Use of Estimates

The Company’s financial statements are prepared in accordance with GAAP. The preparation of the Company’s financial statements requires the Company to make estimates and assumptions that impact the reported amounts of assets, liabilities and expenses and the disclosure of contingent assets and liabilities in the financial statements and accompanying notes. Such estimates include the accrual of R&D expenses and stock-based compensation. Management evaluates its estimates on an ongoing basis.

Estimates are based on the Company’s historical experience, knowledge of current events and actions it may undertake in the future, and actual results may materially differ from these estimates and assumptions.

Concentration of Credit Risk

Financial instruments which potentially subject the Company to significant concentration of credit risk consist of cash, cash equivalents and short-term investments. The Company maintains deposits in federally insured financial institutions in excess of federally insured limits and invests in short-term investments with the primary objectives of seeking to preserve principal, achieve liquidity requirements and safeguard funds. Management believes that the Company is not exposed to significant credit risk due to the financial position of the depository institutions in which those deposits are held and the nature, including the credit-ratings, of its short-term investments, but we have not eliminated all credit risk.

Cash and Cash Equivalents

The Company considers all highly liquid investments with original maturities of three months or less when purchased to be cash equivalents. Cash and cash equivalents include cash in readily available checking accounts, money market funds, corporate debt securities, and obligations of U.S. government-sponsored enterprises. The carrying amounts reported in the unaudited condensed balance sheets for cash and cash equivalents are valued at cost, which approximates fair value.

Short-Term Investments

Short-term investments primarily consist of commercial paper, corporate debt securities, and government and agency bonds. The Company has classified these investments as available-for-sale securities, as the sale of such investments may be required prior to maturity to implement management strategies, and therefore has classified all investments with maturity dates beyond three months at the date of purchase as current assets in the accompanying unaudited balance sheets. Any premium or discount arising at purchase is amortized and/or accreted to interest income as an adjustment to yield using the straight-line method over the life of the instrument. Investments are reported at their estimated fair value. Unrealized gains and losses are included in accumulated other comprehensive loss as a component of stockholders' equity until realized.

R&D Expenses

R&D expenses are expensed in the periods in which they are incurred. External expenses consist primarily of payments to contract research organizations, outside consultants and other third parties in connection with the Company’s research, preclinical and clinical activities, process development, manufacturing activities, regulatory and other services. Certain R&D external expenses are recognized based on an evaluation of the progress to completion of specific tasks using information provided to the Company by its service providers or the estimate of the level of service that has been performed at each reporting date. R&D expenses amounted to $12.5 million, $21.1 million, $8.9 million and $16.0 million for the three and six months ended June 30, 2023 and 2022, respectively.

Stock-Based Compensation

Stock-based awards are measured at fair value and compensation expense is recognized over the requisite service period. Forfeitures are accounted for in the period they occur. The Company determines the fair value of each stock-based award on the date of grant using the Black-Scholes option pricing model which requires the input of subjective assumptions, including price volatility of the underlying stock, risk-free interest rate, dividend yield, and expected term of the option.

Leases

The Company determines if an arrangement is a lease or contains lease components at inception. Lease terms are determined at the commencement date by considering whether renewal options and termination options, if any, are reasonably assured of exercise. For long-term operating leases, the Company recognizes a lease liability and a right-of-use (ROU) asset on its balance sheets and recognizes lease expense on a straight-line basis over the lease term. The lease liability is determined as the present value of future lease payments using the discount rate implicit in the lease or, if the implicit rate is not readily determinable, an estimate of the

Company’s incremental borrowing rate. The ROU asset is based on the lease liability, adjusted for any prepaid or deferred rent. The Company only has operating leases and does not have any financing leases.

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 during the period. Diluted net loss per share is computed by dividing the net loss attributable to common stockholders by the weighted-average number of shares of common stock and potentially dilutive securities outstanding for the period. Since the Company had a net loss in each of the periods presented, basic and diluted net loss per share of common stock are the same.

The table below provides potentially dilutive securities not included in the calculation of the diluted net loss per share as it would be anti-dilutive:


	Six Months Ended June 30,
	2023		2022
Options to purchase common stock		4,007,386		2,496,166
Restricted stock awards, issued but unvested		—		58,081
Total		4,007,386		2,554,247

Recent Accounting Pronouncements

In June 2016, the FASB issued ASU No. 2016-13, Financial Instruments - Credit Losses (ASU 2016-13), to improve financial reporting by requiring timely recording of credit losses on loans and other financial instruments held by financial institutions and other organizations. ASU 2016-13 requires the measurement of all expected credit losses for financial assets held at the reporting date based on historical experience, current conditions and reasonable and supportable forecasts. This guidance became effective for the Company on January 1, 2023. The adoption of this standard did not have a material impact on the Company’s financial statements.

Risks and Uncertainties

In December 2019, COVID-19, a novel strain of coronavirus, was first identified in Wuhan, China. In March 2020, the World Health Organization categorized COVID-19 as a pandemic, and the virus has spread to over 100 countries, including the United States. The impact of this pandemic has been and may continue to be extensive in many aspects of society, which has resulted in and may continue to result in significant disruptions to the global economy, as well as businesses and capital markets around the world.

Potential impacts to the Company’s business include, but are not limited to, temporary closures of facilities of its vendors, disruptions or restrictions on its employees’ ability to travel, disruptions to or delays in ongoing laboratory experiments, preclinical studies, clinical trials, third-party manufacturing supply and other operations, the potential diversion of healthcare resources away from the conduct of clinical trials to focus on pandemic concerns, interruptions or delays in the operations of the U.S. Food and Drug Administration or other regulatory authorities, and the Company’s ability to raise capital and conduct business development activities.

In February 2022, Russia commenced a military invasion of Ukraine causing ongoing geopolitical turmoil, including continuing military action in the region and sanctions imposed on Russia.

These and other events have caused and may continue to cause significant disruption, instability and volatility in the global economy and financial markets, resulting in inflation, rising interest rates, tightening of credit markets and bank failures, the actual or anticipated occurrence of which may have an adverse impact on the Company’s business or ability to access capital markets in the future.