Summary of Significant Accounting Policies

12 Months Ended

Dec. 31, 2021

Accounting Policies [Abstract]

Summary of Significant Accounting Policies

2. Summary of Significant Accounting Policies

Basis of Presentation

The accompanying financial statements have been prepared in accordance with accounting principles generally accepted in the United States (“GAAP”). Any reference in these notes to applicable guidance is meant to refer to GAAP as found in the Accounting Standards Codification (“ASC”) and Accounting Standards Updates (“ASU”) promulgated by the Financial Accounting Standards Board (“FASB”).

Use of Estimates

The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported balances of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of expenses during the reporting period. Estimates are used for, but not limited to, stock-based compensation, derivative liability, the timing of research and development accruals, and income taxes. Although these estimates are based on the Company’s knowledge of current events and actions it may undertake in the future, actual results may materially differ from these estimates and assumptions.

The full extent to which the COVID-19 pandemic will directly or indirectly impact the Company’s business, results of operations and financial condition, including expenses, clinical trials and research and development costs, will depend on future developments that are highly uncertain, including as a result of new information that may emerge concerning COVID-19 and the actions taken to contain or treat COVID-19, as well as the economic impact on local, regional, national and international markets. The Company has considered potential impacts arising from the COVID-19 pandemic and is not presently aware of any events or circumstances that would require the Company to update its estimates, judgments or revise the carrying value of its assets or liabilities.

Concentration of Credit Risk

Financial instruments which potentially subject the Company to significant concentration of credit risk consist of cash and restricted cash. The Company is exposed to credit risk from its deposits of cash in excess of amounts insured by the Federal Deposit Insurance Corporation. The Company maintains an Insured Cash Sweep account where balances are maintained in interest bearing demand accounts. The Company has not experienced any losses on its deposits of cash since inception, and management believes that the Company is not exposed to significant credit risk due to the financial positions of the respective depository institutions in which those deposits are held.

Comprehensive Loss

Comprehensive loss is defined as a change in equity during a period from transactions and other events and circumstances from non-owner sources. The Company’s comprehensive loss was the same as its reported net loss for all periods presented.

Fair Value of Financial Instruments

The accounting guidance defines fair value, establishes a consistent framework for measuring fair value, and expands disclosure for each major asset and liability category measured at fair value on either a recurring or nonrecurring basis. Fair value is defined as an exit price representing the amount that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants. As such, fair value is a market-based measurement that should be determined based on assumptions that market participants would use in pricing an asset or liability.

The carrying amounts of all cash, restricted cash, prepaid expenses and other assets, accounts payable, and accrued and other current liabilities are considered to be representative of their respective fair values due to their short maturities.

The carrying values of the derivative liability of $1.6 million (level 3 fair value) and the convertible promissory note of $4.9 million in the accompanying balance sheet at December 31, 2020 approximate fair value because they collectively converted into 2,805,850 shares of Series B convertible preferred stock in March 2021.

Cash

Cash represents funds in the Company’s operating bank account. The Company has no cash equivalents.

Restricted Cash

The Company’s restricted cash includes payments received under the Grant Agreement (as defined in Note 4) with the Bill & Melinda Gates Foundation (“BMGF”) under which the Company was awarded a grant of up to $10.0 million. The Company will utilize the Grant Agreement funds as it incurs expenses for services performed under the agreement. Restricted cash also includes cash collateral supporting the standby letter of credit discussed in "Leases" below.

Property and equipment, net

Property and equipment, net is stated at cost, net of accumulated depreciation and is depreciated using the straight-line method over the estimated useful lives of the assets (generally two to five years).

Impairment of Long-Lived Assets

The Company regularly reviews the carrying value and estimated lives of its long-lived assets, including property and equipment to determine whether indicators of impairment may exist which warrant adjustments to carrying values or estimated useful lives. Should an impairment exist, the impairment loss would be measured based on the excess over the carrying amount of the asset’s fair value. The Company has not recognized any impairment losses from inception through December 31, 2021.

Derivative Liability, Convertible Notes Discount and Amortization

The Company’s convertible note (see Note 7) had conversion and redemption features that met the definition of an embedded derivative and were therefore subject to bifurcation and derivative accounting. The initial recognition of the fair value of the derivative resulted in a discount to the convertible note, with a corresponding derivative liability. The discount to the convertible note was amortized using the effective interest method. The amortization of the discount is included in interest and other income (expense) in the statements of operations and comprehensive loss. The derivative liability related to these features was recorded at estimated fair value and remeasured on a recurring basis. Any changes in fair value were reflected as change in fair value of derivative liability in the statements of operations and comprehensive loss at each reporting date while such instruments were outstanding. The derivative liability was settled in March 2021 upon conversion of the underlying convertible note into Series B convertible preferred stock, resulting in a loss on extinguishment of convertible promissory note.

