Summary of Significant Accounting Policies and Recent Accounting Pronouncements (Policies)	12 Months Ended
Dec. 31, 2021
Accounting Policies [Abstract]
Basis of Presentation and Consolidation	Basis of Presentation and ConsolidationThe accompanying consolidated financial statements include the accounts of Lumos and its wholly-owned subsidiaries and have been prepared in accordance with accounting principles generally accepted in the U.S. (“U.S. GAAP”). All significant intercompany accounts and transactions are eliminated in consolidation. In the opinion of management, all adjustments of a normal and recurring nature considered necessary for a fair presentation have been included in the accompanying consolidated financial statements.
Use of Estimates	Use of Estimates The preparation of consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets, liabilities and expenses and the disclosure of contingent assets and liabilities in the Company’s financial statements and accompanying notes. Significant management estimates that affect the reported amounts of assets and liabilities include stock-based compensation, accruals for clinical trials and deferred tax assets. While we believe that the estimates and assumptions used in preparation of our consolidated financial statements based on our knowledge of current events and actions that we may undertake in the future are appropriate, actual results could differ from those estimates, and any such differences may be material.
Cash and Cash Equivalents	Cash and Cash Equivalents The Company considers cash, money market funds and all highly liquid investments with an original maturity of three months or less to be cash and cash equivalents. Cash and cash equivalents of $94.8 million and $98.7 million at December 31, 2021 and 2020, respectively, consist of balances in checking and money market accounts.
Property and Equipment	Property and Equipment Leasehold improvements and equipment are capitalized as the Company believes they have alternative future uses and are stated at cost. Depreciation on all leasehold improvements and equipment is calculated on the straight-line method over the shorter of the lease term or estimated useful life of the asset. Computer equipment has useful lives of three to five years. Long-lived assets are reviewed for impairment whenever changes in circumstances indicate that the carrying amount of an asset may not be recoverable. Recoverability of assets to be held and used is measured by a comparison of the carrying amount of an asset group to future net undiscounted cash flows expected to be generated by the asset group, primarily relating to proceeds for selling the assets. If such assets are considered to be impaired, the impairment to be recognized is measured at the amount by which the carrying amount of the assets exceeds the fair value of the assets. Assets to be disposed of are reported at the lower of the carrying amount or fair value less costs to sell.
Leases	LeasesThe Company determines if an arrangement is a lease at inception. Operating lease right-of-use (“ROU”) assets represent the Company’s right to use an underlying asset for the lease term and lease liabilities represent the Company’s obligation to make lease payments arising from the lease. Operating lease ROU assets and liabilities are recognized at commencement date based on the present value of lease payments over the lease term. The Company’s lease terms may include options to extend or terminate the lease when it is reasonably certain that the Company will exercise that option. Lease expenses for lease payments are recognized on a straight-line basis over the lease term.
Expenses Accrued Under Contractual Arrangements with Third Parties; Accrued Clinical Expenses	Expenses Accrued Under Contractual Arrangements with Third Parties; Accrued Clinical Expenses The Company estimates its accrued expenses through a process of reviewing open contracts and purchase orders, communicating with personnel to identify services that have been performed and estimating the level of service performed and the associated cost incurred for the service that may not be invoiced from the provider. The estimates of accrued expenses as of each balance sheet date are based on facts and circumstances known at that time. Such estimates are periodically confirmed with the service providers to verify accuracy. The Company bases its expenses related to clinical trials on estimates of the services received and efforts expended pursuant to contracts with multiple research institutions and contract research organizations that conduct and manage clinical trials on behalf of the Company. Invoicing from third-party contractors for services performed can lag several months. The Company accrues the costs of services rendered in connection with third-party contractor activities based on its estimate of management fees, site management and monitoring costs and data management costs as contracted. Differences between actual clinical trial costs and estimated clinical trial costs are adjusted for in the period in which they become known through operations. Accrued expenses as of December 31, 2021 were comprised of $2.8 million for compensation and related benefits, $0.5 million for clinical expenses, and $0.9 million for other accrued expenses. Accrued expenses as of December 31, 2020 were comprised of $3.3 million for compensation and related benefits, $0.2 million for clinical expenses, and $2.4 million for other accrued expenses.
Income Taxes	Income Taxes Income taxes are accounted for under the asset and liability method. Deferred tax assets and liabilities are recognized for the estimated future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases and operating loss and tax credit carryforwards. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. The effect on deferred tax assets and liabilities of a change in tax rates is recognized in operating results in the period that includes the enactment date. Management assesses the realizability of deferred tax assets and records a valuation allowance if it is more likely than not that all or a portion of the deferred tax assets will not be realized. The Company accounts for the effect of any uncertain tax positions based on a more likely than not threshold to the recognition of the tax positions being sustained based on the technical merits of the position under scrutiny by the applicable taxing authority. If a tax position or positions are deemed to result in uncertainties of those positions, the unrecognized tax position is estimated based on a cumulative probability assessment that aggregates the estimated tax liability for all uncertain tax positions. Interest and penalties assessed, if any, are recorded in its consolidated statement of operations in interest expense and other expenses.
