Aldeyra Therapeutics (ALDX) 10-Q 28 Oct 21 2021 Q3 Quarterly report Financial data

Document And Entity Information

Document And Entity Information - shares	9 Months Ended
	Sep. 30, 2021	Oct. 26, 2021
Cover [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Sep. 30, 2021
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	Q3
Trading Symbol	ALDX
Entity Registrant Name	ALDEYRA THERAPEUTICS, INC.
Entity Central Index Key	0001341235
Current Fiscal Year End Date	--12-31
Entity Filer Category	Non-accelerated Filer
Entity Emerging Growth Company	false
Entity Small Business	true
Entity Common Stock, Shares Outstanding		58,092,105
Entity Current Reporting Status	Yes
Entity Shell Company	false
Title of 12(b) Security	Common Stock, $0.001 par value per share
Security Exchange Name	NASDAQ
Entity Interactive Data Current	Yes
Entity File Number	001-36332
Entity Tax Identification Number	20-1968197
Entity Address, Address Line One	131 Hartwell Avenue
Entity Address, Address Line Two	Suite 320
Entity Address, City or Town	Lexington
Entity Address, State or Province	MA
Entity Address, Postal Zip Code	02421
City Area Code	781
Local Phone Number	761-4904
Document Quarterly Report	true
Document Transition Report	false
Entity Incorporation, State or Country Code	DE

Consolidated Balance Sheets (Un

Consolidated Balance Sheets (Unaudited) - USD ($)	Sep. 30, 2021	Dec. 31, 2020
Current assets:
Cash and cash equivalents	$ 116,368,688	$ 52,858,311
Cash equivalent - reverse repurchase agreements	125,000,000	25,000,000
Prepaid expenses and other current assets	5,403,261	5,200,957
Total current assets	246,771,949	83,059,268
Right-of-use assets	406,014	233,310
Fixed assets, net	39,607	59,925
Total assets	247,217,570	83,352,503
Current liabilities:
Accounts payable	467,932	381,638
Accrued expenses	11,252,075	8,134,765
Current portion of credit facility	0	3,659,776
Current portion of operating lease liabilities	222,158	233,310
Total current liabilities	11,942,165	12,409,489
Operating lease liabilities, long-term	184,599	0
Long-term debt	15,420,904	11,434,456
Total liabilities	27,547,668	23,843,945
Commitments and contingencies (Notes 14 and 15)
Stockholders' equity:
Common stock, voting, $0.001 par value; 150,000,000 authorized and 58,045,432 and 38,667,491 shares issued and outstanding, respectively	58,045	38,667
Additional paid-in capital	498,549,312	296,385,619
Accumulated other comprehensive income	0	0
Accumulated deficit	(278,937,455)	(236,915,728)
Total stockholders’ equity	219,669,902	59,508,558
Total liabilities and stockholders’ equity	$ 247,217,570	$ 83,352,503

Consolidated Balance Sheets (_2

Consolidated Balance Sheets (Unaudited) (Parenthetical) - $ / shares	Sep. 30, 2021	Dec. 31, 2020
Statement Of Financial Position [Abstract]
Common stock, par value	$ 0.001	$ 0.001
Common stock, shares authorized	150,000,000	150,000,000
Common stock, shares issued	58,045,432	58,045,432
Common stock, shares outstanding	38,667,491	38,667,491

Consolidated Statements of Oper

Consolidated Statements of Operations (Unaudited) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Operating expenses:
Research and development	$ 12,894,344	$ 6,133,580	$ 32,095,132	$ 17,653,058
General and administrative	2,546,807	2,255,617	8,720,161	7,480,461
Loss from operations	(15,441,151)	(8,389,197)	(40,815,293)	(25,133,519)
Other income (expense):
Interest income	59,306	5,215	122,732	287,025
Interest expense	(413,110)	(489,191)	(1,329,166)	(1,415,055)
Total other income (expense), net	(353,804)	(483,976)	(1,206,434)	(1,128,030)
Net loss	$ (15,794,955)	$ (8,873,173)	$ (42,021,727)	$ (26,261,549)
Net loss per share - basic and diluted	$ (0.27)	$ (0.23)	$ (0.80)	$ (0.81)
Weighted average common shares outstanding - basic and diluted	58,019,099	37,796,946	52,688,846	32,395,217

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Loss (Unaudited) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Statement Of Income And Comprehensive Income [Abstract]
Net loss	$ (15,794,955)	$ (8,873,173)	$ (42,021,727)	$ (26,261,549)
Other comprehensive loss:
Unrealized loss on marketable securities, net of tax	0	(4,754)	0	(5,866)
Total other comprehensive loss	0	(4,754)	0	(5,866)
Comprehensive loss	$ (15,794,955)	$ (8,877,927)	$ (42,021,727)	$ (26,267,415)

Consolidated Statements of Stoc

Consolidated Statements of Stockholders' Equity (Unaudited) - USD ($)	Total	Helio Vision Inc [Member]	Common Voting Stock [Member]	Common Voting Stock [Member]Founders [Member]	Common Voting Stock [Member]Helio Vision Inc [Member]	Additional Paid-in Capital [Member]	Additional Paid-in Capital [Member]Founders [Member]	Additional Paid-in Capital [Member]Helio Vision Inc [Member]	Accumulated Other Comprehensive Income/(Loss), Net of Tax [Member]	Accumulated Deficit [Member]
Beginning Balance at Dec. 31, 2019	$ 48,082,317		$ 28,657			$ 247,409,793			$ 5,866	$ (199,361,999)
Beginning Balance, Shares at Dec. 31, 2019			28,656,832
Stock-based compensation	5,453,520					5,453,520
Issuance of common stock, acquisition of Helio Vision, Inc.				$ 238			$ (238)
Issuance of common stock, acquisition of Helio Vision, Inc., Shares				237,834
Issuance of common stock, net of issuance costs	40,716,543		$ 9,352			40,707,191
Issuance of common stock, net of issuance costs, Shares			9,351,749
Issuance of common stock, exercise of stock options	1,058,516		$ 219			1,058,297
Issuance of common stock, exercise of stock options, Shares			219,244
Issuance of common stock, employee stock purchase plan	126,966		$ 30			126,936
Issuance of common stock, employee stock purchase plan, Shares			30,254
Issuance of common stock, vested restricted stock awards			$ 136			(136)
Issuance of common stock, vested restricted stock awards, Shares			135,796
Other comprehensive loss	(5,866)								(5,866)
Net loss	(26,261,549)									(26,261,549)
Ending Balance at Sep. 30, 2020	69,170,447		$ 38,632			294,755,363			0	(225,623,548)
Ending Balance, Shares at Sep. 30, 2020			38,631,709
Beginning Balance at Jun. 30, 2020	52,789,666		$ 32,997			269,502,290			4,754	(216,750,375)
Beginning Balance, Shares at Jun. 30, 2020			32,997,346
Stock-based compensation	1,757,479					1,757,479
Issuance of common stock, acquisition of Helio Vision, Inc.				$ 36			(36)
Issuance of common stock, acquisition of Helio Vision, Inc., Shares				35,783
Issuance of common stock, net of issuance costs	22,446,055		$ 5,378			22,440,677
Issuance of common stock, net of issuance costs, Shares			5,377,681
Issuance of common stock, exercise of stock options	998,097		$ 205			997,892
Issuance of common stock, exercise of stock options, Shares			204,796
Issuance of common stock, vested restricted stock awards	57,077		$ 16			57,061
Issuance of common stock, vested restricted stock awards, Shares			16,103
Other comprehensive loss	(4,754)								(4,754)
Net loss	(8,873,173)									(8,873,173)
Ending Balance at Sep. 30, 2020	69,170,447		$ 38,632			294,755,363			$ 0	(225,623,548)
Ending Balance, Shares at Sep. 30, 2020			38,631,709
Beginning Balance at Dec. 31, 2020	59,508,558		$ 38,667			296,385,619				(236,915,728)
Beginning Balance, Shares at Dec. 31, 2020			38,667,491
Stock-based compensation	5,186,689					5,186,689
Issuance of common stock, acquisition of Helio Vision, Inc.		$ 2,499,991		$ 106	$ 247		(106)	$ 2,499,744
Issuance of common stock, acquisition of Helio Vision, Inc., Shares				106,182	246,562
Issuance of common stock, net of issuance costs	189,811,611		$ 18,092			189,793,519
Issuance of common stock, net of issuance costs, Shares			18,091,947
Issuance of common stock, exercise of stock options	$ 4,623,251		$ 634			4,622,617
Issuance of common stock, exercise of stock options, Shares	634,214		634,214
Issuance of common stock, employee stock purchase plan	$ 61,529		$ 12			61,517
Issuance of common stock, employee stock purchase plan, Shares			12,092
Issuance of common stock, vested restricted stock awards			$ 287			(287)
Issuance of common stock, vested restricted stock awards, Shares			286,944
Net loss	(42,021,727)									(42,021,727)
Ending Balance at Sep. 30, 2021	219,669,902		$ 58,045			498,549,312				(278,937,455)
Ending Balance, Shares at Sep. 30, 2021			58,045,432
Beginning Balance at Jun. 30, 2021	233,679,945		$ 57,997			496,764,448				(263,142,500)
Beginning Balance, Shares at Jun. 30, 2021			57,997,345
Stock-based compensation	1,721,134					1,721,134
Issuance of common stock, acquisition of Helio Vision, Inc.				$ 36			$ (36)
Issuance of common stock, acquisition of Helio Vision, Inc., Shares				35,784
Issuance of common stock, exercise of stock options	12,124		$ 3			12,121
Issuance of common stock, exercise of stock options, Shares			2,997
Issuance of common stock, employee stock purchase plan	51,654		$ 9			51,645
Issuance of common stock, employee stock purchase plan, Shares			9,306
Net loss	(15,794,955)									(15,794,955)
Ending Balance at Sep. 30, 2021	$ 219,669,902		$ 58,045			$ 498,549,312				$ (278,937,455)
Ending Balance, Shares at Sep. 30, 2021			58,045,432

