Aldeyra Therapeutics (ALDX) 10-K 29 Mar 18 2017 FY Annual report Financial data

Document and Entity Information

Document and Entity Information - USD ($)	12 Months Ended
	Dec. 31, 2017	Mar. 29, 2018	Jun. 30, 2017
Document And Entity Information [Abstract]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 31, 2017
Document Fiscal Year Focus	2,017
Document Fiscal Period Focus	FY
Trading Symbol	ALDX
Entity Registrant Name	ALDEYRA THERAPEUTICS, INC.
Entity Central Index Key	1,341,235
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	No
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
Entity Filer Category	Smaller Reporting Company
Entity Common Stock, Shares Outstanding		19,664,921
Entity Public Float			$ 60,469,344

Balance Sheets

Balance Sheets - USD ($)	Dec. 31, 2017	Dec. 31, 2016
Current assets:
Cash and cash equivalents	$ 20,023,337	$ 12,015,061
Marketable securities	22,923,462	12,897,584
Prepaid expenses and other current assets	1,018,967	218,682
Total current assets	43,965,766	25,131,327
Deferred offering costs	165,930
Fixed assets, net	43,262	56,352
Total assets	44,174,958	25,187,679
Current liabilities:
Accounts payable	1,000,963	275,441
Accrued expenses	2,236,465	1,946,251
Current portion of credit facility	116,319	77,546
Total current liabilities	3,353,747	2,299,238
Credit facility, net of current portion and debt discount	1,220,192	1,238,624
Total liabilities	4,573,939	3,537,862
Commitments and contingencies (Note 11)
Stockholders' equity:
Preferred stock, $0.001 par value, 15,000,000 shares authorized, none issued and outstanding
Common stock, voting, $0.001 par value; 150,000,000 authorized and 19,137,639 and 12,576,325 shares issued and outstanding, respectively	19,138	12,576
Additional paid-in capital	139,241,635	98,938,446
Accumulated other comprehensive income (loss)	(17,831)	129
Accumulated deficit	(99,641,923)	(77,301,334)
Total stockholders' equity	39,601,019	21,649,817
Total liabilities and stockholders' equity	$ 44,174,958	$ 25,187,679

Balance Sheets (Parenthetical)

Balance Sheets (Parenthetical) - $ / shares	Dec. 31, 2017	Dec. 31, 2016
Statement of Financial Position [Abstract]
Preferred Stock, par value	$ 0.001	$ 0.001
Preferred Stock, shares authorized	15,000,000	15,000,000
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	19,137,639	12,576,325
Common stock, shares outstanding	19,137,639	12,576,325

Statements of Operations

Statements of Operations - USD ($)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Operating expenses:
Research and development	$ 16,302,568	$ 13,175,670
General and administrative	6,185,820	5,520,308
Loss from operations	(22,488,388)	(18,695,978)
Other income (expense):
Interest income	261,252	102,037
Interest expense	(113,453)	(105,509)
Total other income (expense), net	147,799	(3,472)
Net loss	$ (22,340,589)	$ (18,699,450)
Net loss per share - basic and diluted	$ (1.40)	$ (1.65)
Weighted average common shares outstanding - basic and diluted	15,921,884	11,352,230

Statements of Comprehensive Los

Statements of Comprehensive Loss - USD ($)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Statement of Comprehensive Income [Abstract]
Net loss	$ (22,340,589)	$ (18,699,450)
Other comprehensive income/(loss):
Unrealized gain/(loss) on marketable securities	(17,960)	8,490
Total other comprehensive income/(loss)	(17,960)	8,490
Comprehensive loss	$ (22,358,549)	$ (18,690,960)

Statements of Stockholders' Equ

Statements of Stockholders' Equity - USD ($)	Total	Common Voting Stock [Member]	Additional Paid-in Capital [Member]	Accumulated Other Comprehensive Income (Loss), Net of Tax [Member]	Accumulated Deficit [Member]
Beginning Balance at Jan. 01, 2016	$ 24,878,319	$ 9,713	$ 83,478,851	$ (8,361)	$ (58,601,884)
Beginning Balance, Shares at Jan. 01, 2016		9,712,521
Stock-based compensation	2,759,753		2,759,753
Issuance of common stock, net of issuance costs	12,613,623	$ 2,760	12,610,863
Issuance of common stock, net of issuance costs, Shares		2,760,000
Issuance of common stock, upon exercise of stock options	89,082	$ 103	88,979
Issuance of common stock, upon exercise of stock options, Shares		103,804
Other comprehensive income (loss)	8,490			8,490
Net loss	(18,699,450)				(18,699,450)
Ending Balance at Dec. 31, 2016	21,649,817	$ 12,576	98,938,446	129	(77,301,334)
Ending Balance, Shares at Dec. 31, 2016		12,576,325
Stock-based compensation	2,714,841		2,714,841
Issuance of common stock, net of issuance costs	37,469,611	$ 6,524	37,463,087
Issuance of common stock, net of issuance costs, Shares		6,523,055
Issuance of common stock, Employee Stock Purchase Plan	$ 125,292	$ 31	125,261
Issuance of common stock, upon exercise of stock options, Shares	0
Issuance of common stock, Employee Stock Purchase Plan, Shares		31,485
Issuance of common stock, Restricted Stock Units	$ 7	$ 7
Issuance of common stock, Restricted Stock Units, Shares		6,774
Other comprehensive income (loss)	(17,960)			(17,960)
Net loss	(22,340,589)				(22,340,589)
Ending Balance at Dec. 31, 2017	$ 39,601,019	$ 19,138	$ 139,241,635	$ (17,831)	$ (99,641,923)
Ending Balance, Shares at Dec. 31, 2017		19,137,639

Statements of Stockholders' Eq7

Statements of Stockholders' Equity (Parenthetical) - USD ($)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Common stock, net of issuance costs	$ 2,784,000	$ 1,189,000
Common Voting Stock [Member]
Common stock, net of issuance costs	2,784,000	1,189,000
Additional Paid-in Capital [Member]
Common stock, net of issuance costs	$ 2,784,000	$ 1,189,000

Statements of Cash Flows

Statements of Cash Flows - USD ($)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
CASH FLOWS FROM OPERATING ACTIVITIES:
Net loss	$ (22,340,589)	$ (18,699,450)
Adjustments to reconcile net loss to net cash used in operating activities:
Stock-based compensation	2,714,841	2,759,753
Amortization of debt discount - non-cash interest expense	20,341	27,314
Net amortization of premium on debt securities available for sale	129,245	266,106
Depreciation	37,849	35,792
Change in assets and liabilities:
Prepaid expenses and other current assets	(800,285)	278,870
Accounts payable	725,522	(575,719)
Accrued expenses	290,214	759,822
Net cash used in operating activities	(19,222,862)	(15,147,512)
CASH FLOWS FROM INVESTING ACTIVITIES:
Acquisitions of property and equipment	(24,759)	(11,810)
Purchases of marketable securities	(35,095,083)	(16,048,424)
Sales of marketable securities	24,922,000	15,835,000
Net cash used in investing activities	(10,197,842)	(225,234)
CASH FLOWS FROM FINANCING ACTIVITIES:
Proceeds from issuance of common stock, net of issuance costs	37,469,611	12,649,859
Proceeds from issuance of common stock under equity incentive plans	125,299	89,082
Deferred offering costs paid in cash	(165,930)
Net cash provided by financing activities	37,428,980	12,738,941
NET (DECREASE)/INCREASE IN CASH	8,008,276	(2,633,805)
CASH AND CASH EQUIVALENTS, BEGINNING OF PERIOD	12,015,061	14,648,866
CASH AND CASH EQUIVALENTS, END OF PERIOD	20,023,337	12,015,061
Cash paid during the period for:
Interest	$ 91,633	$ 78,128

Nature of Business

Nature of Business	12 Months Ended
	Dec. 31, 2017
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Nature of Business	1. NATURE OF BUSINESS Aldeyra Therapeutics, Inc. (the Company or Aldeyra) was incorporated in the state of Delaware on August 13, 2004 as Neuron Systems, Inc. On December 20, 2012, the Company changed its name to Aldexa Therapeutics, Inc. and, on March 17, 2014, the Company changed its name to Aldeyra Therapeutics, Inc. Aldeyra is developing next-generation medicines to improve the lives of patients with inflammatory diseases. The Company’s principal activities to date include raising capital and research and development activities.

