Document and Entity Information
Document and Entity Information - shares | 3 Months Ended | |
Mar. 31, 2020 | May 11, 2020 | |
Cover [Abstract] | ||
Document Type | 10-Q | |
Amendment Flag | false | |
Document Period End Date | Mar. 31, 2020 | |
Document Fiscal Year Focus | 2020 | |
Document Fiscal Period Focus | Q1 | |
Trading Symbol | PTI | |
Entity Registrant Name | PROTEOSTASIS THERAPEUTICS, INC. | |
Entity Central Index Key | 0001445283 | |
Current Fiscal Year End Date | --12-31 | |
Entity Filer Category | Non-accelerated Filer | |
Entity Common Stock, Shares Outstanding | 52,147,656 | |
Entity Current Reporting Status | Yes | |
Entity Interactive Data Current | Yes | |
Entity Shell Company | false | |
Entity Small Business | true | |
Entity Emerging Growth Company | true | |
Entity Ex Transition Period | true | |
Entity Address, State or Province | MA | |
Entity File Number | 001-37695 | |
Entity Tax Identification Number | 20-8436652 | |
Entity Address, Address Line One | 80 Guest Street | |
Entity Address, Address Line Two | Suite 500 | |
Entity Address, City or Town | Boston | |
Entity Address, Postal Zip Code | 02135 | |
City Area Code | 617 | |
Local Phone Number | 225-0096 | |
Title of 12(b) Security | Common stock, par value $0.001 per share | |
Security Exchange Name | NASDAQ | |
Entity Incorporation, State or Country Code | DE | |
Document Quarterly Report | true | |
Document Transition Report | false |
Condensed Balance Sheets
Condensed Balance Sheets - USD ($) $ in Thousands | Mar. 31, 2020 | Dec. 31, 2019 |
Current assets: | ||
Cash and cash equivalents | $ 33,351 | $ 25,008 |
Short-term investments | 23,753 | 44,459 |
Prepaids and other current assets | 2,489 | 1,404 |
Total current assets | 59,593 | 70,871 |
Operating lease, right-of-use asset | 12,318 | 12,631 |
Property and equipment, net | 350 | 394 |
Restricted cash | 828 | 828 |
Total assets | 73,089 | 84,724 |
Current liabilities: | ||
Accounts payable | 1,201 | 2,283 |
Accrued expenses | 4,725 | 6,864 |
Operating lease liabilities | 1,179 | 1,153 |
Short-term borrowings | 1,099 | |
Total current liabilities | 8,204 | 10,300 |
Derivative liability | 3 | 3 |
Operating lease liabilities, net of current portion | 11,742 | 12,043 |
Total liabilities | 19,949 | 22,346 |
Commitments and contingencies | ||
Stockholders’ equity: | ||
Preferred stock, $0.001 par value; 5,000,000 shares authorized; no shares issued and outstanding as of March 31, 2020 and December 31, 2019 | ||
Common stock, $0.001 par value; 125,000,000 shares authorized; 52,147,656 and 52,116,629 shares issued and outstanding as of March 31, 2020 and December 31, 2019, respectively | 52 | 52 |
Additional paid-in capital | 399,583 | 398,979 |
Accumulated other comprehensive income | 43 | 7 |
Accumulated deficit | (346,538) | (336,660) |
Total stockholders’ equity | 53,140 | 62,378 |
Total liabilities and stockholders’ equity | $ 73,089 | $ 84,724 |
Condensed Balance Sheets (Paren
Condensed Balance Sheets (Parenthetical) - $ / shares | Mar. 31, 2020 | Dec. 31, 2019 |
Statement Of Financial Position [Abstract] | ||
Preferred stock, par value | $ 0.001 | $ 0.001 |
Preferred stock, shares authorized | 5,000,000 | 5,000,000 |
Preferred stock, shares issued | 0 | 0 |
Preferred stock, shares outstanding | 0 | 0 |
Common stock, par value | $ 0.001 | $ 0.001 |
Common stock, shares authorized | 125,000,000 | 125,000,000 |
Common stock, shares issued | 52,147,656 | 52,116,629 |
Common stock, shares outstanding | 52,147,656 | 52,116,629 |
Condensed Statements of Operati
Condensed Statements of Operations and Comprehensive Loss - USD ($) $ in Thousands | 3 Months Ended | |
Mar. 31, 2020 | Mar. 31, 2019 | |
Income Statement [Abstract] | ||
Revenue | $ 5,000 | |
Operating expenses: | ||
Research and development | $ 6,518 | 16,148 |
General and administrative | 3,587 | 3,943 |
Total operating expenses | 10,105 | 20,091 |
Loss from operations | (10,105) | (15,091) |
Interest income | 207 | 357 |
Interest expense | (3) | |
Other income, net | 23 | 316 |
Net loss | $ (9,878) | $ (14,418) |
Net loss per share—basic and diluted | $ (0.19) | $ (0.28) |
Weighted average common shares outstanding—basic and diluted | 52,146,633 | 50,976,907 |
Other comprehensive income: | ||
Unrealized gain on investments | $ 36 | $ 17 |
Comprehensive loss | $ (9,842) | $ (14,401) |
Condensed Statements of Stockho
Condensed Statements of Stockholders' Equity - USD ($) $ in Thousands | Total | Common Stock [Member] | Additional Paid-in Capital [Member] | Accumulated Other Comprehensive Income [Member] | Accumulated Deficit [Member] |
Beginning balance at Dec. 31, 2018 | $ 114,342 | $ 51 | $ 391,825 | $ 1 | $ (277,535) |
Beginning balance, shares at Dec. 31, 2018 | 50,808,422 | ||||
Exercise of stock options | 3 | 3 | |||
Exercise of stock options, shares | 2,543 | ||||
Stock-based compensation expense | 801 | 801 | |||
Issuance of common stock for payment of consulting services | 169 | 169 | |||
Issuance of common stock for payment of consulting services, shares | 46,153 | ||||
Issuance of common stock pursuant to employee stock purchase plan | 53 | 53 | |||
Issuance of common stock pursuant to employee stock purchase plan, shares | 22,615 | ||||
Vesting of restricted stock units, shares | 163,425 | ||||
Other comprehensive income | 17 | 17 | |||
Net loss | (14,418) | (14,418) | |||
Ending balance at Mar. 31, 2019 | 100,967 | $ 51 | 392,851 | 18 | (291,953) |
Ending balance, shares at Mar. 31, 2019 | 51,043,158 | ||||
Beginning balance at Dec. 31, 2019 | $ 62,378 | $ 52 | 398,979 | 7 | (336,660) |
Beginning balance, shares at Dec. 31, 2019 | 52,116,629 | 52,116,629 | |||
Stock-based compensation expense | $ 578 | 578 | |||
Issuance of common stock pursuant to employee stock purchase plan | 26 | 26 | |||
Issuance of common stock pursuant to employee stock purchase plan, shares | 31,027 | ||||
Other comprehensive income | 36 | 36 | |||
Net loss | (9,878) | (9,878) | |||
Ending balance at Mar. 31, 2020 | $ 53,140 | $ 52 | $ 399,583 | $ 43 | $ (346,538) |
Ending balance, shares at Mar. 31, 2020 | 52,147,656 | 52,147,656 |
Condensed Statements of Cash Fl
Condensed Statements of Cash Flows - USD ($) $ in Thousands | 3 Months Ended | |
Mar. 31, 2020 | Mar. 31, 2019 | |
Cash flows from operating activities: | ||
Net loss | $ (9,878) | $ (14,418) |
Adjustments to reconcile net loss to cash used in operating activities: | ||
Depreciation and amortization | 357 | 351 |
Accretion of short-term investments | (26) | (317) |
Stock-based compensation expense | 578 | 801 |
Stock issued for consulting services | 169 | |
Changes in operating assets and liabilities: | ||
Prepaids and other current assets | (1,085) | (653) |
Other assets | (88) | |
Accounts payable | (1,082) | 120 |
Accrued expenses | (2,139) | 858 |
Operating lease liabilities | (275) | (252) |
Net cash used in operating activities | (13,550) | (13,429) |
Cash flows from investing activities: | ||
Purchases of short-term investments | (5,232) | (20,844) |
Proceeds received from maturities of short-term investments | 26,000 | 37,000 |
Purchases of property and equipment | (9) | |
Net cash provided by investing activities | 20,768 | 16,147 |
Cash flows from financing activities: | ||
Proceeds from exercise of stock options | 3 | |
Proceeds from issuance of common stock pursuant to employee stock purchase plan | 26 | 53 |
Proceeds from issuance of short-term borrowings | 1,220 | |
Repayment of short-term borrowings | (121) | |
Net cash provided by financing activities | 1,125 | 56 |
Net increase in cash, cash equivalents and restricted cash | 8,343 | 2,774 |
Cash, cash equivalents and restricted cash at beginning of period | 25,836 | 29,638 |
Cash, cash equivalents and restricted cash at end of period | $ 34,179 | $ 32,412 |
Nature of the Business
Nature of the Business | 3 Months Ended |
Mar. 31, 2020 | |
Organization Consolidation And Presentation Of Financial Statements [Abstract] | |