Consolidated Statements of Cash

Consolidated Statements of Cash Flows (Unaudited) - USD ($)	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020
CASH FLOWS FROM OPERATING ACTIVITIES:
Net loss	$ (42,021,727)	$ (26,261,549)
Adjustments to reconcile net loss to net cash used in operating activities:
Stock-based compensation	6,123,554	5,453,520
Non-cash interest expense	326,672	424,516
Net amortization of premium on debt securities available for sale	0	(91,231)
Depreciation and amortization expense	202,909	217,806
Change in assets and liabilities:
Prepaid expenses and other current assets	(202,304)	(212,823)
Accounts payable	86,294	(684,402)
Accrued Expenses and other liabilities	4,506,394	(8,022,095)
Net cash used in operating activities	(30,978,208)	(29,176,258)
CASH FLOWS FROM INVESTING ACTIVITIES:
Acquisitions of fixed assets	(7,806)	0
Purchases of marketable securities	0	(5,776,090)
Sales and maturities of marketable securities	0	34,800,000
Net cash (used in) provided by investing activities	(7,806)	29,023,910
CASH FLOWS FROM FINANCING ACTIVITIES:
Proceeds from issuance of common stock, net of issuance costs	189,811,611	40,716,543
Proceeds from exercise of stock options	4,623,251	1,058,516
Proceeds from employee stock purchase plan	61,529	126,966
Net cash provided by financing activities	194,496,391	41,902,025
NET INCREASE IN CASH AND CASH EQUIVALENTS	163,510,377	41,749,677
CASH AND CASH EQUIVALENTS, BEGINNING OF PERIOD	77,858,311	44,425,830
CASH AND CASH EQUIVALENTS, END OF PERIOD	241,368,688	86,175,507
SUPPLEMENTAL DISCLOSURES OF CASH FLOW INFORMATION:
Cash paid during the period for interest	1,011,000	1,042,708
SUPPLEMENTAL INFORMATION AND DISCLOSURES OF NONCASH ACTIVITIES:
Common stock issued in connection with Helio Vision, Inc. acquisition milestone	58,045
Helio Vision Inc [Member]
SUPPLEMENTAL INFORMATION AND DISCLOSURES OF NONCASH ACTIVITIES:
Common stock issued in connection with Helio Vision, Inc. acquisition milestone	$ 2,499,991	$ 0

Nature of Business

Nature of Business	9 Months Ended
	Sep. 30, 2021
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Nature of Business	1. NATURE OF BUSINESS Aldeyra Therapeutics, Inc., together with its wholly-owned subsidiaries (the “Company” or “Aldeyra”), a Delaware corporation, is a clinical-stage biotechnology company devoted to developing and commercializing next-generation medicines to improve the lives of patients with immune-mediated diseases. The Company’s principal activities to date include raising capital and research and development activities.

Basis of Presentation

Basis of Presentation	9 Months Ended
	Sep. 30, 2021
Accounting Policies [Abstract]
Basis of Presentation	2. BASIS OF PRESENTATION The accompanying interim condensed consolidated financial statements and related disclosures are unaudited and have been prepared in accordance with U.S. generally accepted accounting principles (“GAAP”) for interim financial information and the instructions to Form 10-Q and Regulation S-X. Accordingly, they do not include all the information and footnotes required by GAAP for complete financial statements and should be read in conjunction with the Company’s audited consolidated financial statements and related notes included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2020, which was filed with the Securities and Exchange Commission on March 11, 2021 (the “2020 Form 10-K”). The financial information as of September 30, 2021, and the three and nine months ended September 30, 2021 and 2020, respectively, is unaudited. In the opinion of management all adjustments, consisting only of normal recurring adjustments considered necessary for the fair presentation of financial position, results of operations, and cash flows at the dates and for the periods presented, have been included. The balance sheet data as of December 31, 2020 was derived from audited consolidated financial statements. The results of the Company’s operations for any interim periods are not necessarily indicative of the results that may be expected for any other interim period or for a full fiscal year. Based on its current operating plan, the Company believes that its cash and cash equivalents, as of September 30, 2021, will be sufficient to fund currently projected operating expenses through the end of 2023, including potential new drug application (“NDA”) submissions; initial commercialization of reproxalap, if approved; and continued early and late-stage development of our product candidates in ocular and systemic immune-mediated diseases . As a result of the COVID-19 pandemic, clinical site availability, staffing, and patient recruitment have been negatively affected and the timelines to complete the Company’s clinical trials may be delayed. The Company’s assessment of its liquidity and capital resources includes an estimate of the financial impacts of these changes. The Company will need to secure additional funding in the future, from one or more equity or debt financings, collaborations, or other sources, in order to carry out all of the Company’s planned research and development activities and regulatory activities; commercialize product candidates; or conduct any substantial, additional development requirements requested by the Food and Drug Administration ("FDA"). Additional funding may not be available to the Company on acceptable terms, or at all. If the Company is unable to secure additional capital, 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 develop and 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 The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions, including fair value estimates for investments that affect the reported amounts of assets and liabilities and the disclosure of contingent assets and liabilities at the date of the consolidated financial statements, and the reported amounts of expenses during the reporting periods. The Company’s management evaluates its estimates and assumptions on an ongoing basis. Management’s most significant estimates in the Company’s consolidated financial statements include, but are not limited to, estimates related to clinical trial accruals, estimates related to prepaid and accrued research and development costs, acquired in-process research and development (“IPR&D”) expense, contingent liabilities, and accounting for income taxes and related valuation allowance. Although these estimates and assumptions are based on the Company’s knowledge of current events and actions it may undertake in the future, actual results may ultimately materially differ from these estimates and assumptions. Summary of Significant Accounting Policies There were no changes to significant accounting policies during the nine months ended September 30, 2021, as compared to the those identified in the 2020 Form 10-K. Recent Accounting Pronouncements In June 2016, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) No. 2016-13, Financial Instruments—Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments (“ASU 2016-13”). ASU 2016-13 requires that credit losses be reported as an allowance using an expected losses model, representing the entity’s current estimate of credit losses expected to be incurred. The accounting guidance currently in effect is based on an incurred loss model. For available-for-sale debt securities with unrealized losses, this standard now requires allowances to be recorded instead of reducing the amortized cost of the investment. The amendments under ASU 2016-13 are effective for interim and annual fiscal periods beginning after December 15, 2022. The Company is continuing to evaluate the impact of ASU 2016-13 but does not expect the adoption of this ASU to have a material impact on its consolidated financial statements.

