Document and Entity Information
Document and Entity Information - shares | 6 Months Ended | |
Jun. 30, 2018 | Aug. 03, 2018 | |
Document And Entity Information [Abstract] | ||
Document Type | 10-Q | |
Amendment Flag | false | |
Document Period End Date | Jun. 30, 2018 | |
Document Fiscal Year Focus | 2,018 | |
Document Fiscal Period Focus | Q2 | |
Trading Symbol | CPRX | |
Entity Registrant Name | CATALYST PHARMACEUTICALS, INC. | |
Entity Central Index Key | 1,369,568 | |
Current Fiscal Year End Date | --12-31 | |
Entity Filer Category | Accelerated Filer | |
Entity Common Stock, Shares Outstanding | 102,599,258 |
Consolidated Balance Sheets
Consolidated Balance Sheets - USD ($) | Jun. 30, 2018 | Dec. 31, 2017 |
Current Assets: | ||
Cash and cash equivalents | $ 9,887,939 | $ 57,496,702 |
Short-term investments | 58,520,956 | 26,516,711 |
Prepaid expenses and other current assets | 677,341 | 1,173,744 |
Total current assets | 69,086,236 | 85,187,157 |
Investments | 5,005,321 | |
Property and equipment, net | 187,131 | 191,385 |
Deposits | 8,888 | 8,888 |
Total assets | 74,287,576 | 85,387,430 |
Current Liabilities: | ||
Accounts payable | 922,593 | 1,945,575 |
Accrued expenses and other liabilities | 2,159,435 | 2,320,587 |
Total current liabilities | 3,082,028 | 4,266,162 |
Accrued expenses and other liabilities, non-current | 143,335 | 157,456 |
Total liabilities | 3,225,363 | 4,423,618 |
Commitments and contingencies | ||
Stockholders' equity: | ||
Preferred stock, $0.001 par value, 5,000,000 shares authorized: none issued and outstanding at June 30, 2018 and December 31, 2017 | ||
Common stock, $0.001 par value, 150,000,000 shares authorized; 102,599,258 shares and 102,549,498 shares issued and outstanding at June 30, 2018 and December 31, 2017, respectively | 102,599 | 102,549 |
Additional paid-in capital | 209,221,591 | 207,421,710 |
Accumulated deficit | (138,225,479) | (126,560,447) |
Accumulated other comprehensive loss | (36,498) | |
Total stockholders' equity | 71,062,213 | 80,963,812 |
Total liabilities and stockholders' equity | $ 74,287,576 | $ 85,387,430 |
Consolidated Balance Sheets (Pa
Consolidated Balance Sheets (Parenthetical) - $ / shares | Jun. 30, 2018 | Dec. 31, 2017 |
Statement of Financial Position [Abstract] | ||
Preferred stock, par value | $ 0.001 | $ 0.001 |
Preferred stock, shares authorized | 5,000,000 | 5,000,000 |
Preferred stock, shares issued | 0 | 0 |
Preferred stock, shares outstanding | 0 | 0 |
Common stock, par value | $ 0.001 | $ 0.001 |
Common stock, shares authorized | 150,000,000 | 150,000,000 |
Common stock, shares issued | 102,599,258 | 102,549,498 |
Common stock, shares outstanding | 102,599,258 | 102,549,498 |
Consolidated Statements of Oper
Consolidated Statements of Operations and Comprehensive Loss (unaudited) - USD ($) | 3 Months Ended | 6 Months Ended | ||
Jun. 30, 2018 | Jun. 30, 2017 | Jun. 30, 2018 | Jun. 30, 2017 | |
Operating costs and expenses: | ||||
Research and development | $ 3,704,824 | $ 2,451,751 | $ 6,963,866 | $ 5,265,680 |
General and administrative | 2,631,031 | 1,729,520 | 5,305,429 | 3,595,462 |
Total operating costs and expenses | 6,335,855 | 4,181,271 | 12,269,295 | 8,861,142 |
Loss from operations | (6,335,855) | (4,181,271) | (12,269,295) | (8,861,142) |
Other income, net | 370,715 | 91,039 | 604,263 | 201,016 |
Change in fair value of warrants liability | 210,331 | (186,904) | ||
Loss before income taxes | (5,965,140) | (3,879,901) | (11,665,032) | (8,847,030) |
Provision for income taxes | 0 | 0 | 0 | 0 |
Net loss | $ (5,965,140) | $ (3,879,901) | $ (11,665,032) | $ (8,847,030) |
Net loss per share - basic and diluted | $ (0.06) | $ (0.05) | $ (0.11) | $ (0.11) |
Weighted average shares outstanding - basic and diluted | 102,596,446 | 83,905,827 | 102,577,005 | 83,441,650 |
Net loss | $ (5,965,140) | $ (3,879,901) | $ (11,665,032) | $ (8,847,030) |
Other comprehensive loss: | ||||
Unrealized gain (loss) on available-for-sale securities | (14,672) | (36,498) | ||
Comprehensive loss | $ (5,979,812) | $ (3,879,901) | $ (11,701,530) | $ (8,847,030) |
Consolidated Statement of Stock
Consolidated Statement of Stockholders' Equity (unaudited) - 6 months ended Jun. 30, 2018 - USD ($) | Total | Common Stock [Member] | Additional Paid-in Capital [Member] | Accumulated Deficit [Member] | Accumulated Other Comprehensive Loss [Member] |
Beginning Balance at Dec. 31, 2017 | $ 80,963,812 | $ 102,549 | $ 207,421,710 | $ (126,560,447) | |
Issuance of common stock, net | 10,549 | 3 | 10,546 | ||
Issuance of stock options for services | 1,747,850 | 1,747,850 | |||
Exercise of stock options for common stock | 41,532 | 47 | 41,485 | ||
Other comprehensive loss | (36,498) | $ (36,498) | |||
Net loss | (11,665,032) | (11,665,032) | |||
Ending Balance at Jun. 30, 2018 | $ 71,062,213 | $ 102,599 | $ 209,221,591 | $ (138,225,479) | $ (36,498) |
Consolidated Statements of Cash
Consolidated Statements of Cash Flows (unaudited) - USD ($) | 6 Months Ended | |
Jun. 30, 2018 | Jun. 30, 2017 | |
Operating Activities: | ||
Net loss | $ (11,665,032) | $ (8,847,030) |
Adjustments to reconcile net loss to net cash used in operating activities: | ||
Depreciation | 16,191 | 25,915 |
Stock-based compensation | 1,762,847 | 1,392,713 |
Change in fair value of warrants liability | 186,904 | |
(Increase) decrease in: | ||
Prepaid expenses and other current assets and deposits | 496,403 | 426,386 |
Increase (decrease) in: | ||
Accounts payable | (1,022,982) | (240,831) |
Accrued expenses and other liabilities | (175,273) | (23,921) |
Net cash used in operating activities | (10,587,846) | (7,079,864) |
Investing Activities: | ||
Purchases of property and equipment | (11,937) | |
Purchases of investments | (37,046,064) | (34,910) |
Net cash provided by (used in) investing activities | (37,058,001) | (34,910) |
Financing Activities: | ||
Payment of employee withholding tax related to stock-based compensation | (4,448) | |
Proceeds from exercise of warrants | 1,805,437 | |
Proceeds from exercise of stock options | 41,532 | |
Net cash provided by (used in) financing activities | 37,084 | 1,805,437 |
Net increase (decrease) in cash and cash equivalents | (47,608,763) | (5,309,337) |
Cash and cash equivalents - beginning of period | 57,496,702 | 13,893,064 |
Cash and cash equivalents - end of period | 9,887,939 | 8,583,727 |
Non-cash investing and financing activities: | ||
Unrealized gain (loss) on available-for-sale securities | $ (36,498) | |
Exercise of liability classified warrants for common stock | $ 309,130 |
