Document and Entity Information
Document and Entity Information - shares | 6 Months Ended | |
Jun. 30, 2019 | Aug. 01, 2019 | |
Document And Entity Information [Abstract] | ||
Document Type | 10-Q | |
Amendment Flag | false | |
Document Period End Date | Jun. 30, 2019 | |
Document Fiscal Year Focus | 2019 | |
Document Fiscal Period Focus | Q2 | |
Trading Symbol | SLDB | |
Entity Registrant Name | Solid Biosciences Inc. | |
Entity Current Reporting Status | Yes | |
Entity Central Index Key | 0001707502 | |
Current Fiscal Year End Date | --12-31 | |
Entity Filer Category | Non-accelerated Filer | |
Entity Shell Company | false | |
Entity Small Business | false | |
Entity Emerging Growth Company | true | |
Entity Ex Transition Period | true | |
Entity Common Stock, Shares Outstanding | 46,001,329 | |
Entity File Number | 001-38360 | |
Entity Tax Identification Number | 900943402 | |
Entity Address, Address Line One | 141 Portland Street, Fifth Floor | |
Entity Address, City or Town | Cambridge | |
Entity Address, State or Province | MA | |
Entity Address, Postal Zip Code | 02139 | |
City Area Code | 617 | |
Local Phone Number | 337-4680 |
Condensed Consolidated Balance
Condensed Consolidated Balance Sheets - USD ($) $ in Thousands | Jun. 30, 2019 | Dec. 31, 2018 |
Current assets: | ||
Cash and cash equivalents | $ 51,836 | $ 86,366 |
Available-for-sale-securities | 15,550 | 36,098 |
Prepaid expenses and other current assets | 10,935 | 6,175 |
Total current assets | 78,321 | 128,639 |
Property and equipment, net | 11,829 | 10,422 |
Operating lease, right-of-use assets | 5,618 | |
Other non-current assets | 209 | 209 |
Restricted cash | 327 | 327 |
Total assets | 96,304 | 139,597 |
Current liabilities: | ||
Accounts payable | 5,600 | 3,691 |
Accrued expenses | 6,007 | 8,235 |
Operating lease liabilities | 1,610 | |
Finance lease liabilities | 176 | 173 |
Other current liabilities | 278 | 382 |
Total current liabilities | 13,671 | 12,481 |
Operating lease liabilities, excluding current portion | 5,309 | |
Finance lease liabilities, excluding current portion | 829 | 859 |
Other non-current liabilities | 1,074 | |
Total liabilities | 19,809 | 14,414 |
Commitments and contingencies (Note 11) | ||
Preferred stock, $0.001 par value; 10,000,000 shares authorized at June 30, 2019 and December 31, 2018; no shares issued and outstanding at June 30, 2019 and December 31, 2018 | ||
Common stock, $0.001 par value; 300,000,000 shares authorized at June 30, 2019 and December 31, 2018; 35,398,894 shares issued and outstanding at June 30, 2019 and 35,432,460 shares issued and outstanding at December 31, 2018 | 35 | 35 |
Additional paid-in capital | 331,620 | 324,209 |
Accumulated other comprehensive gain (loss) | 3 | (5) |
Accumulated deficit | (255,163) | (199,056) |
Total stockholders’ equity | 76,495 | 125,183 |
Total liabilities and stockholders’ equity | $ 96,304 | $ 139,597 |
Condensed Consolidated Balanc_2
Condensed Consolidated Balance Sheets (Parenthetical) - $ / shares | Jun. 30, 2019 | Dec. 31, 2018 |
Statement Of Financial Position [Abstract] | ||
Preferred stock, par value | $ 0.001 | $ 0.001 |
Preferred stock, shares authorized | 10,000,000 | 10,000,000 |
Preferred stock, shares issued | 0 | 0 |
Preferred stock, shares outstanding | 0 | 0 |
Common stock, par value | $ 0.001 | $ 0.001 |
Common stock, shares authorized | 300,000,000 | 300,000,000 |
Common stock, shares issued | 35,398,894 | 35,432,460 |
Common stock, shares outstanding | 35,398,894 | 35,432,460 |
Condensed Consolidated Statemen
Condensed Consolidated Statements of Operations - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended | ||
Jun. 30, 2019 | Jun. 30, 2018 | Jun. 30, 2019 | Jun. 30, 2018 | |
Income Statement [Abstract] | ||||
Revenue | $ 0 | $ 0 | $ 0 | $ 0 |
Operating expenses: | ||||
Research and development | 21,610 | 13,594 | 44,879 | 25,523 |
General and administrative | 5,359 | 4,584 | 12,392 | 8,628 |
Total operating expenses | 26,969 | 18,178 | 57,271 | 34,151 |
Loss from operations | (26,969) | (18,178) | (57,271) | (34,151) |
Other income (expense): | ||||
Interest income | 367 | 80 | 875 | 145 |
Other income | 77 | 118 | 289 | 149 |
Total other income (expense), net | 444 | 198 | 1,164 | 294 |
Net loss | $ (26,525) | $ (17,980) | $ (56,107) | $ (33,857) |
Net loss per share attributable to common stockholders, basic and diluted | $ (0.76) | $ (0.52) | $ (1.61) | $ (1.06) |
Weighted average shares of common stock outstanding, basic and diluted | 34,843,344 | 34,449,758 | 34,810,101 | 31,916,295 |
Condensed Consolidated Statem_2
Condensed Consolidated Statements of Comprehensive Loss - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended | ||
Jun. 30, 2019 | Jun. 30, 2018 | Jun. 30, 2019 | Jun. 30, 2018 | |
Statement Of Income And Comprehensive Income [Abstract] | ||||
Net loss | $ (26,525) | $ (17,980) | $ (56,107) | $ (33,857) |
Other comprehensive loss: | ||||
Unrealized gain (loss) on available-for-sale securities | (4) | 13 | 8 | 3 |
Comprehensive loss | $ (26,529) | $ (17,967) | $ (56,099) | $ (33,854) |
Condensed Consolidated Statem_3
Condensed Consolidated Statements of Changes in Stockholders' Equity/(Deficit) - USD ($) $ in Thousands | Total | Series A, B, C and D Common Units [Member] | Common Stock [Member] | Additional Paid In Capital [Member] | Accumulated Other Comprehensive Income (Loss) [Member] | Accumulated Deficit [Member] | Series 2 Senior Preferred Units [Member] | Series 1 Senior Preferred Units [Member] | Junior Preferred Units [Member] |
Beginning balance at Dec. 31, 2017 | $ (59,257) | $ 65,014 | $ (13) | $ (124,258) | $ 55,002 | $ 25,000 | $ 44,177 | ||
Beginning balance, units at Dec. 31, 2017 | 19,438,552 | 4,886,000 | 2,500,000 | 4,414,356 | |||||
Conversion of units into shares of common stock, value | 124,179 | $ (65,180) | $ 26 | $ 189,333 | $ (55,002) | $ (25,000) | $ (44,177) | ||
Conversion of units into shares of common stock, units | (19,429,620) | 26,498,559 | (4,886,000) | (2,500,000) | (4,414,356) | ||||
Issuance of common stock upon initial public offering, net of issuance costs of $4,592 | 129,096 | $ 9 | 129,087 | ||||||
Issuance of common stock upon initial public offering, net of issuance costs of $4,592, shares | 8,984,375 | ||||||||
Equity-based compensation | 2,128 | $ 166 | 1,962 | ||||||
Net loss | (33,857) | (33,857) | |||||||
Repurchase of common units/ shares of common stock | (8,932) | (38,142) | |||||||
Unrealized gain (loss) on available-for-sale securities | 3 | 3 | |||||||
Ending balance at Jun. 30, 2018 | 162,292 | $ 35 | 320,382 | (10) | (158,115) | ||||
Ending balance, units at Jun. 30, 2018 | 35,444,792 | ||||||||
Beginning balance at Mar. 31, 2018 | 178,950 | $ 35 | 319,073 | (23) | (140,135) | ||||
Beginning balance, units at Mar. 31, 2018 | 35,476,892 | ||||||||
Equity-based compensation | 1,309 | 1,309 | |||||||
Net loss | (17,980) | (17,980) | |||||||
Repurchase of common units/ shares of common stock | (32,100) | ||||||||
Unrealized gain (loss) on available-for-sale securities | 13 | 13 | |||||||
Ending balance at Jun. 30, 2018 | 162,292 | $ 35 | 320,382 | (10) | (158,115) | ||||
Ending balance, units at Jun. 30, 2018 | 35,444,792 | ||||||||
Beginning balance at Dec. 31, 2018 | 125,183 | $ 35 | 324,209 | (5) | (199,056) | ||||
Beginning balance, units at Dec. 31, 2018 | 35,432,460 | ||||||||
Equity-based compensation | 7,411 | 7,411 | |||||||
Net loss | (56,107) | (56,107) | |||||||
Repurchase of common units/ shares of common stock | (33,566) | ||||||||
Unrealized gain (loss) on available-for-sale securities | 8 | 8 | |||||||
Ending balance at Jun. 30, 2019 | 76,495 | $ 35 | 331,620 | 3 | (255,163) | ||||
Ending balance, units at Jun. 30, 2019 | 35,398,894 | ||||||||
Beginning balance at Mar. 31, 2019 | 99,113 | $ 35 | 327,709 | 7 | (228,638) | ||||
Beginning balance, units at Mar. 31, 2019 | 35,414,914 | ||||||||
Equity-based compensation | 3,911 | 3,911 | |||||||
Net loss | (26,525) | (26,525) | |||||||
Repurchase of common units/ shares of common stock | (16,020) | ||||||||
Unrealized gain (loss) on available-for-sale securities | (4) | (4) | |||||||
Ending balance at Jun. 30, 2019 | $ 76,495 | $ 35 | $ 331,620 | $ 3 | $ (255,163) | ||||
Ending balance, units at Jun. 30, 2019 | 35,398,894 |
Condensed Consolidated Statem_4
Condensed Consolidated Statements of Changes in Stockholders' Equity/(Deficit) (Parenthetical) $ in Thousands | 6 Months Ended |
Jun. 30, 2018USD ($) | |
Statement Of Financial Position [Abstract] | |
Net issuance costs, issuance of common stock upon initial public offering | $ 4,592 |
Condensed Consolidated Statem_5
Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands | 6 Months Ended | |
Jun. 30, 2019 | Jun. 30, 2018 | |
Cash flows from operating activities: | ||
Net loss | $ (56,107) | $ (33,857) |
Adjustments to reconcile net loss to net cash used in operating activities: | ||
Amortization of (discount)/premium on available-for-sale securities | (235) | (34) |
Equity-based compensation expense | 7,411 | 2,128 |
Depreciation expense | 1,254 | 540 |
(Gain) / loss on sale of property and equipment | 6 | |
Changes in operating assets and liabilities: | ||
Prepaid expenses and other current and non-current assets | (4,301) | (424) |
Accounts payable | 2,437 | (1,057) |
Accrued expenses and other current and non-current liabilities | (2,687) | (805) |
Net cash used in operating activities | (52,228) | (33,503) |
Cash flows from investing activities: | ||
Purchases of property and equipment | (3,092) | (4,217) |
Proceeds from sale and maturities of available-for-sale securities | 43,349 | 13,440 |
Purchases of available-for-sale securities | (22,559) | (13,324) |
Net cash provided by (used in) investing activities | 17,698 | (4,101) |
Cash flows from financing activities: | ||
Proceeds from initial public offering of common stock, net of commissions and underwriting discounts | 133,688 | |
Payment of deferred offering costs | (2,168) | |
Net cash provided by financing activities | 131,520 | |
Net (decrease) increase in cash, cash equivalents and restricted cash | (34,530) | 93,916 |
Cash, cash equivalents, and restricted cash at beginning of period | 86,693 | 52,145 |
Cash, cash equivalents, and restricted cash at end of period | 52,163 | 146,061 |
Supplemental disclosure of non-cash investing and financing activities: | ||
Property and equipment included in accounts payable and accruals | 395 | 715 |
Operating lease liabilities arising from obtaining right-of-use asset | $ 1,629 | |
Series A, B, C and D Common Units [Member] | ||
Supplemental disclosure of non-cash investing and financing activities: | ||
Conversion of units into shares of common stock | 65,180 | |
Series 2 Senior Preferred Units [Member] | ||
Supplemental disclosure of non-cash investing and financing activities: | ||
Conversion of units into shares of common stock | 55,002 | |
Series 1 Senior Preferred Units [Member] | ||
Supplemental disclosure of non-cash investing and financing activities: | ||
Conversion of units into shares of common stock | 25,000 | |
Junior Preferred Units [Member] | ||
Supplemental disclosure of non-cash investing and financing activities: | ||
Conversion of units into shares of common stock | $ 44,177 |
Nature of the Business and Basi