Helio Vision Acquisition

Helio Vision Acquisition	9 Months Ended
	Sep. 30, 2021
Business Combinations [Abstract]
Helio Vision Acquisition	3. Helio Vision Acquisition On January 28, 2019 (the “Closing Date”), the Company acquired Helio Vision, Inc. (“Helio”). As a result of the acquisition, the Company initially issued an aggregate of 1,160,444 shares of common stock to the former securityholders and an advisor of Helio. The founders of Helio were issued 568,627 shares and non-founders were issued 591,817 shares. The Helio founders’ shares are subject to vesting based on continued service to the Company over three years from the Closing Date, of which, 92 % are vested as of September 30, 2021 . The Company recognizes the expense associated with the founders’ restricted shares as research and development compensation expense on a straight-line basis as the shares vest over the three-year period. For the nine months ended September 30, 2021 and September 30, 2020, the Company recorded $ 0.9 million and $ 1.0 million of research and development compensation expense, respectively, for the founders’ restricted shares. In January 2021, pursuant to the terms of the acquisition agreement, the Company issued 246,562 shares of its common stock to the former securityholders of Helio (the "January Shares"). In addition, the Company, subject to the conditions of the acquisition agreement, is contingently obligated to make additional payments to the former securityholders of Helio as follows:(a) $ 10.0 million of common stock following approval by the FDA of a new drug approval application for the prevention and/or treatment of proliferative vitreoretinopathy or a substantially similar label prior to the 10th anniversary of the Closing Date; and (b) $ 2.5 million of common stock following FDA approval of a new drug application for an indication (other than proliferative vitreoretinopathy) prior to the 12th anniversary of the Closing Date (the shares of common stock issuable pursuant to the preceding clauses (a) and (b) are referred to herein as the “Milestone Shares”), provided that in no event shall the Company be obligated to issue more than an aggregate of 5,248,885 shares of common stock. Additionally, in the event of certain change of control or divestitures by the Company, certain former convertible noteholders of Helio will be entitled to a tax gross-up payment in an amount not to exceed $ 1.0 million. The Company determined that liability accounting is not required for the Milestone Shares under FASB ASC Topic 480, Distinguishing Liabilities from Equity (“ASC 480”). The Company also determined that the Milestone Shares meet the scope exception as a derivative under FASB ASC Topic 815, Derivatives and Hedging (“ASC 815”), from inception of the Milestone Shares through September 30, 2021. Accordingly, the Milestone Shares are evaluated under FASB ASC Topic 450, Contingencies (“ASC 450”) and the Company will record a liability related to the Milestone Shares if the milestones are achieved, and the obligation to make additional payment(s) becomes probable. At that time, the Company will record the cost of the Milestone Shares issued to the founders as compensation expense and to the Helio non-founders as IPR&D expense if there is no alternative future use. At December 31, 2020, the issuance of the January Shares was considered probable and $ 2.5 million was accrued as contingent consideration payable in stock and the Company recorded $ 1.8 million to IPR&D (the “Milestone IPR&D”), which included a $ 0.5 million income tax benefit, and $ 1.2 million of compensation expense related to these January Shares, which amounted to 246,562 shares and were issued during the quarter ended March 31, 2021. No other milestones related to the remaining Milestone Shares are probable of being achieved as of September 30, 2021 .

Net Loss Per Share

Net Loss Per Share	9 Months Ended
	Sep. 30, 2021
Earnings Per Share [Abstract]
Net Loss Per Share	4. NET LOSS PER SHARE As of September 30, 2021 and 2020, 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: Three and Nine Months Ended September 30, 2021 2020 Options to purchase common stock 4,562,870 4,889,685 Restricted stock units 501,254 929,817 Nonvested founder shares (1) 46,674 188,638 Total of common stock equivalents 5,110,798 6,008,140 (1) Represents 46,674 and 188,638 shares of common stock that are issued and outstanding but that were subject to future vesting based on service requirements at September 30, 2021 and 2020 , respectively, and are, accordingly, not included in stockholders’ equity.

Cash, Cash Equivalents and Mark

Cash, Cash Equivalents and Marketable Securities	9 Months Ended
	Sep. 30, 2021
Cash And Cash Equivalents [Abstract]
Cash, Cash Equivalents and Marketable Securities	5. CASH, CASH EQUIVALENTS AND MARKETABLE SECURITIES Cash and cash equivalents, were comprised of: September 30, 2021 Carrying Unrecognized Unrecognized Estimated Cash and Cash Cash $ 111,966,754 $ — $ — $ 111,966,754 $ 111,966,754 Money market funds 4,401,934 — — 4,401,934 4,401,934 Reverse repurchase agreements 125,000,000 — — 125,000,000 125,000,000 Total Cash and cash equivalents $ 241,368,688 $ — $ — $ 241,368,688 $ 241,368,688 December 31, 2020 Carrying Unrecognized Unrecognized Estimated Cash and Cash Cash $ 23,494,920 $ — $ — $ 23,494,920 $ 23,494,920 Money market funds 29,363,391 — — 29,363,391 29,363,391 Reverse repurchase agreements 25,000,000 — — 25,000,000 25,000,000 Total Cash and cash equivalents $ 77,858,311 $ — $ — $ 77,858,311 $ 77,858,311 There were no marketable securities held at September 30, 2021 or December 31, 2020 .

Fair Value Measurements

Fair Value Measurements	9 Months Ended
	Sep. 30, 2021
Fair Value Disclosures [Abstract]
Fair Value Measurements	6. 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 , establishes a fair value hierarchy based on three levels of inputs, of which the first two are considered observable and the last unobservable, that may be used to measure fair value, which are the following: Level 1 – Quoted prices in active markets that are accessible at the market date for identical unrestricted assets or liabilities. Level 2 – Inputs other than Level 1 that are observable, either directly or indirectly, such as quoted prices for similar assets or liabilities; quoted prices in markets that are not active; or other inputs for which all significant inputs are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities. Level 3 – Unobservable inputs that are supported by little or no market activity and that are significant to the fair value of the assets or liabilities. There were no liabilities measured at fair value at September 30, 2021 or December 31, 2020. Money market funds included in cash and cash equivalents in the consolidated balance sheets, are recorded at fair value and considered as Level 1 inputs under the fair value hierarchy. Reverse repurchase agreements are recorded at fair market value and considered as Level 2 inputs under the fair value hierarchy. Financial instruments including cash equivalents, clinical trial prepayments to contract research organizations, and accounts payable are carried in the consolidated 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.

Prepaid Expenses and Other Curr

Prepaid Expenses and Other Current Assets	9 Months Ended
	Sep. 30, 2021
Prepaid Expense And Other Assets Current [Abstract]
Prepaid Expenses and Other Current Assets	7. PREPAID EXPENSES AND OTHER CURRENT ASSETS Prepaid expenses and other current assets were comprised of: September 30, December 31, 2021 2020 Deferred research and development expenses $ 4,532,903 $ 4,793,794 Miscellaneous prepaid expenses and other current assets 870,358 407,163 Total prepaid expenses and other current assets $ 5,403,261 $ 5,200,957

Accrued Expenses

Accrued Expenses	9 Months Ended
	Sep. 30, 2021
Payables And Accruals [Abstract]
Accrued Expenses	8. ACCRUED EXPENSES Accrued expenses were comprised of: September 30, December 31, 2021 2020 Accrued compensation $ 2,078,896 $ 1,323,138 Contingent consideration payable in stock — 2,500,000 Accrued research and development expenses 8,644,036 3,944,094 Accrued general and administrative expenses 529,143 367,533 Total accrued expenses $ 11,252,075 $ 8,134,765

