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Stockholders' Equity - Additional Information (Detail) |  |  |  |  |  |  |  | 12 Months Ended |
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Sep. 21, 2021 shares | Dec. 23, 2020 USD ($) shares | Dec. 18, 2020 $ / shares shares | Sep. 14, 2020 USD ($) shares | Jun. 10, 2020 shares | Feb. 13, 2020 USD ($) Feature $ / shares shares | Jan. 15, 2020 USD ($) $ / shares shares | Dec. 31, 2021 USD ($) $ / shares shares | Dec. 31, 2020 USD ($) $ / shares shares | Feb. 19, 2020 shares
Class Of Stock [Line Items] |  |  |  |  |  |  |  |  |  |
Proceeds from issuance of non-voting preferred stock in connection with PIPE transaction, net | $ |  |  |  |  |  |  |  |  | $ 95,226,000 |
Proceeds from issuance of common stock | $ |  |  |  |  |  |  |  |  | 9,000,000 |
Warrant inducement expense | $ |  |  |  |  |  |  |  |  | $ 4,829,000 |
September 2020 Anelixis Acquisition [Member] | Stock Options [Member] |  |  |  |  |  |  |  |  |  |
Class Of Stock [Line Items] |  |  |  |  |  |  |  |  |  |
Estimated fair value, assumed and replaced value | $ |  |  |  | $ 3,000,000.0 |  |  |  |  |  |
Common Stock [Member] |  |  |  |  |  |  |  |  |  |
Class Of Stock [Line Items] |  |  |  |  |  |  |  |  |  |
Issuance of common stock in connection with conversion of Series X preferred stock, Shares |  |  |  |  |  |  |  |  | 210,888 |
Common stock number of shares issued |  | 1,004,111 |  |  |  |  |  |  | 1,004,111 |
Proceeds from issuance of common stock | $ |  | $ 9,000,000.0 |  |  |  |  |  |  |  |
Issuance of common stock in connection with exercise of warrants, net of issuance costs, Shares |  |  |  |  |  |  |  |  | 421,772 |
Warrants available for exercise |  |  |  |  |  |  |  | 1,145,631 |  |
Common Stock [Member] | September 2020 Anelixis Acquisition [Member] |  |  |  |  |  |  |  |  |  |
Class Of Stock [Line Items] |  |  |  |  |  |  |  |  |  |
Issuance of common stock |  |  |  | 175,488 |  |  |  |  |  |
Warrant [Member] | September 2020 Anelixis Acquisition [Member] |  |  |  |  |  |  |  |  |  |
Class Of Stock [Line Items] |  |  |  |  |  |  |  |  |  |
Estimated fair value, assumed and replaced value | $ |  |  |  | $ 12,900,000 |  |  |  |  |  |
Series X Non-voting Convertible Preferred Stock [Member] |  |  |  |  |  |  |  |  |  |
Class Of Stock [Line Items] |  |  |  |  |  |  |  |  |  |
Conversion of stock, shares converted |  |  |  |  | 3,285 |  |  |  |  |
Number of embedded features within preferred stock | Feature |  |  |  |  |  | 2 |  |  |  |
Issuance of common stock in connection with conversion of Series X preferred stock, Shares |  |  |  |  |  |  |  |  | (3,796) |
Series X Non-voting Convertible Preferred Stock [Member] | Common Stock [Member] |  |  |  |  |  |  |  |  |  |
Class Of Stock [Line Items] |  |  |  |  |  |  |  |  |  |
Issuance of common stock in connection with conversion of Series X preferred stock, Shares |  |  |  |  | 182,500 |  |  |  |  |
Series X1 Preferred Stock [Member] |  |  |  |  |  |  |  |  |  |
Class Of Stock [Line Items] |  |  |  |  |  |  |  |  |  |
Preferred stock, par value | $ / shares |  |  | $ 0.001 |  |  |  |  |  |  |
Shares of common stock issued upon conversion of each share of preferred stock |  |  |  |  |  |  |  | 2,789,301 |  |
Warrants available for exercise |  |  |  |  |  |  |  | 50,207.419 |  |
Series X1 Preferred Stock [Member] | September 2020 Anelixis Acquisition [Member] |  |  |  |  |  |  |  |  |  |
Class Of Stock [Line Items] |  |  |  |  |  |  |  |  |  |
Issuance of common stock |  |  |  | 140,026 |  |  |  |  |  |
Series X1 Preferred Stock [Member] | September 2020 Anelixis Acquisition [Member] | Stock Options [Member] |  |  |  |  |  |  |  |  |  |
Class Of Stock [Line Items] |  |  |  |  |  |  |  |  |  |
Estimated fair value, assumed and replaced |  |  |  | 1,346,398 |  |  |  |  |  |