Organization and Description of
Organization and Description of Business | 6 Months Ended |
Jun. 30, 2018 | |
Organization, Consolidation and Presentation of Financial Statements [Abstract] | |
Organization and Description of Business | 1. Organization and Description of Business. Catalyst Pharmaceuticals, Inc. (the Company) is a development-stage biopharmaceutical company focused on developing and commercializing innovating therapies for people with rare debilitating, chronic neuromuscular and neurological diseases, including Lambert-Eaton Myasthenic Syndrome (LEMS), Congenital Myasthenic Syndromes (CMS), MuSK antibody positive myasthenia gravis (MuSK-MG), Since inception, the Company has devoted substantially all of its efforts to business planning, research and development, recruiting management and technical staff, acquiring operating assets and raising capital. The Company’s primary focus is on the development and commercialization of its drug candidates. The Company has incurred operating losses in each period from inception through June 30, 2018. The Company has been able to fund its cash needs to date through several public and private offerings of its common stock and warrants, through government grants, and through an investment by a strategic purchaser. See Note 10. Capital Resources While there can be no assurance, based on currently available information, the Company estimates that it has sufficient resources to support its operations for at least the next 12 months. The Company may raise additional funds in the future, if required for its business, through public or private equity offerings, debt financings, corporate collaborations, governmental research grants or other means. The Company may also seek to raise new capital to fund additional product development efforts, even if it has sufficient funds for its planned operations. Any sale by the Company of additional equity or convertible debt securities could result in dilution to the Company’s current stockholders. There can be no assurance that any required additional funding will be available to the Company at all or available on terms acceptable to the Company. Further, to the extent that the Company raises additional funds through collaborative arrangements, it may be necessary to relinquish some rights to the Company’s drug candidates or grant sublicenses on terms that are not favorable to the Company. If the Company is not able to secure additional funding when needed, the Company may have to delay, reduce the scope of, or eliminate one or more research and development programs, which could have an adverse effect on the Company’s business. |
Basis of Presentation and Signi
Basis of Presentation and Significant Accounting Policies | 6 Months Ended |
Jun. 30, 2018 | |
Accounting Policies [Abstract] | |
Basis of Presentation and Significant Accounting Policies | 2. Basis of Presentation and Significant Accounting Policies. a. INTERIM FINANCIAL STATEMENTS. 10-Q In the opinion of management, the accompanying unaudited interim consolidated financial statements of the Company contain all adjustments (consisting of only normal recurring adjustments) necessary to present fairly the financial position of the Company as of the dates and for the periods presented. Accordingly, these consolidated statements should be read in conjunction with the financial statements and notes thereto for the year ended December 31, 2017 included in the 2017 Annual Report on Form 10-K b. PRINCIPLES OF CONSOLIDATION c. USE OF ESTIMATES. d. CASH AND CASH EQUIVALENTS. e. INVESTMENTS Short-term bond fund The short-term bond fund is classified in trading securities. Trading securities are recorded at fair value based on the closing market price of the security. For trading securities, the Company recognizes realized gains and losses and unrealized gains and losses to earnings. At June 30, 2018 and December 31, 2017, the only investment classified as trading securities was the short-term bond fund. Unrealized gain (loss) on trading securities was $29,431 and ($29,430), respectively, for the three and six months ended June 30, 2018, and $0 and $29,430 for the three and six months ended June 30, 2017 and is included in other income, net in the accompanying consolidated statements of operations. U.S. Treasuries U.S. Treasuries are classified as available-for-sale available-for-sale Available-for-sale non-current available-for-sale available-for-sale available-for-sale f. PREPAID EXPENSES AND OTHER CURRENT ASSETS pre-commercialization pre-clinical g. FAIR VALUE OF FINANCIAL INSTRUMENTS. h. FAIR VALUE MEASUREMENTS. Level 1 inputs utilize quoted prices (unadjusted) in active markets for identical assets or liabilities that the Company has the ability to access at the measurement date. Level 2 inputs are inputs other than quoted prices included in Level 1 that are observable for the asset or liability, either directly or indirectly. Level 2 inputs may include quoted prices for similar assets and liabilities in active markets, as well as inputs that are observable for the asset or liability (other than quoted prices), such as interest rates, foreign exchange rates, and yield curves that are observable at commonly quoted intervals. Level 3 inputs are unobservable inputs for the asset or liability, which are typically based on an entity’s own assumptions, as there is little, if any, related market activity. In instances where the determination of the fair value measurement is based on inputs from different levels of the fair value hierarchy, the level in the fair value hierarchy within which the entire fair value measurement falls is based on the lowest level input that is significant to the fair value measurement in its entirety. The Company’s assessment of the significance of a particular input to the fair value measurement in its entirety requires judgment, and considers factors specific to the asset or liability. Fair Value Measurements at Reporting Date Using Balances as of Quoted Prices in Significant Significant Cash and cash equivalents: Money market funds $ 9,496,648 $ 9,496,648 $ — $ — Short-term investments: Short-term bond fund $ 26,530,474 $ 26,530,474 $ — $ — U.S. Treasuries $ 31,990,482 $ — $ 31,990,482 $ — Investments: U.S. Treasuries $ 5,005,321 $ — $ 5,005,321 $ — Balances as of Quoted Prices in Significant Significant Cash and cash equivalents: Money market funds $ 56,820,688 $ 56,820,688 $ — $ — Short-term investments: Short-term bond fund $ 