Credit Facility

Credit Facility	9 Months Ended
	Sep. 30, 2021
Debt Disclosure [Abstract]
Credit Facility	9. CREDIT FACILITY The Company’s long-term debt obligation consists of amounts the Company is obligated to repay under its credit facility with Hercules Capital, Inc. (“Hercules”). In March 2019, the Company entered into a Loan and Security Agreement with Hercules and several banks and other financial institutions or entities, from time-to-time parties thereto (collectively, referred to as “Lender”), providing for a term loan of up to $ 60.0 million, subject to the satisfaction of certain conditions contained therein, that is secured by a lien covering all of the Company’s assets, other than the Company’s intellectual property (the “Loan and Security Agreement” or the “Hercules Credit Facility”). The Loan and Security Agreement provided for (i) an initial term loan advance of up to $ 5.0 million at the Company’s option, which expired unutilized on April 15, 2019; (ii) three additional term loan advances of up to $ 15.0 million each, at the Company’s option, available to the Company upon the occurrence of certain funding conditions prior to September 30, 2019 (the “2019 Tranche”), March 31, 2020 (the “2020 Tranche”), and March 31, 2021 (the “2021 Tranche”); and (iii) a final additional term loan advance (the “Fourth Loan Tranche”) of up to $ 10.0 million prior to December 31, 2021, at the Company’s option, subject to approval by the Lender’s investment committee. The 2019 Tranche was drawn down in full by the Company in September 2019 and the 2020 Tranche and 2021 Tranche expired unutilized prior to the Company satisfying the funding conditions for such tranche. On April 20, 2021, the Company entered into the First Amendment (the “First Amendment”) to the Loan and Security Agreement with Hercules. The First Amendment, among other things, (i) increased the Fourth Loan Tranche from $ 10.0 million to $ 20.0 million and extended the deadline for drawing down the Fourth Loan Tranche to June 1, 2022; (ii) lowered the variable per annum rate of interest on borrowings under the Loan and Security Agreement from the greater of (a) 9.10 % and (b) the prime rate (as reported in the Wall Street Journal or any successor publication thereto) plus 3.10 % to the greater of (x) the Prime Rate (as defined therein) plus 3.10% or (y) 8.60%; (iii) extended the expiration of the period in which interest-only payments on borrowings under the Loan and Security Agreement are required from May 1, 2021 to July 1, 2022; and (iv) following the satisfaction of certain conditions in April 2021, further extended the expiration of the interest-only period and the deadline for drawing down the Fourth Loan Tranche to May 1, 2023 . Repayment of the aggregate outstanding principal balance of the term loan, in monthly installments, commences upon expiration of the interest-only period and continues through October 1, 2023 (the “Maturity Date”). The First Amendment was determined to be a modification in accordance with FASB ASC Topic 470, Debt and did not result in extinguishment. Associated with this debt facility, the Company incurred a commitment charge of $ 25,000 , transaction costs of $ 273,186 , a fee of $ 375,000 upon closing, and is required to pay a fee (the “End of Term Charge”) of 6.95 % multiplied by the aggregate amount of advances under the Loan and Security Agreement at maturity. The fees, transaction costs, and the End of Term Charge are amortized to interest expense from 2019 through the Maturity Date using the effective interest method. The effective interest rate was 10.8 % at September 30, 2021 . At the Company’s option, the Company may elect to prepay all, but not less than all, of the outstanding term loan by paying the entire principal balance and all accrued and unpaid interest thereon plus all fees and other amounts due under the Loan and Security Agreement, including a prepayment charge equal to 1.5 % of the principal amount being prepaid. Following the effective time of the First Amendment and as of September 30, 2021 , an aggregate of $ 35 million, subject to the terms and conditions of the Loan and Security Agreement, may be made available to the Company for borrowing, $ 15 million of which was funded prior to the date of the First Amendment. Long-term debt consisted of the following: September 30, December 31, 2021 2020 Term loan payable $ 15,000,000 $ 15,000,000 End of term charge 651,139 445,464 Unamortized debt issuance costs ( 230,235 ) ( 351,232 ) Less: current portion — ( 3,659,776 ) Total long-term debt $ 15,420,904 $ 11,434,456 Future principal payments, including the End of Term Charge, are as follows: Years Ending December 31, 2021 $ — 2022 — 2023 16,042,500 Total $ 16,042,500 The Loan and Security Agreement also contains certain events of default, representations, warranties and non-financial covenants of the Company. As of September 30, 2021 , the Company was in material compliance with all covenants of the Hercules Credit Facility. In addition, subject to the terms of the Loan and Security Agreement, the Company granted the Lender the right to purchase up to an aggregate of $ 2.0 million of the Company’s equity securities, or instruments exercisable for or convertible into equity securities, sold to investors in financings upon the same terms and conditions afforded to such other investors.

Stockholders' Equity

Stockholders' Equity	9 Months Ended
	Sep. 30, 2021
Equity [Abstract]
Stockholders Equity	10. STOCKHOLDERS’ EQUITY In December 2018, the Company entered into an Open Market Sales Agreement SM (“2018 Jefferies Sales Agreement”) with Jefferies LLC (“Jefferies”), as sales agent, pursuant to which the Company could offer and sell, from time to time through Jefferies, shares of common stock providing for aggregate sales proceeds of up to $ 50.0 million. The Company had no obligation to sell any shares under the 2018 Jefferies Sales Agreement, and could at any time suspend solicitations and offers under the 2018 Jefferies Sales Agreement. From January 1, 2020 through December 31, 2020, the Company sold, at a volume-weighted average price of $ 4.62 per share, an aggregate of 9.4 million shares of common stock with net proceeds of $ 40.7 million after deducting commissions related to the 2018 Jefferies Sales Agreement and other offering costs. As of December 31, 2020, the Company had sold the maximum allowable amount and no further sales may be made under the 2018 Jefferies Sales Agreement. In January 2021, the Company sold 7.9 million shares of its common stock in an underwritten public offering at $ 9.50 per share, for an aggregate gross cash purchase price of $ 74.7 million or proceeds of $ 70.0 million after underwriters’ discount, commissions, and other offering expenses. In March 2021, the Company entered into an Open Market Sales Agreement SM (“2021 Jefferies Sales Agreement”) with Jefferies, as sales agent, pursuant to which the Company may offer and sell, from time to time through Jefferies, shares of common stock providing for aggregate sales proceeds of up to $ 100.0 million. The Company has no obligation to sell any shares under the 2021 Jefferies Sales Agreement, and could at any time suspend solicitations and offers under the 2021 Jefferies Sales Agreement. No sales had been made pursuant to the 2021 Jefferies Sales Agreement as of September 30, 2021. In May and June 2021, the Company sold an aggregate of 10.2 million shares of its common stock at a public offering price of $ 12.50 per share, in an underwritten public offering, for an aggregate gross cash purchase price of $ 127.8 million or proceeds of $ 119.8 million after underwriters’ discount and expenses, which included the partial exercise of the underwriters' option to purchase additional shares.

Income Taxes

Income Taxes	9 Months Ended
	Sep. 30, 2021
Income Tax Disclosure [Abstract]
Income Taxes	11. 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 Accounting Standards Codification (“ASC”) 740, Income Taxes (“ASC 740”) , the Company considers whether it is more likely than not that some portion or all the deferred tax assets will not be realized. Based on the weight of available evidence, primarily the incurrence of net losses since inception, anticipated net losses in the near future, reversals of existing temporary differences, and expiration of various federal and state attributes, the Company does not consider it more likely than not that some or all of the net deferred taxes will be realized. Accordingly, a 100 % valuation allowance has been applied against net deferred taxes. Under Section 382 of the Internal Revenue Code of 1986, as amended ("Section 382"), a corporation that undergoes an “ownership change” is subject to limitations on its ability to utilize its pre-change net operating losses (“NOLs”) and certain other tax assets (tax attributes) to offset future taxable income. In general, an ownership change occurs if the aggregate stock ownership of certain stockholders increases by more than 50 percentage points over such stockholders’ lowest percentage ownership during the testing period (generally three years). Transactions involving the Company’s common stock, within the testing period, even those outside the Company’s control, such as purchases or sales by investors, within the testing period could result in an ownership change. A limitation on the Company’s ability to utilize some or all its NOLs or credits could have a material adverse effect on the Company’s results of operations and cash flows. Prior to December 31, 2017, the Company believes it underwent three ownership changes, however, management believes there are sufficient “Built-In-Gains” to offset any Section 382 limitation generated by such ownership changes. Any future ownership changes, including those resulting from the Company’s future financing activities, may cause its existing tax attributes to incur additional limitations. All tax years are open for examination by the taxing authorities for both federal and state purposes. 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. Accordingly, in the provision for income taxes, the Company recognizes interest accrued related to unrecognized tax benefits and penalties; however, management is currently unaware of any uncertain tax positions. The Coronavirus Aid, Relief and Economic Security (“CARES”) Act was enacted in the United States on March 27, 2020. CARES includes several income tax provisions such as NOL carryback and carryforward benefits and other tax deduction benefits. As noted previously, the Company’s U.S. deferred tax asset has a full valuation, accordingly these NOL and other benefit provisions have no impact on the Company’s financial statements for the period ended September 30, 2021 .