Basis of Presentation and Signi

Basis of Presentation and Significant Accounting Policies	12 Months Ended
	Dec. 31, 2017
Accounting Policies [Abstract]
Basis of Presentation and Significant Accounting Policies	2. BASIS OF PRESENTATION AND SIGNIFICANT ACCOUNTING POLICIES Basis of Presentation Risks and Uncertainties The Company’s success will depend in part on its ability to obtain patents and product license rights, maintain trade secrets, and operate without infringing on the property rights of others, both in the United States and other countries. There can be no assurance that patents issued to or licensed by the Company will not be challenged, invalidated, circumvented, or that the rights granted thereunder will provide proprietary protection or competitive advantages to the Company. The Company believes that its cash, cash equivalents and marketable securities as of December 31, 2017, together with the proceeds from the Sales Agreement through March 29, 2018 and the amounts available under the Credit Facility, will be adequate to fund operations through the end of 2019 based on its current business plan. The Company will need to raise additional capital to implement its business plan. Additional funding may not be available to the Company on acceptable terms, or at all. If the Company is unable to secure additional capital, or meet financial covenants that could be implemented under the Company’s term loans in certain circumstances, it will be required to significantly decrease the amount of planned expenditures, and may be required to cease operations. Curtailment of operations would cause significant delays in the Company’s efforts to introduce its products to market, which is critical to the realization of its business plan and the future operations of the Company. Use of Estimates Segment Information Cash and Cash Equivalents RRAs are collateralized by deposits in the form of ‘Government Securities and Obligations’ for an amount not less than 102% of their value. The Company does not record an asset or liability related to the collateral as the Company is not permitted to sell or repledge the associated collateral. The Company has a policy that the collateral has at least an A (or equivalent) credit rating. The Company utilizes a third-party custodian to manage the exchange of funds and ensure that collateral received is maintained at 102% of the value of the RRAs on a daily basis. RRAs with original maturities of greater than three months are classified as marketable securities. Marketable Securities available-for-sale re-evaluates Fair Value of Financial Instruments Concentration of Credit Risk to-date. Intellectual Property Income Taxes Income Taxes The Company accounts for uncertain tax positions pursuant to ASC 740 which prescribes a recognition threshold and measurement process for financial statement recognition of uncertain tax positions taken or expected to be taken in a tax return. If the tax position meets this threshold, the benefit to be recognized is measured as the tax benefit having the highest likelihood of being realized upon ultimate settlement with the taxing authority. The Company recognizes interest accrued related to unrecognized tax benefits and penalties in the provision for income taxes. Management is not aware of any uncertain tax positions. Research and Development Costs Preclinical and clinical trial expenses relate to third-party services, subject-related fees at the sites where the Company’s clinical trials are being conducted, laboratory costs, analysis costs, toxicology studies and investigator fees. Costs associated with these expenses are generally payable on the passage of time or when certain milestones are achieved. Expense is recorded during the period incurred or in the period in which a milestone is achieved. In order to ensure that the Company has adequately provided for preclinical and clinical expenses during the proper period, the Company maintains an accrual to cover these expenses. These accruals are assessed on a quarterly basis and are based on such assumptions as expected total cost, the number of subjects and clinical trial sites and length of the study. Actual results may differ from these estimates and could have a material impact on the Company’s reported results. The Company’s historical accrual estimates have not been materially different from actual costs. Stock-Based Compensation Compensation – Stock Compensation Equity instruments issued to nonemployees are accounted for under the provisions of ASC 718 and ASC 505-50, Equity – Equity-Based Payments to Non-Employees From time to time the Company may grant awards with performance conditions necessary to be achieved in order to vest in the award. The Company records compensation expense for those awards over the vesting period of the award to the extent the performance conditions are deemed probable of achievement. From time to time the Company may grant awards with a market condition necessary to be achieved in order to vest in the award. The Company records compensation expense for those awards over the vesting period of the award on a straight-line basis utilizing Monte Carlo simulations to estimate the timing and number of shares that are most likely to vest. Comprehensive Loss non-owner Net Loss Per Share – Basic net loss per share available to common stockholders is calculated by dividing the net loss available to common stockholders by the weighted-average number of common shares outstanding during the period, without consideration for common stock equivalents. Diluted net loss per share available to common stockholders is computed by dividing the net loss available to common stockholders by the weighted-average number of common share equivalents outstanding for the period determined using the treasury-stock method. For purposes of this calculation, stock options, restricted stock units and common stock warrants are considered to be common stock equivalents and are only included in the calculation of diluted net loss per share available to common stockholders when their effect is dilutive. Recent Accounting Pronouncements – In August 2016, the FASB issued Accounting Standards Update (ASU) No. 2016-15 (ASU 2016-15), Statement of Cash Flows ASU 2016-15 ASU 2016-15 In June 2016, the FASB issued ASU 2016-13, Financial Instrument-Credit Losses 2016-13). ASU 2016-13 ASU 2016-13 In March 2016, the FASB issued ASU No. 2016-09 Improvements to Employee Share-Based Payment Accounting 2016-09), 2016-09 In February 2016, the FASB issued ASU No. 2016-02 2016-02), Leases 2016-02 right-of-use ASU 2016-02 In January 2016, the FASB issued ASU No. 2016-01 , Recognition and Measurement of Financial Assets and Financial Liabilities 2016-01). 2016-01 2016-01 2016-01 In November 2015, the FASB issued ASU No. 2015-17 , Income Taxes 2015-17). 2015-17 tax-paying 2015-17. 2015-17 In April 2015, the FASB issued ASU No. 2015-03, Simplifying the Presentation of Debt Issuance Costs 2015-03). 2015-03 2015-03 In May 2014, the FASB issued ASU No. 2014-09, Revenue from Contracts with Customers Revenue Recognition ASU 2014-09

Net Loss Per Share

Net Loss Per Share	12 Months Ended
	Dec. 31, 2017
Earnings Per Share [Abstract]
Net Loss Per Share	3. NET LOSS PER SHARE For the years ended December 31, 2017 and 2016, diluted weighted-average common shares outstanding is equal to basic weighted-average common shares due to the Company’s net loss position. The following potentially dilutive securities outstanding have been excluded from the computation of diluted weighted-average shares outstanding, because such securities had an antidilutive impact: Years ended December 31, 2017 2016 Options to purchase common stock 2,246,857 1,498,585 Warrants to purchase common stock 1,384,608 1,384,608 Restricted stock units 157,128 27,096 Total of common stock equivalents 3,788,593 2,910,289

Cash, Cash Equivalents and Mark

Cash, Cash Equivalents and Marketable Securities	12 Months Ended
	Dec. 31, 2017
Cash and Cash Equivalents [Abstract]
Cash, Cash Equivalents and Marketable Securities	4. CASH, CASH EQUIVALENTS AND MARKETABLE SECURITIES At December 31, 2017, cash, cash equivalents and marketable securities were comprised of: Carrying Unrecognized Unrecognized Estimated Fair Cash and Cash Current Cash $ 979,485 $ — $ — $ 979,485 $ 979,485 $ — Money market funds 1,043,852 — — 1,043,852 1,043,852 — U.S. reverse repurchase agreements 18,000,000 — — 18,000,000 18,000,000 — U.S. government agency securities 22,941,293 — (17,831 ) 22,923,462 — 22,923,462 Available for Sale(1) 40,941,293 — (17,831 ) 40,923,462 18,000,000 22,923,462 Total Cash, cash equivalents and current marketable securities $ 20,023,337 $ 22,923,462 (1) Available for sale securities are reported at fair value with unrealized gains and losses reported net of taxes, if material, in other comprehensive income. The contractual maturities of all available for sale securities are less than one year at December 31, 2017.

Fair Value Measurements

Fair Value Measurements	12 Months Ended
	Dec. 31, 2017
Fair Value Disclosures [Abstract]
Fair Value Measurements	5. FAIR VALUE MEASUREMENTS 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 are performed in a manner to maximize the use of observable inputs and minimize the use of unobservable inputs. ASC 820, Fair Value Measurements Level 1 Level 2 Level 3 There were no liabilities measured at fair value at December 31, 2017 or 2016, respectively. December 31, 2017 Level 1 Level 2 Level 3 Total Assets: Money market funds(a) $ 1,043,852 $ — $ — $ 1,043,852 U.S. reverse repurchase agreements(b) — 18,000,000 — 18,000,000 U.S. government agency securities(b) — 22,923,462 — 22,923,462 Total assets at fair value $ 1,043,852 $ 40,923,462 $ — $ 41,967,314 December 31, 2016 Level 1 Level 2 Level 3 Total Assets: Money market funds(a) $ 70,212 $ — $ — $ 70,212 U.S. reverse repurchase agreements(b) — 11,550,000 — 11,550,000 U.S. government agency securities(b) — 12,897,584 — 12,897,584 Total assets at fair value $ 70,212 $ 24,447,584 $ — $ 24,517,796 (a) Money market funds included in cash and cash equivalents in the consolidated balance sheets, are valued at quoted market prices in active markets. (b) U.S. reverse repurchase agreements and U.S. government agency securities are recorded at fair market values, which are determined based on the most recent observable inputs for similar instruments in active markets or quoted prices for identical or similar instruments in markets that are not active or are directly or indirectly observable. Financial instruments including cash equivalents and accounts payable are carried in the financial statements at amounts that approximate their fair value based on the short maturities of those instruments. The carrying amount of the Company’s term loan under its credit facility approximates market rates currently available to the Company. Marketable securities are carried at fair value.