26,516,711 $ 26,516,711 $ — $ — i. WARRANTS LIABILITY. j. STOCK-BASED COMPENSATION. As of June 30, 2018, there were outstanding stock options to purchase 7,719,166 shares of common stock, of which stock options to purchase 4,096,662 shares of common stock were exercisable as of June 30, 2018. For the three and six-month Three months ended June 30, Six months ended June 30, 2018 2017 2018 2017 Research and development $ 285,625 $ 223,552 $ 579,940 $ 429,904 General and administrative 505,882 415,017 1,182,907 962,809 Total stock-based compensation $ 791,507 $ 638,569 $ 1,762,847 $ 1,392,713 k. COMPREHENSIVE INCOME (LOSS). available-for-sale l. NET LOSS PER SHARE. June 30, 2018 2017 Options to purchase common stock 7,719,166 6,090,000 Warrants to purchase common stock — 675,000 Unvested restricted stock — 26,667 Potential equivalent common stock excluded 7,719,166 6,791,667 Potentially dilutive options to purchase common stock as of June 30, 2018 have exercise prices ranging from $0.79 to $4.64. Potentially dilutive options to purchase common stock as of June 30, 2017 had exercise prices ranging from $0.47 to $4.64. Potentially dilutive warrants to purchase common stock as of June 30, 2017 had an exercise price of $2.08 and expired in August 2017. m. RECENTLY ISSUED ACCOUNTING STANDARDS . No. 2016-02, Leases (Topic 842) 2016-02 In May 2017, the FASB issued ASU No. 2017-09, Compensation – Stock Compensation (Topic 718): Scope of Modification Accounting 2017-09 In June 2018, the FASB issued ASU No. 2018-07, Compensation - Stock Compensation (Topic 718): Improvements to Nonemployee Share-Based Payment Accounting 2018-07 n. RECLASSIFICATIONS. |
Warrants Liability, at Fair Val
Warrants Liability, at Fair Value | 6 Months Ended |
Jun. 30, 2018 | |
Text Block [Abstract] | |
Warrants Liability, at Fair Value | 3. Warrants Liability, at Fair Value. 2011 Warrants The Company allocated approximately $1.3 million of proceeds from its October 2011 registered direct offering to the fair value of common stock purchase warrants issued in connection with the offering that were classified as a liability (the 2011 warrants). The 2011 warrants were classified as a liability because of provisions in such warrants that allowed for the net cash settlement of such warrants in the event of certain fundamental transactions (as defined in the warrant agreement). During the period that the 2011 warrants were outstanding, the valuation of the 2011 warrants was determined using the Black-Scholes Model. This model uses inputs such as the underlying price of the shares issued when the warrant is exercised, volatility, risk free interest rate and expected life of the instrument. The Company had determined that the 2011 warrants liability should be classified within Level 3 of the fair value hierarchy by evaluating each input for the Black-Scholes Model against the fair value hierarchy criteria and using the lowest level of input as the basis for the fair value classification. There are six inputs: closing price of the Company’s common stock on the day of evaluation; the exercise price of the warrants; the remaining term of the warrants; the volatility of the Company’s common stock; annual rate of dividends; and the risk-free rate of return. Of those inputs, the exercise price of the warrants and the remaining term were readily observable in the warrants agreement. The annual rate of dividends was based on the Company’s historical practice of not granting dividends. The closing price of the Company’s common stock would fall under Level 1 of the fair value hierarchy as it is a quoted price in an active market. The risk-free rate of return was a Level 2 input, while the historical volatility was a Level 3 input in accordance with the fair value accounting guidance. Since the lowest level input was a Level 3, the Company determined the 2011 warrants liability were most appropriately classified within Level 3 of the fair value hierarchy. This liability was subject to a fair value mark-to-market The following table rolls forward the fair value of the Company’s warrants liability activity for the three and six-month Three months ended Six months ended June 30, 2017 June 30, 2017 Fair value, beginning of period $ 519,461 $ 122,226 Issuance of warrants — — Exercise of warrants (309,130 ) (309,130 ) Change in fair value (210,331 ) 186,904 Fair value, end of period $ — $ — On May 2, 2017, the outstanding and unexercised 2011 warrants expired. During both the three and six months ended June 30, 2017, 613,913 of the 2011 warrants were exercised, with proceeds of $798,087 to the Company. |
Investments
Investments | 6 Months Ended |
Jun. 30, 2018 | |
Investments, Debt and Equity Securities [Abstract] | |
Investments | 4. Investments. Available-for-sale investments by security type were as follows: Amortized Gross Gross Estimated At June 30, 2018: U.S. Treasuries - ST $ 32,007,257 $ — $ (16,775 ) $ 31,990,482 U.S. Treasuries - LT 5,025,044 — (19,723 ) 5,005,321 Total $ 37,032,301 $ — $ (36,498 ) $ 36,995,803 At December 31, 2017, the Company did not have any available-for-sale securities. In accordance with FASB ASC Topic 320, “Investments – Debt and Equity Securities”, or ASC 320, the Company has classified its U.S. Treasuries as available-for-sale available-for-sale Certain U.S. Treasuries at June 30, 2018 had fair values less than their amortized costs and, therefore, contained unrealized losses. Given that the Company has no intent to sell the U.S. Treasuries until a recovery of its fair value, which may be at maturity, and there are no current requirements to sell any of these securities, the Company did not consider these investments to be other-than-temporarily impaired as of June 30, 2018. The Company anticipates full recovery of amortized costs with respect to these investments at maturity. The duration of time the U.S. Treasuries have been in a continuous unrealized loss position as of June 30, 2018 was less than 6 months. The estimated fair values of available-for-sale securities at June 30, 2018, by contractual maturity, are summarized as follows: June 30, 2018 Due in one year or less $ 31,990,482 Due after one year but within two years 5,005,321 $ 36,995,803 |
Prepaid Expenses and Other Curr
Prepaid Expenses and Other Current Assets | 6 Months Ended |
Jun. 30, 2018 | |
Text Block [Abstract] | |
