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Stockholders' Equity - Additional Information (Details) |  |  | 1 Months Ended | 3 Months Ended | 4 Months Ended | 6 Months Ended | 12 Months Ended |  |
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Dec. 16, 2020 USD ($) $ / shares shares | Oct. 29, 2019 USD ($) $ / shares shares | Jan. 31, 2022 shares | Aug. 31, 2021 shares | Nov. 30, 2020 USD ($) | Nov. 30, 2019 $ / shares shares | Oct. 31, 2019 shares | May 31, 2019 shares | Mar. 31, 2019 shares | Jun. 30, 2022 USD ($) shares | Mar. 31, 2022 shares | Jun. 30, 2021 USD ($) | Mar. 31, 2021 shares | May 06, 2019 USD ($) shares | Jun. 30, 2022 USD ($) $ / shares shares | Jun. 30, 2021 USD ($) $ / shares | Dec. 31, 2019 shares | Jan. 01, 2022 shares | Dec. 31, 2021 shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Preferred stock, shares authorized |  |  |  |  |  |  |  |  |  | 40,000,000 |  |  |  |  | 40,000,000 |  |  |  | 40,000,000
Preferred stock, shares issued |  |  |  |  |  |  |  |  |  | 0 |  |  |  |  | 0 |  |  |  | 0
Preferred stock, shares outstanding |  |  |  |  |  |  |  |  |  | 0 |  |  |  |  | 0 |  |  |  | 0
Stock options, granted |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1,520,297 |  |  |  |
Stock-based compensation cost | $ |  |  |  |  |  |  |  |  |  | $ 5,885,000 |  | $ 4,237,000 |  |  | $ 11,660,000 | $ 8,055,000 |  |  |
Common stock reserved for issuance |  |  |  |  |  |  |  |  |  | 8,829,888 |  |  |  |  | 8,829,888 |  |  |  |
Unrecognized stock-based compensation expense | $ |  |  |  |  |  |  |  |  |  | $ 47,900,000 |  |  |  |  | $ 47,900,000 |  |  |  |
Unrecognized stock-based compensation expense, weighted-average period for recognition |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 2 years 3 months 18 days |  |  |  |
Defined contribution plan employer contribution liabilities expense | $ |  |  |  |  |  |  |  |  |  | $ 300,000 |  | 200,000 |  |  | $ 900,000 | $ 600,000 |  |  |
Defined contribution plan, employer matching contribution, percentage |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 75.00% |  |  |  |
Employer discretionary match number of shares settled |  |  | 16,756 | 18,394 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Dividend yield |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 0.00% | 0.00% |  |  |
Stock Options |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Dividend yield |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 0.00% |  |  |  |
Stock options, PSUs and RSUs |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common stock reserved for issuance |  |  |  |  |  |  |  |  |  | 6,624,915 |  |  |  |  | 6,624,915 |  |  |  |
Restricted Stock Units (RSUs) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Unrecognized stock-based compensation expense | $ |  |  |  |  |  |  |  |  |  | $ 6,000,000.0 |  |  |  |  | $ 6,000,000.0 |  |  |  |
Unrecognized stock-based compensation expense, weighted-average period for recognition |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 2 years 1 month 6 days |  |  |  |
2019 Equity Incentive Plan |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common stock, shares authorized for issuance |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 2,231,739 |  |
Stock options, granted |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1,400,528 |  |
Number of shares available for issuance |  |  |  |  |  |  | 0 |  |  |  |  |  |  |  |  |  |  |  |
2019 Equity Incentive Plan | Restricted Stock |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stock awards, granted |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 16,260 |  |
2019 Incentive Award Plan |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Annual increase to shares available for issuance percentage of outstanding common stock |  |  |  |  |  |  | 5.00% |  |  |  |  |  |  |  |  |  |  |  |