Nature of the Business | 1. Nature of the Business Proteostasis Therapeutics, Inc. (the “Company”) was incorporated in Delaware on December 13, 2006. The Company is a clinical stage biopharmaceutical company committed to the discovery and development of novel therapeutics to treat cystic fibrosis (“CF”) through theratyping, or the process of matching modulators to individual response to treatment regardless of CFTR mutations. CF is a disease caused by defects in the function or abundance of cystic fibrosis transmembrane conductance regulator (“CFTR”) protein. Although, CF is defined as a monogenic recessive genetic disorder caused by mutations in the CFTR gene, there is a broad range of disease activity for different organ systems in CF, including lung disease, meconium ileus, diabetes, and liver disease, even for CF patients who are homozygous for the most common mutation, F508del mutation. In summary, CF genotype does not always match CF phenotype. Since its inception, the Company has devoted substantially all of its efforts to organizing and staffing the Company, business planning, raising capital, acquiring and developing product and technology rights, and conducting research and development activities. It has funded its operations to date with proceeds from the sale of preferred stock, the issuance of convertible promissory notes, proceeds from its initial public offering in February 2016, proceeds from its follow-on public offerings, and payments received in connection with collaboration agreements and a research grant, as well as funds from the sale of stock under the at-the-market offering program described below. The Company does not have any products approved for sale and has not generated any revenue from product sales. The Company has not generated any revenue since inception. As a result, the Company has incurred recurring losses and requires significant cash resources to execute its business plans. In accordance with ASC 205-40, Going Concern . As of March 31, 2020, the Company had an accumulated deficit of $346.5 million. The Company has incurred losses and negative cash flows from operations since its inception. During the three months ended March 31, 2020, the Company incurred losses of $9.9 million and used $13.6 million of cash in operations. $57.1 million will be sufficient to fund its operating expenses and capital requirements, based upon its current operating plan, for at least 12 months from the date that these financial statements are issued. novel coronavirus (“COVID-19”) At-the-Market Offering Program In May 2019, the Company entered into a sales agreement with H.C. Wainwright & Co., LLC (“HCW”) with respect to an at-the-market (“ATM”) offering program under which the Company may issue and sell, from time-to-time at its sole discretion, shares of its common stock, in an aggregate offering amount of up to $56.6 million (the “HCW ATM program”). HCW acts as the Company’s sales agent and will use commercially reasonable efforts to sell shares of common stock from time-to-time, based upon instruction from the Company. Common stock will be sold at prevailing market prices at the time of the sale, and as a result, prices may vary. The Company will pay HCW up to 3% of the gross proceeds from any common stock sold through the sales agreement. As of December 31, 2019, the Company sold 987,653 shares of its common stock for total net proceeds of approximately $3.5 million under the HCW ATM program. The Company did not sell any shares of its common stock under the ATM program during the three months ended March 31, 2020. In March 2018, the Company entered into a sales agreement with Leerink Partners LLC (“Leerink”) with respect to an ATM offering program under which the Company could have issued and sold, from time to time at its sole discretion, shares of its common stock, in an aggregate offering amount of up to $50.0 million. As of March 31, 2019, the Company had sold an aggregate of 3,475,166 shares of its common stock for total net proceeds of approximately $21.6 million under the ATM program. Effective April 7, 2019, the Company terminated this ATM offering program. |
Summary of Significant Accounti
Summary of Significant Accounting Policies | 3 Months Ended |
Mar. 31, 2020 | |
Accounting Policies [Abstract] | |
Summary of Significant Accounting Policies | 2. Summary of Significant Accounting Policies Unaudited Interim Financial Information The condensed balance sheet as of December 31, 2019 was derived from audited financial statements but does not include all disclosures required by accounting principles generally accepted in the United States of America (“GAAP”). The accompanying condensed financial statements, as of March 31, 2020 and for the three months ended March 31, 2020, are unaudited and have been prepared by the Company pursuant to the rules and regulations of the Securities and Exchange Commission (the “SEC”) for interim financial statements. Certain information and footnote disclosures normally included in financial statements prepared in accordance with GAAP have been condensed or omitted pursuant to such rules and regulations. The Company believes that the disclosures are adequate to make the information presented not misleading. These unaudited condensed financial statements should be read in conjunction with the Company’s audited financial statements and the notes thereto for the year ended December 31, 2019 included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2019 filed with the SEC on March 10, 2020. In the opinion of management, all adjustments, consisting only of normal recurring adjustments, as necessary for the fair statement of the Company’s financial position as of March 31, 2020, results of its operations for the three months ended March 31, 2020, and cash flows for the three months ended March 31, 2020, have been made. The results of operations for the three months ended March 31, 2020 are not necessarily indicative of the results of operations to be expected for the year ending December 31, 2020. Summary of Significant Accounting Policies The Company’s significant accounting policies, which are disclosed in the audited consolidated financial statements for the year ended December 31, 2019 and the notes thereto, are included in the Company’s Annual Report on Form 10-K that was filed with the SEC on March 10, 2020. There were no changes to significant accounting policies during the three months ended March 31, 2020, except for the items noted below. Risks and Uncertainties The Company is monitoring the potential impact of COVID-19, if any, on the carrying value of certain assets. To date, the Company has not experienced material business disruption, nor has it incurred impairment of any assets as a result of COVID-19. The extent to which these events may impact the Company’s business, clinical development and regulatory efforts, and the value of its common stock, will depend on future developments, which are highly uncertain and cannot be predicted at this time. The duration and intensity of these impacts and resulting disruption to the Company’s operations is uncertain and the Company will continue to assess the financial impact In addition, the Company is subject to other challenges and risks specific to its business and its ability to execute on its business plan and strategy, as well as risks and uncertainties common to companies in the biopharmaceutical industry with development and commercial operations, including, without limitation, risks and uncertainties associated with: obtaining regulatory approval of its late-stage product candidates; delays or problems in obtaining clinical supply, loss of single source suppliers or failure to comply with manufacturing regulations; identifying, acquiring or in-licensing additional products or product candidates; biopharmaceutical product development and the inherent uncertainty of clinical success; and the challenges