Prepaid Expenses and Other Current Assets | 5. Prepaid Expenses and Other Current Assets. Prepaid expenses and other current assets consist of the following: June 30, 2018 December 31, 2017 Prepaid research fees $ 211,124 $ 388,977 Prepaid insurance 306,689 638,139 Prepaid pre-commercialization 8,925 65,000 Prepaid subscription fees 69,068 23,347 Prepaid rent 20,828 — Other 60,707 58,281 Total prepaid expenses and other current assets $ 677,341 $ 1,173,744 |
Property and Equipment, net
Property and Equipment, net | 6 Months Ended |
Jun. 30, 2018 | |
Property, Plant and Equipment [Abstract] | |
Property and Equipment, net | 6. Property and Equipment, net. Property and equipment, net consists of the following: June 30, 2018 December 31, 2017 Computer equipment $ 27,915 $ 27,915 Furniture and equipment 181,868 169,931 Leasehold improvements 152,708 152,708 362,491 350,554 Less: Accumulated depreciation (175,360 ) (159,169 ) Total property and equipment, net $ 187,131 $ 191,385 Depreciation expense was $8,176 and $16,191, respectively, for the three and six-month six-month |
Accrued Expenses and Other Liab
Accrued Expenses and Other Liabilities | 6 Months Ended |
Jun. 30, 2018 | |
Payables and Accruals [Abstract] | |
Accrued Expenses and Other Liabilities | 7. Accrued Expenses and Other Liabilities. Accrued expenses and other liabilities consist of the following: June 30, 2018 December 31, 2017 Accrued preclinical and clinical trial expenses $ 1,251,568 $ 970,649 Accrued professional fees 338,098 227,457 Accrued compensation and benefits 232,847 821,935 Accrued license fees 305,000 252,500 Deferred rent and lease incentive 27,184 24,011 Other 4,738 24,035 Current accrued expenses and other liabilities 2,159,435 2,320,587 Deferred rent and lease incentive - non-current 143,335 157,456 Non-current 143,335 157,456 Total accrued expenses and other liabilities $ 2,302,770 $ 2,478,043 |
Commitments and Contingencies
Commitments and Contingencies | 6 Months Ended |
Jun. 30, 2018 | |
Commitments and Contingencies Disclosure [Abstract] | |
Commitments and Contingencies | 8. Commitments and Contingencies. a. LICENSE AGREEMENT WITH NORTHWESTERN UNIVERSITY. CPP-115. Under the license agreement with Northwestern, the Company is responsible for continued research and development of any resulting product candidates. As of June 30, 2018, the Company has paid $424,885 in connection with the license and has accrued license fees of $305,000 in the accompanying June 30, 2018 consolidated balance sheet for expenses, maintenance fees and milestones. In addition, the Company is obligated to pay certain milestone payments in future years relating to clinical development activities with respect to CPP-115, CPP-115 Recently, the Company became aware that certain patents granted to Northwestern to a new GABA aminotransferase inhibitor and derivative of vigabatrin were derived from CPP-115. b. LICENSE AGREEMENT WITH NEW YORK UNIVERSITY AND THE FEINSTEIN INSTITUTE FOR MEDICAL RESEARCH. c. LICENSE AGREEMENT WITH BIOMARIN ® Under the License Agreement, the Company has agreed to pay: (i) royalties to BioMarin for seven years from the first commercial sale of Firdapse ® ® Additionally, the Company’s license agreement with BioMarin requires the Company to pay certain milestone payments that BioMarin is obligated to pay to both a third-party licensor of the rights that have been sublicensed to the Company and to the former stockholders of Huxley Pharmaceuticals (“Huxley”) under an earlier stock purchase agreement between BioMarin and the former Huxley stockholders. With respect to the third party licensor of the rights that have been sublicensed to the Company, the Company has agreed to pay: (i) $150,000 upon acceptance by the FDA of a filing of an NDA for Firdapse ® ® ® With respect to the former Huxley stockholders, the Company had agreed that it would pay the following milestone payments if either of the following milestones were satisfied before April 20, 2018: (i) $2,425,000 upon acceptance by the FDA of a filing of an NDA for Firdapse ® ® ® The Company also agreed to share in the cost of certain post-marketing studies being conducted by BioMarin, and, as of June 30, 2018, the Company had paid BioMarin $3.8 million related to expenses in connection with Firdapse ® d. AGREEMENTS FOR DRUG DEVELOPMENT, PRE-CLINICAL |
Income Taxes
Income Taxes | 6 Months Ended |
Jun. 30, 2018 | |
Income Tax Disclosure [Abstract] | |
Income Taxes | 9. Income Taxes. The Company is subject to income taxes in the U.S. federal jurisdiction and various states jurisdictions. Tax regulations within each jurisdiction are subject to the interpretation of the related tax laws and regulations and require significant judgment to apply. The Company is not subject to U.S. federal, state and local tax examinations by tax authorities for any years before 2014. If the Company were to subsequently record an unrecognized tax benefit, associated penalties and tax related interest expense would be reported as a component of income tax expense. The Company’s net deferred tax asset has a 100% valuation allowance at June 30, 2018 and December 31, 2017 as the Company believes that it is more likely than not that the deferred tax asset will not be realized. |
Stockholders' Equity
Stockholders' Equity | 6 Months Ended |
Jun. 30, 2018 | |
Equity [Abstract] | |
Stockholders' Equity | 10. Stockholders’ Equity. 2016 Shelf Registration Statement On December 23, 2016, the Company filed a shelf Registration Statement on Form S-3 No. 333-215315) 2017 Shelf Registration Statement On July 12, 2017, the Company filed a universal shelf Registration Statement on Form S-3 No. 333-219259) (a) On November 28, 2017, the Company filed a prospectus supplement and offered for sale 16,428,572 shares of its common stock at a price of $3.50 per share in an underwritten public offering. The Company received gross proceeds in the public offering of approximately $57.5 million before underwriting commission and incurred expenses of approximately $3.7 million. As of June 30, 2018, there is approximately $92.5 million available for future sale under the 2017 Shelf Registration Statement. |
Stock Compensation
Stock Compensation | 6 Months Ended |
Jun. 30, 2018 | |
Disclosure of Compensation Related Costs, Share-based Payments [Abstract] | |
Stock Compensation | 11. Stock Compensation. Stock Options During the three and six-month six-month six-month During the three and six-month six-month six-month During the three and six-month six-months As of June 30, 2018, there was approximately $6,130,000 of unrecognized compensation expense related to non-vested Restricted Stock Units No restricted stock units were granted during the three and six-month six-months six-month Common Stock During both the three and six-month six-month six-months |