Nature of the Business and Basis of Presentation | 6 Months Ended |
Jun. 30, 2019 | |
Accounting Policies [Abstract] | |
Nature of the Business and Basis of Presentation | 1. Nature of the Business and Basis of Presentation Nature of Business Solid Biosciences Inc. (the “Company”) was organized in March 2013 under the name SOLID Ventures Management, LLC. In October 2013, the Company changed its name to Solid Ventures, LLC and in June 2015, the Company changed its name to Solid Biosciences, LLC. The Company operated as a Delaware limited liability company under the name Solid Biosciences, LLC until immediately prior to the effectiveness of its registration statement on Form S-1 on January 25, 2018, at which time it completed a statutory corporate conversion into a Delaware corporation (the “Corporate Conversion”) and changed its name to Solid Biosciences Inc. As a result of the Corporate Conversion, all of the Series 1 and 2 Senior Preferred Units, Junior Preferred Units, Series A, B, C and D Common Units of Solid Biosciences, LLC converted into shares of common stock of Solid Biosciences Inc. on a one-for-0.8485 basis and all of the unit holders of Solid Biosciences, LLC became holders of common stock of Solid Biosciences Inc. The Company’s mission is to cure Duchenne muscular dystrophy (“DMD”), a genetic muscle-wasting disease predominantly affecting boys. It is caused by mutations in the dystrophin gene, which result in the absence or near-absence of dystrophin protein. Dystrophin protein works to strengthen muscle fibers and protect them from daily wear and tear. Without functioning dystrophin and certain associated proteins, muscles suffer excessive damage from normal daily activities and are unable to regenerate, leading to the build-up of fibrotic, or scar, and fat tissue. The Company’s lead product candidate, SGT-001, is a gene transfer under development to restore functional dystrophin protein expression in patients’ muscles. SGT-001 has been granted Rare Pediatric Disease Designation and Fast Track in the United States and Orphan Drug Designations in both the United States and European Union. The Company filed an Investigational New Drug application (“IND”) in September 2017 and initiated a Phase I/II clinical trial for SGT-001 in the United States during the fourth quarter of 2017, which is called IGNITE DMD. The Company is subject to risks and uncertainties common to early-stage companies in the biotechnology industry, including, but not limited to, development by competitors of new technological innovations, dependence on licenses, protection of proprietary technology, dependence on key personnel, compliance with government regulations and the need to obtain additional financing to fund operations. Product candidates currently under development will require significant additional research and development efforts, including extensive pre-clinical studies and clinical trials and regulatory approval, prior to commercialization. These efforts require significant amounts of additional capital, adequate personnel infrastructure and extensive compliance and reporting capabilities. The Company’s product candidates are in development. There can be no assurance that the Company’s research and development will be successfully completed, that adequate protection for the Company’s intellectual property will be obtained, that any products developed will obtain necessary government regulatory approval or that any approved products will be commercially viable. Even if the Company’s product development efforts are successful, it is uncertain when, if ever, the Company will generate significant revenue from product sales. The Company operates in an environment of rapid change in technology and substantial competition from, among others, other pharmaceutical and biotechnology companies. In addition, the Company is dependent upon the services of its employees, partners and consultants. Liquidity The accompanying condensed consolidated financial statements have been prepared on a basis that assumes the Company will continue as a going concern and which contemplates the realization of assets and satisfaction of liabilities and commitments in the ordinary course of business. Through June 30, 2019, the Company has funded its operations primarily with the proceeds from the sale of redeemable preferred units and member units in private placements and its initial public offering. On July 30, 2019, the Company issued and sold in a private placement (i) 10,607,525 shares of its common stock at a price per share of $4.65 and (ii) 2,295,699 pre-funded warrants to purchase shares of its common stock at a price per warrant of $4.64. Each pre-funded warrant is exercisable for one share of common stock at an exercise price of $0.01 and the pre-funded warrants have no expiration date. The Company received gross proceeds from the private placement of $60,000, before deducting placement agent fees of $1,800. In accordance with Accounting Standards Codification (“ASC”) 205-40, Going Concern, the Company has evaluated whether there are conditions and events, considered in the aggregate, that raise substantial doubt about the Company’s ability to continue as a going concern within one year after the date the financial statements are issued or shorty thereafter. As of June 30, 2019, the Company had an accumulated deficit of $255,163. During the three and six months ended June 30, 2019, the Company incurred a net loss of $26,525 and $56,107, respectively, and the Company used $52,228 of cash in operations for the six months ended June 30, 2019. The Company has incurred recurring losses from operations since inception. The Company expects to continue to generate operating losses in the foreseeable future. The Company currently expects that its cash, cash equivalents and available-for-sale securities of $67,386 as of June 30, 2019, together with the net proceeds of $58,200 from the Company’s July 30, 2019 private placement, will be sufficient to fund its operating expenses and capital requirements, based upon its current operating plan, into the fourth quarter of 2020. In accordance with the requirements of ASC 205-40, the Company determined that there is substantial doubt about the Company’s ability to continue as a going concern within twelve months of the issuance date of these financial statements. The financial statements do not include any adjustments that might result from the outcome of this uncertainty. Although the Company has been successful in raising capital in the past, there is no assurance that it will be successful in obtaining such additional financing on terms acceptable to the Company, if at all, nor is it considered probable under the accounting standards. As such, under the requirements of ASC 205-40, management may not consider the potential for future capital raises or management plans to reduce costs that are not considered probable in its assessment of the Company’s ability to meet its obligations for the next twelve months. If the Company is unable to obtain funding, the Company would be forced to delay, reduce or eliminate some or all of its research and development programs, pre-clinical and clinical testing or commercialization efforts, which could adversely affect its business prospects. The accompanying condensed consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America (“GAAP”). The accompanying condensed consolidated financial statements include the accounts of the Company and its wholly owned or controlled subsidiaries. All intercompany accounts and transactions have been eliminated. In the opinion of management, the Company’s accompanying unaudited condensed consolidated financial statements (condensed consolidated financial statements) include all adjustments, consisting of normal recurring accruals, necessary for a fair statement of the Company’s financial statements for interim periods in accordance with GAAP. The information included in this quarterly report on Form 10-Q should be read in conjunction with the Company’s consolidated financial statements and the accompanying notes included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2018. The year-end condensed consolidated balance sheet data presented for comparative purposes was derived from the Company’s audited financial statements, but does not include all disclosures required by GAAP. |
Summary of Significant Accounti
Summary of Significant Accounting Policies | 6 Months Ended |
Jun. 30, 2019 | |
Accounting Policies [Abstract] | |
Summary of Significant Accounting Policies | 2. Summary of Significant Accounting Policies Use of Estimates The preparation of the Company’s condensed consolidated financial statements in conformity with GAAP requires management to make estimates, judgments and assumptions that affect the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities at the date of the condensed consolidated financial statements and the reported amounts of expenses during the reporting periods. Significant estimates and assumptions reflected in these condensed consolidated financial statements include, but are not limited to, the recognition of research and development expenses and equity-based compensation. 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 the Company’s estimates. Cash Equivalents The Company considers all short-term, highly liquid investments with original maturities of 90 days or less at acquisition date to be cash equivalents. Restricted Cash The Company held restricted cash of $327 in separate restricted bank accounts as security deposits for leases of the Company’s facilities as of June 30, 2019 and December 31, 2018. The Company has included restricted cash of $327 as a non-current asset as of June 30, 2019 and December 31, 2018. A reconciliation of the amounts of cash and cash equivalents and restricted cash from the cash flow statement to the balance sheet is as follows: June 30, 2019 December 31, 2018 Cash and cash equivalents as presented on balance sheet $ 51,836 $ 86,366 Restricted cash, non-current, as presented on balance sheet 327 327 Cash and cash equivalents and restricted cash as presented on cash flow statement $ 52,163 $ 86,693 Available-for-Sale Securities Available-for-sale securities consist of investments with original maturities greater than 90 days at acquisition date. The Company has classified its investments with maturities beyond one year as short term, based on their highly liquid nature and because such available-for-sale securities represent the investment of cash that is available for current operations. The Company classifies all of its investments as available-for-sale securities. The Company’s investments are measured and reported at fair value using quoted prices in active markets for similar securities. Unrealized gains and losses on available-for-sale debt securities are reported as a separate component of stockholders’ equity. The cost of securities sold is determined on a specific identification basis, and realized gains and losses are included in other income (expense) within the condensed consolidated statement of operations. If any adjustment to fair value reflects a decline in the value of the investment that the Company considers to be “other than temporary,” the Company reduces the investment to fair value