Entity Central Index Key Cash and cash equivalents fair value disclosure accumulated gross unrealized gain before tax. Cash and cash equivalents fair value disclosure accumulated gross unrealized loss before tax. Assets fair value disclosure accumulated gross unrealized gain before tax. Assets fair value disclosure accumulated gross unrealized loss before tax. Cover [Abstract] Document Type Document Type Amendment Flag Amendment Flag Document Period End Date Document Period End Date Document Fiscal Year Focus Document Fiscal Year Focus Document Fiscal Period Focus Document Fiscal Period Focus Trading Symbol Trading Symbol Entity Registrant Name Entity Registrant Name Entity Central Index Key Entity Current Reporting Status Entity Current Reporting Status Current Fiscal Year End Date Current Fiscal Year End Date Entity Filer Category Entity Filer Category Entity Shell Company Entity Shell Company Entity Small Business Entity Small Business Entity Emerging Growth Company Entity Emerging Growth Company Entity Ex Transition Period Entity Ex Transition Period Entity Common Stock, Shares Outstanding Entity Common Stock Shares Outstanding Entity File Number Entity File Number Entity Tax Identification Number Entity Tax Identification Number Entity Address, Address Line One Entity Address Address Line1 Entity Address, Address Line Two Entity Address Address Line2 Entity Address, City or Town Entity Address City Or Town Entity Address, State or Province Entity Address State Or Province Entity Address, Postal Zip Code Entity Address Postal Zip Code City Area Code City Area Code Local Phone Number Local Phone Number Entity Interactive Data Current Entity Interactive Data Current Title of 12(b) Security Security12b Title Security Exchange Name Security Exchange Name Entity Incorporation, State or Country Code Entity Incorporation State Country Code Document Annual Report Document Annual Report Document Transition Report Document Transition Report Entity Well-known Seasoned Issuer Entity Well Known Seasoned Issuer Entity Voluntary Filers Entity Voluntary Filers Entity Public Float Entity Public Float ICFR Auditor Attestation Flag Icfr Auditor Attestation Flag Preferred stock tranche obligation. Statement Of Financial Position [Abstract] Assets Assets [Abstract] Current assets: Assets Current [Abstract] Cash and cash equivalents Cash And Cash Equivalents At Carrying Value Short-term investments Short Term Investments Prepaid expenses and other current assets Prepaid Expense And Other Assets Current Total current assets Assets Current Property and equipment, net Property Plant And Equipment Net Prepaid expenses and other non-current assets Prepaid Expense And Other Assets Noncurrent Total assets Assets Liabilities, Convertible Preferred Stock and Stockholders’ Equity (Deficit) Liabilities And Stockholders Equity [Abstract] Current liabilities: Liabilities Current [Abstract] Accounts payable Accounts Payable Current Accrued research and development Accrued Liabilities Current Other current liabilities Other Liabilities Current Preferred stock tranche obligation Preferred Stock Tranche Obligation Total current liabilities Liabilities Current Deferred rent, long term portion Deferred Rent Credit Noncurrent Total liabilities Liabilities Commitments and contingencies (Note 5) Commitments And Contingencies Convertible preferred stock, $0.0001 par value; 142,150,096 shares authorized as of December 31, 2019, 0 and 117,809,883 shares issued and outstanding as of December 31, 2020 and 2019, respectively; aggregate liquidation value of $0 and $148,592 as of December 31, 2020 and 2019, respectively Temporary Equity Carrying Amount Attributable To Parent Stockholders’ Equity (Deficit): Stockholders Equity [Abstract] Preferred stock, $0.0001 par value; 10,000,000 authorized, no shares outstanding as of December 31, 2020 and 2019, respectively Preferred Stock Value Common stock, $0.0001 par value; 500,000,000 and 188,000,000 shares authorized, 20,979,265 and 1,371,467 shares issued and outstanding as of December 31, 2020 and 2019, respectively Common Stock Value Additional paid-in capital Additional Paid In Capital Common Stock Accumulated deficit Retained Earnings Accumulated Deficit Accumulated other comprehensive (loss) income Accumulated Other Comprehensive Income Loss Net Of Tax Total stockholders’ equity (deficit) Stockholders Equity Total liabilities, convertible preferred stock and stockholders’ equity (deficit) Liabilities And Stockholders Equity Statement [Table] Statement [Table] Class of Stock Statement Class Of Stock [Axis] Class of Stock Class Of Stock [Domain] Convertible Preferred Stock Convertible Preferred Stock [Member] Statement [Line Items] Statement [Line Items] Preferred stock, par value Preferred Stock Par Or Stated Value Per Share Preferred stock, shares authorized Preferred Stock Shares Authorized Preferred stock, shares issued Preferred Stock Shares Issued Preferred stock, shares outstanding Preferred Stock Shares Outstanding Preferred stock, aggregate liquidation value Preferred Stock Liquidation Preference Value Common stock, par value Common Stock Par Or Stated Value Per Share Common stock, shares authorized Common Stock Shares Authorized Common stock, shares issued Common Stock Shares Issued Common stock, shares outstanding Common Stock Shares Outstanding Change in fair value of preferred stock tranche obligation. Income Statement [Abstract] Operating expenses: Operating Expenses [Abstract] Research and development Research And Development Expense General and administrative General And Administrative Expense Total operating expenses Operating Expenses Loss from operations Operating Income Loss Interest income Investment Income Interest Change in fair value of preferred stock tranche obligation Change In Fair Value Of Preferred Stock Tranche Obligation Net loss Net Income Loss Cumulative