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Summary of Significant Accounting Policies - Additional Information (Detail) |  | 3 Months Ended | 9 Months Ended |  |  |
--- | --- | --- | --- | --- | --- | ---
Dec. 18, 2020 shares | Sep. 30, 2022 USD ($) $ / shares shares | Sep. 30, 2021 USD ($) shares | Sep. 30, 2022 USD ($) Segment $ / shares shares | Sep. 30, 2021 USD ($) shares | Dec. 31, 2021 USD ($) | Dec. 31, 2020 USD ($) | Mar. 31, 2020 shares
Summary Of Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |
Net loss | $ |  | $ (10,471,000) | $ (9,817,000) | $ (29,582,000) | $ (25,700,000) |  |  |
Cash and cash equivalents | $ |  | 65,889,000 | $ 94,041,000 | 65,889,000 | $ 94,041,000 | $ 84,833,000 | $ 114,195,000 |
Working capital | $ |  | 61,300,000 |  | 61,300,000 |  |  |  |
Accumulated deficit | $ |  | (144,481,000) |  | $ (144,481,000) |  | (114,899,000) |  |
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 |  |  |  |
Basic weighted average shares outstanding |  | 14,265,905 | 14,815,852 | 14,289,729 | 14,820,822 |  |  |
Warrants exercise price | $ / shares |  | $ 0.001 |  | $ 0.001 |  |  |  |
Antidilutive securities excluded from computation of earnings per share, amount |  |  |  | 8,223,206 | 674,295 |  |  |
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 initially reserved for issuance |  | 0 |  | 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 initially reserved for issuance |  | 24,077 |  | 24,077 |  |  |  |
2020 Plan [Member] |  |  |  |  |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |
Common stock, number of shares initially reserved for issuance | 4,860,000 | 3,167,608 |  | 3,167,608 |  |  |  |
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 members of the Company’s board of directors (the “Board”), 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 members 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 |  |  |  |
Anelixis Therapeutics, LLC and Otic Pharma, Ltd. |  |  |  |  |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |
Ownership interest percentage |  |  |  | 100.00% |  |  |  |
Otic Pharma, Inc. [Member] |  |  |  |  |  |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |  |  |  |  |  |
Ownership interest percentage |  |  |  | 100.00% |  |  |  |

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