Accrued Expenses

Accrued Expenses	12 Months Ended
	Dec. 31, 2017
Payables and Accruals [Abstract]
Accrued Expenses	6. ACCRUED EXPENSES Accrued expenses at December 31, 2017 and 2016 were: 2017 2016 Accrued compensation $ 788,570 $ 983,449 Accrued research and development 1,327,103 913,838 Accrued general & administrative 120,792 48,964 Accrued expenses $ 2,236,465 $ 1,946,251

Credit Facility

Credit Facility	12 Months Ended
	Dec. 31, 2017
Debt Disclosure [Abstract]
Credit Facility	7. CREDIT FACILITY The Company’s long-term debt obligation consists of amounts the Company is obligated to repay under its Credit Facility with Pacific Western, of which $1.4 million was outstanding as of December 31, 2017. The Company entered into the Credit Facility in April 2012 and it has been subsequently amended to make term loans in a principal amount of up to $5,000,000 available to the Company with proceeds to be used first to refinance outstanding loans from Pacific Western, second to fund expenses related to its clinical trials, and the remainder for general working capital purposes. The term loans are to be made available upon the following terms: (i) $2,000,000 was made available on November 10, 2014; and (ii) $3.0 million (the Tranche B Loan) which was made available to the Company in May 2016 following the satisfaction of certain conditions, including receipt of positive phase 2 data in noninfectious anterior uveitis. Each term loan accrues interest from its date of issue at a variable annual interest rate equal to the greater of 2.0% plus prime or 5.25% per annum. In November 2017, we amended our Credit Facility such that any term loan the Company draws is payable as interest-only prior to October 2018 and thereafter is payable in monthly installments of principal plus accrued interest over 36 months. The Credit Facility is collateralized by the Company’s assets, including its intellectual property. As of December 31, 2017, $1.4 million was outstanding under the Credit Facility. Future maturities of the existing term loans under the Credit Facility as of December 31, 2017 are as follows: 2018 $ 116,319 2019 465,278 2020 465,278 2021 348,958 Total $ 1,395,833 In conjunction with obtaining the November 2013 amended credit facility, the Company issued a warrant exercisable for 9,692 shares of Series B Preferred Stock with an exercise price of $5.16 per share and a term of seven years (Note 10). The warrant was valued at $178,000 and, together with the fair value of the warrant issued in connection with the April 12, 2012 Credit Facility ($88,000), was recorded as a discount on the Credit Facility. These discounts are being amortized using the effective interest method through the current maturity date of the Credit Facility in November 2021. All amendments to the credit facility were determined to be modifications in accordance with ASC 470, Debt At December 31, 2017 and 2016, the Credit Facility is shown net of a remaining debt discount of $59,000 and $80,000, respectively.

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Income Taxes	8. INCOME TAXES No provision for federal and state income taxes has been recorded as the Company has incurred losses since inception for tax purposes. Deferred income taxes reflect the net tax effects of temporary differences between the carrying amounts of assets and liabilities for financial reporting purposes and the amounts used for income tax purposes. In assessing the realizability of net deferred taxes in accordance with ASC 740, Income Taxes As of December 31, 2017, the Company had Federal and State income tax net operating loss (“NOL”) carryforwards of approximately $62.8 million and $59.4 million, respectively, which will expire at various dates through 2037. As of December 31, 2017, the Company had Federal and State research and development tax credit carryforwards of approximately $1.8 million and $299,000, respectively, which will expire at various dates through 2037. On December 22, 2017, the Tax Cuts and Jobs Act of 2017 (Tax Act) was enacted into law making significant changes to the Internal Revenue Code. The main provision impacting the Company is the reduction in the U.S. statutory corporate tax rate to 21% for years beginning after December 31, 2017. On the same day, the SEC staff issued Staff Accounting Bulletin No. 118, or SAB 118, which provides guidance for companies that have not completed their accounting for the income tax effects of the Tax Act in the period of enactment, allowing for a measurement period of up to one year after the enactment date to finalize the recording of the related tax impacts. Based on the reduction in the corporate tax rate, we revalued our deferred tax assets and liabilities which resulted in an $8.9 million reduction in the deferred tax asset and the corresponding valuation allowance as of December 31, 2017. The net impact of the change in tax rate was zero due to the Company’s full valuation allowance. Significant components of the Company’s deferred tax assets and liabilities at December 31, 2017 and 2016 are as follows: 12/31/2017 12/31/2016 Deferred Tax Assets Federal & State NOL carryforward $ 16,935,101 $ 16,669,295 Federal & State R&D credit carryforward 2,058,771 1,271,891 Intangibles – net 325,744 700,215 Accounts payable and accrued expenses 615,490 772,841 Stock options 2,197,983 2,399,666 Fixed assets – net 6,409 3,861 Gross deferred tax assets 22,139,498 21,817,769 Valuation Allowance (22,123,292 ) (21,786,477 ) Net Deferred Tax Assets 16,206 31,292 Deferred Tax Liabilities Note Discounts (16,206 ) (31,292 ) Gross deferred tax liabilities (16,206 ) (31,292 ) TOTAL $ — $ — The change in valuation allowance of $0.3 million from December 31, 2016 to December 31, 2017 is primarily driven by no tax benefit being recorded on the current year loss from operations offset by the impact of revaluing the Company’s deferred tax assets due to the Tax Act. Under Section 382 of the Internal Revenue Code of 1986, as amended (Code), a corporation that undergoes an “ownership change” is subject to limitations on its ability to utilize its pre-change “Built-In-Gain” All tax years are open for examination by the taxing authorities for both federal and state purposes. A reconciliation of the federal statutory tax rate of 34% to the Company’s effective income tax rates are as follows: Years ended 2017 2016 Statutory tax rate 34.00 % 34.00 % State taxes, net of federal benefits 5.37 % 5.24 % Federal research and development credits 3.00 % 2.84 % Change in valuation allowance (1.51 )% (39.42 )% Stock-based compensation (1.11 )% (2.63 )% Federal rate change (39.75 )% 0.00 % Other 0.00 % (0.03 )% Effective tax rate 0.00 % 0.00 % The Company accounts for uncertain tax positions pursuant to ASC 740 which prescribes a recognition threshold and measurement process for financial statement recognition of uncertain tax positions taken or expected to be taken in a tax return. If the tax position meets this threshold, the benefit to be recognized is measured as the tax benefit having the highest likelihood of being realized upon ultimate settlement with the taxing authority. The Company recognizes interest accrued related to unrecognized tax benefits and penalties in the provision for income taxes. Management is not aware of any uncertain tax positions.