Share-based Compensation	Share-Based Compensation Stock options and performance stock options The Company recognizes compensation costs related to stock options granted to employees and non-employees based on the estimated fair value of the awards on the date of grant. The Company estimates the grant date fair value, and the resulting stock-based compensation expense, using the Black-Scholes option-pricing model. The Company records forfeitures as they are incurred. The grant date fair value of the stock options is expensed on a straight-line basis over the applicable vesting period, which generally is four years. The fair value of performance-based stock options is recognized as compensation expense beginning at the time in which the performance conditions are deemed probable of achievement, over the remaining requisite service period. The assumptions used in Black-Scholes option-pricing model are as follows: •Exercise price. If Incentive Stock Options are granted to a 10% stockholder in the Company, the exercise price shall not be less than 110% of the common stock’s fair market value on the date of grant. •Fair Market Value of Common Stock. As Private Lumos’ common stock has not historically been publicly traded, Private Lumos has periodically estimated the fair market value of common stock after considering, among other things, contemporaneous valuations of its common and preferred stock prepared by unrelated third-party valuation firms in accordance with the guidance provided by the American Institute of Certified Public Accountants 2013 Practice Aid, Valuation of Privately-Held-Company Equity Securities Issued as Compensation. Subsequent to the Merger, the grant date fair market value is the quoted market price of the Company's common stock. •Expected term. The expected term of stock options represents the period that the stock options are expected to remain outstanding and is based on vesting terms, exercise term and contractual lives of the options. The expected term is based on the simplified method and is estimated as the average of the weighted average vesting term and the time to expiration as of the grant date. •Expected volatility. As the Company does not have sufficient historical stock price information to meet the expected life of the stock option grants, it uses a blended volatility based on the trading history from the common stock of a set of comparable publicly-listed biopharmaceutical companies. Volatility for employee stock purchase plan (“ESPP”) shares is equal to the Company’s historical volatility over the six-month offering period. •Risk-free interest rate. The risk-free interest rate is based on the U.S. Treasury yield with a maturity equal to the expected term of the stock options in effect at the time of grant. •Dividend yield. The expected dividend is assumed to be zero as the Company has never paid dividends and has no current plan to pay any dividends on its common stock. Restricted stock units Service-based restricted stock units are valued using the market price of our common stock on the grant date. The grant date fair value of the restricted stock units is expensed on a straight-line basis over the applicable vesting period, which generally is four years. Employee stock purchase plan Our ESPP allows employees to purchase common stock at a 15% discount from the lower of the common stock closing price on the first or last day of the offering period. The current offering period is from July 1, 2021 to June 30, 2023. We use the Black-Scholes Model to determine fair value, which incorporates assumptions as described above. The grant date fair value of the ESPP is expensed on a straight-line basis over the applicable vesting period, which generally is six months.
Financial Instruments	Financial Instruments and Concentrations of Credit Risk The Company determines the fair value of financial and non-financial assets and liabilities using the fair value hierarchy, which establishes three levels of inputs that may be used to measure fair value, as follows: •Level I: Inputs which include quoted prices in active markets for identical assets and liabilities. •Level II: Inputs other than Level I that are observable, either directly or indirectly, such as quoted prices for similar assets or liabilities; quoted prices in markets that are not active; or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities. •Level III: Unobservable inputs that are supported by little or no market activity and that are significant to the fair value of the assets or liabilities. Cash and cash equivalents, including balances in money market funds (Level I), receivables, and accounts payable are recorded at cost, which approximates fair value based on the short-term nature of these financial instruments. The Company is unable to estimate the fair value of the royalty obligation to Iowa Economic Development Authority based on future product sales, as the timing of payments, if any, is uncertain.
Concentration of Credit Risk	Financial instruments that potentially subject the Company to concentrations of credit risk consist primarily of cash and cash equivalents. Cash and cash equivalents are held by financial institutions and are federally insured up to certain limits. At times, the Company’s cash and cash equivalents balance exceeds the federally insured limits. To limit the credit risk, the Company invests its excess cash primarily in high quality securities such as money market funds.
Net Loss Per Share	Net Loss Per ShareBasic net loss per share is computed by dividing net loss applicable to common stockholders by the weighted average number of common shares outstanding during the period, without consideration for common stock equivalents. Diluted net loss per share reflects the potential dilution, using the treasury stock method.
Revenue Recognition	Revenue RecognitionRevenue is recognized when control of the promised goods is transferred to the customer in an amount that reflects the consideration to which the Company expects to be entitled in exchange for those products.
Research and Development Costs	Research and Development Costs Research and development costs are expensed as incurred. Research and development expenses consist primarily of employee-related expenses, which include salaries, bonuses, benefits and share-based compensation; manufacturing-related costs; clinical trial expenses which include expenses incurred under agreements with contract research organizations, investigative sites and consultants that conduct our clinical trials; facilities, depreciation of fixed assets and other allocated expenses, which include direct and allocated expenses for rent and maintenance of research facilities and equipment; license fees for and milestone payments related to in-licensed products and technology; and costs associated with non-clinical activities and regulatory approvals. Advance payments for goods or services to be rendered in the future for use in research and development activities are deferred and recorded as a prepaid asset. The deferred amounts are expensed as the related goods are delivered or the services are performed.
Patents	Patents The Company generally applies for patent protection on processes and products. Patent application costs are expensed as incurred as a component of general and administrative expense, as recoverability of such expenditures is uncertain.
Recently Adopted Accounting Standards	Recently Adopted Accounting Standards From time to time, new accounting pronouncements are issued by the FASB or other standard setting bodies and adopted by us as of a specified effective date, if applicable to us. In December 2019, the FASB issued ASU 2019-12, Income Taxes (“ASC 740”), which simplifies the accounting for income taxes by eliminating certain exceptions to the guidance in ASC 740 related to the approach for intra-period tax allocation, the methodology for calculating income taxes in an interim period and the recognition of deferred tax liabilities for outside basis differences. The new guidance also simplifies aspects of the accounting for franchise taxes and enacted changes in tax laws or rates and clarifies the accounting for transactions that result in a step-up in the tax basis of goodwill. The guidance is effective for calendar-year public business entities in 2021 and interim periods within that year.