Stock-Based Compensation

Stock-Based Compensation	9 Months Ended
	Sep. 30, 2021
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Stock-Based Compensation	12. STOCK-BASED COMPENSATION The Company has two equity incentive plans that provide 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 with a generally prescribed contractual term of ten years . As of September 30, 2021, there were 3,104,303 shares of common stock available for grant under the Company’s equity incentive plans. In 2019 and 2020 the Company granted performance cash awards. The performance cash awards vest in four annual installments from the date of grant and entitle the employees to receive a cash payment, on the earlier of (i) four years from the date of grant or (ii) a change of control, equal in value to the amount by which the then value of the Company’s common stock exceeds the base value. As of September 30, 2021 , $ 1.3 million was accrued as compensation expense for vested performance cash awards. The Company recognizes stock-based compensation expense over the requisite service period. The amounts included in the consolidated statements of operations relating to stock-based compensation associated with the two equity incentive plans and Helio founders’ shares are as follows: Three Months Ended September 30, Nine Months Ended September 30, 2021 2020 2021 2020 Research and development expenses $ 696,419 $ 1,236,902 $ 3,069,591 $ 3,429,592 General and administrative expenses 721,917 520,577 3,053,963 $ 2,023,928 Total stock-based compensation expense $ 1,418,337 $ 1,757,479 $ 6,123,554 $ 5,453,520 Stock Options The table below summarizes activity relating to stock options under the incentive plans for the nine months ended September 30, 2021: Number of Weighted Weighted Aggregate Outstanding at December 31, 2020 4,608,311 $ 5.73 Granted 905,169 $ 11.60 Exercised ( 634,214 ) $ 7.29 Forfeitures ( 316,396 ) $ 5.23 Outstanding at September 30, 2021 4,562,870 $ 6.71 6.92 $ 11,998,176 Exercisable at September 30, 2021 2,976,765 $ 5.81 5.93 $ 9,144,100 (a) The aggregate intrinsic value in this table was calculated on the positive difference, if any, between the closing price per share of the Company’s common stock on September 30, 2021 of $ 8.78 and the per share exercise price of the underlying options. As of September 30, 2021, unamortized stock-based compensation for all stock options outstanding was $ 8,315,227 and is expected to be recognized over a weighted average period of 2.56 years. Total unrecognized compensation cost will be adjusted for future forfeitures, if necessary. Restricted Stock Units The table below summarizes activity relating to RSUs for the nine months ended September 30, 2021: Number Outstanding at December 31, 2020 927,189 Granted 46,619 Cancelled ( 185,610 ) Vested ( 286,944 ) Outstanding at September 30, 2021 501,254 The weighted-average fair value of RSUs granted was $ 11.71 per share for the nine months ended September 30, 2021. As of September 30, 2021, the outstanding RSUs had unamortized stock-based compensation of $ 2.0 million with a weighted-average remaining recognition period of 2.07 years and an aggregate intrinsic value of $ 4.4 million . Employee Stock Purchase Plan At September 30, 2021, the Company had 1,233,557 shares available for issuance under the 2016 Employee Stock Purchase Plan (“2016 ESPP”). A summary of the weighted-average grant-date fair value, and total stock-based compensation expense recognized related to the 2016 ESPP are as follows: Nine Months Ended September 30, 2021 2020 Weighted-average grant-date fair value per share $ 4.27 $ 1.58 Total stock-based compensation expense $ 36,212 $ 37,604

Leases

Leases	9 Months Ended
	Sep. 30, 2021
Leases [Abstract]
Leases	13. LEASES The Company currently leases an office used to conduct business. The exercise of lease renewal options is at the Company’s discretion and the renewal to extend the lease terms are not included in the Company’s Right-Of-Use assets and lease liabilities as they are not reasonably certain of exercise. The Company regularly evaluates the renewal options and when they are reasonably certain of exercise, the Company includes the renewal period in its lease term. As the Company’s lease does not provide an implicit rate, the Company uses its incremental borrowing rate based on the information available at the lease commencement date in determining the present value of the lease payments. In August 2021, the Company entered into a lease amendment extending the lease by 18 months through June 30, 2023, which had an immaterial impact to the balance sheet as of September 30, 2021. As of September 30, 2021 , the Company maintained an unamortized Right-Of-Use asset with a corresponding operating lease liability of approximately $ 0.4 million based on the present value of the minimum rental payments in accordance with ASC Topic 842, Leases . The weighted average discount rate used for leases as of September 30, 2021 is 9.1 %. The weighted average lease term as of September 30, 2021 is 1.75 years. The operating lease expense for the nine months ended September 30, 2021 was $ 0.2 million. Maturities and balance sheet presentation of our lease liabilities for all operating leases as of September 30, 2021 is as follows: 2021 remaining total lease payments $ 441,835 Less: effect of discounting ( 35,078 ) Present value of lease liabilities $ 406,757 Current operating lease liabilities $ 222,158 Non-current operating lease liabilities 184,599 Total $ 406,757 The Company’s gross future minimum payments under all non-cancelable operating leases as of September 30, 2021, are: Total 2021 2022 2023 2024 Operating lease obligations $ 441,835 $ 60,782 $ 252,477 $ 128,576 $ —

Legal Proceedings

Legal Proceedings	9 Months Ended
	Sep. 30, 2021
Legal Proceedings [Abstract]
Legal Proceedings	14. LEGAL PROCEEDINGS In the ordinary course of its business, the Company may be involved in various legal proceedings involving contractual and employment relationships, patent or other intellectual property rights, and a variety of other matters. The Company is not aware of any pending legal proceedings that would reasonably be expected to have a material impact on the Company’s financial position or results of operations

Commitments and Contingencies

Commitments and Contingencies	9 Months Ended
	Sep. 30, 2021
Commitments And Contingencies Disclosure [Abstract]
Commitments and Contingencies	15. COMMITMENTS AND CONTINGENCIES There have been no material changes to the Company’s commitments and contingencies from the information provided in Note 14, Commitments and Contingencies , of the Notes to the Consolidated Financial Statements, included in the Company’s 2020 Form 10-K.

Basis of Presentation (Policies

Basis of Presentation (Policies)	9 Months Ended
	Sep. 30, 2021
Accounting Policies [Abstract]
Use of Estimates	Use of Estimates The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions, including fair value estimates for investments that affect the reported amounts of assets and liabilities and the disclosure of contingent assets and liabilities at the date of the consolidated financial statements, and the reported amounts of expenses during the reporting periods. The Company’s management evaluates its estimates and assumptions on an ongoing basis. Management’s most significant estimates in the Company’s consolidated financial statements include, but are not limited to, estimates related to clinical trial accruals, estimates related to prepaid and accrued research and development costs, acquired in-process research and development (“IPR&D”) expense, contingent liabilities, and accounting for income taxes and related valuation allowance. Although these estimates and assumptions are based on the Company’s knowledge of current events and actions it may undertake in the future, actual results may ultimately materially differ from these estimates and assumptions.
Summary of Significant Accounting Policies	Summary of Significant Accounting Policies There were no changes to significant accounting policies during the nine months ended September 30, 2021, as compared to the those identified in the 2020 Form 10-K.
Recent Accounting Pronouncements	Recent Accounting Pronouncements In June 2016, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) No. 2016-13, Financial Instruments—Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments (“ASU 2016-13”). ASU 2016-13 requires that credit losses be reported as an allowance using an expected losses model, representing the entity’s current estimate of credit losses expected to be incurred. The accounting guidance currently in effect is based on an incurred loss model. For available-for-sale debt securities with unrealized losses, this standard now requires allowances to be recorded instead of reducing the amortized cost of the investment. The amendments under ASU 2016-13 are effective for interim and annual fiscal periods beginning after December 15, 2022. The Company is continuing to evaluate the impact of ASU 2016-13 but does not expect the adoption of this ASU to have a material impact on its consolidated financial statements.