Stock Incentive Plan

Stock Incentive Plan	12 Months Ended
	Dec. 31, 2017
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Stock Incentive Plan	9. STOCK INCENTIVE PLAN The Company has three incentive plans. One was adopted in 2004 (2004 Plan) and provided for the granting of stock options and restricted stock awards and generally prescribed a contractual term of seven years. The 2004 Plan terminated in August 2010. However, grants made under the 2004 Plan are still governed by that plan. As of December 31, 2017, options to purchase 23,954 shares of common stock at a weighted average exercise price of $3.24 per share remained outstanding under the 2004 Plan. The Company approved the 2010 Employee, Director and Consultant Equity Incentive Plan (2010 Plan) in September 2010 to replace the 2004 Plan. The 2010 Plan provided for the granting of stock options and restricted stock awards. The 2010 Plan terminated upon the Company’s initial public offering. However, grants made under the 2010 Plan are still governed by that plan. As of December 31, 2017, options to purchase 413,130 shares of common stock at a weighted average exercise price of $1.58 per share remained outstanding under the 2010 Plan. The Company approved the 2013 Equity Incentive Plan (2013 Plan) in October 2013 and amended the 2013 Plan in June 2016. The 2013 Plan provides for the granting of stock options, restricted stock, stock appreciation rights, stock units, and performance cash awards to certain employees, members of the board of directors and consultants of the Company. On January 1 of each year the aggregate number of common shares that may be issued under the 2013 Plan shall automatically increase by a number of shares equal to the least of (a) 7% of the total number of common shares outstanding on the last calendar day of the prior fiscal year, (b) subject to adjustment for certain corporate transactions, 1,000,000 common shares, or (c) a number of common shares determined by the Company’s board of directors. As of December 31, 2017, options to purchase 1,809,773 shares of common stock at a weighted average exercise price of $5.65 per share and restricted stock units of 157,128 remained outstanding under the 2013 Plan. As of December 31, 2017, there were 779,856 shares of common stock available for grant under the 2013 Plan. As of January 1, 2018, the number of shares of common stock that may be issued under the 2013 Plan was automatically increased by 1,000,000 shares, increasing the number of shares of common stock available for issuance under the 2013 Plan to 1,779,856. The Company recognizes stock-based compensation expense over the requisite service period. The Company’s share-based awards are accounted for as equity instruments. The amounts included in the consolidated statements of operations relating to stock-based compensation are as follows: Year ended December 31, 2017 2016 Research and development expenses $ 896,339 $ 1,167,142 General and administrative expenses 1,818,502 1,592,611 Total stock-based compensation expense $ 2,714,841 $ 2,759,753 Stock Options Terms of stock option agreements, including vesting requirements, are determined by the board of directors, subject to the provisions of the respective plan they were granted. Options granted by the Company typically vest over a four year period. Certain of the options are subject to acceleration of vesting in the event of certain change of control transactions. The options may be granted for a term of up to ten years from the date of grant. The exercise price for options granted under the 2013 Plan must be at a price no less than 100% of the fair market value of a common share on the date of grant. The following table summarizes option activity under the incentive plans for the years ended December 31, 2017 and 2016: Number of Weighted Weighted Aggregate Outstanding at December 31, 2016 1,498,585 $ 4.63 Granted 899,337 5.13 Cancelled/Forfeited (151,065 ) 4.02 Exercised — — Outstanding at December 31, 2017 2,246,857 $ 4.87 7.81 $ 4,683,444 Exercisable at December 31, 2017 1,176,178 $ 4.46 6.90 $ 3,029,015 (a) The aggregate intrinsic value in this table was calculated on the positive difference, if any, between the closing market value of the Company’s common stock on December 31, 2017 of $6.80 and the price of the underlying options. The Company records stock-based compensation related to stock options granted at fair value. During the years ended December 31, 2017 and 2016, the Company used the Black-Scholes option-pricing model to estimate the fair value of stock option grants and to determine the related compensation expense. The assumptions used in calculating the fair value of stock-based payment awards represent management’s best estimates. The weighted-average fair value of options granted was $3.76 and $5.43 for the years ended December 31, 2017 and 2016, respectively. The assumptions used in determining fair value of the employee stock options for the years ended December 2017 and 2016, are as follows: December 31, December 31, Expected dividend yield 0 % 0 % Anticipated volatility 76.52% - 88.57 % 88.57 % Stock price $4.90 - $6.10 $3.94 - $7.48 Exercise price $4.90 - $6.10 $3.94 - $7.48 Expected life (years) 5.50 - 6.25 5.50 - 6.25 Risk free interest rate 1.87% - 2.26 % 0.59% - 2.20 % The dividend yield of zero is based on the fact that the Company has never paid cash dividends and have no present intention to pay cash dividends. Expected volatility is estimated using both the historical volatility of the Company and the historical volatility from a group of similar companies The Company has estimated the expected life of our employee stock options using the “simplified” method, whereby, the expected life equals the average of the vesting term and the original contractual term of the option for service-based awards since the Company doesn’t have sufficient historical or implied data of its own. The risk-free interest rates for periods within the expected life of the option are based on the yields of zero-coupon At December 31, 2017, there is approximately $3.7 million of unrecognized compensation cost relating to stock options outstanding, which the Company expects to recognize over a weighted average period of 2.46 years. Total unrecognized compensation cost will be adjusted for future forfeitures, if necessary. Restricted Stock Units Terms of restricted stock unit (RSUs) agreements, including vesting requirements, are determined by the board of directors, subject to the provisions of the 2013 Plan. RSUs granted by the Company typically vest over a four year period. In the event that the employees’ employment with the Company terminates any unvested shares are forfeited and revert to the Company. Restricted stock units are not included in issued and outstanding common stock until the shares are vested and released. The table below summarizes activity relating to RSUs: Number Outstanding at December 31, 2016 27,096 Granted 136,806 Vested/released (6,774 ) Outstanding at December 31, 2017 157,128 The weighted-average fair value of RSUs granted was $5.10 and $6.33 per share for the years ended December 31, 2017 and 2016, respectively. As of December 31, 2017, the outstanding restricted stock units had unamortized stock-based compensation of $646,469 with a weighted-average remaining recognition period of 3.05 years and an aggregate intrinsic value of $1.1 million. Employee Stock Purchase Plan In March 2016, the Company’s board of directors approved the 2016 Employee Stock Purchase Plan (2016 ESPP), which became effective in June 2016 following the approval of the Company’s stockholders. The 2016 ESPP authorizes the initial issuance of up to a total of 97,500 shares of the Company’s common stock to participating employees. The number of shares reserved for issuance under the 2016 ESPP automatically increases on the first business day of each fiscal year, commencing in 2017, by a number equal to the lesser of (i) 1% of the shares of common stock outstanding on the last business day of the prior fiscal year; or (ii) the number of shares determined by the Company’s Board of Directors. On January 1, 2017, the number of shares authorized for issuance under the 2016 ESPP was automatically increased by 125,763 shares, increasing the number of shares of common stock authorized for issuance under the 2016 ESPP to 223,263. Unless otherwise determined by the administrator of the 2016 ESPP, two offering periods of six months’ duration will begin each year on January 1 and July 1. Participating employees purchase stock under the 2016 ESPP at a price equal to the lower of 85% of the closing price on the applicable offering commencement date or 85% of the closing price on the applicable offering termination date. The fair value of the purchase rights granted under this plan was estimated on the date of grant using the Black-Scholes option-pricing model using assumptions, which were derived in a manner similar to those discussed above relative to stock options. As of December 31, 2016, there was no activity under the 2016 ESPP. At December 31, 2017, the Company has 191,778 shares available for issuance under the 2016 ESPP. A summary of the weighted-average grant-date fair value, shares issued and total stock-based compensation expense recognized related to the Plan are as follows: Year ended Weighted-average grant-date fair value per share $ 2.03 Weighted-average price per share $ 3.98 Total shares issued 31,485 Total stock-based compensation expense $ 64,033

Stock Purchase Warrants

Stock Purchase Warrants	12 Months Ended
	Dec. 31, 2017
Text Block [Abstract]
Stock Purchase Warrants	10. STOCK PURCHASE WARRANTS As of December 31, 2017, there were 1,384,608 warrants to purchase shares of common stock of the Company outstanding with a weighted-average exercise price of $9.52 per share and weighted-average remaining life of 0.1 years. During the years ended December 31, 2017 and 2016, there were no exercises, issuances or expirations of warrants to purchase shares of common stock of the Company. Subsequent to December 31, 2017, there were 1,324,608 warrants to purchase shares of common stock of the Company that expired unexercised. A summary of the common share purchase warrants outstanding and exercisable at December 31, 2017 is as follows: Exercise Number Expiry Date $ 10.00 60,000 May 1, 2019 9.50 1,113,080 January 14, 2018 9.50 211,528 January 21, 2018 1,384,608

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2017
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	11. COMMITMENTS AND CONTINGENCIES Guarantees and Indemnifications Other Contractual Arrangements – In September 2017, the Company executed a Lease Agreement (the “Office Lease”), which was amended in November 2017. The amended lease as of December 31, 2017, consisted of approximately 9,351 square feet of office space of office space located in Lexington, Massachusetts (the “Premises”). The Company intends to use the Premises as our corporate headquarters. The term of the Office Lease is through December 31, 2020, or as extended under our option to extend in the Office Lease. The Office Lease provides for a monthly base rent of $13,559, commencing on December 1, 2017. In addition to the base rent, the Company is required to pay the landlord certain operating expenses, taxes and other fees in accordance with the terms of the Office Lease. Rent expense for the years ended December 31, 2017 and 2016 was $157,682 and $123,580, respectively. The Company’s gross future minimum payments under all non-cancelable Total 2018 2019 2020 2021 Operating lease obligations $ 669,263 $ 203,272 $ 228,320 $ 237,671 $ —

Subsequent Event

Subsequent Event	12 Months Ended
	Dec. 31, 2017
Subsequent Events [Abstract]
Subsequent Event	12. SUBSEQUENT EVENT In June 2017, the Company entered into a Controlled Equity Offering SM