Summary of Significant Accounting Policies and Recent Accounting Pronouncements (Policies)

12 Months Ended

Dec. 31, 2021

Basis of Presentation and ConsolidationThe accompanying consolidated financial statements include the accounts of Lumos and its wholly-owned subsidiaries and have been prepared in accordance with accounting principles generally accepted in the U.S. (“U.S. GAAP”). All significant intercompany accounts and transactions are eliminated in consolidation. In the opinion of management, all adjustments of a normal and recurring nature considered necessary for a fair presentation have been included in the accompanying consolidated financial statements.

Use of Estimates

The preparation of consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets, liabilities and expenses and the disclosure of contingent assets and liabilities in the Company’s financial statements and accompanying notes. Significant management estimates that affect the reported amounts of assets and liabilities include stock-based compensation, accruals for clinical trials and deferred tax assets. While we believe that the estimates and assumptions used in preparation of our consolidated financial statements based on our knowledge of current events and actions that we may undertake in the future are appropriate, actual results could differ from those estimates, and any such differences may be material.

Cash and Cash Equivalents

The Company considers cash, money market funds and all highly liquid investments with an original maturity of three months or less to be cash and cash equivalents. Cash and cash equivalents of $94.8 million and $98.7 million at December 31, 2021 and 2020, respectively, consist of balances in checking and money market accounts.

Property and Equipment

Leasehold improvements and equipment are capitalized as the Company believes they have alternative future uses and are stated at cost. Depreciation on all leasehold improvements and equipment is calculated on the straight-line method over the shorter of the lease term or estimated useful life of the asset. Computer equipment has useful lives of three to five years.

Long-lived assets are reviewed for impairment whenever changes in circumstances indicate that the carrying amount of an asset may not be recoverable. Recoverability of assets to be held and used is measured by a comparison of the carrying amount of an asset group to future net undiscounted cash flows expected to be generated by the asset group, primarily relating to proceeds for selling the assets. If such assets are considered to be impaired, the impairment to be recognized is measured at the amount by which the carrying amount of the assets exceeds the fair value of the assets. Assets to be disposed of are reported at the lower of the carrying amount or fair value less costs to sell.

