| Summary of Significant Accounting Policies and Use of Estimates | SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES AND USE OF ESTIMATES (i) Basis of Presentation The Company’s Condensed Financial Statements have been prepared in conformity with generally accepted accounting principles ("GAAP") in the United States ("U.S.") for interim financial information pursuant to Form 10-Q and with the rules and regulations of the Securities and Exchange Commission ("SEC"). Accordingly, the accompanying Condensed Financial Statements do not include all of the information and footnotes required by GAAP for complete financial statements and should be read in conjunction with the audited financial statements and the related notes thereto in the Company’s Annual Report on Form 10-K for the year ended December 31, 2022, as filed with the SEC on March 17, 2023. The interim Condensed Balance Sheet as of March 31, 2023, the interim Condensed Statements of Operations and Comprehensive Loss, the interim Condensed Statements of Stockholders’ Equity, and the interim Condensed Statements of Cash Flows for the three months ended March 31, 2023 and 2022, are unaudited. These unaudited interim financial statements have been prepared on the same basis as the Company’s annual financial statements and, in the opinion of management, reflect all adjustments, which consist of only normal and recurring adjustments for the fair presentation of its financial information. The financial data and other information disclosed in these notes related to the three-month periods are also unaudited. The Condensed Balance Sheet as of December 31, 2022 has been derived from the audited financial statements at that date but does not include all information and footnotes required by GAAP for annual financial statements. The condensed interim operating results for three months ended March 31, 2023 are not necessarily indicative of results to be expected for the year ending December 31, 2023 or any other interim or annual period. The preparation of financial statements in conformity with GAAP and with the rules and regulations of the SEC requires management to make informed estimates and assumptions that affect the amounts reported in these financial statements and accompanying notes. These estimates and assumptions are based upon historical experience, knowledge of current events and various other factors believed to be reasonable under the circumstances, the results of which form the basis for making judgments about the carrying values of assets and liabilities and the recording of expenses that are not readily apparent from other sources and involve judgments with respect to numerous factors that are difficult to predict and may materially differ from the amounts ultimately realized and reported due to the inherent uncertainty of any estimate or assumption. Actual results could differ materially from those estimates. The Company’s financial statements as of and for the year ended December 31, 2022, reflect the Company’s estimates of the impact of the macroeconomic environment, including the impact of inflation, higher interest rates, and foreign exchange rate fluctuations. The duration and the scope of these conditions cannot be predicted; therefore, the extent to which these conditions will directly or indirectly impact the Company’s business, results of operations and financial condition, is uncertain. The Company is not aware of any specific event or circumstance that would require an update to its estimates, judgments and assumptions or a revision of the carrying value of the Company’s assets or liabilities as of the issuance date of the accompanying Condensed Financial Statements. Certain amounts in the prior years' financial statements have been reclassified to conform to the current year presentation. The Company reclassified license fees revenue and collaboration revenue which were historically separate financial statement line items on the Company's Statements of Operations and Comprehensive Loss and are now presented as a single revenue line — license fees and collaboration revenue. These reclassifications have no impact on total revenue or net loss. There have been no significant changes in the Company’s significant accounting policies during the three months ended March 31, 2023, as compared with those disclosed in its Annual Report on Form 10-K for the year ended December 31, 2022, filed with the SEC on March 17, 2023, except as discussed below. The accounting policies and estimates that most significantly impact the presented amounts within the accompanying Condensed Financial Statements are further described below. (ii) Cash and Cash Equivalents Cash and cash equivalents consist of bank deposits and highly liquid investments, including money market fund accounts, that are readily convertible into cash without penalty, with original maturities of three months or less from the purchase date. The carrying amounts reported in the accompanying Condensed Balance Sheets for cash and cash equivalents are valued at cost, which approximate their fair value. (iii) Marketable Securities and Long-Term Investments Marketable securities consist of short-term fixed income investments carried at estimated fair value as determined based upon quoted market prices or pricing models for similar securities (see Note 3 ). Management determines