Estimated fair value, assumed and replaced value | $ |  |  |  | $ 6,000,000.0 |  |  |  |  |  |
Series X1 Preferred Stock [Member] | Warrant [Member] | September 2020 Anelixis Acquisition [Member] |  |  |  |  |  |  |  |  |  |
Class Of Stock [Line Items] |  |  |  |  |  |  |  |  |  |
Estimated fair value, assumed and replaced |  |  |  | 55,583.875 |  |  |  |  |  |
Series X1 Non-voting Convertible Preferred Stock [Member] |  |  |  |  |  |  |  |  |  |
Class Of Stock [Line Items] |  |  |  |  |  |  |  |  |  |
Preferred stock, par value | $ / shares |  |  | $ 0.001 |  |  |  |  | $ 0.001 | $ 0.001 |
Issuance of common stock in connection with conversion of Series X preferred stock, Shares |  |  | 231,068 |  |  |  |  |  | (231,068) |
Issuance of preferred stock |  |  |  |  |  |  |  |  | 199,112 |
Series X1 Non-voting Convertible Preferred Stock [Member] | Common Stock [Member] |  |  |  |  |  |  |  |  |  |
Class Of Stock [Line Items] |  |  |  |  |  |  |  |  |  |
Issuance of common stock in connection with conversion of Series X preferred stock, Shares |  |  |  |  |  |  |  |  | 12,837,056 |
2020 Common Stock Exchange Agreement [Member] | Exchanging Stockholders [Member] |  |  |  |  |  |  |  |  |  |
Class Of Stock [Line Items] |  |  |  |  |  |  |  |  |  |
Reimbursement of expenses | $ |  |  |  |  |  | $ 25,000 |  |  |  |
Conversion of stock blocker provision percentage |  |  |  |  |  | 9.99% |  |  |  |
2020 Common Stock Exchange Agreement [Member] | Exchanging Stockholders [Member] | Common Stock [Member] |  |  |  |  |  |  |  |  |  |
Class Of Stock [Line Items] |  |  |  |  |  |  |  |  |  |
Conversion of stock, shares converted |  |  |  |  |  | 210,888 |  |  |  |
Shares of common stock issued upon conversion of each share of preferred stock |  |  |  |  |  | 55.5556 |  |  |  | 55.5556
2020 Common Stock Exchange Agreement [Member] | Exchanging Stockholders [Member] | Series X Non-voting Convertible Preferred Stock [Member] |  |  |  |  |  |  |  |  |  |
Class Of Stock [Line Items] |  |  |  |  |  |  |  |  |  |
Conversion of stock, shares issued |  |  |  |  |  | 3,796 |  |  |  |
Number of designated preferred stock shares |  |  |  |  |  | 10,000 |  |  |  |
Preferred stock, par value | $ / shares |  |  |  |  |  | $ 0.001 |  |  |  |
Stock Purchase Agreement [Member] | Series X Non-voting Convertible Preferred Stock [Member] | Common Stock [Member] |  |  |  |  |  |  |  |  |  |
Class Of Stock [Line Items] |  |  |  |  |  |  |  |  |  |
Shares of common stock issued upon conversion of each share of preferred stock |  |  |  | 55.5556 |  |  |  |  |  |
Conversion of stock blocker provision percentage |  |  |  | 9.99% |  |  |  |  |  |
Stock Purchase Agreement [Member] | Series X1 Preferred Stock [Member] |  |  |  |  |  |  |  |  |  |
Class Of Stock [Line Items] |  |  |  |  |  |  |  |  |  |
Conversion of stock, shares converted |  |  | 231,068 |  |  |  |  |  |  |
Preferred stock, par value | $ / shares |  |  | $ 0.001 |  |  |  |  |  |  |
Issuance of preferred stock |  |  |  | 199,112 |  |  |  |  |  |
Preferred stock shares aggregate purchase price |  |  |  | 99,100,000 |  |  |  |  |  |
Proceeds from issuance of non-voting preferred stock in connection with PIPE transaction, net | $ |  |  |  | $ 95,200,000 |  |  |  |  |  |
Business combination additional commitments in equity financing | $ |  |  |  | $ 9,000,000.0 |  |  |  |  |  |
Common stock number of shares issued |  | 1,004,111 |  |  |  |  |  |  |  |
Proceeds from issuance of common stock | $ |  | $ 9,000,000.0 |  |  |  |  |  |  |  |
Stock Purchase Agreement [Member] | Series X1 Preferred Stock [Member] | Common Stock [Member] |  |  |  |  |  |  |  |  |  |
Class Of Stock [Line Items] |  |  |  |  |  |  |  |  |  |
Shares of common stock issued upon conversion of each share of preferred stock |  |  |  | 55.5556 |  |  |  |  |  |
Issuance of common stock in connection with conversion of Series X preferred stock, Shares |  |  | 12,837,056 |  |  |  |  |  |  |