Subsequent Events
Subsequent Events | 6 Months Ended |
Jun. 30, 2018 | |
Subsequent Events [Abstract] | |
Subsequent Events | 12. Subsequent Events. Subsequent to quarter end, effective July 26, 2018, the Company settled a dispute with BioMarin and the former Huxley stockholders regarding the milestone payments due to the former Huxley stockholders if certain milestones are achieved by the Company. See Note 8. |
Basis of Presentation and Sig19
Basis of Presentation and Significant Accounting Policies (Policies) | 6 Months Ended |
Jun. 30, 2018 | |
Accounting Policies [Abstract] | |
INTERIM FINANCIAL STATEMENTS | a. INTERIM FINANCIAL STATEMENTS. 10-Q In the opinion of management, the accompanying unaudited interim consolidated financial statements of the Company contain all adjustments (consisting of only normal recurring adjustments) necessary to present fairly the financial position of the Company as of the dates and for the periods presented. Accordingly, these consolidated statements should be read in conjunction with the financial statements and notes thereto for the year ended December 31, 2017 included in the 2017 Annual Report on Form 10-K |
PRINCIPLES OF CONSOLIDATION | b. PRINCIPLES OF CONSOLIDATION |
USE OF ESTIMATES | c. USE OF ESTIMATES. |
CASH AND CASH EQUIVALENTS | d. CASH AND CASH EQUIVALENTS. |
INVESTMENTS | e. INVESTMENTS Short-term bond fund The short-term bond fund is classified in trading securities. Trading securities are recorded at fair value based on the closing market price of the security. For trading securities, the Company recognizes realized gains and losses and unrealized gains and losses to earnings. At June 30, 2018 and December 31, 2017, the only investment classified as trading securities was the short-term bond fund. Unrealized gain (loss) on trading securities was $29,431 and ($29,430), respectively, for the three and six months ended June 30, 2018, and $0 and $29,430 for the three and six months ended June 30, 2017 and is included in other income, net in the accompanying consolidated statements of operations. U.S. Treasuries U.S. Treasuries are classified as available-for-sale available-for-sale Available-for-sale non-current available-for-sale available-for-sale available-for-sale |
PREPAID EXPENSES AND OTHER CURRENT ASSETS | f. PREPAID EXPENSES AND OTHER CURRENT ASSETS pre-commercialization pre-clinical |
FAIR VALUE OF FINANCIAL INSTRUMENTS | g. FAIR VALUE OF FINANCIAL INSTRUMENTS. |
FAIR VALUE MEASUREMENTS | h. FAIR VALUE MEASUREMENTS. Level 1 inputs utilize quoted prices (unadjusted) in active markets for identical assets or liabilities that the Company has the ability to access at the measurement date. Level 2 inputs are inputs other than quoted prices included in Level 1 that are observable for the asset or liability, either directly or indirectly. Level 2 inputs may include quoted prices for similar assets and liabilities in active markets, as well as inputs that are observable for the asset or liability (other than quoted prices), such as interest rates, foreign exchange rates, and yield curves that are observable at commonly quoted intervals. Level 3 inputs are unobservable inputs for the asset or liability, which are typically based on an entity’s own assumptions, as there is little, if any, related market activity. In instances where the determination of the fair value measurement is based on inputs from different levels of the fair value hierarchy, the level in the fair value hierarchy within which the entire fair value measurement falls is based on the lowest level input that is significant to the fair value measurement in its entirety. The Company’s assessment of the significance of a particular input to the fair value measurement in its entirety requires judgment, and considers factors specific to the asset or liability. Fair Value Measurements at Reporting Date Using Balances as of Quoted Prices in Significant Significant Cash and cash equivalents: Money market funds $ 9,496,648 $ 9,496,648 $ — $ — Short-term investments: Short-term bond fund $ 26,530,474 $ 26,530,474 $ — $ — U.S. Treasuries $ 31,990,482 $ — $ 31,990,482 $ — Investments: U.S. Treasuries $ 5,005,321 $ — $ 5,005,321 $ — Balances as of Quoted Prices in Significant Significant Cash and cash equivalents: Money market funds $ 56,820,688 $ 56,820,688 $ — $ — Short-term investments: Short-term bond fund $ 26,516,711 $ 26,516,711 $ — $ — |
WARRANTS LIABILITY | i. WARRANTS LIABILITY. |
STOCK-BASED COMPENSATION | j. STOCK-BASED COMPENSATION. As of June 30, 2018, there were outstanding stock options to purchase 7,719,166 shares of common stock, of which stock options to purchase 4,096,662 shares of common stock were exercisable as of June 30, 2018. For the three and six-month Three months ended June 30, Six months ended June 30, 2018 2017 2018 2017 Research and development $ 285,625 $ 223,552 $ 579,940 $ 429,904 General and administrative 505,882 415,017 1,182,907 962,809 Total stock-based compensation $ 791,507 $ 638,569 $ 1,762,847 $ 1,392,713 |
COMPREHENSIVE INCOME (LOSS) | k. COMPREHENSIVE INCOME (LOSS). available-for-sale |
NET LOSS PER SHARE | l. NET LOSS PER SHARE. June 30, 2018 2017 Options to purchase common stock 7,719,166 6,090,000 Warrants to purchase common stock — 675,000 Unvested restricted stock — 26,667 Potential equivalent common stock excluded 7,719,166 6,791,667 Potentially dilutive options to purchase common stock as of June 30, 2018 have exercise prices ranging from $0.79 to $4.64. Potentially dilutive options to purchase common stock as of June 30, 2017 had exercise prices ranging from $0.47 to $4.64. Potentially dilutive warrants to purchase common stock as of June 30, 2017 had an exercise price of $2.08 and expired in August 2017. |
RECENTLY ISSUED ACCOUNTING STANDARDS | m. RECENTLY ISSUED ACCOUNTING STANDARDS . No. 2016-02, Leases (Topic 842) 2016-02 In May 2017, the FASB issued ASU No. 2017-09, Compensation – Stock Compensation (Topic 718): Scope of Modification Accounting 2017-09 In June 2018, the FASB issued ASU No. 2018-07, Compensation - Stock Compensation (Topic 718): Improvements to Nonemployee Share-Based Payment Accounting 2018-07 |
RECLASSIFICATIONS | n. RECLASSIFICATIONS. |
Basis of Presentation and Sig20
Basis of Presentation and Significant Accounting Policies (Tables) | 6 Months Ended |
Jun. 30, 2018 | |