dividends on convertible preferred stock Temporary Equity Dividends Adjustment Net loss attributable to common stockholders Net Income Loss Available To Common Stockholders Basic Net loss per common share—basic and diluted Earnings Per Share Basic And Diluted Weighted-average number of shares outstanding used in computing net loss per common share—basic and diluted Weighted Average Number Of Share Outstanding Basic And Diluted Net loss Unrealized (loss) gain on available-for-sale securities, net of tax Other Comprehensive Income Availableforsale Securities Adjustment Net Of Tax Portion Attributable To Parent Comprehensive loss Comprehensive Income Net Of Tax Temporary equity stock issued during period shares new issues. Temporary equity, stock issued during period, shares, conversion of convertible securities. Temporary equity, stock issued during period, value, conversion of convertible securities. Statement Of Stockholders Equity [Abstract] Equity Components Statement Equity Components [Axis] Equity Component Equity Component [Domain] Common Stock Common Stock [Member] Additional Paid-In Capital Additional Paid In Capital [Member] Accumulated Deficit Retained Earnings [Member] Accumulated Other Comprehensive Income (loss) Accumulated Other Comprehensive Income [Member] Sale of Stock Subsidiary Sale Of Stock [Axis] Sale of Stock Sale Of Stock Name Of Transaction [Domain] Initial Public Offering I P O [Member] Beginning Balance Temporary Equity, Beginning Balance, Shares Temporary Equity Shares Outstanding Temporary Equity, Beginning Balance Beginning Balance, Shares Shares Outstanding Issuance of convertible preferred stock, net of issuance costs and discount on allocation of proceeds to preferred stock tranche obligation Temporary Equity Stock Issued During Period Value New Issues Issuance of convertible preferred stock, net of issuance costs and discount on allocation of proceeds to preferred stock tranche obligation, Shares Temporary Equity Stock Issued During Period Shares New Issues Issuance of common stock upon the initial public offering, net Stock Issued During Period Value New Issues Issuance of common stock upon initial public offering, net of issuance costs, Shares Stock Issued During Period Shares New Issues Conversion of convertible preferred stock into common stock upon the initial public offering Stock Issued During Period Value Conversion Of Convertible Securities Temporary Equity, Conversion of convertible preferred stock into common stock upon initial public offering, Shares Temporary Equity Stock Issued During Period Shares Conversion Of Convertible Securities Temporary Equity, Conversion of convertible preferred stock into common stock upon initial public offering Temporary Equity Stock Issued During Period Value Conversion Of Convertible Securities Conversion of convertible preferred stock into common stock upon the initial public offering, Shares Stock Issued During Period Shares Conversion Of Convertible Securities Stock issued on exercise of stock options Stock Issued During Period Value Stock Options Exercised Stock issued on exercise of stock options, Shares Stock Issued During Period Shares Stock Options Exercised Stock-based compensation expense Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value Ending Balance Temporary Equity, Ending Balance, Shares Temporary Equity, Ending Balance Ending Balance, Shares Discount on allocation of proceeds to preferred stock tranche obligation. Series C convertible preferred stock. Series C Convertible Preferred Stock Series C Convertible Preferred Stock [Member] Offering and Issuance costs Payments Of Stock Issuance Costs Discount on allocation of proceeds to preferred stock tranche obligation Discount On Allocation Of Proceeds To Preferred Stock Tranche Obligation Increase (decrease) in prepaid expenses and other current and noncurrent assets. Deferred offering costs included in accounts payable and other current liabilities. Property and equipment purchases included in accounts payable. Statement Of Cash Flows [Abstract] Operating activities: Net Cash Provided By Used In Operating Activities [Abstract] Net loss Profit Loss Adjustments to reconcile net loss to net cash used in operating activities: Adjustments To Reconcile Net Income Loss To Cash Provided By Used In Operating Activities [Abstract] Stock-based compensation expense Share Based Compensation Depreciation Depreciation Change in fair value of preferred stock tranche obligation Accretion of premium and discounts on short-term investments Accretion Amortization Of Discounts And Premiums Investments Changes in operating assets and liabilities: Increase Decrease In Operating Capital [Abstract] Prepaid expenses and other current and non-current assets Increase Decrease In Prepaid Expenses And Other Current And Noncurrent Assets Accounts payable Increase Decrease In Accounts Payable Accrued research and development Increase Decrease In Accrued Liabilities Other current and non-current liabilities Increase Decrease In Other Operating Liabilities Net cash used in operating activities Net Cash Provided By Used In Operating Activities Investing activities: Net Cash Provided By Used In Investing Activities [Abstract] Purchases of property and equipment Payments To Acquire Property Plant And Equipment Purchases of short-term investments Payments To Acquire Short Term Investments Maturity of short-term investments Proceeds From Sale Maturity And Collection Of Shortterm Investments Net cash used in investing activities Net Cash Provided By Used In Investing Activities Financing activities: Net Cash Provided By Used In Financing Activities [Abstract] Proceeds from issuance of common stock upon initial public offering, net of underwriting discounts and commissions Proceeds From Issuance Of Common Stock Proceeds from issuance of convertible preferred stock, net of issuance