of complying with applicable regulatory requirements. In addition, to the extent the ongoing COVID-19 pandemic adversely affects our business and results of operations, it may also have the effect of heightening many of the other risks and uncertainties discussed above. Use of Estimates The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities at the date of the financial statements, and the reported amounts of revenue and expenses during the reporting periods. Significant estimates and assumptions reflected in these financial statements include, but are not limited to, revenue recognition, the accrual for research and development expenses, and the valuation of common stock and the derivative liability. Estimates are periodically reviewed in light of changes in circumstances, facts, and experience. Changes in estimates are recorded in the period in which they become known. Actual results could differ from those estimates. Recently Issued and Adopted Accounting Pronouncements ASU No. 2018-13, Fair Value Measurement (Topic 820): Changes to the Disclosure Requirements for Fair Value Measurement In August 2018, the FASB issued ASU No. 2018-13, Disclosure Framework – Changes to the Disclosure Requirements for Fair Value Measurement Recently Issued Accounting Pronouncements ASU No. 2016-13, Financial Instruments – Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments In June 2016, the FASB issued ASU No. 2016-13, Financial Instruments - Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments |
Short-Term Investments
Short-Term Investments | 3 Months Ended |
Mar. 31, 2020 | |
Cash Cash Equivalents And Short Term Investments [Abstract] | |
Short-Term Investments | 3. Short-Term Investments The following table summarizes the Company’s short-term investments as of March 31, 2020 and December 31, 2019 (in thousands): March 31, 2020 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value U.S government-sponsored enterprise securities $ 16,455 $ 29 $ — $ 16,484 U.S. treasury securities 7,255 14 — 7,269 $ 23,710 $ 43 $ — $ 23,753 December 31, 2019 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value U.S government-sponsored enterprise securities $ 20,456 $ 2 $ (1 ) $ 20,457 U.S. treasury securities 23,996 7 (1 ) 24,002 $ 44,452 $ 9 $ (2 ) $ 44,459 Short-term investments represent holdings of available-for-sale debt securities and are reported at fair value with unrealized gains and losses reported net of taxes, if material, in other comprehensive income. The Company did not have any realized gains or losses on its short-term investments for the three months ended March 31, 2020 and 2019 2019 |
Fair Value of Financial Assets
Fair Value of Financial Assets and Liabilities | 3 Months Ended |
Mar. 31, 2020 | |
Fair Value Disclosures [Abstract] | |
Fair Value of Financial Assets and Liabilities | 4. Fair Value of Financial Assets and Liabilities The following tables present information about the Company’s financial assets and liabilities measured at fair value on a recurring basis and indicate the level of the fair value hierarchy utilized to determine such fair values (in thousands): Fair Value Measurements as of March 31, 2020 using: Level 1 Level 2 Level 3 Total Assets: Cash equivalents: Money market funds $ 32,873 $ — $ — $ 32,873 Short-term investments: U.S. government-sponsored enterprise securities — 16,484 — 16,484 U.S. treasury securities — 7,269 — 7,269 $ 32,873 $ 23,753 $ — $ 56,626 Liabilities: Derivative liability $ — $ — $ 3 $ 3 Fair Value Measurements as of December 31, 2019 using: Level 1 Level 2 Level 3 Total Assets: Cash equivalents: Money market funds $ 23,906 $ — $ — $ 23,906 Short-term investments: U.S. government-sponsored enterprise securities — 20,457 — 20,457 U.S. treasury securities — 24,002 — 24,002 $ 23,906 $ 44,459 $ — $ 68,365 Liabilities: Derivative liability $ — $ — $ 3 $ 3 During the periods ended March 31, 2020 and December 31, 2019, there were no transfers between Level 1, Level 2 and Level 3. The derivative liability relates to a cash settlement option associated with the change of control provision in the Company’s Cystic Fibrosis Foundation, Inc. (“CFF”) agreement, which meets the definition of a derivative. The fair value of the derivative liability is based on significant inputs not observable in the market, which represents a Level 3 measurement within the fair value hierarchy. The fair value of the derivative instrument was determined using the Monte-Carlo simulation analysis. In determining the fair value of the derivative liability, the inputs impacting fair value include the fair value of the Company’s common stock, expected term of the derivative instrument, expected volatility of the common stock price, risk-free interest rate, expected sales-based milestone payments, discount rate, probability of a change of control event, and the probability that the counterparty would elect to accept the alternative cash payment in lieu of its right to the future sales-based milestone payments. The fair value of the derivative liability was not material at March 31, 2020 and December 31, 2019. |
Prepaids and Other Current Asse
Prepaids and Other Current Assets | 3 Months Ended |
Mar. 31, 2020 | |
Prepaid Expense And Other Assets Current [Abstract] | |
Prepaids and Other Current Assets | 5. Prepaids and Other Current Assets Prepaids and other current assets consisted of the following (in thousands): March 31, December 31, 2020 2019 Prepaid clinical, manufacturing and scientific expenses $ 429 $ 767 Prepaid insurance expenses 1,629 125 Other prepaid expenses and other current assets 431 512 $ 2,489 $ 1,404 |
Accrued Expenses
Accrued Expenses | 3 Months Ended |
Mar. 31, 2020 | |
Payables And Accruals [Abstract] | |
Accrued Expenses | 6. Accrued Expenses Accrued expenses consisted of the following (in thousands): March 31, December 31, 2020 2019 Accrued research and development expenses $ 3,127 $ 3,186 Accrued payroll and related expenses 1,118 3,203 Accrued professional fees 429 397 Accrued other 51 78 $ 4,725 $ 6,864 |
Short-Term Borrowings
Short-Term Borrowings | 3 Months Ended |
Mar. 31, 2020 | |
Short Term Borrowings [Abstract] | |
Short-Term Borrowings | 7. Short-Term Borrowings As of March 31, 2020, the Company had short-term borrowings of $1.1 million consisting of a Commercial Insurance Premium Finance and Security Agreement (the “Finance and Security Agreement”) entered into on February 27, 2020. The Finance and Security Agreement has a ten-month repayment period with an annual interest rate of 2.59% and a maturity of December 11, 2020. Collateral under the Finance and Security Agreement includes the right, title and interest in certain business insurance policies. As of March 31, 2020, the Company has paid less than $0.1 million in interest on short-term borrowings. |
Stock-Based Compensation
Stock-Based Compensation | 3 Months Ended |
Mar. 31, 2020 | |
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract] | |