Accounting Policies [Abstract] | |
Fair Value Measurement Specific to Assets or Liability | The Company’s assessment of the significance of a particular input to the fair value measurement in its entirety requires judgment, and considers factors specific to the asset or liability. Fair Value Measurements at Reporting Date Using Balances as of Quoted Prices in Significant Significant Cash and cash equivalents: Money market funds $ 9,496,648 $ 9,496,648 $ — $ — Short-term investments: Short-term bond fund $ 26,530,474 $ 26,530,474 $ — $ — U.S. Treasuries $ 31,990,482 $ — $ 31,990,482 $ — Investments: U.S. Treasuries $ 5,005,321 $ — $ 5,005,321 $ — Balances as of Quoted Prices in Significant Significant Cash and cash equivalents: Money market funds $ 56,820,688 $ 56,820,688 $ — $ — Short-term investments: Short-term bond fund $ 26,516,711 $ 26,516,711 $ — $ — |
Stock-Based Compensation Expense | For the three and six-month Three months ended June 30, Six months ended June 30, 2018 2017 2018 2017 Research and development $ 285,625 $ 223,552 $ 579,940 $ 429,904 General and administrative 505,882 415,017 1,182,907 962,809 Total stock-based compensation $ 791,507 $ 638,569 $ 1,762,847 $ 1,392,713 |
Potential Shares Excluded from Determination of Basic and Diluted Net Loss Per Share | l. NET LOSS PER SHARE. June 30, 2018 2017 Options to purchase common stock 7,719,166 6,090,000 Warrants to purchase common stock — 675,000 Unvested restricted stock — 26,667 Potential equivalent common stock excluded 7,719,166 6,791,667 |
Warrants Liability, at Fair V21
Warrants Liability, at Fair Value (Tables) | 6 Months Ended |
Jun. 30, 2018 | |
Text Block [Abstract] | |
Summary of Company's Warrants Liability Activity | The following table rolls forward the fair value of the Company’s warrants liability activity for the three and six-month Three months ended Six months ended June 30, 2017 June 30, 2017 Fair value, beginning of period $ 519,461 $ 122,226 Issuance of warrants — — Exercise of warrants (309,130 ) (309,130 ) Change in fair value (210,331 ) 186,904 Fair value, end of period $ — $ — |
Investments (Tables)
Investments (Tables) | 6 Months Ended |
Jun. 30, 2018 | |
Investments, Debt and Equity Securities [Abstract] | |
Summary of Available-for-Sale Investments by Security type | Available-for-sale investments by security type were as follows: Amortized Gross Gross Estimated At June 30, 2018: U.S. Treasuries - ST $ 32,007,257 $ — $ (16,775 ) $ 31,990,482 U.S. Treasuries - LT 5,025,044 — (19,723 ) 5,005,321 Total $ 37,032,301 $ — $ (36,498 ) $ 36,995,803 |
Estimated Fair Values of Available for Sale Securities | The estimated fair values of available-for-sale securities at June 30, 2018, by contractual maturity, are summarized as follows: June 30, 2018 Due in one year or less $ 31,990,482 Due after one year but within two years 5,005,321 $ 36,995,803 |
Prepaid Expenses and Other Cu23
Prepaid Expenses and Other Current Assets (Tables) | 6 Months Ended |
Jun. 30, 2018 | |
Text Block [Abstract] | |
Prepaid Expenses and Other Current Assets | Prepaid expenses and other current assets consist of the following: June 30, 2018 December 31, 2017 Prepaid research fees $ 211,124 $ 388,977 Prepaid insurance 306,689 638,139 Prepaid pre-commercialization 8,925 65,000 Prepaid subscription fees 69,068 23,347 Prepaid rent 20,828 — Other 60,707 58,281 Total prepaid expenses and other current assets $ 677,341 $ 1,173,744 |
Property and Equipment, net (Ta
Property and Equipment, net (Tables) | 6 Months Ended |
Jun. 30, 2018 | |
Property, Plant and Equipment [Abstract] | |
Property and Equipment, net | Property and equipment, net consists of the following: June 30, 2018 December 31, 2017 Computer equipment $ 27,915 $ 27,915 Furniture and equipment 181,868 169,931 Leasehold improvements 152,708 152,708 362,491 350,554 Less: Accumulated depreciation (175,360 ) (159,169 ) Total property and equipment, net $ 187,131 $ 191,385 |
Accrued Expenses and Other Li25
Accrued Expenses and Other Liabilities (Tables) | 6 Months Ended |
Jun. 30, 2018 | |
Payables and Accruals [Abstract] | |
Schedule of Accrued Expenses and Other Liabilities | Accrued expenses and other liabilities consist of the following: June 30, 2018 December 31, 2017 Accrued preclinical and clinical trial expenses $ 1,251,568 $ 970,649 Accrued professional fees 338,098 227,457 Accrued compensation and benefits 232,847 821,935 Accrued license fees 305,000 252,500 Deferred rent and lease incentive 27,184 24,011 Other 4,738 24,035 Current accrued expenses and other liabilities 2,159,435 2,320,587 Deferred rent and lease incentive - non-current 143,335 157,456 Non-current 143,335 157,456 Total accrued expenses and other liabilities $ 2,302,770 $ 2,478,043 |
Basis of Presentation and Sig26
Basis of Presentation and Significant Accounting Policies - Additional Information (Detail) - USD ($) | 1 Months Ended | 3 Months Ended | 6 Months Ended | ||
Oct. 31, 2011 | Jun. 30, 2018 | Jun. 30, 2017 | Jun. 30, 2018 | Jun. 30, 2017 | |
Summary Of Basis Of Presentation And Significant Accounting Policies [Line Items] | |||||
Maximum maturity period of cash and cash equivalent | Three months | ||||
Number of options outstanding | 7,719,166 | 7,719,166 | |||
Number of options exercisable | 4,096,662 | 4,096,662 | |||
Stock option exercise price range, Minimum | $ 0.79 | $ 0.47 | |||
Stock option exercise price range, Maximum | $ 4.64 | 4.64 | |||
Potentially dilutive warrants to purchase common stock | $ 2.08 | $ 2.08 | |||
Lease Expiration Date | Nov. 30, 2022 | ||||
October 28, 2011 Warrants [Member] | |||||
Summary Of Basis Of Presentation And Significant Accounting Policies [Line Items] | |||||
Warrants issued in offering | 1,523,370 | ||||
October 28, 2011 Warrants [Member] | Warrants Liability, at Fair Value [Member] | |||||
Summary Of Basis Of Presentation And Significant Accounting Policies [Line Items] | |||||
Warrants expiration date | May 2, 2017 | ||||
Other Income, Net [Member] | |||||
Summary Of Basis Of Presentation And Significant Accounting Policies [Line Items] | |||||
Unrealized gain(loss),trading securities | $ 29,431 | $ 0 | $ (29,430) | $ 29,430 | |
Minimum [Member] | |||||
Summary Of Basis Of Presentation And Significant Accounting Policies [Line Items] | |||||
Minimum amortization period of compensation cost on straight line basis | 1 year | ||||
Maximum [Member] | |||||
Summary Of Basis Of Presentation And Significant Accounting Policies [Line Items] | |||||
Minimum amortization period of compensation cost on straight line basis | 3 years |