costs Proceeds From Issuance Of Convertible Preferred Stock Proceeds from exercise of stock options Proceeds From Stock Options Exercised Payment of offering costs Net cash provided by financing activities Net Cash Provided By Used In Financing Activities Net increase in cash and cash equivalents Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect Cash and cash equivalents at beginning of period Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Including Disposal Group And Discontinued Operations Cash and cash equivalents at end of period Supplemental disclosure of noncash items: Cash Flow Noncash Investing And Financing Activities Disclosure [Abstract] Deferred offering costs included in accounts payable and other current liabilities Deferred Offering Costs Included In Accounts Payable And Other Current Liabilities Conversion of convertible preferred stock into common stock upon initial public offering Conversion Of Stock Amount Issued1 Property and equipment purchases included in accounts payable Property And Equipment Purchases Included In Accounts Payable Documents Incorporated by Reference Documents Incorporated By Reference [Text Block] Organization Consolidation And Presentation Of Financial Statements [Abstract] Organization Organization Consolidation And Presentation Of Financial Statements Disclosure [Text Block] Accounting Policies [Abstract] Summary of Significant Accounting Policies Significant Accounting Policies [Text Block] Fair Value Disclosures [Abstract] Fair Value Measurements Derivatives And Fair Value [Text Block] Balance Sheet Related Disclosures [Abstract] Balance Sheet Components Supplemental Balance Sheet Disclosures [Text Block] Commitments And Contingencies Disclosure [Abstract] Commitments and Contingencies Commitments And Contingencies Disclosure [Text Block] Temporary equity disclosure. Temporary Equity Disclosure [Abstract] Convertible Preferred Stock and Stockholders’ Equity (Deficit) Temporary Equity Disclosure [Text Block] Disclosure Of Compensation Related Costs Sharebased Payments [Abstract] Stock-Based Compensation Disclosure Of Compensation Related Costs Share Based Payments [Text Block] Income Tax Disclosure [Abstract] Income Taxes Income Tax Disclosure [Text Block] Compensation And Retirement Disclosure [Abstract] Employee Retirement Plan Pension And Other Postretirement Benefits Disclosure [Text Block] Earnings Per Share [Abstract] Net Loss Per Share Attributable to Common Stockholders Earnings Per Share [Text Block] Basis of Presentation Basis Of Accounting Policy Policy [Text Block] Use of Estimates Use Of Estimates Cash and Cash Equivalents Cash And Cash Equivalents Policy [Text Block] Investments Marketable Securities Policy Concentrations of Credit Risk and Off-balance Sheet Risk Concentration Risk Credit Risk Deferred Offering Costs Deferred Charges Policy [Text Block] Property and Equipment Property Plant And Equipment Policy [Text Block] Impairment of Long-lived Assets Impairment Or Disposal Of Long Lived Assets Policy [Text Block] Research and Development Expenses Research And Development Expense Policy Accrued research and development costs. Accrued Research and Development Costs Accrued Research And Development Costs Policy [Text Block] Patents costs. Patents Costs Patents Costs Policy [Text Block] Convertible Preferred Stock Stockholders Equity Note Redeemable Preferred Stock Issue Policy Preferred stock tranche obligation. Preferred Stock Tranche Obligation Preferred Stock Tranche Obligation Policy [Text Block] Stock-based Compensation Share Based Compensation Option And Incentive Plans Policy Income Taxes Income Tax Policy [Text Block] Net Loss Per Share Earnings Per Share Policy [Text Block] Related party transactions. Related Party Transactions Related Party Transactions Policy [Text Block] Segments Segment Reporting Policy Policy [Text Block] Comprehensive Loss Comprehensive Income Policy Policy [Text Block] Recently Adopted and Issued Accounting Pronouncements New Accounting Pronouncements Policy Policy [Text Block] Schedule of Property and Equipment and Depreciation Calculated using Straight-line Method over useful Life of Asset Property Plant And Equipment [Text Block] Schedule of Assets and Liabilities Measured at Fair Value on Recurring Basis Schedule Of Fair Value Assets And Liabilities Measured On Recurring Basis Table [Text Block] Summary of Company's Financial Assets Measured at Fair Value Fair Value Assets Measured On Recurring Basis [Text Block] Summary of Reconciliation of Level 3 Liabilities Measured at Fair Value Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Text Block] Schedule of Prepaid Expenses and Other Non-current Assets Deferred Costs Capitalized Prepaid And Other Assets Disclosure [Text Block] Schedule of Other Current Liabilities Other Current Liabilities Table [Text Block] Schedule of Future Minimum Lease Payments Schedule Of Future Minimum Rental Payments For Operating Leases Table [Text Block] Schedule of expense. Schedule of Expense under JHU Agreement Schedule Of Expense Table [Text Block] Summary of Outstanding Convertible Preferred Stock Temporary Equity Table [Text Block] Summary of Stock Option Activity Schedule Of Share Based Compensation Stock Options Activity Table [Text Block] Schedule of Assumptions Using Black-Scholes to Estimate Fair Value of Each Awards Schedule Of Share Based Payment Award Stock Options Valuation Assumptions Table [Text Block] Summary of Stock-Based Compensation Expense Schedule Of Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Text Block] Schedule of Reconciliation of Federal Statutory Income Tax Rate to Effective Income Tax Rate Schedule Of Effective Income Tax Rate Reconciliation Table [Text Block] Schedule of Components of Deferred Tax Assets Schedule Of Deferred Tax Assets And Liabilities Table [Text Block] Schedule of Reconciliation of Unrecognized