the appropriate classification of its investments in fixed income securities at the time of purchase. Available-for-sale securities are classified as current assets on the accompanying Condensed Balance Sheets due to their highly liquid nature and availability for use in current operations. Marketable securities are recorded at fair value with unrealized losses and gains reported as a component of accumulated other comprehensive loss within the accompanying Condensed Statements of Stockholders' Equity until realized. The Company periodically evaluates whether declines in fair values of its available-for-sale securities below their book value are other-than-temporary. This evaluation consists of several qualitative and quantitative factors regarding the severity and duration of the unrealized loss as well as the Company’s ability and intent to hold the available-for-sale security until a forecasted recovery occurs. The cost of debt securities is adjusted for amortization of premiums and accretion of discounts to maturity. Such amortization and accretion, as well as interest and dividends, are included in interest income. Realized losses and gains as well as credit losses, if any, on marketable securities identified on a specific identification basis and are included in other income (expense), net on the accompanying Condensed Statement of Operations and Comprehensive Loss. The Company evaluated the underlying credit quality and credit ratings of the issuers during the period. To date, the Company has not identified any other than temporary declines in fair value of its investments and no credit losses associated with credit risk have occurred or have been recorded. Interest earned on marketable securities is included in interest income within the accompanying Condensed Statements of Operations and Comprehensive Loss. Long-term investments consist of holdings of common stock in the publicly-traded parent company of LianBio Ophthalmology Limited ("LianBio"), reflecting the intent to hold these shares for at least one year from the balance sheet date. These equity securities are designated as available-for-sale with associated gains or losses reported in other income (expense), net within the Condensed Statements of Operations and Comprehensive Loss for each reported period. (iv) Fair Value Measurements Assets and liabilities recorded at fair value on a recurring basis in the balance sheets are categorized based upon the level of judgment associated with the inputs used to measure their fair values. Fair value is defined as the exchange price that would be received for an asset or an exit price that would be paid to transfer a liability in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. Valuation techniques used to measure fair value must maximize the use of observable inputs and minimize the use of unobservable inputs. The authoritative guidance on fair value measurements establishes a three-tier fair value hierarchy for disclosure of fair value measurements as follows: • Level 1: Quoted prices (unadjusted) in active markets for identical assets or liabilities that are publicly accessible at the measurement date. • Level 2: Observable prices that are based on inputs not quoted on active markets, but that are corroborated by market data. These inputs may include quoted prices for similar assets or liabilities or quoted market prices in markets that are not active to the general public. • Level 3: Unobservable inputs that are supported by little or no market activity and that are significant to the fair value of the assets or liabilities. The carrying amounts for financial instruments consisting of cash, cash equivalents, short-term marketable securities, long-term investments, accounts payable and accrued liabilities approximate fair value due to the short maturities for each. The Company's equity warrant holdings disclosed as other assets are carried at fair value based on unobservable market inputs (see Note 3 ). Assets and liabilities are classified based on the lowest level of input that is significant to the fair value measurements. The Company reviews the fair value hierarchy classification on a quarterly basis. Changes in the ability to observe valuation inputs may result in a reclassification of levels for certain assets or liabilities within the fair value hierarchy. The Company did not have any transfers of assets and liabilities between the levels of the fair value hierarchy during the years presented. (v) Property and Equipment, Net Property and equipment, net are stated at historical cost less accumulated depreciation. Depreciation is calculated using the straight-line method over the estimated useful lives of the assets that range from three improvements are amortized on a straight-line basis over the shorter of the remaining lease term or the estimated useful lives of related improvements. The Company evaluates the recoverability of its property and equipment, net whenever events or changes in circumstances of the business indicate that the asset’s carrying amount may not be recoverable. Recoverability of these assets is measured by a comparison of the carrying amounts to the sum of the future undiscounted cash flows the assets are expected to generate over the remaining useful lives of the assets. If a long-lived asset fails a recoverability test, the Company measures the amount