Stock-Based Compensation | 8 . Stock-Based Compensation 2016 Stock Option and Incentive Plan On February 3, 2016, the Company’s stockholders approved the 2016 Stock Option and Incentive Plan (the “2016 Plan”), which became effective on February 9, 2016. The 2016 Plan provides for the grant of incentive stock options, nonqualified stock options, stock appreciation rights, restricted stock units, restricted stock awards and other stock-based awards. The number of shares initially reserved for issuance under the 2016 Plan was 1,581,839 shares. The number of shares of common stock that may be issued under the 2016 Plan will automatically increase each January 1, beginning January 1, 2017, by the lesser of 3% of the shares of the Company’s common stock outstanding on the immediately preceding December 31, or an amount determined by the Company’s board of directors or the compensation committee of the board of directors. The shares of common stock underlying any awards that are forfeited, canceled, repurchased or are otherwise terminated by the Company under the 2016 Plan and the 2008 Equity Incentive Plan, as amended (the “2008 Plan”) will be added back to the shares of common stock available for issuance under the 2016 Plan. On January 1, 2020, an additional 1,563,498 shares were reserved for issuance under the 2016 Plan. As of March 31, 2020, the total number of shares of the Company’s common stock reserved for issuance under the 2016 Plan was 9,972,038 and the Company had 4,441,627 shares available for future issuance under the 2016 Plan. 2016 Employee Stock Purchase Plan On February 3, 2016, the Company’s stockholders approved the 2016 Employee Stock Purchase Plan (the “2016 ESPP”), which became effective in connection with the completion of the Company’s initial public offering. A total of 138,757 shares of common stock were initially reserved for issuance under the 2016 ESPP. In addition, the number of shares of common stock that may be issued under the 2016 ESPP will automatically increase each January 1, beginning January 1, 2017, by the lesser of (i) 138,757 shares of common stock, (ii) 1% of the Company’s shares of common stock outstanding on the immediately preceding December 31, or (iii) an amount determined by the Company’s board of directors or the compensation committee of the board of directors. During the three months ended March 31, 2020, 31,027 shares of common stock were issued pursuant to the 2016 ESPP. As of March 31, 2020, the total number of shares reserved under the 2016 ESPP was 580,742 shares. The Company recognized less than $0.1 million of stock-based compensation during the three months ended March 31, 2020 related to the 2016 ESPP. Restricted Stock Units (RSUs) On February 4, 2020, the Company’s board approved payment to be made to a nonemployee through a grant of RSUs based on the February 4, 2020 closing share price of the Company’s common stock. The grant did not meet the criteria for liability classification as there was a fixed number of shares to be issued and there is no variability in the number of shares which had been granted. The requisite service period for the awards is from February 4, 2020 to August 4, 2020 (the vesting period). The Company recognized employee stock-based compensation expense for the RSU grant on a straight-line basis over the vesting period of the awards. As of March 31, 2020, 4,519 RSUs were granted and the Company recognized less than $0.1 million of stock-based compensation expense during the three months ended March 31, 2020. The following table summarizes the Company’s RSU activity for the three months ended March 31, 2020: Number of Shares Weighted Average Grant Date Fair Value Unvested balance at December 31, 2019 — $ — Granted 4,519 1.77 Vested — — Forfeited — — Unvested balance at March 31, 2020 4,519 $ — Stock-Based Compensation Stock-based compensation expense, including shares issued to a nonemployee for consulting services, was classified in the statements of operations as follows (in thousands): Three Months Ended March 31, 2020 2019 Research and development $ 230 $ 370 General and administrative 348 600 $ 578 $ 970 The following table summarizes the Company’s stock option activity for the three months ended March 31, 2020 (in thousands except share and per share amounts): Number of Shares Weighted Average Exercise Price Per Share Weighted Average Remaining Contractual Term Aggregate Intrinsic Value (Years) Outstanding at December 31, 2019 4,364,839 $ 5.30 7.32 $ 132 Granted 1,528,600 1.57 Forfeited (363,028 ) 6.34 Outstanding at March 31, 2020 5,530,411 $ 4.20 7.85 $ 14 Exercisable at March 31, 2020 2,509,969 $ 5.79 6.48 $ 5 Vested and expected to vest at March 31, 2020 5,447,161 $ 4.23 7.96 $ 14 The grant date fair value of options granted during the period was $1.7 million, or $1.10 per share on a weighted-average basis, and will be recognized as compensation expense over the requisite service period of four years. As of March 31, 2020, there was $5.5 million of unrecognized compensation cost related to employee and nonemployee unvested stock options granted under the 2016 Plan, which is expected to be recognized over a weighted-average remaining service period of 2.55 years. Stock compensation costs have not been capitalized by the Company. Prior to 2013, the Company issued options to purchase 203,964 shares of common stock to nonemployees, primarily members of the Company’s scientific advisory board, that vest upon the achievement of specified development and clinical milestones. As of March 31, 2020, options for the purchase of 83,250 shares held by nonemployees remained unvested, pending achievement of the specified milestones. |
Significant Agreements
Significant Agreements | 3 Months Ended |
Mar. 31, 2020 | |
Organization Consolidation And Presentation Of Financial Statements [Abstract] | |
Significant Agreements | 9 . Significant Agreements Genentech In December 2018, the Company entered into a Technology Transfer and License Agreement (the “Genentech Agreement”) with Genentech, Inc. (“Genentech”) under which the Company granted Genentech an exclusive worldwide license for technology and materials relating to potential therapeutic small molecule modulators of an undisclosed target within the proteostasis network. The rights do not include CFTR modulators and are unrelated to the Company’s investigational medicines or other ongoing research programs in cystic fibrosis. In connection with the terms of the Genentech Agreement, the Company is entitled to a nonrefundable cash payment of $5.0 million following the successful completion of the technology and materials transfer to Genentech and future milestone payments in the aggregate of approximately $96.0 million upon the achievement of specified development, regulatory, and commercial milestones. In addition, Genentech is obligated to pay the Company tiered royalties in the low single-digits based on net sales of products covered by the licenses granted under the Genentech Agreement. There are no cancellation, termination, or refund provisions in the Genentech Agreement that contain material financial consequences to the Company. Unless earlier terminated, the Genentech Agreement continues in full force and effect until the passing or expiration of all royalty payment obligations. Reciprocal termination rights under the agreement include termination for breach and termination for bankruptcy. Genentech may terminate the Genentech Agreement in its entirety, for convenience, upon thirty days’ notice to the Company. The Company evaluated the Genentech Agreement in accordance with the provisions of Accounting Standards Codification Topic 606, Revenue from Contracts with Customers As of March 31, 2020, the Company has measured the transaction price solely in reference to the $5.0 million payment due upon receipt of notice from Genentech regarding the satisfactory completion of the technology and materials transfer. None of the variable consideration payable under the arrangement has been included in the transaction price as of March 31, 2020. Through March 31, 2020, the Company has not achieved any research, development, regulatory, or commercial milestones, or earned any royalties under the Genentech Agreement. The Company utilizes “the most likely” amount method to estimate the amount of research, development, and regulatory milestone payments to be received. As part of the evaluation for the research and development milestone payments, the Company considers several factors including the stage of research and development of the compounds included in the arrangement, the risk associated with the remaining research and development work required to achieve the milestone, and the Company’s level of involvement in the research and development activities. Regulatory milestone payments are triggered upon the first commercial sale following receipt of regulatory approval