through a charge to the condensed consolidated statement of operations. No such adjustments were necessary during the periods presented. Concentration of Credit Risk and of Significant Suppliers Financial instruments that potentially expose the Company to concentrations of credit risk consist primarily of cash and cash equivalents. Periodically, the Company maintains deposits in accredited financial institutions in excess of federally insured limits. The Company maintains each of its cash balances with high-quality and accredited financial institutions and accordingly, such funds are not exposed to significant credit risk. The Company does not believe that it is subject to unusual credit risk beyond the normal credit risk associated with commercial banking relationships. The Company is dependent on third-party manufacturers to supply products for research and development activities of its programs, including clinical and pre-clinical testing. These programs could be adversely affected by a significant interruption in the supply of such drug substance products. Fair Value Measurements Certain assets and liabilities are carried at fair value under GAAP. Fair value is defined as the exchange price that would be received for an asset or paid to transfer a liability (an exit price) in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. Valuation techniques used to measure fair value must maximize the use of observable inputs and minimize the use of unobservable inputs. Financial assets and liabilities carried at fair value are to be classified and disclosed in one of the following three levels of the fair value hierarchy, of which the first two are considered observable and the last is considered unobservable: • Level 1—Quoted prices in active markets for identical assets or liabilities. • Level 2—Observable inputs (other than Level 1 quoted prices), such as quoted prices in active markets for similar assets or liabilities, quoted prices in markets that are not active for identical or similar assets or liabilities or other inputs that are observable or can be corroborated by observable market data. • Level 3—Unobservable inputs that are supported by little or no market activity and that are significant to determining the fair value of the assets or liabilities, including pricing models, discounted cash flow methodologies and similar techniques. The Company’s cash equivalents and available-for-sale securities are carried at fair value, determined according to the fair value hierarchy described above. See Note 3, Fair Value of Financial Assets and Liabilities Leases At inception of a contract, the Company determines if a contract meets the definition of a lease. A lease is a contract, or part of a contract, that conveys the right to control the use of identified property, plant, or equipment (an identified asset) for a period of time in exchange for consideration. The Company determines if the contract conveys the right to control the use of an identified asset for a period of time. The Company assesses throughout the period of use whether the Company has both of the following: (1) the right to obtain substantially all of the economic benefits from use of the identified asset and (2) the right to direct the use of the identified asset. This determination is reassessed if the terms of the contract are changed. Leases are classified as operating or finance leases based on the terms of the lease agreement and certain characteristics of the identified asset. Right-of-use assets and lease liabilities are recognized at the lease commencement date based on the present value of the minimum future lease payments. The Company’s policy is to not record leases with an original term of twelve months or less on the condensed consolidated balance sheets. The Company recognizes lease expense for these short-term leases on a straight-line basis over the lease term. Certain lease agreements include rental payments that are adjusted periodically for inflation or other variables. In addition to rent, the leases may require the Company to pay additional amounts for taxes, insurance, maintenance and other expenses, which are generally referred to as non-lease components. Such adjustments to rental payments and variable non-lease components are treated as variable lease payments and recognized in the period in which the obligation for these payments was incurred. Variable lease components and variable non-lease components are not measured as part of the right of use asset and liability. Only when lease components and their associated non-lease components are fixed are they accounted for as a single lease component and recognized as part of a right of use asset and liability. Total contract consideration is allocated to the combined fixed lease and non-lease components. Equity-Based Compensation In connection with the completion of the Company’s initial public offering, the Company adopted the 2018 Omnibus Incentive Plan, which provides for the issuance of share-based awards, including options to purchase common stock. The 2018 Omnibus Incentive Plan provides for the awarding of up to 5,001,000 shares of common stock for equity awards. The Company measures all stock options and other stock-based awards granted to employees, directors and non-employees based on the fair value on the date of the grant and recognizes compensation expense of those awards, over the requisite service period, which is generally the vesting period of the respective award. Forfeitures are accounted for as they occur. The Company applies the straight-line method of expense recognition to all awards with only service-based vesting conditions. The Company has not issued any awards with performance-based vesting conditions. For stock-based awards granted to non-employees, compensation expense is recognized over the period during which services are rendered by such non-employees until completed. The fair value of each stock option grant is estimated on the date of grant using the Black-Scholes option-pricing model. The Company historically has been a private company and lacks company-specific historical and implied volatility information. Therefore, it estimates its expected stock volatility based on the historical volatility of a publicly traded set of peer companies and expects to continue to do so until such time as it has adequate historical data regarding the volatility of its own traded stock price. For options with service-based vesting conditions, the expected term of the Company’s stock options has been determined utilizing the “simplified” method for awards that qualify as “plain-vanilla” options. The expected term of stock options granted to non-employees is equal to the contractual term of the option award. The risk-free interest rate is determined by reference to the U.S. Treasury yield curve in effect at the time of grant of the award for time periods approximately equal to the expected term of the award. Expected dividend yield is based on the fact that the Company has never paid cash dividends and does not expect to pay any cash dividends in the foreseeable future. The Company classifies stock-based compensation expense in its condensed consolidated statement of operations and comprehensive loss in the same manner in which the award recipient’s payroll costs are classified or in which the award recipient’s service payments are classified. Income Taxes Income taxes are accounted for under the asset and liability method. Under the asset and liability method, deferred tax assets and liabilities are recognized for the future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. The effect on deferred tax assets and liabilities of a change in tax rates is recognized in income in the period that includes the enactment date. The Company records valuation allowances to reduce deferred income tax assets to the amount that is more likely than not to be realized. The Company determines whether it is more likely than not that a tax position will be sustained upon examination. If it is not more likely than not that a position will be sustained, no amount of benefit attributable to the position is recognized. The tax benefit to be recognized of any tax position that meets the more likely than not recognition threshold is calculated as the largest amount that is more than 50% likely of being realized upon resolution of the contingency. Segment Data The Company manages its operations as a single segment for the purposes of assessing performance and making operating decisions. The Company’s singular focus is on developing treatments through gene therapy and other means for patients with DMD. All of the Company’s tangible assets are held in the United States. Comprehensive Loss Comprehensive loss includes net loss, as well as other changes in stockholders’ equity that result from transactions and economic events other than those with stockholders and members. The Company’s only element of other comprehensive loss in all periods presented was unrealized gains (losses) from available-for-sale securities. Net Loss per Share The Company follows the two-class method when computing net loss per share, as the Company has issued shares that meet the definition of participating securities. The two-class method determines net loss per share for each class of common and participating securities according to dividends declared or accumulated and participation rights in undistributed earnings. The two-class method requires income available to common stockholders for the period to be allocated between common and participating securities based upon their respective rights to receive dividends as if all income for the period had been distributed. Basic net loss per share attributable to common stockholders is computed by dividing the net loss attributable to common stockholders by the weighted average number of shares of common stock outstanding for the period. Diluted net loss attributable to common stockholders is computed by adjusting net loss attributable to common stockholders to reallocate undistributed earnings based on the potential impact of dilutive securities. Diluted net loss per share attributable to common stockholders is computed by dividing the diluted net loss attributable to common stockholders by the weighted average number of shares of common stock outstanding for the period, including potential dilutive shares of common stock assuming the dilutive effect of common stock equivalents. The Company’s participating securities contractually entitle the holders of such shares to participate in dividends but does not contractually require the holders of such shares to participate in losses of the Company. Accordingly, in periods in which the Company reports a net loss, such losses are not allocated to such participating securities. In periods in which the Company reports a net loss attributable to common stockholders, diluted net loss per share attributable to common stockholders is the same as basic net loss per share attributable to common stockholders, since dilutive shares of common stock are not assumed to have been issued if their effect is anti-dilutive. Contingencies Loss contingency provisions are recorded if the potential loss from any claim, asserted or unasserted, or legal proceeding is considered probable and the amount can be reasonably estimated, or a range of loss can be determined. These accruals represent the Company’s best estimate of probable loss. Disclosure also is provided when it is reasonably possible that a loss will be incurred or when it is reasonably possible that the amount of a loss will exceed the recorded provision. The Company reviews the status of each significant matter and assesses its potential financial exposure. Significant judgment is required in both the determination of probability and the determination as to whether an exposure is reasonably estimable. Because of uncertainties related to these matters, accruals are based only on the best information available at the time. As additional information becomes available, the Company reassesses the potential liability related to pending claims and may change its estimates. These changes in the estimates of the potential liabilities could have a material impact on the Company’s condensed consolidated results of operations and financial position. Recently Adopted Accounting Pronouncements The Company adopted Accounting Standards Update (“ASU”) No. 2016-02, Leases (Topic 842) Recently Issued Accounting Pronouncements In August 2018, the Financial Accounting Standards Board issued ASU No. 2018-13 , Fair Value Measurement (Topic 820): Disclosure Framework - Changes to the Disclosure Requirements for Fair Value Measurement |