2020 Warrant Exercise Transactions [Member] | Warrants [Member] |  |  |  |  |  |  |  |  |  |
Class Of Stock [Line Items] |  |  |  |  |  |  |  |  |  |
Warrants to purchase common stock |  |  |  |  |  |  | 383,235 |  |  |
Warrant reduced exercise price per share | $ / shares |  |  |  |  |  |  | $ 12.87 |  |  |
Warrant additional exercise price per share | $ / shares |  |  |  |  |  |  | $ 2.25 |  |  |
Common stock shares gross proceeds value | $ |  |  |  |  |  |  | $ 5,800,000 |  |  |
2020 Warrant Exercise Transactions [Member] | Common Stock [Member] |  |  |  |  |  |  |  |  |  |
Class Of Stock [Line Items] |  |  |  |  |  |  |  |  |  |
Warrants to purchase common stock |  |  |  |  |  |  |  |  | 64,171 |
Common stock shares gross proceeds value | $ |  |  |  |  |  |  |  |  | $ 188,773 |
Warrant exercise price per share | $ / shares |  |  |  |  |  |  | $ 12.96 |  |  |
Warrants exercisable term |  |  |  |  |  |  | 5 years 6 months |  |  |
Issuance of common stock in connection with exercise of warrants, net of issuance costs, Shares |  |  |  |  |  |  |  |  | 28,553 |
Number of shares exercised |  |  |  |  |  |  |  |  | 9,985 |
2020 Warrant Exercise Transactions [Member] | Common Stock [Member] | Placement Agent [Member] |  |  |  |  |  |  |  |  |  |
Class Of Stock [Line Items] |  |  |  |  |  |  |  |  |  |
Warrant exercise price per share | $ / shares |  |  |  |  |  |  | $ 18.90 |  |  |
Percentage of warrants to issue shares of common stock |  |  |  |  |  |  | 5.00% |  |  |
2020 Warrant Exercise Transactions [Member] | Common Stock [Member] | Maximum [Member] |  |  |  |  |  |  |  |  |  |
Class Of Stock [Line Items] |  |  |  |  |  |  |  |  |  |
Warrants to purchase common stock |  |  |  |  |  |  | 383,235 |  |  |
2020 Warrant Exercise Transactions [Member] | Common Stock [Member] | Maximum [Member] | Placement Agent [Member] |  |  |  |  |  |  |  |  |  |
Class Of Stock [Line Items] |  |  |  |  |  |  |  |  |  |
Warrants to purchase common stock |  |  |  |  |  |  | 19,162 |  |  |
Series X Exchange Agreement [Member] | BVF Exchanging Stockholders, Series X Exchanging Stockholders [Member] | Common Stock [Member] |  |  |  |  |  |  |  |  |  |
Class Of Stock [Line Items] |  |  |  |  |  |  |  |  |  |
Conversion of stock, shares converted |  |  |  |  |  |  |  |  | 344,666 |
Series X Exchange Agreement [Member] | BVF Exchanging Stockholders, Series X Exchanging Stockholders [Member] | Series X Non-voting Convertible Preferred Stock [Member] |  |  |  |  |  |  |  |  |  |
Class Of Stock [Line Items] |  |  |  |  |  |  |  |  |  |
Conversion of stock, shares issued |  |  |  |  |  |  |  |  | 6,203.98 |
Warrant Exchange Agreement and Exchange Agreements [Member] | BVF Exchanging Stockholders | Common Stock [Member] |  |  |  |  |  |  |  |  |  |
Class Of Stock [Line Items] |  |  |  |  |  |  |  |  |  |
Warrants to purchase common stock |  |  |  |  |  |  |  |  | 509,117 |
September 2021 Warrant Exchange Agreement [Member] | Common Stock [Member] |  |  |  |  |  |  |  |  |  |
Class Of Stock [Line Items] |  |  |  |  |  |  |  |  |  |
Warrants issued | 298,692 |  |  |  |  |  |  |  |  |
September 2021 Warrant Exchange Agreement [Member] | Series X1 Non-voting Convertible Preferred Stock [Member] | Common Stock [Member] |  |  |  |  |  |  |  |  |  |
Class Of Stock [Line Items] |  |  |  |  |  |  |  |  |  |
Warrants exercisable for exchange | 5,376.456 |  |  |  |  |  |  |  |  |
Equity Distribution Agreement [Member] | Jeffries LLC [Member] |  |  |  |  |  |  |  |  |  |
Class Of Stock [Line Items] |  |  |  |  |  |  |  |  |  |
Common stock number of shares issued |  |  |  |  |  |  |  | 0 |  |
Equity distribution agreement maximum value of common shares issuable | $ |  |  |  |  |  |  |  | $ 75,000,000.0 |  |

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