Net Loss Per Share (Tables)

Net Loss Per Share (Tables)	9 Months Ended
	Sep. 30, 2021
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: Three and Nine Months Ended September 30, 2021 2020 Options to purchase common stock 4,562,870 4,889,685 Restricted stock units 501,254 929,817 Nonvested founder shares (1) 46,674 188,638 Total of common stock equivalents 5,110,798 6,008,140 (1) Represents 46,674 and 188,638 shares of common stock that are issued and outstanding but that were subject to future vesting based on service requirements at September 30, 2021 and 2020 , respectively, and are, accordingly, not included in stockholders’ equity.

Cash, Cash Equivalents and Ma_2

Cash, Cash Equivalents and Marketable Securities (Tables)	9 Months Ended
	Sep. 30, 2021
Cash And Cash Equivalents [Abstract]
Schedule of Cash, and Cash Equivalents	Cash and cash equivalents, were comprised of: September 30, 2021 Carrying Unrecognized Unrecognized Estimated Cash and Cash Cash $ 111,966,754 $ — $ — $ 111,966,754 $ 111,966,754 Money market funds 4,401,934 — — 4,401,934 4,401,934 Reverse repurchase agreements 125,000,000 — — 125,000,000 125,000,000 Total Cash and cash equivalents $ 241,368,688 $ — $ — $ 241,368,688 $ 241,368,688 December 31, 2020 Carrying Unrecognized Unrecognized Estimated Cash and Cash Cash $ 23,494,920 $ — $ — $ 23,494,920 $ 23,494,920 Money market funds 29,363,391 — — 29,363,391 29,363,391 Reverse repurchase agreements 25,000,000 — — 25,000,000 25,000,000 Total Cash and cash equivalents $ 77,858,311 $ — $ — $ 77,858,311 $ 77,858,311

Prepaid Expenses and Other Cu_2

Prepaid Expenses and Other Current Assets (Tables)	9 Months Ended
	Sep. 30, 2021
Prepaid Expense And Other Assets Current [Abstract]
Schedule of Prepaid Expenses and Other Current Assets	Prepaid expenses and other current assets were comprised of: September 30, December 31, 2021 2020 Deferred research and development expenses $ 4,532,903 $ 4,793,794 Miscellaneous prepaid expenses and other current assets 870,358 407,163 Total prepaid expenses and other current assets $ 5,403,261 $ 5,200,957

Accrued Expenses (Tables)

Accrued Expenses (Tables)	9 Months Ended
	Sep. 30, 2021
Payables And Accruals [Abstract]
Schedule of Accrued Expenses	Accrued expenses were comprised of: September 30, December 31, 2021 2020 Accrued compensation $ 2,078,896 $ 1,323,138 Contingent consideration payable in stock — 2,500,000 Accrued research and development expenses 8,644,036 3,944,094 Accrued general and administrative expenses 529,143 367,533 Total accrued expenses $ 11,252,075 $ 8,134,765

Credit Facility (Tables)

Credit Facility (Tables)	9 Months Ended
	Sep. 30, 2021
Debt Disclosure [Abstract]
Schedule of Long-Term Debt	Long-term debt consisted of the following: September 30, December 31, 2021 2020 Term loan payable $ 15,000,000 $ 15,000,000 End of term charge 651,139 445,464 Unamortized debt issuance costs ( 230,235 ) ( 351,232 ) Less: current portion — ( 3,659,776 ) Total long-term debt $ 15,420,904 $ 11,434,456
Schedule of Principal Payments Including End of Term Charges	Future principal payments, including the End of Term Charge, are as follows: Years Ending December 31, 2021 $ — 2022 — 2023 16,042,500 Total $ 16,042,500

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	9 Months Ended
	Sep. 30, 2021
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Schedule of Stock-Based Compensation Expense	The amounts included in the consolidated statements of operations relating to stock-based compensation associated with the two equity incentive plans and Helio founders’ shares are as follows: Three Months Ended September 30, Nine Months Ended September 30, 2021 2020 2021 2020 Research and development expenses $ 696,419 $ 1,236,902 $ 3,069,591 $ 3,429,592 General and administrative expenses 721,917 520,577 3,053,963 $ 2,023,928 Total stock-based compensation expense $ 1,418,337 $ 1,757,479 $ 6,123,554 $ 5,453,520
Summary of Activity Relating to Stock Options	The table below summarizes activity relating to stock options under the incentive plans for the nine months ended September 30, 2021: Number of Weighted Weighted Aggregate Outstanding at December 31, 2020 4,608,311 $ 5.73 Granted 905,169 $ 11.60 Exercised ( 634,214 ) $ 7.29 Forfeitures ( 316,396 ) $ 5.23 Outstanding at September 30, 2021 4,562,870 $ 6.71 6.92 $ 11,998,176 Exercisable at September 30, 2021 2,976,765 $ 5.81 5.93 $ 9,144,100
Summary of Activity Relating to Restricted Stock Units	The table below summarizes activity relating to RSUs for the nine months ended September 30, 2021: Number Outstanding at December 31, 2020 927,189 Granted 46,619 Cancelled ( 185,610 ) Vested ( 286,944 ) Outstanding at September 30, 2021 501,254
Summary of Employee Stock Purchase Plan Activity	A summary of the weighted-average grant-date fair value, and total stock-based compensation expense recognized related to the 2016 ESPP are as follows: Nine Months Ended September 30, 2021 2020 Weighted-average grant-date fair value per share $ 4.27 $ 1.58 Total stock-based compensation expense $ 36,212 $ 37,604

Leases (Tables)

Leases (Tables)	9 Months Ended
	Sep. 30, 2021
Leases [Abstract]
Schedule of Maturities and Balance Sheet Presentation of Lease Liabilities	Maturities and balance sheet presentation of our lease liabilities for all operating leases as of September 30, 2021 is as follows: 2021 remaining total lease payments $ 441,835 Less: effect of discounting ( 35,078 ) Present value of lease liabilities $ 406,757 Current operating lease liabilities $ 222,158 Non-current operating lease liabilities 184,599 Total $ 406,757

Helio Vision Acquisition - Addi

Helio Vision Acquisition - Additional Information (Detail) - USD ($)	Jan. 28, 2019	Jan. 31, 2021	Sep. 30, 2021	Mar. 31, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Business Acquisition [Line Items]
Allocated Share Based Compensation Expense			$ 1,418,337		$ 1,757,479	$ 6,123,554	$ 5,453,520
Research and Development Expenses [Member]
Business Acquisition [Line Items]
Allocated Share Based Compensation Expense			$ 696,419		$ 1,236,902	3,069,591	3,429,592
Helio Vision Inc [Member]
Business Acquisition [Line Items]
Business combination, stock issued	1,160,444	246,562
Contingent consideration payable in stock								$ 2,500,000
Income tax benefit								500,000
Helio Vision Inc [Member] | Common Stock after FDA Approval prior to 10th Anniversary [Member]
Business Acquisition [Line Items]
Business combination, contingent consideration liability	$ 10,000,000
Helio Vision Inc [Member] | Common Stock after FDA Approval Prior to 12th Anniversary [Member]
Business Acquisition [Line Items]
Business combination, contingent consideration liability	$ 2,500,000
Helio Vision Inc [Member] | Common Stock after FDA Approval Prior to 12th Anniversary [Member] | Maximum [Member]
Business Acquisition [Line Items]
Business combination, contingent consideration stock to be issued	5,248,885
Helio Vision Inc [Member] | Tax Gross-up Payment in Event of Change of Control or Divesture [Member] | Maximum [Member]
Business Acquisition [Line Items]
Business combination, contingent consideration liability	$ 1,000,000
Helio Vision Inc [Member] | Founders [Member]
Business Acquisition [Line Items]
Business combination, stock issued	568,627
Helio Vision Inc [Member] | Founders [Member] | Service Based Awards [Member]
Business Acquisition [Line Items]
Share-based compensation award, vesting period	3 years
Vesting percentage of shares of common stock issued former security holders and advisor	92.00%
Helio Vision Inc [Member] | Founders [Member] | Restricted Stock [Member]
Business Acquisition [Line Items]
Share-based compensation award, vesting period	3 years
Helio Vision Inc [Member] | Founders [Member] | Research and Development Expenses [Member] | Restricted Stock [Member]
Business Acquisition [Line Items]
Allocated Share Based Compensation Expense						$ 900,000	$ 1,000,000
Helio Vision Inc [Member] | Non Founders [Member]
Business Acquisition [Line Items]
Business combination, stock issued	591,817
Helio Vision Inc [Member] | Milestone [Member]
Business Acquisition [Line Items]
Business combination, stock issued				246,562
Helio Vision Inc [Member] | Milestone [Member] | Research and Development Expenses [Member] | Restricted Stock [Member]
Business Acquisition [Line Items]
Allocated Share Based Compensation Expense								1,200,000
Expense related to the Milestone IPR&D								$ 1,800,000