Equity plan, description |  |  |  |  |  |  |  |  |  |  |  |  |  |  | The number of shares initially available for issuance will be increased by (i) the number of shares subject to stock options or similar awards granted under the Existing Incentive Plan that expire or otherwise terminate without having been exercised in full after the effective date of the 2019 Plan and unvested shares issued pursuant to awards granted under the Existing Incentive Plan that are forfeited to or repurchased by the Company after the effective date of the 2019 Plan, with the maximum number of shares to be added to the 2019 Plan pursuant to clause (i) above equal to 1,416,788 shares, and (ii) an annual increase on January 1 of each calendar year beginning in 2020 and ending in 2029, equal to the lesser of (a) 5% of the shares of common stock outstanding on the final day of the immediately preceding calendar year and (b) such smaller number of shares as determined by the board of directors. As of June 30, 2022, 1,311,660 shares remain available for issuance, which reflects 2,148,734 of stock option, performance-based unit, or PSU, and restricted stock unit, or RSU, awards granted, and 104,848 of awards cancelled or forfeited, during the six months ended June 30, 2022 as well as an annual increase of 1,582,802 shares authorized on January 1, 2022. |  |  |  |
Number of shares remain available for issuance, annual increase |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1,582,802 |
Common stock reserved for issuance |  |  |  |  |  |  |  |  |  | 1,311,660 |  |  |  |  | 1,311,660 |  |  |  |
2019 Incentive Award Plan | Performance-Based Stock Units (PSU) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stock awards, granted |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 37,500 |  |  |  |
Stock-based compensation cost | $ |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 0 |  |  |  |
Unrecognized stock-based compensation expense | $ |  |  |  |  |  |  |  |  |  | $ 13,000,000.0 |  |  |  |  | $ 13,000,000.0 |  |  |  |
2019 Incentive Award Plan | Stock options, PSUs and RSUs |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of awards, granted |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 2,148,734 |  |  |  |
Number of awards, cancelled or forfeited |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 104,848 |  |  |  |
2019 Incentive Award Plan | Restricted Stock Units (RSUs) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stock awards, granted |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 590,937 |  |  |  |
Employee Stock Purchase Plan |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of shares available for issuance |  |  |  |  |  |  |  |  |  | 802,085 |  |  |  |  | 802,085 |  |  |  |
Annual increase to shares available for issuance percentage of outstanding common stock |  |  |  |  |  |  | 1.00% |  |  |  |  |  |  |  |  |  |  |  |
Equity plan, description |  |  |  |  |  |  |  |  |  |  |  |  |  |  | In addition, the number of shares available for issuance under the ESPP will be annually increased on January 1 of each calendar year beginning in 2020 and ending in 2029, by an amount equal to the lesser of: (i) 1% of the shares outstanding on the final day of the immediately preceding calendar year and (ii) such smaller number of shares as is determined by the board of directors. As of June 30, 2022, 802,085 shares of common stock remain available for issuance, which includes the 39,951 shares sold to employees during the six months ended June 30, 2022 |  |  |  |
Stock-based compensation cost | $ |  |  |  |  |  |  |  |  |  | $ 200,000 |  | $ 100,000 |  |  | $ 300,000 | $ 200,000 |  |  |
Common stock reserved for issuance |  |  |  |  |  |  | 270,000 |  |  | 802,085 |  |  |  |  | 802,085 |  |  |  |
Number of shares issued |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 39,951 |  |  |  |
Estimated weighted-average fair value | $ / shares |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 5.31 | $ 15.85 |  |  |
Unrecognized stock-based compensation expense | $ |  |  |  |  |  |  |  |  |  | $ 28,000 |  |  |  |  | $ 28,000 |  |  |  |
Unrecognized stock-based compensation expense, weighted-average period for recognition |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 15 days |  |  |  |
Dividend yield |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 0.00% | 0.00% |  |  |
Underwritten Public Offering |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Shares issued | 2,250,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common stock, price per share | $ / shares | $ 42.00 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Proceeds from issuance initial public offering gross | $ | $ 94,500,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Purchase price per share after deducting underwriting discounts and commissions | $ / shares | $ 39.48 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net proceeds after deducting underwriters commission | $ | $ 88,800,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Purchase of additional offering expenses | $ | $ 200,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