Leases

At the inception of a contractual arrangement, the Company determines whether the contract contains a lease by assessing whether there is an identified asset and whether the contract conveys the right to control the use of the identified asset in exchange for consideration over a period of time. If both criteria are met, the Company records the associated lease liability and corresponding right-of-use asset upon commencement of the lease using the implicit rate or a discount rate based on a credit-adjusted secured borrowing rate commensurate with the term of the lease. The Company additionally evaluates leases at their inception to determine if they are to be accounted for as an operating lease or a finance lease. A lease is accounted for as a finance lease if it meets one of the following five criteria: the lease has a purchase option that is reasonably certain of being exercised, the present value of the future cash flows is substantially all of the fair market value of the underlying asset, the lease term is for a significant portion of the remaining economic life of the underlying asset, the title to the underlying asset transfers at the end of the lease term, or if the underlying asset is of such a specialized nature that it is expected to have no alternative uses to the lessor at the end of the term. Leases that do not meet the finance lease criteria are accounted for as an operating lease. Operating lease assets represent a right to use an underlying asset for the lease term and operating lease liabilities represent an obligation to make lease payments arising from the lease. Operating lease liabilities with a term greater than one year and their corresponding right-of-use assets are recognized on the balance sheet at the commencement date of the lease based on the present value of lease payments over the expected lease term. Certain adjustments to the right-of-use asset may be required for items such as initial direct costs paid or incentives received. As the Company’s leases do not typically provide an implicit rate, the Company utilizes the appropriate incremental borrowing rate, determined as the rate of interest that the Company would have to pay to borrow on a collateralized basis over a similar term and in a similar economic environment. Lease cost is recognized on a straight-line basis over the lease term and variable lease payments are recognized as operating expenses in the period in which the obligation for those payments is incurred. Variable lease payments primarily include common area maintenance, utilities, real estate taxes, insurance, and other operating costs that are passed on from the lessor in proportion to the space leased by the Company. The Company has elected the practical expedient to not separate lease and non-lease components.

In January 2020, and amended in March 2020, the Company entered into a lab license agreement for office and lab space in Seattle, Washington. The lab license agreement is twelve months and provides for renewal options. The monthly base rent is approximately $16,000. The lab license agreement is considered short-term and therefore, no right-of-use asset or lease liability has been recorded.

In December 2021, the Company entered into a lease agreement for corporate office and lab space in Seattle, Washington. The Company took possession of certain leased space at various dates in January 2022 and March 2022. The lease agreement is five years and 3 months and provides for a one-time option to extend for a period of five additional years. The monthly base rent will be $0.2 million for the first year and will increase by 3.0% per year over the initial term. In addition, the Company is obligated to pay for common area maintenance and other costs. Under the terms of the lease agreement, the Company is required to maintain a standby letter of credit of $1.1 million at the execution of the lease agreement, reduced to $0.9 million at the first anniversary, and further reduced to $0.7 million at the second anniversary of the lease. As of December 31, 2021, the Company had not taken control of the space and the lease term had not commenced; therefore, no right-of-use asset or lease liability has been recognized.

Grant Revenue

The Company’s revenue consists of revenue under its Grant Agreement with BMGF (see Note 4). The Company is reimbursed for certain costs that support development activities, including the Company’s clinical trial notification (“CTN”) preparations for and planned first-in-human Phase 1/2 clinical trial of COVID-19 RBD VLP vaccine in Australia. The Company’s Grant Agreement does not provide a direct economic benefit to BMGF. Rather, the Company entered into an agreement with BMGF to make a certain amount of any resulting vaccine available and accessible at affordable pricing to people in certain low- and middle-income countries. The Company assessed this cost reimbursement agreement to determine if the agreement should be accounted for as an exchange transaction or a contribution. Such an agreement is accounted for as a contribution if the resource provider does not receive commensurate value in return for the assets transferred. Contributions are recognized as grant revenue when all donor-imposed conditions have been met. As BMGF ultimately determines if milestones under the agreement are met and if funding should continue, there may be a difference in timing between when research and development expenses are incurred and when grant revenue is recognized.

Accrued Research and Development Expense

The Company is required to estimate its obligation for expenses incurred under contracts with vendors, consultants, and contract research organizations, in connection with conducting research and development activities. The financial terms of these contracts are subject to negotiations, which vary from contract to contract and may result in payment flows that do not match the periods over which materials or services are provided under such contracts. The Company reflects research and development expenses in its financial statements by recognizing those expenses in the periods in which services and efforts are expended. The Company accounts for these expenses according to the progress of the preclinical study or clinical trial, as measured by the timing of various aspects of the study, trial or related activities. The Company determines accrual estimates through review of the underlying contracts along with preparation of financial models taking into account discussions with research and other key personnel and third-party service providers as to the progress of studies or trials, or other services being conducted. To date, the Company has had no material differences between its estimates of such expenses and the amounts actually incurred. During the course of a study or trial, the Company adjusts its expense recognition if actual results differ from its estimate. Nonrefundable advance payments for goods and services, including fees for process development or manufacturing and distribution of clinical supplies that will be used in future research and development activities, are deferred and recognized as expense in the period that the related goods are consumed or services are performed.