Fair Value of Financial Assets
Fair Value of Financial Assets and Liabilities | 6 Months Ended |
Jun. 30, 2019 | |
Fair Value Disclosures [Abstract] | |
Fair Value of Financial Assets and Liabilities | 3. Fair Value of Financial Assets and Liabilities The following tables present information about the Company’s assets and liabilities that are measured at fair value on a recurring basis and indicate the level of the fair value hierarchy utilized to determine such fair values: Fair Value Measurements as of June 30, 2019 Using: Level 1 Level 2 Level 3 Total Assets: Cash equivalents $ — $ 21,337 $ — $ 21,337 Available-for-sale securities — 15,550 — 15,550 $ — $ 36,887 $ — $ 36,887 Fair Value Measurements as of December 31, 2018 Using: Level 1 Level 2 Level 3 Total Assets: Cash equivalents $ — $ 54,423 $ — $ 54,423 Available-for-sale securities — 36,098 — 36,098 $ — $ 90,521 $ — $ 90,521 As of June 30, 2019 and December 31, 2018, the fair values of the Company’s available-for-sale debt securities, which consisted of U.S. government agency securities, commercial paper and corporate bond securities, were determined using Level 2 inputs. During the six months ended June 30, 2019 and the year ended December 31, 2018, there were no transfers between Level 1, Level 2 and Level 3. The fair value of the Company’s cash, restricted cash, accounts payable, and accrued expenses and other current liabilities approximate their carrying value due to their short-term maturities. |
Available-for-Sale Securities
Available-for-Sale Securities | 6 Months Ended |
Jun. 30, 2019 | |
Investments Debt And Equity Securities [Abstract] | |
Available-for-Sale Securities | 4. Available-for-Sale Securities As of June 30, 2019 and December 31, 2018, the fair value of available-for-sale securities by type of security was as follows: June 30, 2019 Amortized Cost Gross Unrealized Gain Gross Unrealized Loss Fair Value Investments: U.S. government agency securities $ 6,016 $ 2 $ — $ 6,018 Corporate bond securities 9,531 2 (1 ) 9,532 $ 15,547 $ 4 $ (1 ) $ 15,550 December 31, 2018 Amortized Cost Gross Unrealized Gain Gross Unrealized Loss Fair Value Investments: U.S. government agency securities $ 13,543 $ — $ (2 ) $ 13,541 Corporate bond securities 12,860 2 (5 ) 12,857 Commercial paper 9,700 — — 9,700 $ 36,103 $ 2 $ (7 ) $ 36,098 The estimated fair value and amortized cost of the Company’s available-for-sale securities by contractual maturity are summarized as follows: June 30, 2019 December 31, 2018 Amortized Cost Fair Value Amortized Cost Fair Value Due in one year or less $ 15,547 $ 15,550 $ 36,103 $ 36,098 Total available-for-sale securities $ 15,547 $ 15,550 $ 36,103 $ 36,098 The weighted average maturity of the Company’s available-for-sale securities as of June 30, 2019 and December 31, 2018 was approximately 0.2 years and |
Property and Equipment
Property and Equipment | 6 Months Ended |
Jun. 30, 2019 | |
Property Plant And Equipment [Abstract] | |
Property and Equipment | 5. Property and Equipment Property and equipment consists of the following: June 30, 2019 December 31, 2018 Furniture and fixtures $ 203 $ 187 Laboratory equipment 8,622 5,998 Leasehold improvements 4,686 4,585 Computer equipment 467 166 Computer software 356 123 Construction in process 737 1,351 15,071 12,410 Less accumulated depreciation 3,242 1,988 $ 11,829 $ 10,422 Depreciation expense was $658 and $1,254 for the three and six months ended June 30, 2019, respectively, and $313 and $540 for the three and six months ended June 30, 2018, respectively. |
Prepaid Expenses and Other Curr
Prepaid Expenses and Other Current Assets | 6 Months Ended |
Jun. 30, 2019 | |
Deferred Costs Capitalized Prepaid And Other Assets Disclosure [Abstract] | |
Prepaid Expenses and Other Current Assets | 6. Prepaid Expenses and Other Current Assets Prepaid expenses and other current assets consist of the following: June 30, 2019 December 31, 2018 Prepaid research and development expenses $ 5,342 $ 4,365 Prepaid expenses and other assets 5,593 1,810 $ 10,935 $ 6,175 |
Accrued Expenses and Other Curr
Accrued Expenses and Other Current Liabilities | 6 Months Ended |
Jun. 30, 2019 | |
Payables And Accruals [Abstract] | |
Accrued Expenses and Other Current Liabilities | 7. Accrued Expenses and Other Current Liabilities Accrued expenses and other current liabilities consist of the following: June 30, 2019 December 31, 2018 Accrued research and development $ 4,055 $ 3,529 Accrued compensation 704 3,534 Accrued other 1,248 1,172 $ 6,007 $ 8,235 |
Equity-Based Compensation
Equity-Based Compensation | 6 Months Ended |
Jun. 30, 2019 | |
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract] | |
Equity-Based Compensation | 8. Equity-Based Compensation In connection with the closing of the Company’s initial public offering, the board of directors and stockholders approved the 2018 Omnibus Incentive Plan, which provides for the reservation of 5,001,000 shares of common stock for equity awards. During the three and six months ended June 30, 2019, the Company granted options for the purchase of 101,000 and 1,644,421 shares of common stock, respectively. The Company recorded equity-based compensation expense related to all of its share-based awards to employees and non-employees in the following captions within its condensed consolidated statements of operations: Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 Research and development $ 2,114 $ 1,084 $ 3,933 $ 1,716 General and administrative 1,797 225 3,478 412 Total $ 3,911 $ 1,309 $ 7,411 $ 2,128 |
Income Taxes
Income Taxes | 6 Months Ended |
Jun. 30, 2019 | |
Income Tax Disclosure [Abstract] | |
Income Taxes | 9. Income Taxes During the three and six months ended June 30, 2019 and 2018, the Company recorded no income tax benefits for the net operating losses incurred or for the research and development tax credits and orphan drug credits generated in each year due to its uncertainty of realizing a benefit from those items. The Company has provided a valuation allowance for the full amounts of its net deferred tax assets because, at June 30, 2019 and December 31, 2018, it was more likely than not that any future benefit from deductible temporary differences and net operating loss and tax credit carryforwards would not be realized. As of June 30, 2019 and December 31, 2018, the Company had not recorded any amounts for unrecognized tax benefits. The Company files income tax returns as prescribed by the tax laws of the jurisdictions in which it operates. In the normal course of business, the Company is subject to examination by federal and state jurisdictions, where applicable. There are currently no pending income tax examinations. The Company’s C-Corporation 2018 tax year is open under statute. Any tax credit or net operating loss carryforward can be adjusted in future periods after the respective year of generation’s statute of limitation has closed. |
Leases
Leases | 6 Months Ended |
Jun. 30, 2019 | |
Leases [Abstract] | |
Leases | 10. Leases The Company leases real estate, including laboratories and office space, and certain equipment related to its research and development. The Company’s leases have remaining lease terms ranging from one to six years. Certain leases include an option to renew, exercisable at the Company’s sole discretion, with renewal terms that can extend the lease for two years. The Company evaluated the renewal options in its leases to determine if it was reasonably certain that the renewal option would be exercised, and therefore should be included in the calculation of the operating lease assets and operating lease liabilities. Given the Company’s current business structure, uncertainty of future growth, and the associated impact to real estate, the Company concluded that it is not reasonably certain that any renewal options would be exercised. Therefore, the operating lease assets and lease liabilities only contemplate the initial lease terms. In January 2018, the Company executed a lease agreement for lab space in Cambridge, Massachusetts. The lease consists of approximately 9,500 square feet with an initial term of five years with the option to extend the term for one additional two year term. The future minimum rent commitment for the initial five-year term is approximately $3,000. In addition to rent, the lease requires the Company to pay additional amounts for taxes, insurance, maintenance and other operating expenses. In January 2018, the Company executed a lease agreement for office space in Cambridge, Massachusetts. The space serves as the Company’s corporate headquarters and consists of approximately 16,000 square feet. The term of the lease runs through February 2022. The future minimum rent commitment for the lease term is approximately $3,400. In addition to rent, the lease requires the Company to pay additional amounts for taxes, insurance, maintenance and other operating expenses. In November 2018, the Company entered into a 48-month capital lease for certain lab equipment to be used at its facility in Cambridge Massachusetts. The future minimum lease commitment for the lease term is approximately $1,266. In January 2019, the Company executed a lease agreement for additional office space in Cambridge, Massachusetts. The space serves as office space supporting the Company’s lab operations and consists of approximately 5,000 square feet. The term of the lease runs through January 2025. The future minimum rent commitment for the lease term is approximately $2,500. As of June 30, 2019, minimum future lease payments for these operating and finance leases were as follows: Finance Leases Operating Leases 2019 $ 138 $ 1,183 2020 276 2,408 2021 276 2,444 2022 276 1,424 2023 300 686 Thereafter — 778 Total 1,266 8,923 Less: Imputed Interest 261 2,004 Total Lease Liabilities $ 1,005 $ 6,919 As of December 31, 2018, minimum future lease payments for these operating and finance leases were as follows: Finance Leases Operating Leases 2019 $ 276 $ 1,934 2020 276 2,017 2021 276 2,056 2022 485 1,023 2023 — 278 Thereafter — - Total 1,313 7,308 The company recorded lease expense of $602 and $1,124 for the three and six months ended June 30, 2019, respectively. Short-term lease costs were not material for the three and six months ended June 30, 2019. Variable lease costs were not material for the three and six months ended June 30, 2019. The supplemental disclosure of cash flow information related to the Company’s leases and the weighted average remaining lease term and weighted average discount rate of the Company’s leases are as follows: For the Three Months Ended June 30, For the Six Months Ended June 30, 2019 2019 Other information Operating cash flows used for operating leases $ 318 $ 1,105 Operating lease liabilities arising from obtaining right-of-use-assets $ — $ 1,629 Finance lease liabilities arising from obtaining right-of-use assets $ — $ — Weighted-average remaining lease term (in years) Operating lease 3.9 3.9 Finance lease 3.8 3.8 Weighted-average discount rate Operating lease 12.3 % 12.3 % Finance lease 10.7 % 10.7 % |