by which the carrying value of the asset exceeds its fair value. There were no impairments recognized during the three months ended March 31, 2023 and 2022. (vi) Concentration of Credit Risk and Other Risks and Uncertainties Financial instruments that potentially subject the Company to significant concentrations of credit risk consist primarily of cash, cash equivalents and marketable securities. The Company maintains cash held in deposit at financial institutions in the U.S., including Silicon Valley Bank ("SVB"). As of March 31, 2023 and December 2022, the Company held cash and cash equivalents in its depository accounts of $8.1 million and $15.0 million, respectively. These deposits are insured by the Federal Deposit Insurance Corporation ("FDIC") in an amount up to $250,000 for any depositor. To the extent the Company holds cash deposits in amounts that exceed the FDIC insurance limitation, it may incur a loss in the event of a failure of any of the financial institutions where it maintains deposits. The Company's monitoring ongoing events involving limited liquidity, defaults, non-performance or other adverse developments that affect financial institutions, including SVB. On March 10, 2023, SVB was closed by the California Department of Financial Protection and Innovation, which appointed the FDIC as receiver, and all of SVB’s deposits and substantially all of SVB’s assets were transferred into a new entity, Silicon Valley Bridge Bank, N.A. (“SVBB”). On March 12, 2023, the Department of the Treasury, the Federal Reserve and the FDIC jointly released a statement that depositors at SVB would have access to their funds, even those in excess of the standard FDIC insurance limits, under a systemic risk exception. Such parties also announced, among other items, that SVBB had assumed the obligations and commitments of former SVB and commitments to advance under existing credit agreements with former SVB will be honored by SVBB pursuant to the terms of such credit agreements. On March 27, 2023, First Citizens Bank assumed all of SVBB’s obligations and commitments, and SVBB began operating as Silicon Valley Bank, a division of First Citizens Bank. Unless otherwise noted herein, all references to SVB or Silicon Valley Bank shall refer to Silicon Valley Bank, a division of First Citizens Bank. In light of the foregoing, the Company does not believe it has exposure to loss as a result of SVB’s receivership. Management believes the Company is not exposed to significant credit risk due to the financial position of the depository institution, but will continue to monitor regularly and adjust, if needed, to mitigate risk. The Company has established guidelines regarding diversification of its investments and their maturities, which are designed to maintain principal and maximize liquidity. To date, the Company has not experienced any losses associated with this credit risk and continues to assess that this exposure is not significant. (vii) Revenue Recognition for Out-License Arrangements Overview The Company currently has no product revenue. Reported revenue in the accompanying Condensed Statements of Operations and Comprehensive Loss is associated with one out-license agreement (the "China Out-License") that allows the third-party licensee to market the Company's TP-03 product candidate (representing functional intellectual property) in the People's Republic of China, Hong Kong, Macau, and Taiwan (the "China territory")— see Note 9 . The accounting and reporting of revenue for out-license arrangements requires significant judgment for: (a) identification of the number of performance obligations within the contract, (b) the contract’s transaction price for allocation (including variable consideration), (c) the stand-alone selling price for each identified performance obligation, and (d) the timing and amount of revenue recognition in each period. The China Out-License was analyzed under GAAP to determine whether the promised goods or services are distinct or must be accounted for as part of a combined performance obligation. In making these assessments, the Company considers factors such as the stage of development of the underlying intellectual property and the capabilities of the customer to develop the intellectual property on their own, and/or whether the required expertise is readily available. If the license is not distinct, the license is combined with other promised goods or services as a combined performance obligation for revenue recognition. The China Out-License arrangement included the following forms of consideration: (i) non-refundable upfront license payment, (ii) equity-based consideration, (iii) sales-based royalties, (iv) sales-based threshold milestones, (v) one-time payments for executing drug supply agreements, (vi) development milestone payments, and (vii) regulatory milestone payments. Revenue is recognized in proportion to the allocated transaction price when (or as) the respective performance obligation is satisfied. The Company evaluates the progress related to each milestone at each reporting period and, if necessary, adjusts the probability of achievement and related revenue recognition. The measure of progress, and thereby periods over which revenue is recognized, is subject to estimates by management and may change over the course of the agreement. Contractual Terms for Receipt