Net Loss Per Share - Computatio

Net Loss Per Share - Computation of Diluted Weighted-Average Shares Outstanding (Detail) - shares		9 Months Ended
		Sep. 30, 2021	Sep. 30, 2020
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total of common stock equivalents		5,110,798	6,008,140
Options to Purchase Common Stock [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total of common stock equivalents		4,562,870	4,889,685
Restricted Stock Units [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total of common stock equivalents		501,254	929,817
Nonvested Founder Shares [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total of common stock equivalents	[1]	46,674	188,638
[1]	Represents 46,674 and 188,638 shares of common stock that are issued and outstanding but that were subject to future vesting based on service requirements at September 30, 2021 and 2020 , respectively, and are, accordingly, not included in stockholders’ equity.

Net Loss Per Share - Computat_2

Net Loss Per Share - Computation of Diluted Weighted-Average Shares Outstanding (Parenthetical) (Detail) - shares	Sep. 30, 2021	Sep. 30, 2020
Restricted Stock [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Number of common stock shares issued and outstanding subject of vesting shares based on service requirements	46,674	188,638

Cash, Cash Equivalents and Ma_3

Cash, Cash Equivalents and Marketable Securities - Schedule of Cash, and Cash Equivalents (Detail) - USD ($)	Sep. 30, 2021	Dec. 31, 2020
Cash Cash Equivalents And Marketable Securities [Line Items]
Cash	$ 111,966,754	$ 23,494,920
Money market funds	4,401,934	29,363,391
Reverse repurchase agreements	125,000,000	25,000,000
Total Cash and cash equivalents	241,368,688	77,858,311
Cash [Member]
Cash Cash Equivalents And Marketable Securities [Line Items]
Estimated Fair Value	111,966,754	23,494,920
Cash and Cash Equivalents	111,966,754	23,494,920
Money Market Funds [Member]
Cash Cash Equivalents And Marketable Securities [Line Items]
Estimated Fair Value	4,401,934	29,363,391
Cash and Cash Equivalents	4,401,934	29,363,391
Reverse Repurchase Agreements [Member]
Cash Cash Equivalents And Marketable Securities [Line Items]
Estimated Fair Value	125,000,000	25,000,000
Cash and Cash Equivalents	125,000,000	25,000,000
Total Cash and cash equivalents [Member]
Cash Cash Equivalents And Marketable Securities [Line Items]
Estimated Fair Value	241,368,688	77,858,311
Cash and Cash Equivalents	$ 241,368,688	$ 77,858,311

Cash, Cash Equivalents and Ma_4

Cash, Cash Equivalents and Marketable Securities - Additional Information (Detail) - USD ($)	Sep. 30, 2021	Dec. 31, 2020
Cash And Cash Equivalents [Abstract]
Marketable Securities	$ 0	$ 0

Fair Value Measurements - Addit

Fair Value Measurements - Additional Information (Detail) - USD ($)	Sep. 30, 2021	Dec. 31, 2020
Fair Value Disclosures [Abstract]
Liabilities measured at fair value on a recurring basis	$ 0	$ 0

Prepaid Expenses and Other Cu_3

Prepaid Expenses and Other Current Assets - Schedule of Prepaid Expenses and Other Current Assets (Detail) - USD ($)	Sep. 30, 2021	Dec. 31, 2020
Prepaid Expense And Other Assets Current [Abstract]
Deferred research and development expenses	$ 4,532,903	$ 4,793,794
Miscellaneous prepaid expenses and other current assets	870,358	407,163
Total prepaid expenses and other current assets	$ 5,403,261	$ 5,200,957

Accrued Expenses - Schedule of

Accrued Expenses - Schedule of Accrued Expenses (Detail) - USD ($)	Sep. 30, 2021	Dec. 31, 2020
Payables And Accruals [Abstract]
Accrued compensation	$ 2,078,896	$ 1,323,138
Contingent consideration payable in stock	0	2,500,000
Accrued research and development expenses	8,644,036	3,944,094
Accrued general and administrative expenses	529,143	367,533
Total accrued expenses	$ 11,252,075	$ 8,134,765

Credit Facility - Additional In

Credit Facility - Additional Information (Detail) - USD ($)	Apr. 20, 2021	Sep. 30, 2021	Dec. 31, 2020
Line Of Credit Facility [Line Items]
Proceeds from Long-term lines of credit			$ 16,042,500
Hercules Credit Facility [Member]
Line Of Credit Facility [Line Items]
Credit facility amount	$ 35,000,000	$ 60,000,000
Debt instrument annual interest rate		9.10%
Interest payment period		May 1, 2021
Interest payment extension period		May 1, 2023
Commitment charge		$ 25,000
Transaction costs		273,186
Credit facility fee		$ 375,000
Credit facility commitment fee percentage		6.95%
Credit facility, interest rate		10.80%
Credit facility prepayment fee percentage		1.50%
Loan funded prior to the date of amendment	15,000,000
Hercules Credit Facility [Member] | Maximum [Member]
Line Of Credit Facility [Line Items]
Loan agreement right to purchase aggregate amount of equity securities		$ 2,000,000
Hercules Credit Facility [Member] | Prime Rate [Member]
Line Of Credit Facility [Line Items]
Debt instrument variable annual interest rate		3.10%
Hercules Credit Facility [Member] | Term Loan Advance One [Member]
Line Of Credit Facility [Line Items]
Credit facility amount		$ 5,000,000
Hercules Credit Facility [Member] | Term Loan Advance Two [Member]
Line Of Credit Facility [Line Items]
Proceeds from Long-term lines of credit		15,000,000
Hercules Credit Facility [Member] | Term Loan Advance Three [Member]
Line Of Credit Facility [Line Items]
Proceeds from Long-term lines of credit		15,000,000
Hercules Credit Facility [Member] | Term Loan Advance Four [Member]
Line Of Credit Facility [Line Items]
Proceeds from Long-term lines of credit		15,000,000
Hercules Credit Facility [Member] | Term Loan Advance Five [Member]
Line Of Credit Facility [Line Items]
Proceeds from Long-term lines of credit	10,000,000	$ 10,000,000
Debt instrument, increase amount	$ 20,000,000

Credit Facility - Schedule of L

Credit Facility - Schedule of Long-Term Debt (Detail) - USD ($)	Sep. 30, 2021	Dec. 31, 2020
Line Of Credit Facility [Abstract]
Term loan payable	$ 15,000,000	$ 15,000,000
End of term charge	651,139	445,464
Unamortized debt issuance costs	(230,235)	(351,232)
Less: current portion	0	(3,659,776)
Total long-term debt	$ 15,420,904	$ 11,434,456

Credit Facility - Schedule of P

Credit Facility - Schedule of Principal Payments Incuding End of Term Charges (Detail)	Dec. 31, 2020USD ($)
Line Of Credit Facility [Abstract]
2021	$ 0
2022	0
2023	16,042,500
Total	$ 16,042,500