Commitments and Contingencies
Commitments and Contingencies | 6 Months Ended |
Jun. 30, 2019 | |
Commitments And Contingencies Disclosure [Abstract] | |
Commitments and Contingencies | 11. Commitments and Contingencies Legal Proceedings On March 28, 2018, a purported stockholder of the Company, filed a putative class action complaint alleging violations of the federal securities laws, in the Business Litigation Section of the Superior Court of the Commonwealth of Massachusetts (Civil Action No. 1884-00984), against the Company, Ilan Ganot, Jennifer Ziolkowski, the Company’s directors and certain of the underwriters in the Company’s initial public offering. The plaintiff in this suit claims to represent purchasers of the Company’s common stock in or traceable to the Company’s January 25, 2018 initial public offering and seeks unspecified damages arising out of the alleged failure to disclose risks associated with toxicity and potential for adverse events related to the Company’s lead product candidate. On April 30, 2018, all defendants including the Company moved to stay the proceedings in favor of the prior-filed federal court securities class action. The plaintiff filed his opposition to this motion on May 14, 2018, and defendants filed a reply in support of their motion on May 24, 2018. After oral argument on June 13, 2018, the court issued an order on June 22, 2018 allowing the motion to stay and directing the parties to advise the court of the status of the federal court action every six months. On December 21, 2018, the parties filed a joint status report informing the court of the voluntary dismissal of the federal actions and of plaintiff’s intent to move to vacate the stay. On June 28, 2019, the plaintiff voluntarily dismissed his claims without prejudice. |
Net Loss per Share
Net Loss per Share | 6 Months Ended |
Jun. 30, 2019 | |
Earnings Per Share [Abstract] | |
Net Loss per Share | 12. Net Loss per Share Basic and diluted net loss per share attributable to common stockholders were calculated as follows: The numerator for basic and diluted net loss per share attributable to common stockholders is as follows: Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 Net loss attributable to common stockholders $ (26,525 ) $ (17,980 ) $ (56,107 ) $ (33,857 ) The denominator is as follows: Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 Weighted average shares of common stock outstanding, basic and diluted 34,843,344 34,449,758 34,810,101 31,916,295 Net loss per share attributable to common stockholders, basic and diluted is as follows: Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 Net loss per share attributable to common stockholders $ (0.76 ) $ (0.52 ) $ (1.61 ) $ (1.06 ) The following potential common stock equivalents, presented based on amounts outstanding at each period end, were excluded from the calculation of diluted net loss per share attributable to common stockholders for the periods indicated because including them would have had an anti-dilutive effect for the three and six months ended June 30: 2019 2018 Options to purchase shares of common stock 2,730,362 752,773 Unvested shares of common stock 523,687 951,066 3,254,049 1,703,839 |
Subsequent Events
Subsequent Events | 6 Months Ended |
Jun. 30, 2019 | |
Subsequent Events [Abstract] | |
Subsequent Events | 13. Subsequent Events On July 30, 2019, the Company issued and sold in a private placement (i) 10,607,525 shares of its common stock at a price per share of $4.65 and (ii) 2,295,699 pre-funded warrants to purchase shares of its common stock at a price per warrant of $4.64. Each pre-funded warrant is exercisable for one share of common stock at an exercise price of $0.01 and the pre-funded warrants have no expiration date. The Company received gross proceeds from the private placement of $60,000, before deducting placement agent fees and of $1,800. The securities were sold pursuant to a securities purchase agreement entered into between the Company and certain accredited investors on July 25, 2019. |
Summary of Significant Accoun_2
Summary of Significant Accounting Policies (Policies) | 6 Months Ended |
Jun. 30, 2019 | |
Accounting Policies [Abstract] | |
Use of Estimates | Use of Estimates The preparation of the Company’s condensed consolidated financial statements in conformity with GAAP requires management to make estimates, judgments and assumptions that affect the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities at the date of the condensed consolidated financial statements and the reported amounts of expenses during the reporting periods. Significant estimates and assumptions reflected in these condensed consolidated financial statements include, but are not limited to, the recognition of research and development expenses and equity-based compensation. 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 the Company’s estimates. |
Cash Equivalents | Cash Equivalents The Company considers all short-term, highly liquid investments with original maturities of 90 days or less at acquisition date to be cash equivalents. |
Restricted Cash | Restricted Cash The Company held restricted cash of $327 in separate restricted bank accounts as security deposits for leases of the Company’s facilities as of June 30, 2019 and December 31, 2018. The Company has included restricted cash of $327 as a non-current asset as of June 30, 2019 and December 31, 2018. A reconciliation of the amounts of cash and cash equivalents and restricted cash from the cash flow statement to the balance sheet is as follows: June 30, 2019 December 31, 2018 Cash and cash equivalents as presented on balance sheet $ 51,836 $ 86,366 Restricted cash, non-current, as presented on balance sheet 327 327 Cash and cash equivalents and restricted cash as presented on cash flow statement $ 52,163 $ 86,693 |
Available-for-Sale Securities | Available-for-Sale Securities Available-for-sale securities consist of investments with original maturities greater than 90 days at acquisition date. The Company has classified its investments with maturities beyond one year as short term, based on their highly liquid nature and because such available-for-sale securities represent the investment of cash that is available for current operations. The Company classifies all of its investments as available-for-sale securities. The Company’s investments are measured and reported at fair value using quoted prices in active markets for similar securities. Unrealized gains and losses on available-for-sale debt securities are reported as a separate component of stockholders’ equity. The cost of securities sold is determined on a specific identification basis, and realized gains and losses are included in other income (expense) within the condensed consolidated statement of operations. If any adjustment to fair value reflects a decline in the value of the investment that the Company considers to be “other than temporary,” the Company reduces the investment to fair value through a charge to the condensed consolidated statement of operations. No such adjustments were necessary during the periods presented. |
Concentration of Credit Risk and of Significant Suppliers | Concentration of Credit Risk and of Significant Suppliers Financial instruments that potentially expose the Company to concentrations of credit risk consist primarily of cash and cash equivalents. Periodically, the Company maintains deposits in accredited financial institutions in excess of federally insured limits. The Company maintains each of its cash balances with high-quality and accredited financial institutions and accordingly, such funds are not exposed to significant credit risk. The Company does not believe that it is subject to unusual credit risk beyond the normal credit risk associated with commercial banking relationships. The Company is dependent on third-party manufacturers to supply products for research and development activities of its programs, including clinical and pre-clinical testing. These programs could be adversely affected by a significant interruption in the supply of such drug substance products. |
Fair Value Measurements | Fair Value Measurements Certain assets and liabilities are carried at fair value under GAAP. Fair value is defined as the exchange price that would be received for an asset or paid to transfer a liability (an exit price) in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. Valuation techniques used to measure fair value must maximize the use of observable inputs and minimize the use of unobservable inputs. Financial assets and liabilities carried at fair value are to be classified and disclosed in one of the following three levels of the fair value hierarchy, of which the first two are considered observable and the last is considered unobservable: • Level 1—Quoted prices in active markets for identical assets or liabilities. • Level 2—Observable inputs (other than Level 1 quoted prices), such as quoted prices in active markets for similar assets or liabilities, quoted prices in markets that are not active for identical or similar assets or liabilities or other inputs that are observable or can be corroborated by observable market data. • Level 3—Unobservable inputs that are supported by little or no market activity and that are significant to determining the fair value of the assets or liabilities, including pricing models, discounted cash flow methodologies and similar techniques. The Company’s cash equivalents and available-for-sale securities are carried at fair value, determined according to the fair value hierarchy described above. See Note 3, Fair Value of Financial Assets and Liabilities |