from the FDA or other global regulatory authorities; therefore, such amounts will be excluded from the transaction price until the associated regulatory approval is received. The commercial milestone payments and royalties are subject to the royalty recognition constraint whereby such amounts will be recognized as revenue upon the later of: (i) when the related sales occur, or (ii) when the performance obligation to which some or all of the payment has been allocated has been satisfied, or partially satisfied, because the exclusive license is deemed to be the sole or predominant item to which the payments relate. As all performance obligations are satisfied, the Company will recognize royalty revenue at the date the sales occur. The Company did not adjust the promised amount of consideration for the effects of a significant financing component because the Company expects that the period between when the promised goods and services are transferred and when the customer pays for those goods and services will be one year or less. There were no changes in the transaction price for the three months ended March 31, 2020. The transaction price of $5.0 million allocated to the combined performance obligation was recognized as revenue in February 2019 at the point in time that Genentech provided notice regarding the satisfactory completion of the technology and materials transfer. Upon that successful execution of the technology and materials transfer, control was deemed to be transferred for both the exclusive license and the technology and materials transfer promises, therefore the risks and rewards of ownership had been conveyed. As of March 31, 2020, the Company did not have any receivables or deferred revenue related to the Genentech Agreement because no payments under the arrangement became due, nor had the underlying performance obligation been satisfied. |
Income Taxes
Income Taxes | 3 Months Ended |
Mar. 31, 2020 | |
Income Tax Disclosure [Abstract] | |
Income Taxes | 10 . Income Taxes The Company did not record a federal or state income tax benefit for its losses for the three months ended March 31, 2020 and 2019, respectively, due to the conclusion that a full valuation allowance is required against the Company’s deferred tax assets. All the Company’s losses before income taxes were generated in the United States. |
Net Loss per Share
Net Loss per Share | 3 Months Ended |
Mar. 31, 2020 | |
Earnings Per Share [Abstract] | |
Net Loss per Share | 1 1 . Net Loss per Share Basic and diluted net loss per share was calculated as follows (in thousands, except share and per share amounts): Three Months Ended March 31, 2020 2019 Numerator: Net loss $ (9,878 ) $ (14,418 ) Denominator: Weighted average number of common shares outstanding—basic and diluted 52,146,633 50,976,907 Net loss per share—basic and diluted $ (0.19 ) $ (0.28 ) The following common stock equivalents have been excluded from the computation of diluted weighted-average shares outstanding, because such securities had an antidilutive impact : March 31, 2020 2019 Options to purchase common stock 5,530,411 4,564,427 Restricted stock units 4,519 — 5,534,930 4,564,427 |
Leases
Leases | 3 Months Ended |
Mar. 31, 2020 | |
Leases [Abstract] | |
Leases | 12. Leases The Company has an operating lease for office and laboratory space for its corporate headquarters in Boston, Massachusetts. The lease commenced in January 2018 and rent payments began in April 2018. This lease has a ten-year initial term with an option to extend for seven additional years. The Company has the right to terminate the lease in the event of the inability to use the space due to substantial damage while the lessor has the right to terminate the lease if the Company defaults on the lease financial obligations. Per the terms of the lease agreement, the Company does not have any residual value guarantees. In calculating the present value of the lease payments, the Company utilized its incremental borrowing rate based on electing the original lease term to account for each lease component and its associated non-lease components as a single lease component. It has allocated all the contract consideration across lease components only. This may result in the initial and subsequent measurement of the balances of the right-of-use asset and lease liability for leases being greater than if the policy election was not applied. The Company’s real estate lease in Boston is considered a net lease, as the non-lease components (i.e., common area maintenance) are paid separately from rent, based on actual costs incurred. Therefore, the non-lease components were not included in the right-of-use asset and liability and are reflected as an expense in the period incurred. As of March 31, 2020, and December 31, 2019, assets under operating lease were $12.3 million and $12.6 million, respectively. The elements of lease expense were as follows (in thousands): For the Three Months Ended March 31, 2020 2019 Lease cost Operating lease cost $ 462 $ 462 Variable lease cost (1) 103 137 Total lease cost $ 565 $ 599 Other information Operating cash flows used for operating leases $ 425 $ 414 Operating lease liabilities arising from obtaining right-of-use assets $ 12,921 $ 14,000 Weighted-average remaining lease term 8 years 9 years Weighted-average discount rate 4.50 % 4.50 % (1) The variable lease costs for the three months ended March 31, 2020 and 2019 Future lease payments under no ncancelable leases as of March 31, 2020 (in thousands): Future Operating Lease Payments 2020 $ 1,308 2021 1,780 2022 1,829 2023 1,880 2024 1,931 Thereafter 6,825 Total lease payments 15,553 Less: imputed interest (2,632 ) Total operating lease liabilities $ 12,921 |
Summary of Significant Accoun_2
Summary of Significant Accounting Policies (Policies) | 3 Months Ended |
Mar. 31, 2020 | |
Accounting Policies [Abstract] | |
Unaudited Interim Financial Information | Unaudited Interim Financial Information The condensed balance sheet as of December 31, 2019 was derived from audited financial statements but does not include all disclosures required by accounting principles generally accepted in the United States of America (“GAAP”). The accompanying condensed financial statements, as of March 31, 2020 and for the three months ended March 31, 2020, are unaudited and have been prepared by the Company pursuant to the rules and regulations of the Securities and Exchange Commission (the “SEC”) for interim financial statements. Certain information and footnote disclosures normally included in financial statements prepared in accordance with GAAP have been condensed or omitted pursuant to such rules and regulations. The Company believes that the disclosures are adequate to make the information presented not misleading. These unaudited condensed financial statements should be read in conjunction with the Company’s audited financial statements and the notes thereto for the year ended December 31, 2019 included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2019 filed with the SEC on March 10, 2020. In the opinion of management, all adjustments, consisting only of normal recurring adjustments, as necessary for the fair statement of the Company’s financial position as of March 31, 2020, results of its operations for the three months ended March 31, 2020, and cash flows for the three months ended March 31, 2020, have been made. The results of operations for the three months ended March 31, 2020 are not necessarily indicative of the results of operations to be expected for the year ending December 31, 2020. |
Summary of Significant Accounting Policies | Summary of Significant Accounting Policies The Company’s significant accounting policies, which are disclosed in the audited consolidated financial statements for the year ended December 31, 2019 and the notes thereto, are included in the Company’s Annual Report on Form 10-K that was filed with the SEC on March 10, 2020. There were no changes to significant accounting policies during the three months ended March 31, 2020, except for the items noted below. |