Basis of Presentation and Sig21

Basis of Presentation and Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2017
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation
Risks and Uncertainties	Risks and Uncertainties The Company’s success will depend in part on its ability to obtain patents and product license rights, maintain trade secrets, and operate without infringing on the property rights of others, both in the United States and other countries. There can be no assurance that patents issued to or licensed by the Company will not be challenged, invalidated, circumvented, or that the rights granted thereunder will provide proprietary protection or competitive advantages to the Company. The Company believes that its cash, cash equivalents and marketable securities as of December 31, 2017, together with the proceeds from the Sales Agreement through March 29, 2018 and the amounts available under the Credit Facility, will be adequate to fund operations through the end of 2019 based on its current business plan. The Company will need to raise additional capital to implement its business plan. Additional funding may not be available to the Company on acceptable terms, or at all. If the Company is unable to secure additional capital, or meet financial covenants that could be implemented under the Company’s term loans in certain circumstances, it will be required to significantly decrease the amount of planned expenditures, and may be required to cease operations. Curtailment of operations would cause significant delays in the Company’s efforts to introduce its products to market, which is critical to the realization of its business plan and the future operations of the Company.
Use of Estimates	Use of Estimates
Segment Information	Segment Information
Cash and Cash Equivalents	Cash and Cash Equivalents RRAs are collateralized by deposits in the form of ‘Government Securities and Obligations’ for an amount not less than 102% of their value. The Company does not record an asset or liability related to the collateral as the Company is not permitted to sell or repledge the associated collateral. The Company has a policy that the collateral has at least an A (or equivalent) credit rating. The Company utilizes a third-party custodian to manage the exchange of funds and ensure that collateral received is maintained at 102% of the value of the RRAs on a daily basis. RRAs with original maturities of greater than three months are classified as marketable securities.
Marketable Securities	Marketable Securities available-for-sale re-evaluates
Fair Value of Financial Instruments	Fair Value of Financial Instruments
Concentration of Credit Risk	Concentration of Credit Risk to-date.
Intellectual Property	Intellectual Property
Income Taxes	Income Taxes Income Taxes The Company accounts for uncertain tax positions pursuant to ASC 740 which prescribes a recognition threshold and measurement process for financial statement recognition of uncertain tax positions taken or expected to be taken in a tax return. If the tax position meets this threshold, the benefit to be recognized is measured as the tax benefit having the highest likelihood of being realized upon ultimate settlement with the taxing authority. The Company recognizes interest accrued related to unrecognized tax benefits and penalties in the provision for income taxes. Management is not aware of any uncertain tax positions.
Research and Development Costs	Research and Development Costs Preclinical and clinical trial expenses relate to third-party services, subject-related fees at the sites where the Company’s clinical trials are being conducted, laboratory costs, analysis costs, toxicology studies and investigator fees. Costs associated with these expenses are generally payable on the passage of time or when certain milestones are achieved. Expense is recorded during the period incurred or in the period in which a milestone is achieved. In order to ensure that the Company has adequately provided for preclinical and clinical expenses during the proper period, the Company maintains an accrual to cover these expenses. These accruals are assessed on a quarterly basis and are based on such assumptions as expected total cost, the number of subjects and clinical trial sites and length of the study. Actual results may differ from these estimates and could have a material impact on the Company’s reported results. The Company’s historical accrual estimates have not been materially different from actual costs.
Stock-Based Compensation	Stock-Based Compensation Compensation – Stock Compensation Equity instruments issued to nonemployees are accounted for under the provisions of ASC 718 and ASC 505-50, Equity – Equity-Based Payments to Non-Employees From time to time the Company may grant awards with performance conditions necessary to be achieved in order to vest in the award. The Company records compensation expense for those awards over the vesting period of the award to the extent the performance conditions are deemed probable of achievement. From time to time the Company may grant awards with a market condition necessary to be achieved in order to vest in the award. The Company records compensation expense for those awards over the vesting period of the award on a straight-line basis utilizing Monte Carlo simulations to estimate the timing and number of shares that are most likely to vest.
Comprehensive Loss	Comprehensive Loss non-owner
Net Loss Per Share	Net Loss Per Share – Basic net loss per share available to common stockholders is calculated by dividing the net loss available to common stockholders by the weighted-average number of common shares outstanding during the period, without consideration for common stock equivalents. Diluted net loss per share available to common stockholders is computed by dividing the net loss available to common stockholders by the weighted-average number of common share equivalents outstanding for the period determined using the treasury-stock method. For purposes of this calculation, stock options, restricted stock units and common stock warrants are considered to be common stock equivalents and are only included in the calculation of diluted net loss per share available to common stockholders when their effect is dilutive.
Recent Accounting Pronouncements	Recent Accounting Pronouncements – In August 2016, the FASB issued Accounting Standards Update (ASU) No. 2016-15 (ASU 2016-15), Statement of Cash Flows ASU 2016-15 ASU 2016-15 In June 2016, the FASB issued ASU 2016-13, Financial Instrument-Credit Losses 2016-13). ASU 2016-13 ASU 2016-13 In March 2016, the FASB issued ASU No. 2016-09 Improvements to Employee Share-Based Payment Accounting 2016-09), 2016-09 In February 2016, the FASB issued ASU No. 2016-02 2016-02), Leases 2016-02 right-of-use ASU 2016-02 In January 2016, the FASB issued ASU No. 2016-01 , Recognition and Measurement of Financial Assets and Financial Liabilities 2016-01). 2016-01 2016-01 2016-01 In November 2015, the FASB issued ASU No. 2015-17 , Income Taxes 2015-17). 2015-17 tax-paying 2015-17. 2015-17 In April 2015, the FASB issued ASU No. 2015-03, Simplifying the Presentation of Debt Issuance Costs 2015-03). 2015-03 2015-03 In May 2014, the FASB issued ASU No. 2014-09, Revenue from Contracts with Customers Revenue Recognition ASU 2014-09

Net Loss Per Share (Tables)

Net Loss Per Share (Tables)	12 Months Ended
	Dec. 31, 2017
Earnings Per Share [Abstract]
Computation of Diluted Weighted-Average Shares Outstanding	The following potentially dilutive securities outstanding have been excluded from the computation of diluted weighted-average shares outstanding, because such securities had an antidilutive impact: Years ended December 31, 2017 2016 Options to purchase common stock 2,246,857 1,498,585 Warrants to purchase common stock 1,384,608 1,384,608 Restricted stock units 157,128 27,096 Total of common stock equivalents 3,788,593 2,910,289

Cash, Cash Equivalents and Ma23

Cash, Cash Equivalents and Marketable Securities (Tables)	12 Months Ended
	Dec. 31, 2017
Cash and Cash Equivalents [Abstract]
Schedule of Cash, Cash Equivalents and Marketable Securities	At December 31, 2017, cash, cash equivalents and marketable securities were comprised of: Carrying Unrecognized Unrecognized Estimated Fair Cash and Cash Current Cash $ 979,485 $ — $ — $ 979,485 $ 979,485 $ — Money market funds 1,043,852 — — 1,043,852 1,043,852 — U.S. reverse repurchase agreements 18,000,000 — — 18,000,000 18,000,000 — U.S. government agency securities 22,941,293 — (17,831 ) 22,923,462 — 22,923,462 Available for Sale(1) 40,941,293 — (17,831 ) 40,923,462 18,000,000 22,923,462 Total Cash, cash equivalents and current marketable securities $ 20,023,337 $ 22,923,462 (1) Available for sale securities are reported at fair value with unrealized gains and losses reported net of taxes, if material, in other comprehensive income.

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	12 Months Ended
	Dec. 31, 2017
Fair Value Disclosures [Abstract]
Schedule of Assets and Liabilities Measured at Fair Value on Recurring Basis	There were no liabilities measured at fair value at December 31, 2017 or 2016, respectively. December 31, 2017 Level 1 Level 2 Level 3 Total Assets: Money market funds(a) $ 1,043,852 $ — $ — $ 1,043,852 U.S. reverse repurchase agreements(b) — 18,000,000 — 18,000,000 U.S. government agency securities(b) — 22,923,462 — 22,923,462 Total assets at fair value $ 1,043,852 $ 40,923,462 $ — $ 41,967,314 December 31, 2016 Level 1 Level 2 Level 3 Total Assets: Money market funds(a) $ 70,212 $ — $ — $ 70,212 U.S. reverse repurchase agreements(b) — 11,550,000 — 11,550,000 U.S. government agency securities(b) — 12,897,584 — 12,897,584 Total assets at fair value $ 70,212 $ 24,447,584 $ — $ 24,517,796 (a) Money market funds included in cash and cash equivalents in the consolidated balance sheets, are valued at quoted market prices in active markets. (b) U.S. reverse repurchase agreements and U.S. government agency securities are recorded at fair market values, which are determined based on the most recent observable inputs for similar instruments in active markets or quoted prices for identical or similar instruments in markets that are not active or are directly or indirectly observable.