Leases | Leases At inception of a contract, the Company determines if a contract meets the definition of a lease. A lease is a contract, or part of a contract, that conveys the right to control the use of identified property, plant, or equipment (an identified asset) for a period of time in exchange for consideration. The Company determines if the contract conveys the right to control the use of an identified asset for a period of time. The Company assesses throughout the period of use whether the Company has both of the following: (1) the right to obtain substantially all of the economic benefits from use of the identified asset and (2) the right to direct the use of the identified asset. This determination is reassessed if the terms of the contract are changed. Leases are classified as operating or finance leases based on the terms of the lease agreement and certain characteristics of the identified asset. Right-of-use assets and lease liabilities are recognized at the lease commencement date based on the present value of the minimum future lease payments. The Company’s policy is to not record leases with an original term of twelve months or less on the condensed consolidated balance sheets. The Company recognizes lease expense for these short-term leases on a straight-line basis over the lease term. Certain lease agreements include rental payments that are adjusted periodically for inflation or other variables. In addition to rent, the leases may require the Company to pay additional amounts for taxes, insurance, maintenance and other expenses, which are generally referred to as non-lease components. Such adjustments to rental payments and variable non-lease components are treated as variable lease payments and recognized in the period in which the obligation for these payments was incurred. Variable lease components and variable non-lease components are not measured as part of the right of use asset and liability. Only when lease components and their associated non-lease components are fixed are they accounted for as a single lease component and recognized as part of a right of use asset and liability. Total contract consideration is allocated to the combined fixed lease and non-lease components. |
Equity-Based Compensation | Equity-Based Compensation In connection with the completion of the Company’s initial public offering, the Company adopted the 2018 Omnibus Incentive Plan, which provides for the issuance of share-based awards, including options to purchase common stock. The 2018 Omnibus Incentive Plan provides for the awarding of up to 5,001,000 shares of common stock for equity awards. The Company measures all stock options and other stock-based awards granted to employees, directors and non-employees based on the fair value on the date of the grant and recognizes compensation expense of those awards, over the requisite service period, which is generally the vesting period of the respective award. Forfeitures are accounted for as they occur. The Company applies the straight-line method of expense recognition to all awards with only service-based vesting conditions. The Company has not issued any awards with performance-based vesting conditions. For stock-based awards granted to non-employees, compensation expense is recognized over the period during which services are rendered by such non-employees until completed. The fair value of each stock option grant is estimated on the date of grant using the Black-Scholes option-pricing model. The Company historically has been a private company and lacks company-specific historical and implied volatility information. Therefore, it estimates its expected stock volatility based on the historical volatility of a publicly traded set of peer companies and expects to continue to do so until such time as it has adequate historical data regarding the volatility of its own traded stock price. For options with service-based vesting conditions, the expected term of the Company’s stock options has been determined utilizing the “simplified” method for awards that qualify as “plain-vanilla” options. The expected term of stock options granted to non-employees is equal to the contractual term of the option award. The risk-free interest rate is determined by reference to the U.S. Treasury yield curve in effect at the time of grant of the award for time periods approximately equal to the expected term of the award. Expected dividend yield is based on the fact that the Company has never paid cash dividends and does not expect to pay any cash dividends in the foreseeable future. The Company classifies stock-based compensation expense in its condensed consolidated statement of operations and comprehensive loss in the same manner in which the award recipient’s payroll costs are classified or in which the award recipient’s service payments are classified. |
Income Taxes | Income Taxes Income taxes are accounted for under the asset and liability method. Under the asset and liability method, deferred tax assets and liabilities are recognized for the future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. The effect on deferred tax assets and liabilities of a change in tax rates is recognized in income in the period that includes the enactment date. The Company records valuation allowances to reduce deferred income tax assets to the amount that is more likely than not to be realized. The Company determines whether it is more likely than not that a tax position will be sustained upon examination. If it is not more likely than not that a position will be sustained, no amount of benefit attributable to the position is recognized. The tax benefit to be recognized of any tax position that meets the more likely than not recognition threshold is calculated as the largest amount that is more than 50% likely of being realized upon resolution of the contingency. |
Segment Data | Segment Data The Company manages its operations as a single segment for the purposes of assessing performance and making operating decisions. The Company’s singular focus is on developing treatments through gene therapy and other means for patients with DMD. All of the Company’s tangible assets are held in the United States. |
Comprehensive Loss | Comprehensive Loss Comprehensive loss includes net loss, as well as other changes in stockholders’ equity that result from transactions and economic events other than those with stockholders and members. The Company’s only element of other comprehensive loss in all periods presented was unrealized gains (losses) from available-for-sale securities. |
Net Loss per Share | Net Loss per Share The Company follows the two-class method when computing net loss per share, as the Company has issued shares that meet the definition of participating securities. The two-class method determines net loss per share for each class of common and participating securities according to dividends declared or accumulated and participation rights in undistributed earnings. The two-class method requires income available to common stockholders for the period to be allocated between common and participating securities based upon their respective rights to receive dividends as if all income for the period had been distributed. Basic net loss per share attributable to common stockholders is computed by dividing the net loss attributable to common stockholders by the weighted average number of shares of common stock outstanding for the period. Diluted net loss attributable to common stockholders is computed by adjusting net loss attributable to common stockholders to reallocate undistributed earnings based on the potential impact of dilutive securities. Diluted net loss per share attributable to common stockholders is computed by dividing the diluted net loss attributable to common stockholders by the weighted average number of shares of common stock outstanding for the period, including potential dilutive shares of common stock assuming the dilutive effect of common stock equivalents. The Company’s participating securities contractually entitle the holders of such shares to participate in dividends but does not contractually require the holders of such shares to participate in losses of the Company. Accordingly, in periods in which the Company reports a net loss, such losses are not allocated to such participating securities. In periods in which the Company reports a net loss attributable to common stockholders, diluted net loss per share attributable to common stockholders is the same as basic net loss per share attributable to common stockholders, since dilutive shares of common stock are not assumed to have been issued if their effect is anti-dilutive. |
Contingencies | Contingencies Loss contingency provisions are recorded if the potential loss from any claim, asserted or unasserted, or legal proceeding is considered probable and the amount can be reasonably estimated, or a range of loss can be determined. These accruals represent the Company’s best estimate of probable loss. Disclosure also is provided when it is reasonably possible that a loss will be incurred or when it is reasonably possible that the amount of a loss will exceed the recorded provision. The Company reviews the status of each significant matter and assesses its potential financial exposure. Significant judgment is required in both the determination of probability and the determination as to whether an exposure is reasonably estimable. Because of uncertainties related to these matters, accruals are based only on the best information available at the time. As additional information becomes available, the Company reassesses the potential liability related to pending claims and may change its estimates. These changes in the estimates of the potential liabilities could have a material impact on the Company’s condensed consolidated results of operations and financial position. |
Recently Adopted Accounting Pronouncements | Recently Adopted Accounting Pronouncements The Company adopted Accounting Standards Update (“ASU”) No. 2016-02, Leases (Topic 842) |
Recently Issued Accounting Pronouncements | Recently Issued Accounting Pronouncements , Fair Value Measurement (Topic 820): Disclosure Framework - Changes to the Disclosure Requirements for Fair Value Measurement |
Summary of Significant Accoun_3
Summary of Significant Accounting Policies (Tables) | 6 Months Ended |
Jun. 30, 2019 | |
Accounting Policies [Abstract] | |
Reconciliation of Amounts From Cash Flow Statement to Balance Sheet | A reconciliation of the amounts of cash and cash equivalents and restricted cash from the cash flow statement to the balance sheet is as follows: June 30, 2019 December 31, 2018 Cash and cash equivalents as presented on balance sheet $ 51,836 $ 86,366 Restricted cash, non-current, as presented on balance sheet 327 327 Cash and cash equivalents and restricted cash as presented on cash flow statement $ 52,163 $ 86,693 |
Fair Value of Financial Asset_2
Fair Value of Financial Assets and Liabilities (Tables) | 6 Months Ended |
Jun. 30, 2019 | |
Fair Value Disclosures [Abstract] | |
Summary of Assets and Liabilities Measured at Fair Value on Recurring Basis and Indicate Level of Fair Value Hierarchy Utilized | The following tables present information about the Company’s assets and liabilities that are measured at fair value on a recurring basis and indicate the level of the fair value hierarchy utilized to determine such fair values: Fair Value Measurements as of June 30, 2019 Using: Level 1 Level 2 Level 3 Total Assets: Cash equivalents $ — $ 21,337 $ — $ 21,337 Available-for-sale securities — 15,550 — 15,550 $ — $ 36,887 $ — $ 36,887 Fair Value Measurements as of December 31, 2018 Using: Level 1 Level 2 Level 3 Total Assets: Cash equivalents $ — $ 54,423 $ — $ 54,423 Available-for-sale securities — 36,098 — 36,098 $ — $ 90,521 $ — $ 90,521 |