Risks and Uncertainties | Risks and Uncertainties The Company is monitoring the potential impact of COVID-19, if any, on the carrying value of certain assets. To date, the Company has not experienced material business disruption, nor has it incurred impairment of any assets as a result of COVID-19. The extent to which these events may impact the Company’s business, clinical development and regulatory efforts, and the value of its common stock, will depend on future developments, which are highly uncertain and cannot be predicted at this time. The duration and intensity of these impacts and resulting disruption to the Company’s operations is uncertain and the Company will continue to assess the financial impact In addition, the Company is subject to other challenges and risks specific to its business and its ability to execute on its business plan and strategy, as well as risks and uncertainties common to companies in the biopharmaceutical industry with development and commercial operations, including, without limitation, risks and uncertainties associated with: obtaining regulatory approval of its late-stage product candidates; delays or problems in obtaining clinical supply, loss of single source suppliers or failure to comply with manufacturing regulations; identifying, acquiring or in-licensing additional products or product candidates; biopharmaceutical product development and the inherent uncertainty of clinical success; and the challenges of complying with applicable regulatory requirements. In addition, to the extent the ongoing COVID-19 pandemic adversely affects our business and results of operations, it may also have the effect of heightening many of the other risks and uncertainties discussed above. |
Use of Estimates | Use of Estimates The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities at the date of the financial statements, and the reported amounts of revenue and expenses during the reporting periods. Significant estimates and assumptions reflected in these financial statements include, but are not limited to, revenue recognition, the accrual for research and development expenses, and the valuation of common stock and the derivative liability. Estimates are periodically reviewed in light of changes in circumstances, facts, and experience. Changes in estimates are recorded in the period in which they become known. Actual results could differ from those estimates. |
Recently Issued and Adopted Accounting Pronouncements | Recently Issued and Adopted Accounting Pronouncements ASU No. 2018-13, Fair Value Measurement (Topic 820): Changes to the Disclosure Requirements for Fair Value Measurement In August 2018, the FASB issued ASU No. 2018-13, Disclosure Framework – Changes to the Disclosure Requirements for Fair Value Measurement Recently Issued Accounting Pronouncements ASU No. 2016-13, Financial Instruments – Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments In June 2016, the FASB issued ASU No. 2016-13, Financial Instruments - Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments |
Short-Term Investments (Tables)
Short-Term Investments (Tables) | 3 Months Ended |
Mar. 31, 2020 | |
Cash Cash Equivalents And Short Term Investments [Abstract] | |
Summary of Short-Term Investments | The following table summarizes the Company’s short-term investments as of March 31, 2020 and December 31, 2019 (in thousands): March 31, 2020 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value U.S government-sponsored enterprise securities $ 16,455 $ 29 $ — $ 16,484 U.S. treasury securities 7,255 14 — 7,269 $ 23,710 $ 43 $ — $ 23,753 December 31, 2019 Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Fair Value U.S government-sponsored enterprise securities $ 20,456 $ 2 $ (1 ) $ 20,457 U.S. treasury securities 23,996 7 (1 ) 24,002 $ 44,452 $ 9 $ (2 ) $ 44,459 |
Fair Value of Financial Asset_2
Fair Value of Financial Assets and Liabilities (Tables) | 3 Months Ended |
Mar. 31, 2020 | |
Fair Value Disclosures [Abstract] | |
Schedule of Assets and Liabilities Measured at Fair Value on Recurring Basis | The following tables present information about the Company’s financial assets and liabilities measured at fair value on a recurring basis and indicate the level of the fair value hierarchy utilized to determine such fair values (in thousands): Fair Value Measurements as of March 31, 2020 using: Level 1 Level 2 Level 3 Total Assets: Cash equivalents: Money market funds $ 32,873 $ — $ — $ 32,873 Short-term investments: U.S. government-sponsored enterprise securities — 16,484 — 16,484 U.S. treasury securities — 7,269 — 7,269 $ 32,873 $ 23,753 $ — $ 56,626 Liabilities: Derivative liability $ — $ — $ 3 $ 3 Fair Value Measurements as of December 31, 2019 using: Level 1 Level 2 Level 3 Total Assets: Cash equivalents: Money market funds $ 23,906 $ — $ — $ 23,906 Short-term investments: U.S. government-sponsored enterprise securities — 20,457 — 20,457 U.S. treasury securities — 24,002 — 24,002 $ 23,906 $ 44,459 $ — $ 68,365 Liabilities: Derivative liability $ — $ — $ 3 $ 3 |
Prepaids and Other Current As_2
Prepaids and Other Current Assets (Tables) | 3 Months Ended |
Mar. 31, 2020 | |
Prepaid Expense And Other Assets Current [Abstract] | |
Schedule of Prepaids and Other Current Assets | Prepaids and other current assets consisted of the following (in thousands): March 31, December 31, 2020 2019 Prepaid clinical, manufacturing and scientific expenses $ 429 $ 767 Prepaid insurance expenses 1,629 125 Other prepaid expenses and other current assets 431 512 $ 2,489 $ 1,404 |
Accrued Expenses (Tables)
Accrued Expenses (Tables) | 3 Months Ended |
Mar. 31, 2020 | |
Payables And Accruals [Abstract] | |
Schedule of Accrued Expenses | Accrued expenses consisted of the following (in thousands): March 31, December 31, 2020 2019 Accrued research and development expenses $ 3,127 $ 3,186 Accrued payroll and related expenses 1,118 3,203 Accrued professional fees 429 397 Accrued other 51 78 $ 4,725 $ 6,864 |
Stock-Based Compensation (Table
Stock-Based Compensation (Tables) | 3 Months Ended |
Mar. 31, 2020 | |
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract] | |
Summary of Restricted Stock Unit Activity | The following table summarizes the Company’s RSU activity for the three months ended March 31, 2020: Number of Shares Weighted Average Grant Date Fair Value Unvested balance at December 31, 2019 — $ — Granted 4,519 1.77 Vested — — Forfeited — — Unvested balance at March 31, 2020 4,519 $ — |
Summary of Stock-Based Compensation Expense, Including Shares Issued to Nonemployee for Consulting Services | Stock-based compensation expense, including shares issued to a nonemployee for consulting services, was classified in the statements of operations as follows (in thousands): Three Months Ended March 31, 2020 2019 Research and development $ 230 $ 370 General and administrative 348 600 $ 578 $ 970 |
Summary of Stock Option Activity | The following table summarizes the Company’s stock option activity for the three months ended March 31, 2020 (in thousands except share and per share amounts): Number of Shares Weighted Average Exercise Price Per Share Weighted Average Remaining Contractual Term Aggregate Intrinsic Value (Years) Outstanding at December 31, 2019 4,364,839 $ 5.30 7.32 $ 132 Granted 1,528,600 1.57 Forfeited (363,028 ) 6.34 Outstanding at March 31, 2020 5,530,411 $ 4.20 7.85 $ 14 Exercisable at March 31, 2020 2,509,969 $ 5.79 6.48 $ 5 Vested and expected to vest at March 31, 2020 5,447,161 $ 4.23 7.96 $ 14 |
Net Loss per Share (Tables)
Net Loss per Share (Tables) | 3 Months Ended |
Mar. 31, 2020 | |
Earnings Per Share [Abstract] | |