Tax Benefits Schedule Of Unrecognized Tax Benefits Roll Forward Table [Text Block] Schedule of Basic and Diluted Net Loss Per Common Share Schedule Of Earnings Per Share Basic And Diluted Table [Text Block] Schedule of Anti-dilutive Securities Excluded from Calculation of Diluted Net Loss Per Share Schedule Of Antidilutive Securities Excluded From Computation Of Earnings Per Share [Text Block] Underwriting discounts and commissions. Common stock offering costs. Organization consolidation and presentation of financial statement. Organization consolidation and presentation of financial statements. Organization Consolidation And Presentation Of Financial Statements [Table] Organization Consolidation And Presentation Of Financial Statements [Table] Scenario Statement Scenario [Axis] Scenario Scenario Unspecified [Domain] Forecast Scenario Forecast [Member] Organization Consolidation And Presentation Of Financial Statements [Line Items] Organization Consolidation And Presentation Of Financial Statements [Line Items] Shares issued and sold, price per share Shares Issued Price Per Share Number of shares purchased in additional pursuant to underwriters' option Share Based Compensation Arrangement By Share Based Payment Award Shares Purchased For Award Net proceeds from shares issued Underwriting discounts and commissions Underwriting Discounts And Commissions Offering costs Common Stock Offering Costs Conversion of convertible preferred stock into common stock upon initial public offering Outstanding redeemable convertible preferred stock converted to common stock Convertible Preferred Stock Shares Issued Upon Conversion Reverse stock split, description Stockholders Equity Reverse Stock Split Reverse stock split Stockholders Equity Note Stock Split Conversion Ratio1 Accumulated deficit Tax Cuts and Jobs Act of 2017, percentage of income limitation on use of net operating losses. Income taxes receivable, net operating loss term, CARES Act. Income taxes receivable, net operating loss, CARES Act relief description. Tax Cuts and Jobs Act of 2017, percentage of income limitation on use of net operating losses Tax Cuts And Jobs Act Of Two Thousand Seventeen Percentage Of Income Limitation On Use Of Net Operating Losses Income taxes receivable, net operating loss term, CARES Act Income Taxes Receivable Net Operating Loss Term C A R E S Act Income taxes receivable, net operating loss, CARES Act Relief description Income Taxes Receivable Net Operating Loss C A R E S Act Relief Description Employee retention tax credit period start date. Employee retention tax credit period end date. Credit rate percent of qualified wages. Creditable wages limit per year. Creditable wages limit per quarter. Employee retention tax credit period, start date Employee Retention Tax Credit Period Start Date Employee retention tax credit period, end date Employee Retention Tax Credit Period End Date Credit rate percent of qualified wages Credit Rate Percent Of Qualified Wages Creditable wages limit per year Creditable Wages Limit Per Year Creditable wages limit per quarter Creditable Wages Limit Per Quarter Schedule Of Property Plant And Equipment [Table] Schedule Of Property Plant And Equipment [Table] Long-Lived Tangible Asset Property Plant And Equipment By Type [Axis] Long-Lived Tangible Asset Property Plant And Equipment Type [Domain] Manufacturing and laboratory equipment. Manufacturing and Laboratory Equipment Manufacturing And Laboratory Equipment [Member] Computer Hardware Computer Equipment [Member] Office Furniture and Equipment Office Equipment [Member] Statistical Measurement Range [Axis] Statistical Measurement Range [Member] Minimum Minimum [Member] Maximum Maximum [Member] Property Plant And Equipment [Line Items] Property Plant And Equipment [Line Items] Property and equipment useful life of asset Property Plant And Equipment Useful Life New Accounting Pronouncements Or Change In Accounting Principle [Table] New Accounting Pronouncements Or Change In Accounting Principle [Table] Income Statement Location Income Statement Location [Axis] Income Statement Location Income Statement Location [Domain] General and Administrative General And Administrative Expense [Member] Accounting Standards Update Adjustments For New Accounting Pronouncements [Axis] Accounting Standards Update Type Of Adoption [Member] Accounting Standards Update 2018-13 Accounting Standards Update201813 [Member] New Accounting Pronouncements Or Change In Accounting Principle [Line Items] New Accounting Pronouncements Or Change In Accounting Principle [Line Items] Impairment losses Impairment Of Long Lived Assets Held For Use Convertible preferred stock converted into common stock Shares outstanding Related party transaction, costs incurred Related Party Transaction Amounts Of Transaction Accounts payable, related parties Accounts Payable Related Parties Current Number of operating segment Number Of Operating Segments Change in accounting principle, accounting standards update, adopted Change In Accounting Principle Accounting Standards Update Adopted Change in accounting principle, accounting standards update, adoption date Change In Accounting Principle Accounting Standards Update Adoption Date Change in accounting principle, accounting standards update, immaterial effect Change In Accounting Principle Accounting Standards Update Immaterial Effect Short-term investment fair value disclosure. Debt Securities Available For Sale [Table] Debt Securities Available For Sale [Table] Fair Value Hierarchy and NAV Fair Value By Fair Value Hierarchy Level [Axis] Fair Value Hierarchy and NAV Fair Value Measurements Fair Value Hierarchy [Domain] Level 1 Fair Value Inputs Level1 [Member] Level 2 Fair Value Inputs Level2 [Member] Level 3 Fair Value Inputs Level3 [Member] Investment Type Investment Type [Axis] Investments Investment Type Categorization [Member] Corporate