Available-for-Sale Securities (
Available-for-Sale Securities (Tables) | 6 Months Ended |
Jun. 30, 2019 | |
Investments Debt And Equity Securities [Abstract] | |
Schedule of Fair Value of Available-for-Sale Securities by Type of Security | As of June 30, 2019 and December 31, 2018, the fair value of available-for-sale securities by type of security was as follows: June 30, 2019 Amortized Cost Gross Unrealized Gain Gross Unrealized Loss Fair Value Investments: U.S. government agency securities $ 6,016 $ 2 $ — $ 6,018 Corporate bond securities 9,531 2 (1 ) 9,532 $ 15,547 $ 4 $ (1 ) $ 15,550 December 31, 2018 Amortized Cost Gross Unrealized Gain Gross Unrealized Loss Fair Value Investments: U.S. government agency securities $ 13,543 $ — $ (2 ) $ 13,541 Corporate bond securities 12,860 2 (5 ) 12,857 Commercial paper 9,700 — — 9,700 $ 36,103 $ 2 $ (7 ) $ 36,098 |
Summary Estimated Fair Value and Amortized Cost of Available-for-Sale Securities by Contractual Maturity | The estimated fair value and amortized cost of the Company’s available-for-sale securities by contractual maturity are summarized as follows: June 30, 2019 December 31, 2018 Amortized Cost Fair Value Amortized Cost Fair Value Due in one year or less $ 15,547 $ 15,550 $ 36,103 $ 36,098 Total available-for-sale securities $ 15,547 $ 15,550 $ 36,103 $ 36,098 |
Property and Equipment (Tables)
Property and Equipment (Tables) | 6 Months Ended |
Jun. 30, 2019 | |
Property Plant And Equipment [Abstract] | |
Summary of Property and Equipment | Property and equipment consists of the following: June 30, 2019 December 31, 2018 Furniture and fixtures $ 203 $ 187 Laboratory equipment 8,622 5,998 Leasehold improvements 4,686 4,585 Computer equipment 467 166 Computer software 356 123 Construction in process 737 1,351 15,071 12,410 Less accumulated depreciation 3,242 1,988 $ 11,829 $ 10,422 |
Prepaid Expenses and Other Cu_2
Prepaid Expenses and Other Current Assets (Tables) | 6 Months Ended |
Jun. 30, 2019 | |
Deferred Costs Capitalized Prepaid And Other Assets Disclosure [Abstract] | |
Schedule of Prepaid Expenses and Other Current Assets | Prepaid expenses and other current assets consist of the following: June 30, 2019 December 31, 2018 Prepaid research and development expenses $ 5,342 $ 4,365 Prepaid expenses and other assets 5,593 1,810 $ 10,935 $ 6,175 |
Accrued Expenses and Other Cu_2
Accrued Expenses and Other Current Liabilities (Tables) | 6 Months Ended |
Jun. 30, 2019 | |
Payables And Accruals [Abstract] | |
Summary of Accrued Expenses and Other Current Liabilities | Accrued expenses and other current liabilities consist of the following: June 30, 2019 December 31, 2018 Accrued research and development $ 4,055 $ 3,529 Accrued compensation 704 3,534 Accrued other 1,248 1,172 $ 6,007 $ 8,235 |
Equity-Based Compensation (Tabl
Equity-Based Compensation (Tables) | 6 Months Ended |
Jun. 30, 2019 | |
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract] | |
Schedule of Equity-based Compensation Expense | The Company recorded equity-based compensation expense related to all of its share-based awards to employees and non-employees in the following captions within its condensed consolidated statements of operations: Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 Research and development $ 2,114 $ 1,084 $ 3,933 $ 1,716 General and administrative 1,797 225 3,478 412 Total $ 3,911 $ 1,309 $ 7,411 $ 2,128 |
Leases (Tables)
Leases (Tables) | 6 Months Ended |
Jun. 30, 2019 | |
Leases [Abstract] | |
Future Minimum Payments for Operating and Finance Leases | As of June 30, 2019, minimum future lease payments for these operating and finance leases were as follows: Finance Leases Operating Leases 2019 $ 138 $ 1,183 2020 276 2,408 2021 276 2,444 2022 276 1,424 2023 300 686 Thereafter — 778 Total 1,266 8,923 Less: Imputed Interest 261 2,004 Total Lease Liabilities $ 1,005 $ 6,919 As of December 31, 2018, minimum future lease payments for these operating and finance leases were as follows: Finance Leases Operating Leases 2019 $ 276 $ 1,934 2020 276 2,017 2021 276 2,056 2022 485 1,023 2023 — 278 Thereafter — - Total 1,313 7,308 |
Supplemental Disclosure of Cash Flow Information Related to Leases and Weighted Average Remaining Lease Term and Discount Rate | The supplemental disclosure of cash flow information related to the Company’s leases and the weighted average remaining lease term and weighted average discount rate of the Company’s leases are as follows: For the Three Months Ended June 30, For the Six Months Ended June 30, 2019 2019 Other information Operating cash flows used for operating leases $ 318 $ 1,105 Operating lease liabilities arising from obtaining right-of-use-assets $ — $ 1,629 Finance lease liabilities arising from obtaining right-of-use assets $ — $ — Weighted-average remaining lease term (in years) Operating lease 3.9 3.9 Finance lease 3.8 3.8 Weighted-average discount rate Operating lease 12.3 % 12.3 % Finance lease 10.7 % 10.7 % |
Net Loss per Share (Tables)
Net Loss per Share (Tables) | 6 Months Ended |
Jun. 30, 2019 | |
Earnings Per Share [Abstract] | |
Schedule of Basic and Diluted Net Loss per Share Attributable to Common Stockholders | The numerator for basic and diluted net loss per share attributable to common stockholders is as follows: Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 Net loss attributable to common stockholders $ (26,525 ) $ (17,980 ) $ (56,107 ) $ (33,857 ) The denominator is as follows: Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 Weighted average shares of common stock outstanding, basic and diluted 34,843,344 34,449,758 34,810,101 31,916,295 Net loss per share attributable to common stockholders, basic and diluted is as follows: Three Months Ended June 30, Six Months Ended June 30, 2019 2018 2019 2018 Net loss per share attributable to common stockholders $ (0.76 ) $ (0.52 ) $ (1.61 ) $ (1.06 ) |
Schedule of Antidilutive Securities Excluded from Calculation of Diluted Net Loss per Share Attributable to Common Stockholders | The following potential common stock equivalents, presented based on amounts outstanding at each period end, were excluded from the calculation of diluted net loss per share attributable to common stockholders for the periods indicated because including them would have had an anti-dilutive effect for the three and six months ended June 30: 2019 2018 Options to purchase shares of common stock 2,730,362 752,773 Unvested shares of common stock 523,687 951,066 3,254,049 1,703,839 |
Nature of the Business and Ba_2
Nature of the Business and Basis of Presentation - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands | Jul. 30, 2019 | Jun. 30, 2019 | Jun. 30, 2018 | Jun. 30, 2019 | Jun. 30, 2018 | Dec. 31, 2018 | Jan. 25, 2018 |
Nature Of Business And Basis Of Presentation [Line Items] | |||||||
Net loss | $ 26,525 | $ 17,980 | $ 56,107 | $ 33,857 | |||
Accumulated deficit | 255,163 | 255,163 | $ 199,056 | ||||
Net cash used in operating activities | 52,228 | $ 33,503 | |||||
Cash, cash equivalents and available-for-sale securities | $ 67,386 | $ 67,386 | |||||
Subsequent Event [Member] | |||||||
Nature Of Business And Basis Of Presentation [Line Items] | |||||||
Gross proceeds from private placement | $ 60,000 | ||||||
Net proceeds from private placement | 58,200 | ||||||
Private Placement [Member] | Subsequent Event [Member] | |||||||
Nature Of Business And Basis Of Presentation [Line Items] | |||||||
Placement agent fees | $ 1,800 | ||||||
Common Stock [Member] | Private Placement [Member] | Subsequent Event [Member] | |||||||
Nature Of Business And Basis Of Presentation [Line Items] | |||||||
Stock issued and sold | 10,607,525 | ||||||
Stock price per share | $ 4.65 | ||||||
Pre-Funded Warrants [Member] | Private Placement [Member] | Subsequent Event [Member] | |||||||
Nature Of Business And Basis Of Presentation [Line Items] | |||||||
Warrants to purchase common stock | 2,295,699 | ||||||
Warrants price per share | $ 4.64 | ||||||
Warrants exercisable for common stock | 1 | ||||||
Exercise price of warrant | $ 0.01 | ||||||
Corporate Conversion [Member] | |||||||
Nature Of Business And Basis Of Presentation [Line Items] | |||||||
Common stock, conversion ratio | 84.85% |
Summary of Significant Accoun_4
Summary of Significant Accounting Policies - Additional Information (Detail) - USD ($) | 3 Months Ended | 6 Months Ended | ||||
Jun. 30, 2019 | Jun. 30, 2018 | Jun. 30, 2019 | Jun. 30, 2018 | Jan. 01, 2019 | Dec. 31, 2018 | |
Significant Accounting Policies [Line Items] | ||||||
Restricted cash deposit | $ 327,000 | $ 327,000 | $ 327,000 | |||
Restricted cash noncurrent | 327,000 | 327,000 | $ 327,000 | |||
Income tax expense (benefit) | 0 | $ 0 | 0 | $ 0 | ||
Operating lease, right-of-use asset | 5,618,000 | 5,618,000 | $ 4,600,000 | |||
Operating lease liability | $ 6,919,000 | $ 6,919,000 | $ 5,900,000 | |||
2018 Omnibus Incentive Plan [Member] | ||||||
Significant Accounting Policies [Line Items] | ||||||
Number of shares authorized for common stock for equity awards | 5,001,000 | 5,001,000 |
Summary of Significant Accoun_5
Summary of Significant Accounting Policies - Reconciliation of Amounts From Cash Flow Statement to Balance Sheet (Detail) - USD ($) $ in Thousands | Jun. 30, 2019 | Dec. 31, 2018 | Jun. 30, 2018 | Dec. 31, 2017 |
Reconciliation Of Beginning And End Of Period Amounts From Cash Flow Statement To Balance Sheet [Abstract] | ||||
Cash and cash equivalents as presented on balance sheet | $ 51,836 | $ 86,366 | ||
Restricted cash, non-current, as presented on balance sheet | 327 | 327 | ||
Cash and cash equivalents and restricted cash as presented on cash flow statement | $ 52,163 | $ 86,693 | $ 146,061 | $ 52,145 |
Fair Value of Financial Asset_3
Fair Value of Financial Assets and Liabilities - Summary of Assets and Liabilities Measured at Fair Value on Recurring Basis and Indicate Level of Fair Value Hierarchy Utilized (Detail) - USD ($) $ in Thousands | Jun. 30, 2019 | Dec. 31, 2018 |
Assets: | ||
Cash equivalents | $ 21,337 | $ 54,423 |
Available-for-sale securities | 15,550 | 36,098 |
Assets Fair Value Disclosure | 36,887 | 90,521 |
Level 2 [Member] | ||
Assets: | ||
Cash equivalents | 21,337 | 54,423 |
Available-for-sale securities | 15,550 | 36,098 |
Assets Fair Value Disclosure | $ 36,887 | $ 90,521 |
Fair Value of Financial Asset_4
Fair Value of Financial Assets and Liabilities - Additional Information (Detail) - USD ($) | 6 Months Ended | 12 Months Ended |
Jun. 30, 2019 | Dec. 31, 2018 | |
Fair Value Disclosures [Abstract] | ||
Fair value, assets, level 1 to level 2 transfers, amount | $ 0 | $ 0 |
Fair value, assets, level 2 to level 1 transfers, amount | 0 | 0 |
Fair value, assets, transfers into level 3, amount | 0 | 0 |
Fair value, assets, transfers out of level 3, amount | $ 0 | $ 0 |
Available-for-Sale Securities -
Available-for-Sale Securities - Schedule of Fair Value of Available-for-Sale Securities by Type of Security (Detail) - USD ($) $ in Thousands | Jun. 30, 2019 | Dec. 31, 2018 |
Debt Securities, Available-for-sale [Line Items] | ||
Amortized Cost | $ 15,547 | $ 36,103 |
Gross Unrealized Gain | 4 | 2 |