Leases

LeasesThe Company determines if an arrangement is a lease at inception. Operating lease right-of-use (“ROU”) assets represent the Company’s right to use an underlying asset for the lease term and lease liabilities represent the Company’s obligation to make lease payments arising from the lease. Operating lease ROU assets and liabilities are recognized at commencement date based on the present value of lease payments over the lease term. The Company’s lease terms may include options to extend or terminate the lease when it is reasonably certain that the Company will exercise that option. Lease expenses for lease payments are recognized on a straight-line basis over the lease term.

Expenses Accrued Under Contractual Arrangements with Third Parties; Accrued Clinical Expenses

The Company estimates its accrued expenses through a process of reviewing open contracts and purchase orders, communicating with personnel to identify services that have been performed and estimating the level of service performed and the associated cost incurred for the service that may not be invoiced from the provider. The estimates of accrued expenses as of each balance sheet date are based on facts and circumstances known at that time. Such estimates are periodically confirmed with the service providers to verify accuracy.

The Company bases its expenses related to clinical trials on estimates of the services received and efforts expended pursuant to contracts with multiple research institutions and contract research organizations that conduct and manage clinical trials on behalf of the Company. Invoicing from third-party contractors for services performed can lag several months. The Company accrues the costs of services rendered in connection with third-party contractor activities based on its estimate of management fees, site management and monitoring costs and data management costs as contracted. Differences between actual clinical trial costs and estimated clinical trial costs are adjusted for in the period in which they become known through operations.

Accrued expenses as of December 31, 2021 were comprised of $2.8 million for compensation and related benefits, $0.5 million for clinical expenses, and $0.9 million for other accrued expenses. Accrued expenses as of December 31, 2020 were comprised of $3.3 million for compensation and related benefits, $0.2 million for clinical expenses, and $2.4 million for other accrued expenses.

Income Taxes

Income taxes are accounted for under the asset and liability method. Deferred tax assets and liabilities are recognized for the estimated future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases and operating loss and tax credit carryforwards. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. The effect on deferred tax assets and liabilities of a change in tax rates is recognized in operating results in the period that includes the enactment date. Management assesses the realizability of deferred tax assets and records a valuation allowance if it is more likely than not that all or a portion of the deferred tax assets will not be realized.

The Company accounts for the effect of any uncertain tax positions based on a more likely than not threshold to the recognition of the tax positions being sustained based on the technical merits of the position under scrutiny by the applicable taxing authority. If a tax position or positions are deemed to result in uncertainties of those positions, the unrecognized tax position is estimated based on a cumulative probability assessment that aggregates the estimated tax liability for all uncertain tax positions. Interest and penalties assessed, if any, are recorded in its consolidated statement of operations in interest expense and other expenses.

Share-based Compensation

Share-Based Compensation

Stock options and performance stock options

The Company recognizes compensation costs related to stock options granted to employees and non-employees based on the estimated fair value of the awards on the date of grant. The Company estimates the grant date fair value, and the resulting stock-based compensation expense, using the Black-Scholes option-pricing model. The Company records forfeitures as they are incurred. The grant date fair value of the stock options is expensed on a straight-line basis over the applicable vesting period, which generally is four years. The fair value of performance-based stock options is recognized as compensation expense beginning at the time in which the performance conditions are deemed probable of achievement, over the remaining requisite service period. The assumptions used in Black-Scholes option-pricing model are as follows:

•Exercise price. If Incentive Stock Options are granted to a 10% stockholder in the Company, the exercise price shall not be less than 110% of the common stock’s fair market value on the date of grant.

•Fair Market Value of Common Stock. As Private Lumos’ common stock has not historically been publicly traded, Private Lumos has periodically estimated the fair market value of common stock after considering, among other things, contemporaneous valuations of its common and preferred stock prepared by unrelated third-party valuation firms in accordance with the guidance provided by the American Institute of Certified Public Accountants 2013

Practice Aid, Valuation of Privately-Held-Company Equity Securities Issued as Compensation. Subsequent to the Merger, the grant date fair market value is the quoted market price of the Company's common stock.

•Expected term. The expected term of stock options represents the period that the stock options are expected to remain outstanding and is based on vesting terms, exercise term and contractual lives of the options. The expected term is based on the simplified method and is estimated as the average of the weighted average vesting term and the time to expiration as of the grant date.