Basis of Presentation and Sig27
Basis of Presentation and Significant Accounting Policies - Fair Value Measurement Specific to Assets or Liability (Detail) - USD ($) | Jun. 30, 2018 | Dec. 31, 2017 |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ||
Investments | $ 5,005,321 | |
Short-Term Bond Fund [Member] | ||
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ||
Investments Fair Value Disclosure | 26,530,474 | $ 26,516,711 |
U.S. Treasuries [Member] | ||
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ||
Investments Fair Value Disclosure | 31,990,482 | |
Investments | 5,005,321 | |
Money Market Funds [Member] | ||
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ||
Money market funds | 9,496,648 | 56,820,688 |
Quoted Prices in Active Markets for Identical Assets/Liabilities (Level 1) [Member] | Short-Term Bond Fund [Member] | ||
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ||
Investments Fair Value Disclosure | 26,530,474 | 26,516,711 |
Quoted Prices in Active Markets for Identical Assets/Liabilities (Level 1) [Member] | Money Market Funds [Member] | ||
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ||
Money market funds | 9,496,648 | $ 56,820,688 |
Significant Other Observable Inputs (Level 2) [Member] | U.S. Treasuries [Member] | ||
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ||
Investments Fair Value Disclosure | 31,990,482 | |
Investments | $ 5,005,321 |
Basis of Presentation and Sig28
Basis of Presentation and Significant Accounting Policies - Stock-Based Compensation Expense (Detail) - USD ($) | 3 Months Ended | 6 Months Ended | ||
Jun. 30, 2018 | Jun. 30, 2017 | Jun. 30, 2018 | Jun. 30, 2017 | |
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items] | ||||
Stock-based compensation | $ 791,507 | $ 638,569 | $ 1,762,847 | $ 1,392,713 |
Research and Development [Member] | ||||
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items] | ||||
Stock-based compensation | 285,625 | 223,552 | 579,940 | 429,904 |
General and Administrative [Member] | ||||
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items] | ||||
Stock-based compensation | $ 505,882 | $ 415,017 | $ 1,182,907 | $ 962,809 |
Basis of Presentation and Sig29
Basis of Presentation and Significant Accounting Policies - Potential Shares Excluded from Determination of Basic and Diluted Net Loss Per Share (Detail) - shares | 6 Months Ended | |
Jun. 30, 2018 | Jun. 30, 2017 | |
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] | ||
Potential equivalent common stock excluded | 7,719,166 | 6,791,667 |
Options to Purchase Common Stock [Member] | ||
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] | ||
Potential equivalent common stock excluded | 7,719,166 | 6,090,000 |
Warrants Liability, at Fair Value [Member] | ||
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] | ||
Potential equivalent common stock excluded | 675,000 | |
Unvested Restricted Stock [Member] | ||
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] | ||
Potential equivalent common stock excluded | 26,667 |
Warrants Liability, at Fair V30
Warrants Liability, at Fair Value - Additional Information (Detail) - USD ($) | 1 Months Ended | 3 Months Ended | 6 Months Ended | |
Oct. 31, 2011 | Jun. 30, 2017 | Jun. 30, 2018 | Jun. 30, 2017 | |
Class of Warrant or Right [Line Items] | ||||
Recognition of warrants fair value at date of issuance | $ 0 | $ 0 | ||
Proceeds of Warrants | $ 1,805,437 | |||
October 28, 2011 Warrants [Member] | Warrants Liability, at Fair Value [Member] | ||||
Class of Warrant or Right [Line Items] | ||||
Recognition of warrants fair value at date of issuance | $ 1,300,000 | |||
Warrants expiration date | May 2, 2017 | |||
Number of warrants exercised during the period | 613,913 | 613,913 | ||
Proceeds of Warrants | $ 798,087 | $ 798,087 |
Warrants Liability, at Fair V31
Warrants Liability, at Fair Value - Summary of Company's Warrants Liability Activity (Detail) - USD ($) | 3 Months Ended | 6 Months Ended |
Jun. 30, 2017 | Jun. 30, 2017 | |
Fair Value Disclosures [Abstract] | ||
Fair value, beginning of period | $ 519,461 | $ 122,226 |
Issuance of warrants | 0 | 0 |
Exercise of warrants | (309,130) | (309,130) |
Change in fair value | $ (210,331) | $ 186,904 |
Investment - Summary of Availab
Investment - Summary of Available-for-Sale Investments by Security type (Detail) | 6 Months Ended |
Jun. 30, 2018USD ($) | |
Net Investment Income [Line Items] | |
Amortized cost | $ 37,032,301 |
Gross Unrealized Gains | 0 |
Gross Unrealized Losses | (36,498) |
Estimated Fair Value | 36,995,803 |
U.S. Treasuries - ST [Member] | |
Net Investment Income [Line Items] | |
Amortized cost | 32,007,257 |
Gross Unrealized Gains | 0 |
Gross Unrealized Losses | (16,775) |
Estimated Fair Value | 31,990,482 |
U.S. Treasuries - LT [Member] | |
Net Investment Income [Line Items] | |
Amortized cost | 5,025,044 |
Gross Unrealized Gains | 0 |
Gross Unrealized Losses | (19,723) |
Estimated Fair Value | $ 5,005,321 |
Investments - Additional Inform
Investments - Additional Information (Detail) - USD ($) | 6 Months Ended | |
Jun. 30, 2018 | Jun. 30, 2017 | |
Investments, Debt and Equity Securities [Abstract] | ||
Realized gains losses from available for sale securities | $ 0 | $ 0 |
Investment - Estimated Fair Val
Investment - Estimated Fair Values of Available for Sale Securities (Detail) | Jun. 30, 2018USD ($) |
Investments, Debt and Equity Securities [Abstract] | |
Due in one year or less | $ 31,990,482 |
Due after one year but within two years | 5,005,321 |
Estimated Fair Value | $ 36,995,803 |
Prepaid Expenses and Other Cu35
Prepaid Expenses and Other Current Assets - Prepaid Expenses and Other Current Assets (Detail) - USD ($) | Jun. 30, 2018 | Dec. 31, 2017 |
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract] | ||
Prepaid research fees | $ 211,124 | $ 388,977 |
Prepaid insurance | 306,689 | 638,139 |
Prepaid pre-commercialization fees | 8,925 | 65,000 |
Prepaid subscription fees | 69,068 | 23,347 |
Prepaid rent | 20,828 | |
Other | 60,707 | 58,281 |
Total prepaid expenses and other current assets | $ 677,341 | $ 1,173,744 |
Property and Equipment, net - P
Property and Equipment, net - Property and Equipment, net (Detail) - USD ($) | Jun. 30, 2018 | Dec. 31, 2017 |
Property, Plant and Equipment [Line Items] | ||
Property and equipment, gross | $ 362,491 | $ 350,554 |
Less: Accumulated depreciation | (175,360) | (159,169) |
Total property and equipment, net | 187,131 | 191,385 |
Computer Equipment [Member] | ||