Gross Unrealized Loss | (1) | (7) |
Fair Value | 15,550 | 36,098 |
U.S. Government Agency Securities [Member] | ||
Debt Securities, Available-for-sale [Line Items] | ||
Amortized Cost | 6,016 | 13,543 |
Gross Unrealized Gain | 2 | 0 |
Gross Unrealized Loss | (2) | |
Fair Value | 6,018 | 13,541 |
Corporate Bond Securities [Member] | ||
Debt Securities, Available-for-sale [Line Items] | ||
Amortized Cost | 9,531 | 12,860 |
Gross Unrealized Gain | 2 | 2 |
Gross Unrealized Loss | (1) | (5) |
Fair Value | $ 9,532 | 12,857 |
Commercial Paper [Member] | ||
Debt Securities, Available-for-sale [Line Items] | ||
Amortized Cost | 9,700 | |
Gross Unrealized Gain | 0 | |
Fair Value | $ 9,700 |
Available-for-Sale Securities_2
Available-for-Sale Securities - Summary Estimated Fair Value and Amortized Cost of Available-for-Sale Securities by Contractual Maturity (Detail) - USD ($) $ in Thousands | Jun. 30, 2019 | Dec. 31, 2018 |
Investments Debt And Equity Securities [Abstract] | ||
Due in one year or less, amortized cost | $ 15,547 | $ 36,103 |
Total available-for-sale securities, amortized cost | 15,547 | 36,103 |
Due in one year or less, fair value | 15,550 | 36,098 |
Total available-for-sale securities, fair value | $ 15,550 | $ 36,098 |
Available-for-Sale Securities_3
Available-for-Sale Securities - Additional Information (Detail) | 6 Months Ended | 12 Months Ended |
Jun. 30, 2019 | Dec. 31, 2018 | |
Investments Debt And Equity Securities [Abstract] | ||
Available-for-sale securities weighted average maturity period | 2 months 12 days | 3 months 18 days |
Property and Equipment - Summar
Property and Equipment - Summary of Property and Equipment (Detail) - USD ($) $ in Thousands | Jun. 30, 2019 | Dec. 31, 2018 |
Property, Plant and Equipment [Line Items] | ||
Property and equipment, gross | $ 15,071 | $ 12,410 |
Less accumulated depreciation | 3,242 | 1,988 |
Property and equipment, net | 11,829 | 10,422 |
Furniture and Fixtures [Member] | ||
Property, Plant and Equipment [Line Items] | ||
Property and equipment, gross | 203 | 187 |
Laboratory Equipment [Member] | ||
Property, Plant and Equipment [Line Items] | ||
Property and equipment, gross | 8,622 | 5,998 |
Leasehold Improvements [Member] | ||
Property, Plant and Equipment [Line Items] | ||
Property and equipment, gross | 4,686 | 4,585 |
Computer Equipment [Member] | ||
Property, Plant and Equipment [Line Items] | ||
Property and equipment, gross | 467 | 166 |
Computer Software [Member] | ||
Property, Plant and Equipment [Line Items] | ||
Property and equipment, gross | 356 | 123 |
Construction in Progress [Member] | ||
Property, Plant and Equipment [Line Items] | ||
Property and equipment, gross | $ 737 | $ 1,351 |
Property and Equipment - Additi
Property and Equipment - Additional Information (Detail) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended | ||
Jun. 30, 2019 | Jun. 30, 2018 | Jun. 30, 2019 | Jun. 30, 2018 | |
Property Plant And Equipment [Abstract] | ||||
Depreciation expense | $ 658 | $ 313 | $ 1,254 | $ 540 |
Prepaid Expenses and Other Cu_3
Prepaid Expenses and Other Current Assets - Schedule of Prepaid Expenses and Other Current Assets (Details) - USD ($) $ in Thousands | Jun. 30, 2019 | Dec. 31, 2018 |
Deferred Costs Capitalized Prepaid And Other Assets Disclosure [Abstract] | ||
Prepaid research and development expenses | $ 5,342 | $ 4,365 |
Prepaid expenses and other assets | 5,593 | 1,810 |
Prepaid expenses and other current assets | $ 10,935 | $ 6,175 |
Accrued Expenses and Other Cu_3
Accrued Expenses and Other Current Liabilities - Summary of Accrued Expenses and Other Current Liabilities (Detail) - USD ($) $ in Thousands | Jun. 30, 2019 | Dec. 31, 2018 |
Accrued Expenses And Other Current Liabilities [Line Items] | ||
Accrued expenses and other current liabilities | $ 6,007 | $ 8,235 |
Accrued Research and Development [Member] | ||
Accrued Expenses And Other Current Liabilities [Line Items] | ||
Accrued expenses and other current liabilities | 4,055 | 3,529 |
Accrued Compensation [Member] | ||
Accrued Expenses And Other Current Liabilities [Line Items] | ||
Accrued expenses and other current liabilities | 704 | 3,534 |
Accrued Other [Member] | ||
Accrued Expenses And Other Current Liabilities [Line Items] | ||
Accrued expenses and other current liabilities | $ 1,248 | $ 1,172 |
Equity-Based Compensation - Add
Equity-Based Compensation - Additional Information (Detail) - 2018 Omnibus Incentive Plan [Member] | 3 Months Ended | 6 Months Ended |
Jun. 30, 2019shares | Jun. 30, 2019shares | |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | ||
Number of shares authorized for common stock for equity awards | 5,001,000 | 5,001,000 |
Common stock purchased | 101,000 | 1,644,421 |
Equity-Based Compensation - Sch
Equity-Based Compensation - Schedule of Equity-based Compensation Expense (Detail) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended | ||
Jun. 30, 2019 | Jun. 30, 2018 | Jun. 30, 2019 | Jun. 30, 2018 | |
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items] | ||||
Stock-based compensation expense | $ 3,911 | $ 1,309 | $ 7,411 | $ 2,128 |
Research and Development [Member] | ||||
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items] | ||||
Stock-based compensation expense | 2,114 | 1,084 | 3,933 | 1,716 |
General and Administrative [Member] | ||||
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items] | ||||
Stock-based compensation expense | $ 1,797 | $ 225 | $ 3,478 | $ 412 |
Income Taxes - Additional Infor
Income Taxes - Additional Information (Detail) - USD ($) | 3 Months Ended | 6 Months Ended | |||
Jun. 30, 2019 | Jun. 30, 2018 | Jun. 30, 2019 | Jun. 30, 2018 | Dec. 31, 2018 | |
Income Tax Disclosure [Abstract] | |||||
Income tax expense (benefit) | $ 0 | $ 0 | $ 0 | $ 0 | |
Unrecognized tax benefits | $ 0 | $ 0 | $ 0 |
Leases - Additional Information
Leases - Additional Information (Detail) $ in Thousands | 1 Months Ended | 3 Months Ended | 6 Months Ended | |||
Jan. 31, 2019USD ($)ft² | Jan. 31, 2018USD ($)ft² | Jun. 30, 2019USD ($) | Jun. 30, 2019USD ($) | Dec. 31, 2018USD ($) | Nov. 30, 2018USD ($) | |
Commitment And Contingencies [Line Items] | ||||||
Remaining lease terms | 3 years 10 months 24 days | 3 years 10 months 24 days | ||||
Future minimum rent commitment | $ 8,923 | $ 8,923 | $ 7,308 | |||
Future minimum lease commitment | 1,266 | 1,266 | $ 1,313 | |||
Lease expense | $ 602 | $ 1,124 | ||||
Cambridge, Massachusetts [Member] | Lab Equipment [Member] | ||||||
Commitment And Contingencies [Line Items] | ||||||
Lease term of contract | 48 months | |||||
Future minimum lease commitment | $ 1,266 | |||||
Lab Space [Member] | Cambridge, Massachusetts [Member] | ||||||
Commitment And Contingencies [Line Items] | ||||||
Area of lease agreement | ft² | 9,500 | |||||
Lease term | 5 years | |||||
Lessee, Operating Lease, Existence of Option to Extend [true false] | true | |||||
Lease renewal term | 2 years | |||||
Future minimum rent commitment | $ 3,000 | |||||
Office Space [Member] | Cambridge, Massachusetts [Member] | ||||||
Commitment And Contingencies [Line Items] | ||||||
Area of lease agreement | ft² | 5,000 | 16,000 | ||||
Future minimum rent commitment | $ 2,500 | $ 3,400 | ||||
Lease expiration period | 2025-01 | 2022-02 | ||||
Minimum [Member] | ||||||
Commitment And Contingencies [Line Items] | ||||||
Remaining lease terms | 1 year | 1 year | ||||
Maximum [Member] | ||||||
Commitment And Contingencies [Line Items] | ||||||
Remaining lease terms | 6 years | 6 years |
Leases - Future Minimum Payment
Leases - Future Minimum Payments for Operating and Finance Leases (Detail) - USD ($) $ in Thousands | Jun. 30, 2019 | Jan. 01, 2019 | Dec. 31, 2018 |
Finance Leases | |||
2019 | $ 138 | $ 276 | |
2020 | 276 | 276 | |
2021 | 276 | 276 | |
2022 | 276 | 485 | |
2023 | 300 | ||
Total future minimum lease payments | 1,266 | 1,313 | |
Less: Imputed Interest | 261 | ||
Total Lease Liabilities | 1,005 | ||
Operating Leases | |||
2019 | 1,183 | 1,934 | |
2020 | 2,408 | 2,017 | |
2021 | 2,444 | 2,056 | |
2022 | 1,424 | 1,023 | |
2023 | 686 | 278 | |
Thereafter | 778 | ||
Total future minimum lease payments | 8,923 | $ 7,308 | |
Less: Imputed Interest | 2,004 | ||
Operating lease liability | $ 6,919 | $ 5,900 |
Leases - Supplemental Disclosur
Leases - Supplemental Disclosure of Cash Flow Information Related to Leases (Detail) $ in Thousands | 3 Months Ended | 6 Months Ended |
Jun. 30, 2019USD ($) | Jun. 30, 2019USD ($) | |
Other information | ||
Operating cash flows used for operating leases | $ 318 | $ 1,105 |
Operating lease liabilities arising from obtaining right-of-use asset | $ 1,629 | |
Weighted-average remaining lease term (in years) | ||
Operating lease | 3 years 10 months 24 days | 3 years 10 months 24 days |
Finance lease | 3 years 9 months 18 days | 3 years 9 months 18 days |
Weighted-average discount rate | ||
Operating lease | 12.30% | 12.30% |
Finance lease | 10.70% | 10.70% |
Net Loss per Share - Schedule o
Net Loss per Share - Schedule of Basic and Diluted Net Loss per Share Attributable to Common Stockholders (Detail) - USD ($) $ / shares in Units, $ in Thousands | 3 Months Ended | 6 Months Ended | ||
Jun. 30, 2019 | Jun. 30, 2018 | Jun. 30, 2019 | Jun. 30, 2018 | |
Earnings Per Share [Abstract] | ||||
Net loss attributable to common stockholders | $ (26,525) | $ (17,980) | $ (56,107) | $ (33,857) |
Weighted average shares of common stock outstanding, basic and diluted | 34,843,344 | 34,449,758 | 34,810,101 | 31,916,295 |
Net loss per share attributable to common stockholders | $ (0.76) | $ (0.52) | $ (1.61) | $ (1.06) |
Net Loss per Share - Schedule_2
Net Loss per Share - Schedule of Antidilutive Securities Excluded from Calculation of Diluted Net Loss per Share Attributable to Common Stockholders (Detail) - shares | 6 Months Ended | |
Jun. 30, 2019 | Jun. 30, 2018 | |
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items] | ||
Common stock equivalents excluded from calculation of diluted net loss per share | 3,254,049 | 1,703,839 |
Options to Purchase Shares of Common Stock [Member] | ||
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items] | ||
Common stock equivalents excluded from calculation of diluted net loss per share | 2,730,362 | 752,773 |
Unvested Shares of Common Stock [Member] | ||
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items] | ||
Common stock equivalents excluded from calculation of diluted net loss per share | 523,687 | 951,066 |
Subsequent Events - Additional
Subsequent Events - Additional Information (Detail) - Subsequent Event [Member] $ / shares in Units, $ in Thousands | Jul. 30, 2019USD ($)$ / sharesshares |
Subsequent Event [Line Items] | |
Gross proceeds from private placement | $ | $ 60,000 |
Private Placement [Member] | |
Subsequent Event [Line Items] | |
Placement agent fees | $ | $ 1,800 |
Private Placement [Member] | Common Stock [Member] | |
Subsequent Event [Line Items] | |
Stock issued and sold | shares | 10,607,525 |
Stock price per share | $ / shares | $ 4.65 |
Private Placement [Member] | Pre-Funded Warrants [Member] | |
Subsequent Event [Line Items] | |
Warrants to purchase common stock | shares | 2,295,699 |
Warrants price per share | $ / shares | $ 4.64 |
Warrants exercisable for common stock | shares | 1 |
Exercise price of warrant | $ / shares | $ 0.01 |