Research and Development

Research and development costs are expensed as incurred and consist primarily of external and internal costs related to the development of vaccine candidates, including salaries and benefits, stock-based compensation, facilities and depreciation, contracted research, consulting arrangements, and other expenses incurred to sustain the Company’s research and development programs.

Interest Income

Interest income consists of interest income earned on interest bearing demand accounts.

Liability for Early Exercise of Stock Options

Certain individuals were granted the ability to early exercise their stock options. The shares of common stock issued from the early exercise of unvested stock options are restricted and continue to vest in accordance with the original vesting schedule. The Company has the option to repurchase any unvested shares at the original purchase price upon any voluntary or involuntary termination. The shares purchased by the employees and non-employees pursuant to the early exercise of stock options are not deemed, for accounting purposes, to be outstanding until those shares vest. The cash received in exchange for exercised and unvested shares related to stock options granted is recorded as a liability for the early exercise of stock options on the accompanying balance sheets and will be reclassified as common stock and additional paid-in capital as the shares vest. Unvested shares issued under early exercise provisions subject to repurchase by the Company totaled 253,824 and 488,226 shares as of December 31, 2021 and 2020, respectively. As of December 31, 2021 and 2020, the Company had $0.2 million and $0.2 million respectively, of amounts related to shares issued with repurchase rights classified as other noncurrent liabilities in the accompanying balance sheets.

Stock-Based Compensation

Stock-based compensation expense represents the cost of the grant date fair value of employee, officer, director and non-employee stock option grants, estimated in accordance with the applicable accounting guidance, recognized on a straight-line basis over the vesting period. The vesting period generally approximates the expected service period of the awards. The Company recognizes forfeitures as they occur.

The Black-Scholes option pricing model uses inputs which are assumptions that generally require judgment. These assumptions include:

▪Fair Value of Common Stock. Prior to the Company’s IPO, the grant date fair market value of the shares of common stock underlying stock options was historically determined by the Company’s board of directors. Because there was no public market for the Company’s common stock, the board of directors exercised reasonable judgment and considered a number of objective and subjective factors to determine the best estimate of the fair market value, which included contemporaneous valuations performed by an independent third-party, the Company’s results of operations and financial position, including its levels of available capital resources, its stage of development and material risks related to the Company’s business, progress of the Company’s research and development activities, the Company’s business conditions and projections, the lack of marketability of the Company’s common stock and preferred stock as a private company, the prices at which the Company sold shares of its convertible preferred stock to outside investors in arms-length transactions, the rights, preferences and privileges of the Company’s redeemable convertible preferred stock relative to those of its common stock, the analysis of initial public offerings and the market performance of similar companies in the biopharmaceutical industry, the likelihood of achieving a liquidity event for the Company’s securityholders, such as an initial public offering or a sale of the Company, given prevailing market conditions, the hiring of key personnel and the experience of management, trends and developments in the Company’s industry, and external market conditions affecting the life sciences and biopharmaceutical industry sectors. Subsequent to the Company’s IPO, the grant date fair value of the Company’s common stock is determined based on its closing price.

▪Expected Term. The expected term represents the period that the options granted are expected to be outstanding. The expected term of stock options issued is determined using the simplified method (based on the average of the vesting term and the original contractual term) as the Company has concluded that its stock option exercise history does not provide a reasonable basis upon which to estimate expected term.

▪Expected Volatility. Given the Company’s limited historical stock price volatility data, the Company derived the expected volatility from the average historical volatilities over a period approximately equal to the expected term of comparable publicly traded companies within the Company’s peer group that were deemed to be representative of future stock price trends as the Company has limited trading history for its common stock. The Company will continue to apply this process until a sufficient amount of historical information regarding the volatility of its own stock price becomes available.

▪Risk-Free Interest Rate. The risk-free interest rate is based on the U.S. Treasury zero-coupon issues in effect at the time of grant for periods corresponding with the expected term of the options.

▪Expected Dividend Yield. The Company never paid dividends on its common stock and do not anticipate paying any dividends in the foreseeable future. Therefore, the Company used an expected dividend yield of zero.

Significant changes to the key assumptions underlying the factors used could result in different fair values of common stock at each valuation date.

Commitments and Contingencies

The Company recognizes a liability with regard to loss contingencies when it believes it is probable a liability has been incurred, and the amount can be reasonably estimated. If some amount within a range of loss appears at the time to be a better estimate than any other amount within the range, the Company accrues that amount. When no amount within the range is a better estimate than any other amount the Company accrues the minimum amount in the range.