Accrued Expenses (Tables)

Accrued Expenses (Tables)	12 Months Ended
	Dec. 31, 2017
Payables and Accruals [Abstract]
Schedule of Accrued Expenses	Accrued expenses at December 31, 2017 and 2016 were: 2017 2016 Accrued compensation $ 788,570 $ 983,449 Accrued research and development 1,327,103 913,838 Accrued general & administrative 120,792 48,964 Accrued expenses $ 2,236,465 $ 1,946,251

Credit Facility (Tables)

Credit Facility (Tables)	12 Months Ended
	Dec. 31, 2017
Debt Disclosure [Abstract]
Schedule of Future Maturities of Existing Term Loans	Future maturities of the existing term loans under the Credit Facility as of December 31, 2017 are as follows: 2018 $ 116,319 2019 465,278 2020 465,278 2021 348,958 Total $ 1,395,833

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Components of Deferred Tax Assets and Liabilities	Significant components of the Company’s deferred tax assets and liabilities at December 31, 2017 and 2016 are as follows: 12/31/2017 12/31/2016 Deferred Tax Assets Federal & State NOL carryforward $ 16,935,101 $ 16,669,295 Federal & State R&D credit carryforward 2,058,771 1,271,891 Intangibles – net 325,744 700,215 Accounts payable and accrued expenses 615,490 772,841 Stock options 2,197,983 2,399,666 Fixed assets – net 6,409 3,861 Gross deferred tax assets 22,139,498 21,817,769 Valuation Allowance (22,123,292 ) (21,786,477 ) Net Deferred Tax Assets 16,206 31,292 Deferred Tax Liabilities Note Discounts (16,206 ) (31,292 ) Gross deferred tax liabilities (16,206 ) (31,292 ) TOTAL $ — $ —
Summary of Statutory Tax Rates and Effective Tax Rates	A reconciliation of the federal statutory tax rate of 34% to the Company’s effective income tax rates are as follows: Years ended 2017 2016 Statutory tax rate 34.00 % 34.00 % State taxes, net of federal benefits 5.37 % 5.24 % Federal research and development credits 3.00 % 2.84 % Change in valuation allowance (1.51 )% (39.42 )% Stock-based compensation (1.11 )% (2.63 )% Federal rate change (39.75 )% 0.00 % Other 0.00 % (0.03 )% Effective tax rate 0.00 % 0.00 %

Stock Incentive Plan (Tables)

Stock Incentive Plan (Tables)	12 Months Ended
	Dec. 31, 2017
Schedule of Stock-Based Compensation Expense	The amounts included in the consolidated statements of operations relating to stock-based compensation are as follows: Year ended December 31, 2017 2016 Research and development expenses $ 896,339 $ 1,167,142 General and administrative expenses 1,818,502 1,592,611 Total stock-based compensation expense $ 2,714,841 $ 2,759,753
Summary of Stock Option Activity	The following table summarizes option activity under the incentive plans for the years ended December 31, 2017 and 2016: Number of Weighted Weighted Aggregate Outstanding at December 31, 2016 1,498,585 $ 4.63 Granted 899,337 5.13 Cancelled/Forfeited (151,065 ) 4.02 Exercised — — Outstanding at December 31, 2017 2,246,857 $ 4.87 7.81 $ 4,683,444 Exercisable at December 31, 2017 1,176,178 $ 4.46 6.90 $ 3,029,015 (a) The aggregate intrinsic value in this table was calculated on the positive difference, if any, between the closing market value of the Company’s common stock on December 31, 2017 of $6.80 and the price of the underlying options.
Summary of Activity Relating to Restricted Stock Units	The table below summarizes activity relating to RSUs: Number Outstanding at December 31, 2016 27,096 Granted 136,806 Vested/released (6,774 ) Outstanding at December 31, 2017 157,128
Summary of Employee Stock Purchase Plan Activity	A summary of the weighted-average grant-date fair value, shares issued and total stock-based compensation expense recognized related to the Plan are as follows: Year ended Weighted-average grant-date fair value per share $ 2.03 Weighted-average price per share $ 3.98 Total shares issued 31,485 Total stock-based compensation expense $ 64,033
Employee Stock Options [Member]
Schedule of Fair Value of Stock Option Assumptions	The assumptions used in determining fair value of the employee stock options for the years ended December 2017 and 2016, are as follows: December 31, December 31, Expected dividend yield 0 % 0 % Anticipated volatility 76.52% - 88.57 % 88.57 % Stock price $4.90 - $6.10 $3.94 - $7.48 Exercise price $4.90 - $6.10 $3.94 - $7.48 Expected life (years) 5.50 - 6.25 5.50 - 6.25 Risk free interest rate 1.87% - 2.26 % 0.59% - 2.20 %

Stock Purchase Warrants (Tables

Stock Purchase Warrants (Tables)	12 Months Ended
	Dec. 31, 2017
Text Block [Abstract]
Summary of Common Share Purchase Warrants Outstanding and Exercisable	A summary of the common share purchase warrants outstanding and exercisable at December 31, 2017 is as follows: Exercise Number Expiry Date $ 10.00 60,000 May 1, 2019 9.50 1,113,080 January 14, 2018 9.50 211,528 January 21, 2018 1,384,608

Commitments and Contingencies (

Commitments and Contingencies (Tables)	12 Months Ended
	Dec. 31, 2017
Commitments and Contingencies Disclosure [Abstract]
Schedule of Future Minimum Payments Under Non-Cancelable Operating Leases	The Company’s gross future minimum payments under all non-cancelable Total 2018 2019 2020 2021 Operating lease obligations $ 669,263 $ 203,272 $ 228,320 $ 237,671 $ —

Basis of Presentation and Sig31

Basis of Presentation and Significant Accounting Policies - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2017USD ($)Segment	Dec. 31, 2016USD ($)
Class of Stock [Line Items]
Number of segment | Segment	1
Investment maturity period	Three months or less
Marketable securities maturity period	90 days
Net loss	$ (22,340,589)	$ (18,699,450)
Unrealized gain (loss) on marketable securities	$ (17,960)	8,490
Maximum [Member]
Class of Stock [Line Items]
Minimum maturity period	90 days
Minimum [Member]
Class of Stock [Line Items]
Percentage of investment in the form of government securities and obligations	102.00%
Intellectual Property [Member]
Class of Stock [Line Items]
Intellectual property related expenses	$ 768,000	$ 554,000

Net Loss Per Share - Computatio

Net Loss Per Share - Computation of Diluted Weighted-Average Shares Outstanding (Detail) - shares	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total of common stock equivalents	3,788,593	2,910,289
Employee Stock Options [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total of common stock equivalents	2,246,857	1,498,585
Warrant [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total of common stock equivalents	1,384,608	1,384,608
Restricted Stock Units (RSUs) [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total of common stock equivalents	157,128	27,096

Cash, Cash Equivalents and Ma33

Cash, Cash Equivalents and Marketable Securities - Schedule of Cash, Cash Equivalents and Marketable Securities (Detail) - USD ($)	Dec. 31, 2017	Dec. 31, 2016	Jan. 01, 2016
Cash Cash Equivalents And Marketable Securities [Line Items]
Cash	$ 979,485
Money market funds	1,043,852
U.S. reverse repurchase agreements	18,000,000
U.S. government agency securities	22,941,293
Available for Sale	40,941,293
Unrecognized Gain	0
Cash and cash equivalents	20,023,337	$ 12,015,061	$ 14,648,866
Current Marketable Securities	22,923,462	$ 12,897,584
Available for Sale [Member]
Cash Cash Equivalents And Marketable Securities [Line Items]
Unrecognized Gain	0
Unrecognized Loss	(17,831)
Estimated Fair Value	40,923,462
Cash and cash equivalents	18,000,000
Current Marketable Securities	22,923,462
Cash [Member]
Cash Cash Equivalents And Marketable Securities [Line Items]
Unrecognized Gain	0
Estimated Fair Value	979,485
Cash and cash equivalents	979,485
Money Market Funds [Member]
Cash Cash Equivalents And Marketable Securities [Line Items]
Unrecognized Gain	0
Estimated Fair Value	1,043,852
Cash and cash equivalents	1,043,852
U.S. Reverse Repurchase Agreements [Member]
Cash Cash Equivalents And Marketable Securities [Line Items]
Unrecognized Gain	0
Estimated Fair Value	18,000,000
Cash and cash equivalents	18,000,000
US Government Agencies Securities [Member]
Cash Cash Equivalents And Marketable Securities [Line Items]
Unrecognized Gain	0
Unrecognized Loss	(17,831)
Estimated Fair Value	22,923,462
Current Marketable Securities	$ 22,923,462

Cash, Cash Equivalents and Ma34

Cash, Cash Equivalents and Marketable Securities - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2017
Maximum [Member]
Cash Cash Equivalents And Marketable Securities [Line Items]
Contractual maturities of available for sale securities	1 year