Property, Plant and Equipment [Line Items] | ||
Property and equipment, gross | 27,915 | 27,915 |
Furniture and Equipment [Member] | ||
Property, Plant and Equipment [Line Items] | ||
Property and equipment, gross | 181,868 | 169,931 |
Leasehold Improvements [Member] | ||
Property, Plant and Equipment [Line Items] | ||
Property and equipment, gross | $ 152,708 | $ 152,708 |
Property and Equipment, net - A
Property and Equipment, net - Additional Information (Detail) - USD ($) | 3 Months Ended | 6 Months Ended | ||
Jun. 30, 2018 | Jun. 30, 2017 | Jun. 30, 2018 | Jun. 30, 2017 | |
Property, Plant and Equipment [Abstract] | ||||
Depreciation expenses | $ 8,176 | $ 12,957 | $ 16,191 | $ 25,915 |
Accrued Expenses and Other Li38
Accrued Expenses and Other Liabilities - Schedule of Accrued Expenses and Other Liabilities (Detail) - USD ($) | Jun. 30, 2018 | Dec. 31, 2017 |
Payables and Accruals [Abstract] | ||
Accrued preclinical and clinical trial expenses | $ 1,251,568 | $ 970,649 |
Accrued professional fees | 338,098 | 227,457 |
Accrued compensation and benefits | 232,847 | 821,935 |
Accrued license fees | 305,000 | 252,500 |
Deferred rent and lease incentive | 27,184 | 24,011 |
Other | 4,738 | 24,035 |
Current accrued expenses and other liabilities | 2,159,435 | 2,320,587 |
Deferred rent and lease incentive - non-current | 143,335 | 157,456 |
Non-current accrued expenses and other liabilities | 143,335 | 157,456 |
Total accrued expenses and other liabilities | $ 2,302,770 | $ 2,478,043 |
Commitments and Contingencies -
Commitments and Contingencies - Additional Information (Detail) - USD ($) | Jul. 26, 2018 | Apr. 30, 2018 | Jun. 30, 2018 | Dec. 31, 2017 |
Commitments [Line Items] | ||||
Accrued license fees | $ 305,000 | $ 252,500 | ||
Northwestern License Agreement [Member] | ||||
Commitments [Line Items] | ||||
Accrued license fees | 305,000 | |||
Future milestone payment | 300,000 | |||
Northwestern License Agreement [Member] | License [Member] | ||||
Commitments [Line Items] | ||||
License fee paid | $ 424,885 | |||
License Agreement with BioMarin [Member] | ||||
Commitments [Line Items] | ||||
Date on which strategic collaboration is entered into | Oct. 26, 2012 | |||
Royalty agreement period | 7 years | |||
Net sales royalty threshold | $ 100,000,000 | |||
Milestone Payment Description | However, prior to April 20, 2018, the Company was advised that the former Huxley stockholders intended to take legal action against BioMarin and the Company seeking payment of the milestone payments due to them even if the milestones were achieved after their expiration date (April 20, 2018). | |||
Costs paid for Firdapse joint studies | $ 3,800,000 | |||
License Agreement with BioMarin [Member] | Minimum [Member] | ||||
Commitments [Line Items] | ||||
Percentage of royalty on net sales | 7.00% | |||
License Agreement with BioMarin [Member] | Maximum [Member] | ||||
Commitments [Line Items] | ||||
Percentage of royalty on net sales | 10.00% | |||
License Agreement with BioMarin [Member] | Third Party Licensor [Member] | ||||
Commitments [Line Items] | ||||
Milestone payment due upon NDA acceptance | $ 150,000 | |||
Milestone payment due upon new drug application approval | $ 3,000,000 | |||
License Agreement with BioMarin [Member] | Huxley [Member] | ||||
Commitments [Line Items] | ||||
Milestone payment due upon NDA acceptance | $ 2,425,000 | |||
Milestone payment due upon new drug application approval | $ 4,200,000 | |||
License Agreement with BioMarin [Member] | Subsequent Event [Member] | Huxley [Member] | ||||
Commitments [Line Items] | ||||
Milestone payment due upon NDA acceptance | $ 1,000,000 | |||
Milestone payment due upon new drug application approval | $ 1,000,000 |
Income Taxes - Additional Infor
Income Taxes - Additional Information (Detail) | 6 Months Ended | 12 Months Ended |
Jun. 30, 2018 | Dec. 31, 2017 | |
Income Tax Disclosure [Abstract] | ||
Valuation allowance | 100.00% | 100.00% |
Stockholders' Equity (2016 Shel
Stockholders' Equity (2016 Shelf Registration Statement) - Additional Information (Detail) | Dec. 23, 2016USD ($) |
2016 Shelf Registration Statement [Member] | |
Stockholders' Equity [Line Items] | |
Maximum dollar amount of common stock to be issued under shelf registration statement | $ 33,800,000 |
Stockholders' Equity (2017 Shel
Stockholders' Equity (2017 Shelf Registration Statement) - Additional Information (Detail) - USD ($) | Nov. 28, 2017 | Jun. 30, 2018 | Jul. 12, 2017 |
Underwritten Public Offering [Member] | |||
Stockholders' Equity [Line Items] | |||
Number of common stock sold in offering | 16,428,572 | ||
Common stock issued, price per share | $ 3.50 | ||
Gross proceeds from issuance of common stock | $ 57,500,000 | ||
Offering expenses | $ 3,700,000 | ||
2017 Shelf Registration Statement [Member] | |||
Stockholders' Equity [Line Items] | |||
Maximum dollar amount of securities to be issued under shelf registration statement | $ 150,000,000 | ||
Value of common stock available for future sale | $ 92,500,000 |
Stock Compensation - Additional
Stock Compensation - Additional Information (Detail) - USD ($) | 3 Months Ended | 6 Months Ended | ||
Jun. 30, 2018 | Jun. 30, 2017 | Jun. 30, 2018 | Jun. 30, 2017 | |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | ||||
Proceeds from exercise of stock options | $ 41,532 | |||
Employees [Member] | ||||
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | ||||
Common stock unit granted | 3,094 | 0 | 3,094 | 0 |
Stock-based compensation | $ 15,000 | $ 15,000 | ||
Restricted Stock Units (RSUs) [Member] | ||||
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | ||||
Stock-based compensation | $ 0 | $ 18,815 | $ 0 | $ 37,423 |
Restricted stock unit granted | 0 | 0 | 0 | 0 |
Options to Purchase Common Stock [Member] | ||||
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | ||||
Common stock unit granted | 945,000 | 15,000 | 2,717,500 | 1,535,000 |
Stock-based compensation | $ 776,510 | $ 619,754 | $ 1,747,850 | $ 1,355,290 |
Stock option vested during the period | 565,000 | 621,667 | 1,309,998 | 876,667 |
Stock option granted, contractual term | 7 years | 7 years | 7 years | 7 years |
Number of stock options exercised | 10,000 | 0 | 46,666 | 0 |
Proceeds from exercise of stock options | $ 8,500 | $ 41,532 | ||
Unrecognized compensation expense related to non-vested stock compensation awards granted under the Plan | $ 6,130,000 | $ 6,130,000 | ||
Expected remaining weighted average vesting period | 2 years 5 months 12 days |