of Payments A performance obligation is a promise in a contract to transfer a distinct good or service and is the unit of accounting. A contract’s transaction price is allocated among each distinct performance obligation based on relative standalone selling price and recognized when, or as, the applicable performance obligation is satisfied. The contractual terms that establish the Company’s right to collect specified amounts from its customers and that require contemporaneous evaluation and documentation under GAAP for the corresponding timing and amount of revenue recognition, are as follows: (1) Upfront License Fees: The Company determines whether non-refundable license fee consideration is recognized at the time of contract execution (i.e., when the license is transferred to the customer and the customer is able to use and benefit from the license) or over the actual (or implied) contractual period of the China Out-License. The Company also evaluates whether it has any other requirements to provide substantive services that are inseparable from the performance obligation of the license transfer to determine whether any combined performance obligation is satisfied over time or at a point in time. Upfront payments may require deferral of revenue recognition to a future period until the Company performs obligations under these arrangements. (2) Development Milestones: The Company utilizes the most likely amount method to estimate the amount of consideration to which it will be entitled for achievement of development milestones as these represent variable consideration. For those payments based on development milestones (e.g., patient dosing in a clinical study or the achievement of statistically significant clinical results), the Company assesses the probability that the milestone will be achieved, including its ability to control the timing or likelihood of achievement, and any associated revenue constraint. Given the high degree of uncertainty around the occurrence of these events, the Company determines the milestone and other contingent amounts to be constrained until the uncertainty associated with these payments is resolved. At each reporting period, the Company re-evaluates this associated revenue recognition constraint. Any resulting adjustments are recorded to revenue on a cumulative catch-up basis, and reflected in the financial statements in the period of adjustment. (3) Regulatory Milestones: The Company utilizes the most likely amount method to estimate the consideration to which it will be entitled and recognizes revenue in the period regulatory approval occurs (the performance obligation is satisfied) as these represent variable consideration. Amounts constrained as variable consideration are included in the transaction price to the extent that it is probable that a significant reversal in the amount of cumulative revenue recognized will not occur when the uncertainty associated with the variable consideration is subsequently resolved. The Company evaluates whether the milestones are considered probable of being reached and not otherwise constrained. Accordingly, due to the inherent uncertainty of achieving regulatory approval, associated milestones are deemed constrained for revenue recognition until achievement. (4) Royalties: Under the sales-or-usage-based royalty exception the Company recognizes revenue based on the contractual percentage of the licensee’s sale of products to its customers at the later of (i) the occurrence of the related product sales or (ii) the date upon which the performance obligation to which some or all of the royalty has been allocated has been satisfied or partially satisfied. To date, the Company has not recognized any royalty revenue from the China Out-License. (5) Sales Threshold Milestones: Similar to royalties, applying the sales-or-usage-based royalty exception, the Company recognizes revenue from sales threshold milestones at the later of (i) the period the licensee achieves the one-time annual product sales levels in their territories for which the Company is contractually entitled to a specified lump-sum receipt, or (ii) the date upon which the performance obligation to which some or all of the milestone has been allocated has been satisfied or partially satisfied. To date, the Company has not recognized any sales threshold milestone revenue from the China Out-License. The Company re-evaluates the measure of progress to each performance obligation in each reporting period as uncertain events are resolved and other changes in circumstances occur. (viii) Research and Development Costs Research and development costs are expensed as incurred or as certain upfront or milestone payments become contractually due to licensors upon the achievement of clinical or regulatory events. Research and development expenses include internal costs directly attributable to in-development programs, including costs of certain salaries and other employee-related costs (including stock-based compensation), and costs to conduct nonclinical studies, clinical trials and contract manufacturing activities. The Company accrues these costs based on factors such as estimates of the work completed and in accordance with agreements established with third-party service providers under the service agreements. As it relates to clinical trials, 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. Payments