Stockholders' Equity - Addition

Stockholders' Equity - Additional Information (Detail) - USD ($)	1 Months Ended				2 Months Ended	3 Months Ended	9 Months Ended
	Jun. 30, 2021	Mar. 31, 2021	Jan. 31, 2021	Dec. 31, 2018	Jun. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	May 31, 2021
Class Of Stock [Line Items]
Proceeds from issuance of common stock, net of commissions and other offering costs							$ 189,811,611	$ 40,716,543
Issuance of common stock, net of issuance costs						$ 22,446,055	189,811,611	40,716,543
Proceeds from issuance of common stock, net of issuance costs							$ 189,811,611	$ 40,716,543
Common Voting Stock [Member]
Class Of Stock [Line Items]
Issuance of common stock, net of issuance costs, Shares						5,377,681	18,091,947	9,351,749
Issuance of common stock, net of issuance costs						$ 5,378	$ 18,092	$ 9,352
Issuance of common stock, net of issuance costs, Shares						5,377,681	18,091,947	9,351,749
Jefferies Sales Agreement [Member] | Maximum [Member]
Class Of Stock [Line Items]
Proceeds from issuance of common stock, net of commissions and other offering costs		$ 100,000,000
Proceeds from issuance of common stock, net of issuance costs		$ 100,000,000
Underwritten Public Offering [Member]
Class Of Stock [Line Items]
Proceeds from issuance of common stock, net of commissions and other offering costs			$ 70,000,000		$ 119,800,000
Proceeds from issuance of common stock, net of issuance costs			$ 70,000,000		$ 119,800,000
Underwritten Public Offering [Member] | Common Voting Stock [Member]
Class Of Stock [Line Items]
Issuance of common stock, net of issuance costs, Shares			7,900,000		10,200,000
Shares issued, price per share	$ 12.50		$ 9.50		$ 12.50				$ 12.50
Issuance of common stock, net of issuance costs	$ 127,800,000		$ 74,700,000
Issuance of common stock, net of issuance costs, Shares			7,900,000		10,200,000
Jefferies LLC [Member] | Jefferies Sales Agreement [Member]
Class Of Stock [Line Items]
Volume-weighted average price							$ 4.62
Issuance of common stock, net of issuance costs, Shares							9,400,000
Proceeds from issuance of common stock, net of commissions and other offering costs							$ 40,700,000
Issuance of common stock, net of issuance costs, Shares							9,400,000
Proceeds from issuance of common stock, net of issuance costs							$ 40,700,000
Jefferies LLC [Member] | Jefferies Sales Agreement [Member] | Maximum [Member]
Class Of Stock [Line Items]
Expected aggregate gross proceeds from issuance of stock				$ 50,000,000

Income Taxes - Additional Infor

Income Taxes - Additional Information (Detail)	9 Months Ended
	Sep. 30, 2021USD ($)
Income Tax [Line Items]
Deferred tax assets valuation allowance	100.00%
State and Federal [Member]
Income Tax [Line Items]
Income tax benefit	$ 0

Stock-Based Compensation - Addi

Stock-Based Compensation - Additional Information (Detail)	9 Months Ended		12 Months Ended
	Sep. 30, 2021USD ($)NumberOfPlan$ / sharesshares	Sep. 30, 2020$ / shares	Dec. 31, 2020	Dec. 31, 2019
Performance Cash Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted period			4 years	4 years
Share based compensation expense	$ 1,300,000
Options to Purchase Common Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unamortized stock-based compensation	$ 8,315,227
Weighted average recognition period	2 years 6 months 21 days
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unamortized stock-based compensation	$ 2,000,000
Granted | shares	46,619
Weighted-average grant-date fair value per share | $ / shares	$ 11.71
Weighted average remaining recognition period	2 years 25 days
Aggregate intrinsic value of options outstanding	$ 4,400,000
Equity Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of equity incentive plans | NumberOfPlan	2
Equity incentive plans, contractual term	ten years
Common stock available for issuance | shares	3,104,303
2016 Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock available for issuance | shares	1,233,557
Weighted-average grant-date fair value per share | $ / shares	$ 4.27	$ 1.58

Stock-Based Compensation - Sche

Stock-Based Compensation - Schedule of Stock-Based Compensation Expense (Detail) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Allocated Share Based Compensation Expense	$ 1,418,337	$ 1,757,479	$ 6,123,554	$ 5,453,520
Research and Development Expenses [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Allocated Share Based Compensation Expense	696,419	1,236,902	3,069,591	3,429,592
General and Administrative Expenses [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Allocated Share Based Compensation Expense	$ 721,917	$ 520,577	$ 3,053,963	$ 2,023,928

Stock-Based Compensation - Summ

Stock-Based Compensation - Summary of Stock Option Activity (Detail) - USD ($)	9 Months Ended
	Sep. 30, 2021
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Number of Shares Outstanding, Beginning Balance	4,608,311
Number of Shares, Granted	905,169
Number of Shares, Exercised	(634,214)
Number of Shares, Forfeitures	(316,396)
Number of Shares Outstanding, Ending Balance	4,562,870
Number of Shares Exercisable, Ending Balance	2,976,765
Weighted Average Exercise Price, Beginning Balance	$ 5.73
Weighted Average Exercise Price, Granted	11.60
Weighted Average Exercise Price, Exercised	7.29
Weighted Average Exercise Price, Forfeitures	5.23
Weighted Average Exercise Price, Ending Balance	6.71
Weighted Average Exercise Price Exercisable, Ending Balance	$ 5.81
Weighted Average Contractual Term, Outstanding	6 years 11 months 1 day
Weighted Average Contractual Term, Exercisable	5 years 11 months 4 days
Aggregate Intrinsic Value, Outstanding	$ 11,998,176
Aggregate Intrinsic Value, Exercisable	$ 9,144,100

Stock-Based Compensation - Su_2

Stock-Based Compensation - Summary of Stock Option Activity (Parenthetical) (Detail)	Sep. 30, 2021$ / shares
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Closing market value of common stock	$ 8.78

Stock-Based Compensation - Su_3

Stock-Based Compensation - Summary of Activity Relating to Restricted Stock Units (Detail) - Restricted Stock Units (RSUs) [Member]	9 Months Ended
	Sep. 30, 2021shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Shares Outstanding, Beginning Balance	927,189
Granted	46,619
Cancelled	(185,610)
Vested	(286,944)
Number of Shares Outstanding, Ending Balance	501,254

Stock-Based Compensation - Su_4

Stock-Based Compensation - Summary of Employee Stock Purchase Plan Activity (Detail) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Allocated Share Based Compensation Expense	$ 1,418,337	$ 1,757,479	$ 6,123,554	$ 5,453,520
2016 Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average grant-date fair value per share			$ 4.27	$ 1.58
Allocated Share Based Compensation Expense			$ 36,212	$ 37,604

Leases - Additional Information

Leases - Additional Information (Detail)	9 Months Ended
	Sep. 30, 2021USD ($)
Leases [Abstract]
Operating lease liability	$ 406,757
Operating leases, weighted average remaining lease term (years)	1 year 9 months
Operating leases, weighted average discount rate	9.10%
Operating lease, expense	$ 200,000

Leases - Schedule of Maturities

Leases - Schedule of Maturities and Balance Sheet Presentation of Lease Liabilities (Detail) - USD ($)	Sep. 30, 2021	Dec. 31, 2020
Leases [Abstract]
2021 remaining total lease payments	$ 441,835
Less: effect of discounting	(35,078)
Present value of lease liabilities	406,757
Current operating lease liabilities	222,158	$ 233,310
Non-current operating lease liabilities	184,599	$ 0
Present value of lease liabilities	$ 406,757

Leases - Schedule of Future Min

Leases - Schedule of Future Minimum Payments Under Non-Cancelable Operating Leases (Detail)	Sep. 30, 2021USD ($)
Leases [Abstract]
2021 remaining total lease payments	$ 441,835
Operating lease obligations, 2021	60,782
Operating lease obligations, 2022	252,477
Operating lease obligations, 2023	128,576
2024	$ 0