Schedule of Basic and Diluted Net Loss per Share | Basic and diluted net loss per share was calculated as follows (in thousands, except share and per share amounts): Three Months Ended March 31, 2020 2019 Numerator: Net loss $ (9,878 ) $ (14,418 ) Denominator: Weighted average number of common shares outstanding—basic and diluted 52,146,633 50,976,907 Net loss per share—basic and diluted $ (0.19 ) $ (0.28 ) |
Schedule of Antidilutive Securities Excluded from Computation of Diluted Weighted-average Shares Outstanding | The following common stock equivalents have been excluded from the computation of diluted weighted-average shares outstanding, because such securities had an antidilutive impact : March 31, 2020 2019 Options to purchase common stock 5,530,411 4,564,427 Restricted stock units 4,519 — 5,534,930 4,564,427 |
Leases (Tables)
Leases (Tables) | 3 Months Ended |
Mar. 31, 2020 | |
Lessee Disclosure [Abstract] | |
Elements of Lease Expense | The elements of lease expense were as follows (in thousands): For the Three Months Ended March 31, 2020 2019 Lease cost Operating lease cost $ 462 $ 462 Variable lease cost (1) 103 137 Total lease cost $ 565 $ 599 Other information Operating cash flows used for operating leases $ 425 $ 414 Operating lease liabilities arising from obtaining right-of-use assets $ 12,921 $ 14,000 Weighted-average remaining lease term 8 years 9 years Weighted-average discount rate 4.50 % 4.50 % (1) The variable lease costs for the three months ended March 31, 2020 and 2019 |
Schedule of Future Lease Payments under Noncancelable Leases | Future lease payments under no ncancelable leases as of March 31, 2020 (in thousands): Future Operating Lease Payments 2020 $ 1,308 2021 1,780 2022 1,829 2023 1,880 2024 1,931 Thereafter 6,825 Total lease payments 15,553 Less: imputed interest (2,632 ) Total operating lease liabilities $ 12,921 |
Nature of the Business - Additi
Nature of the Business - Additional Information (Detail) - USD ($) | Mar. 31, 2019 | May 31, 2019 | Mar. 31, 2018 | Mar. 31, 2020 | Mar. 31, 2019 | Dec. 31, 2019 |
Nature of Business [Line Items] | ||||||
Accumulated deficit | $ (346,538,000) | $ (336,660,000) | ||||
Cash, cash equivalents and short-term investments | 57,100,000 | |||||
Net loss | (9,878,000) | $ (14,418,000) | ||||
Cash in operations | $ 13,550,000 | $ 13,429,000 | ||||
ATM Program [Member] | H.C. Wainwright & Co., LLC [Member] | ||||||
Nature of Business [Line Items] | ||||||
Common stock aggregate offering price | $ 56,600,000 | |||||
Percentage of gross proceeds from common stock sold through sales agreement | 3.00% | |||||
Number of shares issued and sold | 0 | 987,653 | ||||
Net proceeds from sales of common stock | $ 3,500,000 | |||||
ATM Program [Member] | Leerink Partners LLC [Member] | ||||||
Nature of Business [Line Items] | ||||||
Common stock aggregate offering price | $ 50,000,000 | |||||
Number of shares issued and sold | 3,475,166 | |||||
Net proceeds from sales of common stock | $ 21,600,000 |
Short-Term Investments - Summar
Short-Term Investments - Summary of Short-Term Investments (Detail) - USD ($) $ in Thousands | Mar. 31, 2020 | Dec. 31, 2019 |
Schedule of Available-for-sale Securities [Line Items] | ||
Amortized Cost | $ 23,710 | $ 44,452 |
Gross Unrealized Gains | 43 | 9 |
Gross Unrealized Losses | (2) | |
Fair Value | 23,753 | 44,459 |
U.S Government-Sponsored Enterprise Securities [Member] | ||
Schedule of Available-for-sale Securities [Line Items] | ||
Amortized Cost | 16,455 | 20,456 |
Gross Unrealized Gains | 29 | 2 |
Gross Unrealized Losses | (1) | |
Fair Value | 16,484 | 20,457 |
U.S. Treasury Securities [Member] | ||
Schedule of Available-for-sale Securities [Line Items] | ||
Amortized Cost | 7,255 | 23,996 |
Gross Unrealized Gains | 14 | 7 |
Gross Unrealized Losses | (1) | |
Fair Value | $ 7,269 | $ 24,002 |
Short-Term Investments - Additi
Short-Term Investments - Additional Information (Detail) - USD ($) | 3 Months Ended | |
Mar. 31, 2020 | Mar. 31, 2019 | |
Investments Debt And Equity Securities [Abstract] | ||
Realized gains (losses) on short-term investments | $ 0 | $ 0 |
Other-than-temporary impairments recognized | $ 0 | $ 0 |
Fair Value of Financial Asset_3
Fair Value of Financial Assets and Liabilities - Schedule of Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) - USD ($) $ in Thousands | Mar. 31, 2020 | Dec. 31, 2019 |
Liabilities: | ||
Derivative liability | $ 3 | $ 3 |
Fair Value, Measurements, Recurring [Member] | ||
Assets: | ||
Total assets | 56,626 | 68,365 |
Liabilities: | ||
Derivative liability | 3 | 3 |
Fair Value, Measurements, Recurring [Member] | Money Market Funds [Member] | ||
Assets: | ||
Cash equivalents | 32,873 | 23,906 |
Fair Value, Measurements, Recurring [Member] | U.S Government-Sponsored Enterprise Securities [Member] | ||
Assets: | ||
Short-term investments | 16,484 | 20,457 |
Fair Value, Measurements, Recurring [Member] | U.S. Treasury Securities [Member] | ||
Assets: | ||
Short-term investments | 7,269 | 24,002 |
Fair Value, Measurements, Recurring [Member] | Level 1 [Member] | ||
Assets: | ||
Total assets | 32,873 | 23,906 |
Fair Value, Measurements, Recurring [Member] | Level 1 [Member] | Money Market Funds [Member] | ||
Assets: | ||
Cash equivalents | 32,873 | 23,906 |
Fair Value, Measurements, Recurring [Member] | Level 2 [Member] | ||
Assets: | ||
Total assets | 23,753 | 44,459 |
Fair Value, Measurements, Recurring [Member] | Level 2 [Member] | U.S Government-Sponsored Enterprise Securities [Member] | ||
Assets: | ||
Short-term investments | 16,484 | 20,457 |
Fair Value, Measurements, Recurring [Member] | Level 2 [Member] | U.S. Treasury Securities [Member] | ||
Assets: | ||
Short-term investments | 7,269 | 24,002 |
Fair Value, Measurements, Recurring [Member] | Level 3 [Member] | ||
Liabilities: | ||
Derivative liability | $ 3 | $ 3 |
Fair Value of Financial Asset_4
Fair Value of Financial Assets and Liabilities - Additional Information (Detail) - USD ($) | 3 Months Ended | |
Mar. 31, 2020 | Dec. 31, 2019 | |
Fair Value Disclosures [Abstract] | ||
Transfer of assets from level 1 to level 2 | $ 0 | $ 0 |
Transfer of assets from level 2 to level 1 | 0 | 0 |
Transfer of liabilities from level 1 to level 2 | 0 | 0 |
Transfer of liabilities from level 2 to level 1 | $ 0 | 0 |
Fair value determination model | Monte-Carlo simulation analysis | |
Fair value of derivative liability | $ 0 | $ 0 |
Prepaids and Other Current As_3
Prepaids and Other Current Assets - Schedule of Prepaids and Other Current Assets (Detail) - USD ($) $ in Thousands | Mar. 31, 2020 | Dec. 31, 2019 |
Prepaid Expense And Other Assets Current [Abstract] | ||
Prepaid clinical, manufacturing and scientific expenses | $ 429 | $ 767 |
Prepaid insurance expenses | 1,629 | 125 |
Other prepaid expenses and other current assets | 431 | 512 |
Prepaids and other current assets | $ 2,489 | $ 1,404 |
Accrued Expenses - Schedule of
Accrued Expenses - Schedule of Accrued Expenses (Detail) - USD ($) $ in Thousands | Mar. 31, 2020 | Dec. 31, 2019 |
Payables And Accruals [Abstract] | ||
Accrued research and development expenses | $ 3,127 | $ 3,186 |
Accrued payroll and related expenses | 1,118 | 3,203 |
Accrued professional fees | 429 | 397 |
Accrued other | 51 | 78 |
Total accrued expenses | $ 4,725 | $ 6,864 |
Short-Term Borrowings - Additio
Short-Term Borrowings - Additional Information (Detail) $ in Thousands | 3 Months Ended |
Mar. 31, 2020USD ($) | |
Short Term Debt [Line Items] | |
Short-term borrowings | $ 1,099 |
Finance And Security Agreement | |
Short Term Debt [Line Items] | |
Short-term borrowings | $ 1,100 |
Agreement commencement date | Feb. 27, 2020 |
Debt instrument, term | 10 months |
Short-term debt, annual interest rate | 2.59% |
Debt instrument, maturity date | Dec. 11, 2020 |
Interest on short-term borrowings | $ 100 |
Stock-Based Compensation - Addi
Stock-Based Compensation - Additional Information (Detail) - USD ($) | Feb. 04, 2020 | Feb. 03, 2016 | Mar. 31, 2020 | Mar. 31, 2019 | Jan. 01, 2020 | Dec. 31, 2019 | Dec. 31, 2016 |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | |||||||