Debt Securities Corporate Debt Securities [Member] Commercial Paper Commercial Paper [Member] Government Agency Bonds U S Government Corporations And Agencies Securities [Member] Cash and Cash Equivalents Cash And Cash Equivalents [Axis] Cash and Cash Equivalents Restricted Cash And Cash Equivalents Cash And Cash Equivalents [Member] Money Market Funds Money Market Funds [Member] Preferred stock tranche obligation. Preferred Stock Tranche Obligation Preferred Stock Tranche Obligation [Member] Schedule Of Available For Sale Securities [Line Items] Schedule Of Available For Sale Securities [Line Items] Current assets: Assets Fair Value Disclosure [Abstract] Cash equivalents Cash And Cash Equivalents Fair Value Disclosure Short-term investments Short Term Investment Fair Value Disclosure Assets measured at fair value Assets Fair Value Disclosure Current liabilities: Liabilities Fair Value Disclosure [Abstract] Liabilities measured at fair value Liabilities Fair Value Disclosure Cash and cash equivalents fair value disclosure amortized cost basis. Short-term investment fair value disclosure amortized cost basis. Short-term investment fair value disclosure accumulated gross unrealized gain before tax. Short-term investment fair value disclosure accumulated gross unrealized loss before tax. Assets fair value disclosure amortized cost basis. Fair Value By Balance Sheet Grouping [Table] Fair Value By Balance Sheet Grouping [Table] Measurement Frequency Fair Value By Measurement Frequency [Axis] Measurement Frequency Fair Value Measurement Frequency [Domain] Fair Value, Recurring Fair Value Measurements Recurring [Member] Asset Class Fair Value By Asset Class [Axis] Asset Class Fair Value Assets Measured On Recurring Basis Unobservable Input Reconciliation By Asset Class [Domain] Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items] Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items] Total cash equivalents, Amortized Cost Cash And Cash Equivalents Fair Value Disclosure Amortized Cost Basis Total cash equivalents, Unrealized Gains Cash And Cash Equivalents Fair Value Disclosure Accumulated Gross Unrealized Gain Before Tax Total cash equivalents, Unrealized Losses Cash And Cash Equivalents Fair Value Disclosure Accumulated Gross Unrealized Loss Before Tax Total cash equivalents, Aggregate Fair Value Total short-term investments, Amortized Cost Short Term Investment Fair Value Disclosure Amortized Cost Basis Total short-term investments, Unrealized Gains Short Term Investment Fair Value Disclosure Accumulated Gross Unrealized Gain Before Tax Total short-term investments, Unrealized Losses Short Term Investment Fair Value Disclosure Accumulated Gross Unrealized Loss Before Tax Total short-term investments, Aggregate Fair Value Total asset measured at fair value, Amortized Cost Assets Fair Value Disclosure Amortized Cost Basis Total asset measured at fair value, Unrealized Gains Assets Fair Value Disclosure Accumulated Gross Unrealized Gain Before Tax Total asset measured at fair value, Unrealized Losses Assets Fair Value Disclosure Accumulated Gross Unrealized Loss Before Tax Total asset measured at fair value, Aggregate Fair Value Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Table] Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Table] Measurement Input Type Measurement Input Type [Axis] Measurement Input Type Measurement Input Type [Domain] Measurement Input, Stock Price Volatility Measurement Input Price Volatility [Member] Measurement Input, Risk Free Interest Rate Measurement Input Risk Free Interest Rate [Member] Measurement Input, Expected Dividend Payment Measurement Input Expected Dividend Payment [Member] Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] Other-than-temporary impairment losses Other Than Temporary Impairment Loss Debt Securities Available For Sale Recognized In Earnings Debt instrument expected term measurement input. Change in fair value Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Liability Gain Loss Included In Earnings Debt instrument measurement input Debt Instrument Measurement Input Debt Instrument, expected term measurement input Debt Instrument Expected Term Measurement Input Fair value measurement with unobservable inputs reconciliation recurring basis liability change in fair value and expiration of preferred stock tranche obligation. Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Table] Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Table] Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items] Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items] Fair value as of December 31, 2019 Fair Value Measurement With Unobservable Inputs Reconciliations Recurring Basis Liability Value Change in fair value and expiration of the preferred stock tranche obligation Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Liability Change In Fair Value And Expiration Of Preferred Stock Tranche Obligation Balance as of December 31, 2020 Fair value assets, level 1 to level 2 transfers, amount Fair Value Assets Level1 To Level2 Transfers Amount Fair value assets, level 2 to level 1 transfers, amount Fair Value Assets Level2 To Level1 Transfers Amount Fair value assets, transfers into level 3 Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Transfers Into Level3 Fair value liabilities, level 1 to Level 2 transfers amount Fair Value Liabilities Level1 To Level2 Transfers Amount Fair value liabilities, level 2 to Level 1 transfers amount Fair Value Liabilities Level2 To Level1 Transfers Amount Fair value liabilities, transfers into level 3 Fair Value Measurement With Unobservable Inputs Reconciliation Liability Transfers Into Level3 Prepaid clinical and research expenses noncurrent. Deferred offering costs noncurrent. Prepaid Expense And Other Assets Noncurrent [Abstract] Prepaid clinical and research expenses Prepaid Clinical