of Nuvera Biosciences at MD Anderson Cancer Center • Senior medical and clinical drug development experience Former Vice President of CNS, Clinical Development, and Medical Affairs at Sunovion • Nicola Shannon, RegN, BA VP, Clinical Operations • • Experienced senior executive in clinical operations Former Vice President of Clinical Operations at Kaleido Biosciences SCIENTIFIC ADVISORY BOARD Roy Freeman, MD Founder & Chairman of the SAB Expert in Automic & Peripheral Nerve Disorders • Professor of Neurology, Harvard Medical School • Staff Neurologist and Director of the Center for Autonomic and Peripheral Nerve Disorders at Beth Israel Deaconess Medical Center, Boston Robert H. Dworkin, PhD. Leader in Neuropathy Bob Rappaport, MD Regulatory Expert • Professor of Anesthesiology, Neurology, Psychiatry, and Experimental Therapeutics at the University of Rochester School of Medicine Director of the Anesthesiology Clinical Research Center • Former Division Director of Anesthesia, Analgesia and Addiction Products at the FDA President and owner of Analgesic Concepts LLC • • 22
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