Fair Value Measurements - Addit

Fair Value Measurements - Additional Information (Detail) - USD ($)	Dec. 31, 2017	Dec. 31, 2016
Fair Value Disclosures [Abstract]
Liabilities measured at fair value on a recurring basis	$ 0	$ 0

Fair Value Measurements - Sched

Fair Value Measurements - Schedule of Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) - USD ($)		Dec. 31, 2017	Dec. 31, 2016
Assets:
Total assets at fair value		$ 41,967,314	$ 24,517,796
Money Market Funds [Member]
Assets:
Total assets at fair value	[1]	1,043,852	70,212
U.S. Reverse Repurchase Agreements [Member]
Assets:
Total assets at fair value	[2]	18,000,000	11,550,000
US Government Agencies Securities [Member]
Assets:
Total assets at fair value	[2]	22,923,462	12,897,584
Level 1 [Member]
Assets:
Total assets at fair value		1,043,852	70,212
Level 1 [Member] | Money Market Funds [Member]
Assets:
Total assets at fair value	[1]	1,043,852	70,212
Level 2 [Member]
Assets:
Total assets at fair value		40,923,462	24,447,584
Level 2 [Member] | U.S. Reverse Repurchase Agreements [Member]
Assets:
Total assets at fair value	[2]	18,000,000	11,550,000
Level 2 [Member] | US Government Agencies Securities [Member]
Assets:
Total assets at fair value	[2]	$ 22,923,462	$ 12,897,584
[1]	Money market funds included in cash and cash equivalents in the consolidated balance sheets, are valued at quoted market prices in active markets.
[2]	U.S. reverse repurchase agreements and U.S. government agency securities are recorded at fair market values, which are determined based on the most recent observable inputs for similar instruments in active markets or quoted prices for identical or similar instruments in markets that are not active or are directly or indirectly observable.

Accrued Expenses - Schedule of

Accrued Expenses - Schedule of Accrued Expenses (Detail) - USD ($)	Dec. 31, 2017	Dec. 31, 2016
Payables and Accruals [Abstract]
Accrued compensation	$ 788,570	$ 983,449
Accrued research and development	1,327,103	913,838
Accrued general & administrative	120,792	48,964
Accrued expenses	$ 2,236,465	$ 1,946,251

Credit Facility - Additional In

Credit Facility - Additional Information (Detail) - USD ($)	1 Months Ended	12 Months Ended
	Nov. 30, 2013	Dec. 31, 2017	Dec. 31, 2016	Apr. 12, 2012
Line of Credit Facility [Line Items]
Exercise price of warrants per share		$ 9.52
Warrant value	$ 178,000
Warrant liability				$ 88,000
Series B Preferred Stock [Member]
Line of Credit Facility [Line Items]
Warrant exercisable	9,692
Exercise price of warrants per share	$ 5.16
Warrant exercisable, term	7 years
Pacific Western Bank [Member]
Line of Credit Facility [Line Items]
Proceeds from credit facility		$ 2,000,000
Debt instrument annual interest rate		5.25%
Credit facility outstanding		$ 1,400,000
Loan repayment period		36 months
Pacific Western Credit Facility [Member]
Line of Credit Facility [Line Items]
Net of debt discount amount		$ 59,000	$ 80,000
Term Loan [Member] | Pacific Western Bank [Member]
Line of Credit Facility [Line Items]
Credit facility amount		$ 5,000,000
Term Loan [Member] | Pacific Western Bank [Member] | Prime Rate [Member]
Line of Credit Facility [Line Items]
Debt instrument variable annual interest rate		2.00%
Tranche B Loans [Member] | Pacific Western Bank [Member]
Line of Credit Facility [Line Items]
Proceeds from credit facility		$ 3,000,000

Credit Facility - Schedule of F

Credit Facility - Schedule of Future Maturities of Existing Term Loans (Detail)	Dec. 31, 2017USD ($)
Line of Credit Facility [Abstract]
2,018	$ 116,319
2,019	465,278
2,020	465,278
2,021	348,958
Total	$ 1,395,833

Income Taxes - Additional Infor

Income Taxes - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Income Tax Contingency [Line Items]
Provision for income tax benefit		$ 0
Deferred tax assets valuation allowance		100.00%
Net operating loss carryforwards expire period		2,037
Increasing in research activities expire period		2,037
Statutory tax rate		34.00%	34.00%
Tax cuts and jobs act of 2017 change in tax rate deferred tax assets decrease in valuation allowance		$ 8,900,000
Tax cuts and jobs act of 2017 change in tax rate decrease in deferred tax assets		8,900,000
Change in valuation allowance		300,000
Scenario, Plan [Member]
Income Tax Contingency [Line Items]
Statutory tax rate	21.00%
Federal [Member]
Income Tax Contingency [Line Items]
Net operating loss carryforwards		62,800,000
Increasing in research activities		1,800,000
State [Member]
Income Tax Contingency [Line Items]
Net operating loss carryforwards		59,400,000
Increasing in research activities		$ 299,000

Income Taxes - Components of De

Income Taxes - Components of Deferred Tax Assets and Liabilities (Detail) - USD ($)	Dec. 31, 2017	Dec. 31, 2016
Deferred Tax Assets
Federal & State NOL carryforward	$ 16,935,101	$ 16,669,295
Federal & State R&D credit carryforward	2,058,771	1,271,891
Intangibles - net	325,744	700,215
Accounts payable and accrued expenses	615,490	772,841
Stock options	2,197,983	2,399,666
Fixed assets - net	6,409	3,861
Gross deferred tax assets	22,139,498	21,817,769
Valuation Allowance	(22,123,292)	(21,786,477)
Net Deferred Tax Assets	16,206	31,292
Deferred Tax Liabilities
Note Discounts	(16,206)	(31,292)
Gross deferred tax liabilities	(16,206)	(31,292)
TOTAL	$ 0	$ 0

Income Taxes - Summary of Statu

Income Taxes - Summary of Statutory Tax Rates and Effective Tax Rates (Detail)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Income Tax Disclosure [Abstract]
Statutory tax rate	34.00%	34.00%
State taxes, net of federal benefits	5.37%	5.24%
Federal research and development credits	3.00%	2.84%
Change in valuation allowance	(1.51%)	(39.42%)
Stock-based compensation	(1.11%)	(2.63%)
Federal rate change	(39.75%)	0.00%
Other	(0.00%)	(0.03%)
Effective tax rate	0.00%	0.00%

Stock Incentive Plan - Addition

Stock Incentive Plan - Additional Information (Detail)	Jan. 01, 2018shares	Jan. 01, 2017shares	Jan. 01, 2016shares	Mar. 31, 2016shares	Dec. 31, 2017USD ($)Incentive_Plan$ / sharesshares	Dec. 31, 2016$ / sharesshares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of incentive plans | Incentive_Plan					3
Options to purchase of shares of common stock					2,246,857	1,498,585
Exercise price per share of common stock | $ / shares					$ 4.87	$ 4.63
Weighted average grant date fair value | $ / shares					$ 3.76	5.43
Unamortized stock-based compensation | $					$ 3,700,000
Weighted average recognition period					2 years 5 months 16 days
Employee Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair value of a common stock percentage					100.00%
Share based compensation, vesting period					4 years
Employee Stock Options [Member] | Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options granted in term years					10 years
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based compensation, vesting period					4 years
Unamortized stock-based compensation | $					$ 646,469
Weighted average grant date fair value of shares | $ / shares					$ 5.10	$ 6.33
Weighted average remaining recognition period					3 years 18 days
Aggregate intrinsic value of options outstanding | $					$ 1,100,000
2004 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock incentive plans, contractual term					Seven years
Stock incentive plan, termination date					2010-08
Options to purchase of shares of common stock					23,954
Exercise price per share of common stock | $ / shares					$ 3.24
2010 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options to purchase of shares of common stock					413,130
Exercise price per share of common stock | $ / shares					$ 1.58
2013 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options to purchase of shares of common stock					1,809,773
Exercise price per share of common stock | $ / shares					$ 5.65
Percentage of increase in common shares outstanding			7.00%
Increase in common stock outstanding			1,000,000
Number of restricted stock units outstanding					157,128
Common stock available for issuance					779,856
2013 Plan [Member] | Subsequent Event [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock available for issuance	1,779,856
Common stock issued	1,000,000
2016 Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock available for issuance					191,778
Common stock issued		125,763
Weighted average grant date fair value | $ / shares					$ 2.03
Issuance of common stock authorized		223,263		97,500
Percentage increase in number of shares of common stock reserved for issuance				1.00%
Share-based compensation arrangement by share-based payment award, closing price on the applicable offering commencement					85.00%
Share-based compensation arrangement by share-based payment award, closing price on the applicable offering termination date					85.00%
Share-based compensation arrangement by share-based payment award, description					In March 2016, the Company’s board of directors approved the 2016 Employee Stock Purchase Plan (2016 ESPP), which became effective in June 2016 following the approval of the Company’s stockholders. The 2016 ESPP authorizes the initial issuance of up to a total of 97,500 shares of the Company’s common stock to participating employees. The number of shares reserved for issuance under the 2016 ESPP automatically increases on the first business day of each fiscal year, commencing in 2017, by a number equal to the lesser of (i) 1% of the shares of common stock outstanding on the last business day of the prior fiscal year; or (ii) the number of shares determined by the Company’s Board of Directors. On January 1, 2017, the number of shares authorized for issuance under the 2016 ESPP was automatically increased by 125,763 shares, increasing the number of shares of common stock authorized for issuance under the 2016 ESPP to 223,263. Unless otherwise determined by the administrator of the 2016 ESPP, two offering periods of six months’ duration will begin each year on January 1 and July 1. Participating employees purchase stock under the 2016 ESPP at a price equal to the lower of 85% of the closing price on the applicable offering commencement date or 85% of the closing price on the applicable offering termination date.