And Research Expenses Noncurrent Deferred offering costs Deferred Offering Costs Noncurrent Deposits Deposits Assets Noncurrent Total prepaid expenses and other non-current assets Property Plant And Equipment [Abstract] Computer hardware. Computer Hardware Computer Hardware [Member] Office furniture and equipment. Office Furniture and Equipment Office Furniture And Equipment [Member] Leasehold Improvement Leasehold Improvements [Member] Construction in Progress Construction In Progress [Member] Property and equipment, at cost Property Plant And Equipment Gross Less: accumulated depreciation Accumulated Depreciation Depletion And Amortization Property Plant And Equipment Property and equipment, net Depreciation expense Other Liabilities Current [Abstract] Salaries and benefits Employee Related Liabilities Current Professional services Accrued Professional Fees Current Deferred rent Deferred Rent Credit Current Other Other Sundry Liabilities Current Total other current liabilities Contractual Obligation Term Loss Contingencies [Table] Loss Contingencies [Table] Category of Item Purchased Long Term Purchase Commitment By Category Of Item Purchased [Axis] Long-term Purchase Commitment, Category of Item Purchased Long Term Purchase Commitment Category Of Item Purchased [Domain] Research and Development Research And Development Arrangement [Member] Geographical Statement Geographical [Axis] Geographical Segment Geographical [Domain] Redwood City, California CALIFORNIA Baltimore, Maryland MARYLAND Collaborative Arrangement and Arrangement Other than Collaborative Type Of Arrangement [Axis] Collaborative Arrangement and Arrangement Other than Collaborative Arrangements And Nonarrangement Transactions [Member] License Agreement. License Agreement License Agreement [Member] Counterparty Name Counterparty Name [Axis] Counterparty Name Repurchase Agreement Counterparty Name [Domain] Johns Hopkins University. JHU Johns Hopkins University [Member] United States UNITED STATES Kala Agreement. Kala Agreement Kala Agreement [Member] AffaMed Letter. AffaMed Letter Affa Med Letter [Member] Loss Contingencies [Line Items] Loss Contingencies [Line Items] Contractual obligation Contractual Obligation Contractual obligation term Contractual Obligation Term Lessee operating lease maturity year and month. Operating lease, term Lessee Operating Lease Maturity Year And Month Rent expense Operating Lease Expense 2021 Operating Leases Future Minimum Payments Due Current 2022 Operating Leases Future Minimum Payments Due In Two Years 2023 Operating Leases Future Minimum Payments Due In Three Years Total future minimum lease payments Operating Leases Future Minimum Payments Due One-time, non-refundable fee payment. One-time, non-refundable fee One Time Non Refundable Fee Payment Percentage of royalty payments on net sales. Maximum credit percentage of running royalty rate. Aggregate amount payable upon developmental-related milestones for each product. Percentage of developmental milestone payment for second and third products. Percentage of royalty payments on net sales Percentage Of Royalty Payments On Net Sales Maximum credit percentage of running royalty rate Maximum Credit Percentage Of Running Royalty Rate Aggregate total amount of developmental milestone payment Aggregate Amount Payable Upon Developmental Related Milestones For Each Product Percentage of developmental milestone payment for second and third products Percentage Of Developmental Milestone Payment For Second And Third Products Research and Development Research And Development Expense [Member] Total JHU Agreement expense Percentage of minimum annual royalties including development milestone payments for first licensed product. Percentage of commercial milestone payments reduced. Development milestone payable under second licensed product. Development milestone payable under third licensed product. Development milestone payment extension period. Percentage of minimum annual royalties including development milestone payments for first licensed product Percentage Of Minimum Annual Royalties Including Development Milestone Payments For First Licensed Product Development milestone payment extension period Development Milestone Payment Extension Period Percentage of commercial milestone payments reduced Percentage Of Commercial Milestone Payments Reduced Development milestone payable under second licensed product Development Milestone Payable Under Second Licensed Product Development milestone payable under third licensed product Development Milestone Payable Under Third Licensed Product Operating expenses Accounts payable Option expiration period. Option expiration period Option Expiration Period Collaborative arrangement, description Collaborative Arrangement Rights And Obligations Temporary Equity By Class Of Stock [Table] Temporary Equity By Class Of Stock [Table] Series A convertible preferred stock. Series A Series A Convertible Preferred Stock [Member] Series A two convertible preferred stock. Series A-2 Series A Two Convertible Preferred Stock [Member] Series B convertible preferred stock. Series B Series B Convertible Preferred Stock [Member] Series C Temporary Equity [Line Items] Temporary Equity [Line Items] Shares Authorized Temporary Equity Shares Authorized Shares Outstanding Net Carrying Value Liquidation Preference Temporary Equity Liquidation Preference Temporary equity stock issued additional during period shares new issues. Temporary equity price per share. Temporary equity option to purchase additional shares period after notified. Fair value of preferred stock tranche obligation. Balance Sheet Location Balance Sheet Location [Axis] Balance Sheet Location Balance Sheet Location [Domain] Liabilities, current. Current Liability Liabilities Current [Member] Series B Preferred Series A Series C preferred, series B preferred and series A-2 