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Summary of Significant Accounting Policies - Additional Information (Detail) |  |  | 3 Months Ended | 9 Months Ended |  |  |
--- | --- | --- | --- | --- | --- | --- | ---
Dec. 18, 2020 shares | Sep. 14, 2020 | Sep. 30, 2021 USD ($) $ / shares shares | Sep. 30, 2020 USD ($) | Sep. 30, 2021 USD ($) Segment $ / shares shares | Sep. 30, 2020 USD ($) shares | Dec. 31, 2020 USD ($) shares | Mar. 31, 2020 shares | Dec. 31, 2019 USD ($)
Summary Of Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |  |
Net loss | $ |  |  | $ (9,817,000) | $ (6,144,000) | $ (25,700,000) | $ (16,907,000) |  |  |
Cash and cash equivalents | $ |  |  | 94,041,000 | $ 114,464,000 | 94,041,000 | $ 114,464,000 | $ 114,195,000 |  | $ 8,791,000
Working capital | $ |  |  | 91,500,000 |  | 91,500,000 |  |  |  |
Accumulated deficit | $ |  |  | (106,093,000) |  | $ (106,093,000) |  | (80,393,000) |  |
Cash, cash equivalents and restricted cash, maturity period |  |  |  |  | three months or less |  |  |  |
Cash equivalents | $ |  |  | $ 9,200,000 |  | $ 9,200,000 |  | $ 9,200,000 |  |
Number of operating business segments | Segment |  |  |  |  | 1 |  |  |  |
Warrants exercise price | $ / shares |  |  | $ 0.001 |  | $ 0.001 |  |  |  |
Antidilutive securities excluded from computation of earnings per share, amount |  |  |  |  | 674,295 | 1,828,531 |  |  |
2014 Stock Incentive Plan [Member] |  |  |  |  |  |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |  |
Increase in number of shares of common stock authorized for issuance |  |  |  |  |  |  |  | 28,816 |
Common stock, number of shares reserved for issuance |  |  |  |  |  |  | 0 |  |
2014 Employee Stock Purchase Plan [Member] |  |  |  |  |  |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |  |
Increase in number of shares of common stock authorized for issuance |  |  |  |  |  |  |  | 7,204 |
Common stock, number of shares reserved for issuance |  |  | 24,077 |  | 24,077 |  |  |  |
2020 Plan [Member] |  |  |  |  |  |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |  |
Common stock, number of shares reserved for issuance | 4,860,000 |  | 4,082,708 |  | 4,082,708 |  |  |  |
Percentage of issued and outstanding shares of common stock | 15.00% |  |  |  |  |  |  |  |
Equity compensation period | 3 years |  |  |  |  |  |  |  |
Stock Options [Member] | Board of Directors [Member] |  |  |  |  |  |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |  |
Expected life assumption using simplified method, description |  |  |  |  | For stock options granted to the board of directors, the Company determined the expected life assumption using the simplified method as the starting point with an average period of twelve (12) months added to take into account for the extended range of time of 12 to 18 months vested stock options granted to board of directors may be exercised upon termination. |  |  |  |
Expected life assumption using simplified method |  |  |  |  | 12 months |  |  |  |
Stock Options [Member] | Minimum [Member] | Board of Directors [Member] |  |  |  |  |  |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |  |
Vesting period of stock options granted |  |  |  |  | 12 months |  |  |  |
Stock Options [Member] | Maximum [Member] | Board of Directors [Member] |  |  |  |  |  |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |  |
Vesting period of stock options granted |  |  |  |  | 18 months |  |  |  |
Warrants [Member] |  |  |  |  |  |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |  |
Basic weighted average shares outstanding |  |  | 509,117 |  | 509,117 |  |  |  |
Anelixis [Member] | Minimum [Member] |  |  |  |  |  |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |  |
Expected life assumption using simplified method |  | 5 years |  |  |  |  |  |  |
Anelixis [Member] | Maximum [Member] |  |  |  |  |  |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |  |
Expected life assumption using simplified method |  | 5 years 10 months 24 days |  |  |  |  |  |  |
Otic Pharma [Member] | Anelixis [Member] |  |  |  |  |  |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |  |
Ownership percentage |  |  | 100.00% |  | 100.00% |  |  |  |
Otic Pharma, Inc. [Member] |  |  |  |  |  |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |  |
Ownership percentage |  |  | 100.00% |  | 100.00% |  |  |  |

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