•Expected volatility. As the Company does not have sufficient historical stock price information to meet the expected life of the stock option grants, it uses a blended volatility based on the trading history from the common stock of a set of comparable publicly-listed biopharmaceutical companies. Volatility for employee stock purchase plan (“ESPP”) shares is equal to the Company’s historical volatility over the six-month offering period.

•Risk-free interest rate. The risk-free interest rate is based on the U.S. Treasury yield with a maturity equal to the expected term of the stock options in effect at the time of grant.

•Dividend yield. The expected dividend is assumed to be zero as the Company has never paid dividends and has no current plan to pay any dividends on its common stock.

Restricted stock units

Service-based restricted stock units are valued using the market price of our common stock on the grant date. The grant date fair value of the restricted stock units is expensed on a straight-line basis over the applicable vesting period, which generally is four years.

Employee stock purchase plan

Our ESPP allows employees to purchase common stock at a 15% discount from the lower of the common stock closing price on the first or last day of the offering period. The current offering period is from July 1, 2021 to June 30, 2023. We use the Black-Scholes Model to determine fair value, which incorporates assumptions as described above. The grant date fair value of the ESPP is expensed on a straight-line basis over the applicable vesting period, which generally is six months.

Financial Instruments

Financial Instruments and Concentrations of Credit Risk

The Company determines the fair value of financial and non-financial assets and liabilities using the fair value hierarchy, which establishes three levels of inputs that may be used to measure fair value, as follows:

•Level I: Inputs which include quoted prices in active markets for identical assets and liabilities.

•Level II: Inputs other than Level I that are observable, either directly or indirectly, such as quoted prices for similar assets or liabilities; quoted prices in markets that are not active; or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities.

•Level III: Unobservable inputs that are supported by little or no market activity and that are significant to the fair value of the assets or liabilities.

Cash and cash equivalents, including balances in money market funds (Level I), receivables, and accounts payable are recorded at cost, which approximates fair value based on the short-term nature of these financial instruments. The Company is unable to estimate the fair value of the royalty obligation to Iowa Economic Development Authority based on future product sales, as the timing of payments, if any, is uncertain.

Concentration of Credit Risk

Financial instruments that potentially subject the Company to concentrations of credit risk consist primarily of cash and cash equivalents. Cash and cash equivalents are held by financial institutions and are federally insured up to certain limits. At times, the Company’s cash and cash equivalents balance exceeds the federally insured limits. To limit the credit risk, the Company invests its excess cash primarily in high quality securities such as money market funds.

Net Loss Per Share

Net Loss Per ShareBasic net loss per share is computed by dividing net loss applicable to common stockholders by the weighted average number of common shares outstanding during the period, without consideration for common stock equivalents. Diluted net loss per share reflects the potential dilution, using the treasury stock method.

Revenue Recognition

Revenue RecognitionRevenue is recognized when control of the promised goods is transferred to the customer in an amount that reflects the consideration to which the Company expects to be entitled in exchange for those products.

Research and Development Costs

Research and development costs are expensed as incurred. Research and development expenses consist primarily of employee-related expenses, which include salaries, bonuses, benefits and share-based compensation; manufacturing-related costs; clinical trial expenses which include expenses incurred under agreements with contract research organizations, investigative sites and consultants that conduct our clinical trials; facilities, depreciation of fixed assets and other allocated expenses, which include direct and allocated expenses for rent and maintenance of research facilities and equipment; license fees for and milestone payments related to in-licensed products and technology; and costs associated with non-clinical activities and regulatory approvals. Advance payments for goods or services to be rendered in the future for use in research and development activities are deferred and recorded as a prepaid asset. The deferred amounts are expensed as the related goods are delivered or the services are performed.

Patents

The Company generally applies for patent protection on processes and products. Patent application costs are expensed as incurred as a component of general and administrative expense, as recoverability of such expenditures is uncertain.

Recently Adopted Accounting Standards

From time to time, new accounting pronouncements are issued by the FASB or other standard setting bodies and adopted by us as of a specified effective date, if applicable to us.

In December 2019, the FASB issued ASU 2019-12, Income Taxes (“ASC 740”), which simplifies the accounting for income taxes by eliminating certain exceptions to the guidance in ASC 740 related to the approach for intra-period tax allocation, the methodology for calculating income taxes in an interim period and the recognition of deferred tax liabilities for outside basis differences. The new guidance also simplifies aspects of the accounting for franchise taxes and enacted changes in tax laws or rates and clarifies the accounting for transactions that result in a step-up in the tax basis of goodwill. The guidance is effective for calendar-year public business entities in 2021 and interim periods within that year.