At-the-Market Offering Program |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Shares issued |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 0 |  |  |  |
Employee and Nonemployee Director |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Estimated weighted-average fair value | $ / shares |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 8.96 |  |  |  |
Open Market Sale Agreement with Jefferies LLC | At-the-Market Offering Program |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Sales commission payable as a percentage of sale of gross sales price per share |  |  |  |  | 3.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |
Open Market Sale Agreement with Jefferies LLC | At-the-Market Offering Program | Maximum |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Aggregate offering price through equity financing | $ |  |  |  |  | $ 125,000,000.0 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common Stock |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Shares issued |  |  |  |  |  |  |  |  |  |  |  |  |  | 2,524,852 |  |  |  |  |
Number of shares authorized to repurchase |  |  |  |  |  |  |  |  | 3,373,408 |  |  |  |  |  |  |  |  |  |
Stock repurchase program, number of shares right lapse |  |  |  |  |  |  |  |  | 843,352 |  |  |  |  |  |  |  |  |  |
Remaining number of shares to be repurchased |  |  |  |  |  |  |  |  | 2,530,056 |  |  |  |  |  |  |  |  |  |
Stock repurchase program, period in force |  |  |  |  |  |  |  |  | 48 months |  |  |  |  |  |  |  |  |  |
Stock repurchase program expiration period |  |  |  |  |  |  |  |  | 2023-03 |  |  |  |  |  |  |  |  |  |
Proceeds from issuance of shares | $ |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 1,000 |  |  |  |  |
Repurchase right lapse each month after first anniversary, shares |  |  |  |  |  |  |  |  |  |  |  |  |  | 0.000208 |  |  |  |  |
Repurchases of shares |  |  |  |  |  | 17,560 |  |  |  |  |  |  |  |  |  |  |  |  |
Shares aggregate repurchase price | $ / shares |  |  |  |  |  | $ 5.20 |  |  |  |  |  |  |  |  |  |  |  |  |
Employer discretionary match number of shares settled |  |  |  |  |  |  |  |  |  |  | 16,756 |  | 8,356 |  |  |  |  |  |
Common Stock | 2019 Incentive Award Plan |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Additional number of shares available for issuance |  |  |  |  |  |  | 1,416,788 |  |  |  |  |  |  |  |  |  |  |  |
Common Stock | Employee Stock Purchase Plan |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Maximum percentage of eligible compensation contributed by participants |  |  |  |  |  |  | 20.00% |  |  |  |  |  |  |  |  |  |  |  |
Common Stock | IPO |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Shares issued |  | 10,997,630 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common stock, price per share | $ / shares |  | $ 19.00 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Proceeds from Initial Public Offering (IPO) | $ |  | $ 191,500,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common Stock | Underwritten Public Offering |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Shares issued |  | 1,434,473 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common Stock | Employees |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Remaining number of shares to be repurchased |  |  |  |  |  |  |  |  |  | 462,432 |  |  |  |  | 462,432 |  |  |  |
Common Stock | First Anniversary |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Initial repurchase right lapse rate |  |  |  |  |  |  |  |  |  |  |  |  |  | 25.00% |  |  |  |  |
Common Stock | Takeda License |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Shares issued |  |  |  |  |  |  |  | 1,084,000 |  |  |  |  |  |  |  |  |  |  |
Common Stock | Founders |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Remaining number of shares to be repurchased |  |  |  |  |  |  |  |  |  | 237,192 |  |  |  |  | 237,192 |  |  |  |
Common Stock | Frazier |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share Based Compensation Arrangement By Share Based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Shares issued |  |  |  |  |  |  |  |  | 1,491,072 |  |  |  |  |  |  |  |  |  |

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