In the event the Company becomes subject to claims or suits arising in the ordinary course of business, the Company would accrue a liability for such matters when it is probable that future expenditures will be made and such expenditures can be reasonably estimated.

The Company has not recorded any such liabilities at either December 31, 2021 or 2020.

Income Taxes

The Company accounts for income taxes under the asset and liability method, which requires the recognition of deferred tax assets and liabilities for the expected future tax consequences of events that have been included in the financial statements. Under this method, deferred tax assets and liabilities are determined on the basis of the differences between the financial statements and tax basis of assets and liabilities using enacted tax rates in effect for the year in which the differences are expected to reverse. The effect of a change in tax rates on deferred tax assets and liabilities is recognized in income in the period that includes the enactment date.

The Company recognizes deferred tax assets to the extent that the Company believes these assets are more likely than not to be realized. In making such a determination, management considers all available positive and negative evidence, including future reversals of existing taxable temporary differences, projected future taxable income, tax-planning strategies, and results of recent operations. If management determines that the Company would be able to realize its deferred tax assets in the future in excess of their recorded amount, management would make an adjustment to the deferred tax asset valuation allowance, which would reduce the provision for income taxes.

As of December 31, 2021 and 2020, the Company maintained valuation allowances against its deferred tax assets as the Company concluded it had not met the “more likely than not” to be realized threshold. Changes in the valuation allowance when they are recognized in the provision for income taxes may result in a change in the estimated annual effective tax rate.

The Company records uncertain tax positions on the basis of a two-step process whereby (1) management determines whether it is more likely than not that the tax positions will be sustained on the basis of the technical merits of the position and (2) for those tax positions that meet the more-likely-than-not recognition threshold, management recognizes the largest amount of tax benefit that is more than 50 percent likely to be realized upon ultimate settlement with the related tax authority. The Company recognizes interest and penalties related to unrecognized tax benefits within income tax expense. Any accrued interest and penalties are included within the related tax liability. As of December 31, 2021, the Company had no accrued interest or penalties.

Net Loss Per Share

Basic net loss per share is calculated by dividing the net loss attributable to common stockholders by the weighted-average number of shares of common stock outstanding for the period. Diluted net loss per share is computed by dividing the net loss by the weighted average number of shares of common stock and common stock equivalents outstanding for the period. Common stock equivalents are only included when their effect is dilutive. The Company’s potentially dilutive securities include outstanding stock options under the Company’s equity incentive plan and have been excluded from the computation of diluted net loss per share as they would be anti-dilutive to the net loss per share. For all periods presented, there is no difference in the number of shares used to calculate basic and diluted shares outstanding due to the Company’s net loss position.

The following tables summarize the computation of the basic and diluted net loss per share (in thousands, except share and per share data):

	Year Ended December 31,
	2021			2020
Numerator:
Net loss	$	(66,971	)	$	(18,854	)
Denominator:
Weighted-average common shares outstanding, basic and diluted		18,587,782			3,517,671
Less: Weighted-average unvested common stock		(621,888	)		(1,272,448	)
Weighted-average shares used to compute net loss per share, basic and    diluted		17,965,894			2,245,223
Net loss per share, basic and diluted	$	(3.73	)	$	(8.40	)

The following table sets forth the outstanding potentially dilutive securities that have been excluded in the calculation of diluted net loss per share because their inclusion would be anti-dilutive.

	Year Ended December 31,
	2021		2020
Series A convertible preferred stock		—		32,198,879
Common stock options		6,591,727		641,427
ESPP shares		16,606		—
Unvested common stock		253,824		957,711
Total		6,862,157		33,798,017

Segments

The Company has determined that it operates and manages one operating segment, which is the business of researching and developing vaccines against infectious diseases. The Company’s chief operating decision maker, its chief executive officer, reviews financial information on an aggregate basis for the purpose of allocating resources. All assets of the Company are located in the United States.

Recent Accounting Pronouncements

Recently Adopted Accounting Standards

In December 2019, the FASB issued ASU 2019-12, Income Taxes—Simplifying the Accounting for Income Taxes (“ASU 2019-12”). The new guidance simplifies the accounting for income taxes by removing several exceptions in the current standard and adding guidance to reduce complexity in certain areas, such as requiring that an entity reflect the effect of an enacted change in tax laws or rates in the annual effective tax rate computation in the interim period that includes the enactment date. The new standard is effective for fiscal years beginning after December 15, 2021, and interim periods within fiscal years beginning after December 15, 2022 for all non-public entities, with early adoption permitted, and is effective for fiscal years beginning after December 15, 2020, including interim periods within those annual periods for public entities. Early adoption is permitted. The Company adopted ASU 2019-12 on January 1, 2021 and the standard did not have a material impact on its financial statements and related disclosures.