Stock Incentive Plan - Schedule

Stock Incentive Plan - Schedule of Stock-Based Compensation Expense (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total stock-based compensation expense	$ 2,714,841	$ 2,759,753
Research and Development Expenses [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total stock-based compensation expense	896,339	1,167,142
General and Administrative Expenses [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total stock-based compensation expense	$ 1,818,502	$ 1,592,611

Stock Incentive Plan - Summary

Stock Incentive Plan - Summary of Stock Option Activity (Detail)	12 Months Ended
	Dec. 31, 2017USD ($)$ / sharesshares
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Number of Shares Outstanding, Beginning Balance | shares	1,498,585
Number of Shares, Granted | shares	899,337
Number of Shares,Cancelled/Forfeited | shares	(151,065)
Number of Shares, Exercised | shares	0
Number of Shares Outstanding, Ending Balance | shares	2,246,857
Number of Shares Exercisable, Ending Balance | shares	1,176,178
Weighted Average Exercise Price, Beginning Balance | $ / shares	$ 4.63
Weighted Average Exercise Price, Granted | $ / shares	5.13
Weighted Average Exercise Price, Cancelled/Forfeited | $ / shares	4.02
Weighted Average Exercise Price, Exercised | $ / shares	0
Weighted Average Exercise Price, Ending Balance | $ / shares	4.87
Weighted Average Exercise Price Exercisable, Ending Balance | $ / shares	$ 4.46
Weighted Average Contractual Term, Outstanding	7 years 9 months 22 days
Weighted Average Contractual Term, Exercisable	6 years 10 months 25 days
Aggregate Intrinsic Value, Outstanding | $	$ 4,683,444
Aggregate Intrinsic Value, Exercisable | $	$ 3,029,015

Stock Incentive Plan - Summar46

Stock Incentive Plan - Summary of Stock Option Activity (Parenthetical) (Detail)	Dec. 31, 2017$ / shares
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Closing market value of common stock	$ 6.80

Stock Incentive Plan - Schedu47

Stock Incentive Plan - Schedule of Fair Value of Stock Option Assumptions (Detail) - $ / shares	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock price	$ 6.80
Employee Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected dividend yield	0.00%	0.00%
Anticipated volatility		88.57%
Employee Stock Options [Member] | Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Anticipated volatility	76.52%
Stock price	$ 4.90	$ 3.94
Exercise price	$ 4.90	$ 3.94
Expected life (years)	5 years 6 months	5 years 6 months
Risk free interest rate	1.87%	0.59%
Employee Stock Options [Member] | Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Anticipated volatility	88.57%
Stock price	$ 6.10	$ 7.48
Exercise price	$ 6.10	$ 7.48
Expected life (years)	6 years 2 months 30 days	6 years 2 months 30 days
Risk free interest rate	2.26%	2.20%

Stock Incentive Plan - Summar48

Stock Incentive Plan - Summary of Activity Relating to Restricted Stock Units (Detail) - Restricted Stock Units (RSUs) [Member]	12 Months Ended
	Dec. 31, 2017shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Shares Outstanding, Beginning Balance	27,096
Number of Shares, Granted	136,806
Number of Shares, Vested/released	(6,774)
Number of Shares Outstanding, Ending Balance	157,128

Stock Incentive Plan - Summar49

Stock Incentive Plan - Summary of Employee Stock Purchase Plan Activity (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Employee Stock Purchase Plan [Line Items]
Weighted-average grant-date fair value per share	$ 3.76	$ 5.43
Total stock-based compensation expense	$ 2,714,841	$ 2,759,753
2016 Employee Stock Purchase Plan [Member]
Employee Stock Purchase Plan [Line Items]
Weighted-average grant-date fair value per share	$ 2.03
Weighted-average price per share	$ 3.98
Total shares issued	31,485
Total stock-based compensation expense	$ 64,033

Stock Purchase Warrants - Addit

Stock Purchase Warrants - Additional Information (Detail) - USD ($)	Jan. 01, 2018	Dec. 31, 2017	Dec. 31, 2016
Class of Warrant or Right [Line Items]
Warrants to Purchase shares of Common Stock		1,384,608
Weighted Average Exercise Price, per share		$ 9.52
Weighted Average Remaining Life		1 month 6 days
Class of warrants excercised		$ 0	$ 0
Class of warrants issued and expired		0	0
Subsequent Event [Member]
Class of Warrant or Right [Line Items]
Class of warrants issued and expired unexercised	1,324,608

Stock Purchase Warrants - Summa

Stock Purchase Warrants - Summary of Common Share Purchase Warrants Outstanding and Exercisable (Detail)	12 Months Ended
	Dec. 31, 2017$ / sharesshares
Class of Warrant or Right [Line Items]
Exercise Price | $ / shares	$ 9.52
Number Outstanding | shares	1,384,608
Exercise Price One [Member]
Class of Warrant or Right [Line Items]
Exercise Price | $ / shares	$ 10
Number Outstanding | shares	60,000
Expiry Date	May 1, 2019
Exercise Price Two [Member]
Class of Warrant or Right [Line Items]
Exercise Price | $ / shares	$ 9.50
Number Outstanding | shares	1,113,080
Expiry Date	Jan. 14, 2018
Exercise Price Three [Member]
Class of Warrant or Right [Line Items]
Exercise Price | $ / shares	$ 9.50
Number Outstanding | shares	211,528
Expiry Date	Jan. 21, 2018

Commitments and Contingencies -

Commitments and Contingencies - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2017USD ($)ft²	Dec. 31, 2016USD ($)
Commitments And Contingencies [Line Items]
Outstanding material claims	$ 0
Reserve for indemnification	0
Rent expense	$ 157,682	$ 123,580
Amendment [Member]
Commitments And Contingencies [Line Items]
Lease agreement area of office space | ft²	9,351
Initial base annual rent	$ 13,559
Lessee operating lease option to extend	The term of the Office Lease is through December 31, 2020, or as extended under our option to extend in the Office Lease.

Commitments and Contingencies53

Commitments and Contingencies - Schedule of Future Minimum Payments Under Non-Cancelable Operating Leases (Detail)	Dec. 31, 2017USD ($)
Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract]
Operating lease obligations, Total	$ 669,263
Operating lease obligations, 2018	203,272
Operating lease obligations, 2019	228,320
Operating lease obligations, 2020	237,671
Operating lease obligations, 2021	$ 0

Subsequent Event - Additional I

Subsequent Event - Additional Information (Detail) - USD ($)	1 Months Ended	3 Months Ended	12 Months Ended
	Jun. 30, 2017	Mar. 29, 2018	Dec. 31, 2017	Dec. 31, 2016
Subsequent Event [Line Items]
Common stock par value			$ 0.001	$ 0.001
Proceeds from public offering net of underwriting discounts, commissions and offering expenses			$ 37,469,611	$ 12,649,859
At The Market Facility [Member] | Cantor Fitzgerald And Co [Member]
Subsequent Event [Line Items]
Common stock par value	$ 0.001
Broker commission as percentage of sale proceed	3.00%
At The Market Facility [Member] | Cantor Fitzgerald And Co [Member] | Subsequent Event [Member]
Subsequent Event [Line Items]
Shares issued during public offering		527,000
Proceeds from public offering net of underwriting discounts, commissions and offering expenses		$ 4,100,000
At The Market Facility [Member] | Cantor Fitzgerald And Co [Member] | Maximum [Member]
Subsequent Event [Line Items]
Expected aggregate gross proceeds from issuance of stock	$ 20,000,000