preferred. Series C Preferred, Series B Preferred and Series A-2 Preferred Series C Preferred Series B Preferred And Series A Two Preferred [Member] Series A-2 preferred, series B preferred and series C preferred. Series A-2 Preferred, Series B Preferred and Series C Preferred Series A Two Preferred Series B Preferred And Series C Preferred [Member] Convertible preferred stock authorized to sell Convertible preferred stock, price per share Temporary Equity Par Or Stated Value Per Share Convertible preferred stock, shares issued Convertible preferred stock option to purchase additional shares Temporary Equity Stock Issued Additional During Period Shares New Issues Convertible preferred stock, price per share Temporary Equity Price Per Share Convertible preferred stock option to purchase additional shares after notified, period Temporary Equity Option To Purchase Additional Shares Period After Notified Fair value of preferred stock tranche obligation Fair Value Of Preferred Stock Tranche Obligation Dividends rights, amount per share on each outstanding share payable. Dividends rights, amount per share on each outstanding share payable Dividends Rights Amount Per Share On Outstanding Share Payable Dividends declared to-date Preferred Stock Dividends Per Share Declared Preferred stock, convertible, conversion price Debt Instrument Convertible Conversion Ratio1 Convertible preferred stock, price per share Temporary Equity Liquidation Preference Per Share Preferred stock voting rights Preferred Stock Voting Rights Common stock, voting rights Common Stock Voting Rights Percentage of aggregate number of shares of common stock outstanding on last day of preceding year added to plan. Schedule Of Share Based Compensation Arrangements By Share Based Payment Award [Table] Schedule Of Share Based Compensation Arrangements By Share Based Payment Award [Table] Plan Name Plan Name [Axis] Plan Name Plan Name [Domain] Two thousand and twenty equity incentive plan. 2020 Equity Incentive Plan Two Thousand And Twenty Equity Incentive Plan [Member] Two thousand and twenty employee stock purchase plan. 2020 Employee Stock Purchase Plan Two Thousand And Twenty Employee Stock Purchase Plan [Member] Award Type Award Type [Axis] Award Type Share Based Compensation Arrangements By Share Based Payment Award Award Type And Plan Name [Domain] Restricted Stock Units (RSUs) Restricted Stock Units R S U [Member] Share Based Compensation Arrangement By Share Based Payment Award [Line Items] Share Based Compensation Arrangement By Share Based Payment Award [Line Items] Common stock shares reserved for future issuance Common Stock Capital Shares Reserved For Future Issuance Percentage of aggregate number of shares of common stock outstanding on last day of preceding year added to plan Percentage Of Aggregate Number Of Shares Of Common Stock Outstanding On Last Day Of Preceding Year Added To Plan Number of additional awards grant Share Based Compensation Arrangement By Share Based Payment Award Number Of Shares Available For Grant Aggregate number of shares issued over the term of the ESPP Number of Options, Outstanding Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number Number of Options, Granted Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period Gross Number of Options, Exercised Forfeited and Canceled Share Based Compensation Arrangement By Share Based Payment Award Options Forfeitures In Period Number of Options, Outstanding Number of Options, Options Exercisable Share Based Compensation Arrangement By Share Based Payment Award Options Exercisable Number Weighted Average Exercise Price, Outstanding Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price Weighted Average Exercise Price, Granted Share Based Compensation Arrangements By Share Based Payment Award Options Grants In Period Weighted Average Exercise Price Weighted Average Exercise Price, Exercised Share Based Compensation Arrangements By Share Based Payment Award Options Exercises In Period Weighted Average Exercise Price Forfeited and Canceled Share Based Compensation Arrangements By Share Based Payment Award Options Forfeitures In Period Weighted Average Exercise Price Weighted Average Exercise Price, Outstanding Weighted Average Exercise Price, Options Exercisable Share Based Compensation Arrangement By Share Based Payment Award Options Exercisable Weighted Average Exercise Price Weighted Average Remaining Contractual Term, Outstanding Sharebased Compensation Arrangement By Sharebased Payment Award Options Outstanding Weighted Average Remaining Contractual Term2 Weighted Average Remaining Contractual Term, Options Exercisable Sharebased Compensation Arrangement By Sharebased Payment Award Options Exercisable Weighted Average Remaining Contractual Term1 Aggregate Intrinsic Value, Outstanding Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Intrinsic Value Aggregate Intrinsic Value, Options Exercisable Sharebased Compensation Arrangement By Sharebased Payment Award Options Exercisable Intrinsic Value1 Common stock shares reserved for future issuance Share Based Compensation Arrangement By Share Based Payment Award Options Exercises In Period Total Intrinsic Value Aggregate fair value of options vested Sharebased Compensation Arrangement By Sharebased Payment Award Options Vested In Period Fair Value1 Weighted average grant date fair value per share of options vested Sharebased Compensation Arrangement By Sharebased Payment Award Options Vested Weighted Average Grant Date Fair Value Share-based compensation arrangement by share-based payment award, equity instruments other than options, Shares issued during the period Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Grants In Period Weighted average grant date fair value Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Grants In Period Weighted Average Grant Date Fair Value Share-based