Stock-based compensation | $ 578,000 | $ 970,000 | |||||
Stock option grants | 1,528,600 | ||||||
RSUs outstanding | 5,530,411 | 4,364,839 | |||||
Grant date fair value of options | $ 1,700,000 | ||||||
Weighted average grant date fair value | $ 1.10 | ||||||
Requisite service period | 4 years | ||||||
Bonus Restricted Stock Units (RSUs) [Member] | |||||||
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | |||||||
Stock-based compensation | $ 100,000 | ||||||
RSUs outstanding | 4,519 | ||||||
Nonemployees [Member] | |||||||
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | |||||||
Stock option grants | 0 | ||||||
Number of options unvested | 83,250 | ||||||
Nonemployees [Member] | Prior to 2013 [Member] | |||||||
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | |||||||
Option issued to purchase common stock | 203,964 | ||||||
Maximum [Member] | Bonus Restricted Stock Units (RSUs) [Member] | |||||||
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | |||||||
Awards requisite service period date | Aug. 4, 2020 | ||||||
Minimum [Member] | Bonus Restricted Stock Units (RSUs) [Member] | |||||||
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | |||||||
Awards requisite service period date | Feb. 4, 2020 | ||||||
2016 Plan [Member] | |||||||
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | |||||||
Common stock reserved for issuance | 1,581,839 | 4,441,627 | 1,563,498 | ||||
Common stock reserved for issuance, percentage of number of shares of common stock outstanding | 3.00% | ||||||
Unrecognized compensation cost related to the unvested stock-based awards | $ 5,500,000 | ||||||
Compensation cost not yet recognized, period for recognition | 2 years 6 months 18 days | ||||||
2016 Plan and 2008 Plan [Member] | |||||||
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | |||||||
Common stock reserved for issuance | 9,972,038 | ||||||
2016 ESPP [Member] | |||||||
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | |||||||
Common stock reserved for issuance | 138,757 | 580,742 | |||||
Common stock reserved for issuance, percentage of number of shares of common stock outstanding | 1.00% | ||||||
Common stock available for issuance | 138,757 | ||||||
Number of shares issued | 31,027 | ||||||
2016 ESPP [Member] | Maximum [Member] | |||||||
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | |||||||
Stock-based compensation | $ 100,000 |
Stock-Based Compensation - Summ
Stock-Based Compensation - Summary of Restricted Stock Unit Activity (Detail) - Bonus Restricted Stock Units (RSUs) [Member] | 3 Months Ended |
Mar. 31, 2020$ / sharesshares | |
Number of Shares | |
Granted | 4,519 |
Unvested balance at March 31, 2020 | 4,519 |
Weighted Average Grant Date Fair Value | |
Granted | $ / shares | $ 1.77 |
Stock-Based Compensation - Su_2
Stock-Based Compensation - Summary of Stock-Based Compensation Expense, Including Shares Issued to Nonemployee for Consulting Services (Detail) - USD ($) $ in Thousands | 3 Months Ended | |
Mar. 31, 2020 | Mar. 31, 2019 | |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | ||
Total Stock-based compensation expense | $ 578 | $ 970 |
Research and Development [Member] | ||
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | ||
Total Stock-based compensation expense | 230 | 370 |
General and Administrative [Member] | ||
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | ||
Total Stock-based compensation expense | $ 348 | $ 600 |
Stock-Based Compensation - Su_3
Stock-Based Compensation - Summary of Stock Option Activity (Detail) - USD ($) $ / shares in Units, $ in Thousands | 3 Months Ended | 12 Months Ended |
Mar. 31, 2020 | Dec. 31, 2019 | |
Number of Shares | ||
Outstanding at December 31, 2019 | 4,364,839 | |
Granted | 1,528,600 | |
Forfeited | (363,028) | |
Outstanding at March 31, 2020 | 5,530,411 | 4,364,839 |
Exercisable at March 31, 2020 | 2,509,969 | |
Vested and expected to vest at March 31, 2020 | 5,447,161 | |
Weighted Average Exercise Price Per Share | ||
Outstanding at December 31, 2019 | $ 5.30 | |
Granted | 1.57 | |
Forfeited | 6.34 | |
Outstanding at March 31, 2020 | 4.20 | $ 5.30 |
Exercisable at March 31, 2020 | 5.79 | |
Vested and expected to vest at March 31, 2020 | $ 4.23 | |
Weighted Average Remaining Contractual Term, Outstanding | 7 years 10 months 6 days | 7 years 3 months 25 days |
Weighted Average Remaining Contractual Term, Exercisable at March 31, 2020 | 6 years 5 months 23 days | |
Weighted Average Remaining Contractual Term, Vested and expected to vest at March 31, 2020 | 7 years 11 months 15 days | |
Aggregate Intrinsic Value, Outstanding | $ 14 | $ 132 |
Aggregate Intrinsic Value, Exercisable at March 31, 2020 | 5 | |
Aggregate Intrinsic Value, Vested and expected to vest at March 31, 2020 | $ 14 |
Significant Agreements - Additi
Significant Agreements - Additional Information (Detail) - USD ($) $ in Thousands | 1 Months Ended | 3 Months Ended | ||
Feb. 28, 2019 | Mar. 31, 2019 | Mar. 31, 2020 | Dec. 31, 2018 | |
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items] | ||||
Revenue | $ 5,000 | |||
Genentech [Member] | ||||
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items] | ||||
Nonrefundable cash payment | $ 5,000 | $ 5,000 | ||
Future milestone payment | $ 96,000 | |||
Revenue | $ 5,000 |
Income Taxes - Additional Infor
Income Taxes - Additional Information (Detail) - USD ($) | 3 Months Ended | |
Mar. 31, 2020 | Mar. 31, 2019 | |
Income Tax Disclosure [Abstract] | ||
Federal income tax benefit | $ 0 | $ 0 |
State income tax benefit | $ 0 | $ 0 |
Net Loss per Share - Schedule o
Net Loss per Share - Schedule of Basic and Diluted Net Loss per Share (Detail) - USD ($) $ / shares in Units, $ in Thousands | 3 Months Ended | |
Mar. 31, 2020 | Mar. 31, 2019 | |
Numerator: | ||
Net loss | $ (9,878) | $ (14,418) |
Denominator: | ||
Weighted average common shares outstanding—basic and diluted | 52,146,633 | 50,976,907 |
Net loss per share—basic and diluted | $ (0.19) | $ (0.28) |
Net Loss per Share - Schedule_2
Net Loss per Share - Schedule of Antidilutive Securities Excluded from Computation of Diluted Weighted-average Shares Outstanding (Detail) - shares | 3 Months Ended | |
Mar. 31, 2020 | Mar. 31, 2019 | |
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] | ||
Potentially dilutive securities outstanding | 5,534,930 | 4,564,427 |
Options to Purchase Common Stock [Member] | ||
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] | ||
Potentially dilutive securities outstanding | 5,530,411 | 4,564,427 |
Restricted Stock Units [Member] | ||
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] | ||
Potentially dilutive securities outstanding | 4,519 |
Leases - Additional Information
Leases - Additional Information (Detail) - USD ($) $ in Thousands | Mar. 31, 2020 | Dec. 31, 2019 | Jan. 19, 2018 |
Leases [Abstract] | |||
Operating lease, initial term | 10 years | ||
Operating lease, option to extend additional term | 7 years | ||
Operating lease assets | $ 12,318 | $ 12,631 |
Leases - Elements of Lease Expe
Leases - Elements of Lease Expense (Detail) - USD ($) $ in Thousands | 3 Months Ended | |
Mar. 31, 2020 | Mar. 31, 2019 | |
Lease cost | ||
Operating lease cost | $ 462 | $ 462 |
Variable lease cost | 103 | 137 |
Total lease cost | 565 | 599 |
Other information | ||
Operating cash flows used for operating leases | 425 | 414 |
Operating lease liabilities arising from obtaining right-of-use assets | $ 12,921 | $ 14,000 |
Weighted-average remaining lease term | 8 years | 9 years |
Weighted-average discount rate | 4.50% | 4.50% |
Leases - Schedule of Future Lea
Leases - Schedule of Future Lease Payments under Noncancelable Leases (Detail) $ in Thousands | Mar. 31, 2020USD ($) |
Leases [Abstract] | |
2020 | $ 1,308 |
2021 | 1,780 |
2022 | 1,829 |
2023 | 1,880 |
2024 | 1,931 |
Thereafter | 6,825 |
Total lease payments | 15,553 |
Less: imputed interest | (2,632) |
Total operating lease liabilities | $ 12,921 |