compensation arrangement by share-based payment award, equity instruments other than options, vested Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Vested In Period Share-based compensation arrangement by share-based payment award, equity instruments other than options, forfeited Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Forfeited In Period Weighted-average grant date fair value per option granted Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period Weighted Average Grant Date Fair Value Expected term (years) Sharebased Compensation Arrangement By Sharebased Payment Award Fair Value Assumptions Expected Term1 Expected volatility Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Expected Volatility Rate Risk-free interest rate, minimum Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Risk Free Interest Rate Minimum Risk-free interest rate, maximum Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Risk Free Interest Rate Maximum Expected dividend Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Expected Dividend Rate Total stock-based compensation expense Allocated Share Based Compensation Expense Total unrecognized stock-based compensation expenses related to outstanding unvested stock awards Employee Service Share Based Compensation Nonvested Awards Total Compensation Cost Not Yet Recognized Stock Options Total unrecognized stock-based compensation expenses related to outstanding unvested stock options weighted-average term of recognition Employee Service Share Based Compensation Nonvested Awards Total Compensation Cost Not Yet Recognized Period For Recognition1 Accelerated vesting of unvested stock options Sharebased Compensation Arrangement By Sharebased Payment Award Accelerated Vesting Number Modification resulted in additional stock-based compensation Share Based Compensation Arrangement By Share Based Payment Award Accelerated Compensation Cost Effective income tax rate reconciliation mark to market gain or loss. Income taxes. Income Taxes [Abstract] Income tax benefit at the federal statutory rate Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate State income taxes, net of federal benefit Effective Income Tax Rate Reconciliation State And Local Income Taxes Research and development tax credits Effective Income Tax Rate Reconciliation Tax Credits Research Other Effective Income Tax Rate Reconciliation Other Adjustments Mark to market gain/loss Effective Income Tax Rate Reconciliation Mark To Market Gain Or Loss Change in valuation allowance Effective Income Tax Rate Reconciliation Change In Deferred Tax Assets Valuation Allowance Total Effective Income Tax Rate Continuing Operations Deferred income tax liabilities depreciation. Deferred tax assets Deferred Tax Assets Net [Abstract] Federal and state net operating loss carryforwards Deferred Tax Assets Operating Loss Carryforwards Research and development tax credits Deferred Tax Assets Tax Credit Carryforwards Research Other Deferred Tax Assets Other Gross deferred tax assets Deferred Tax Assets Gross Less: valuation allowance Deferred Tax Assets Valuation Allowance Total deferred tax assets Deferred Tax Assets Net Deferred tax liabilities Deferred Tax Liabilities Net [Abstract] Depreciation Deferred Income Tax Liabilities Depreciation Total deferred tax liabilities Deferred Income Tax Liabilities Net deferred tax assets Deferred Tax Assets Liabilities Net Income taxes line items. Income taxes. Income Taxes [Table] Income Taxes [Table] Income Tax Authority Income Tax Authority [Axis] Income Tax Authority Income Tax Authority [Domain] Federal Domestic Country [Member] State State And Local Jurisdiction [Member] Income Taxes [Line Items] Income Taxes [Line Items] Deferred tax assets increase in valuation allowance Income Tax Reconciliation Change In Deferred Tax Assets Valuation Allowance Operating loss carryforwards expiration beginning year. Tax credit carryforward expiration beginning year. Federal net operating loss carryforwards Deferred Tax Assets Operating Loss Carryforwards Domestic Tax credits Tax Credit Carryforward Amount Operating loss carryforwards expiration beginning year Operating Loss Carryforwards Expiration Beginning Year Tax credit carryforwards expiration beginning year Tax Credit Carryforward Expiration Beginning Year Net operating loss carryforwards, infinite life Deferred Tax Assets Operating Loss Carryforwards Not Subject To Expiration State NOLs Deferred Tax Assets Operating Loss Carryforwards State And Local Balance—beginning of year Unrecognized Tax Benefits Addition based on tax position related to current year Unrecognized Tax Benefits Increases Resulting From Current Period Tax Positions Addition based on tax position related to prior year Unrecognized Tax Benefits Increases Resulting From Prior Period Tax Positions Balance—end of year Contributions by employer Defined Contribution Plan Employer Discretionary Contribution Amount Cumulative dividends on convertible preferred stock Preferred Stock Dividends Income Statement Impact Schedule Of Antidilutive Securities Excluded From Computation Of Earnings Per Share [Table] Schedule Of Antidilutive Securities Excluded From Computation Of Earnings Per Share [Table] Antidilutive Securities Antidilutive Securities Excluded From Computation Of Earnings Per Share By Antidilutive Securities [Axis] Antidilutive Securities, Name Antidilutive Securities Name [Domain] Stock Options to Purchase Common Stock Employee Stock Option [Member] Restricted Stock Awards Restricted Stock [Member] Warrants to Purchase Common Stock Warrant [Member] Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items] Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items] Anti-dilutive securities excluded from calculation of diluted net loss per share Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount Convertible preferred stock could have been issued