made prior to the receipt of goods or services to be used in research and development are capitalized until the goods or services are received. Such payments are evaluated for current or long-term classification based on when they will be realized. The Company's objective is to reflect the appropriate expense in its financial statements by matching those expenses with the period in which the services and efforts are expended. The Company accounts for these expenses according to the progress of the trial as measured by patient progression and the timing of various aspects of the trial taking into consideration discussions with applicable personnel and outside service providers. The clinical trial accrual is dependent in part upon the timely and accurate reporting of progress and efforts incurred from contract research organizations ("CROs"), contract manufacturers and other third-party vendors. Although estimates are expected to be materially consistent with actual amounts incurred, the Company's understanding of the status and timing of services performed relative to the actual status and timing of services performed can vary and may result in changes in estimates in any particular period. The Company makes significant judgments and estimates in determining the accrued liabilities balance at each reporting period. As actual costs become known, the Company adjusts its accrued liabilities. To date, there have been no material differences between estimates of such expenses and the amounts actually incurred. (ix) Stock-Based Compensation The Company recognizes stock-based compensation expense for equity awards granted to employees, consultants, and members of its Board of Directors. Stock option awards are at an exercise price of not less than 100% of the fair market value of common stock on the respective date of grant. The grant date is the date the terms of the award are formally approved by the Company’s Board of Directors or its designee. The Company uses the Black-Scholes option pricing model to estimate the fair value of stock option awards as of the date of grant. The fair value of restricted stock units is representative of the closing market price of the Company's stock on the date preceding the award grant date. Stock awards granted typically have one All stock-based compensation expense is reported in the accompanying Condensed Statements of Operations and Comprehensive Loss within research and development expense or general and administrative expense, based upon the assigned department of the award recipient. The measurement of the fair value of stock option awards and recognition of stock-based compensation expense requires assumptions to be estimated by management that involve inherent uncertainties and the application of management’s judgment, including: Fair Value of Common Stock — Subsequent to the IPO, the fair value of the Company’s common stock is based on the closing quoted market price of its common stock as reported by the Nasdaq Global Select Market on the date of the option grant. Expected Term — The Company’s expected term represents the period that the Company’s stock option awards are expected to be outstanding. Management estimates the expected term of awarded stock options utilizing the simplified method (based on the mid-point between the vesting date and the end of the contractual term) to determine the expected term since the Company does not yet have sufficient exercise history. Expected Volatility — Prior to 2023, the Company did not have sufficient trading history for its common stock to use its own historical volatility. Management estimated the expected volatility based on a designated peer-group of publicly-traded companies for a look-back period (from the date of grant) that corresponded with the expected term of the awarded stock option. Beginning in January 2023, the Company began using its own historical stock price for expected volatility. Risk-Free Interest Rate — The Company estimates the risk-free interest rate based upon the U.S. Department of Treasury yield curve in effect at award grant date for the time period that corresponds with the expected term of the awarded stock option. Dividend Yield — The Company’s expected dividend yield is zero because it has never paid cash dividends and does not expect to for the foreseeable future. (x) Net Loss per Share Basic net loss per share is calculated by dividing the net loss by the weighted-average number of shares of common stock outstanding for the period, without consideration for potential dilutive shares of common stock. Diluted net loss per share is computed by dividing the net loss by the weighted-average number of common stock equivalents outstanding for the period determined using the treasury-stock method and if-converted method as applicable. Due to a net loss for the three months ended March 31, 2023 and 2022, all otherwise potentially dilutive securities are antidilutive, and accordingly, the reported basic net loss per share equals the reported diluted net loss per share in each period presented. (xi) Comprehensive Loss Comprehensive loss represents (i) net loss for the periods presented, and (ii) unrealized gains or losses on the Company's reported available-for-sale debt securities. (xii) Recently Issued or Effective Accounting Standards Recently issued or effective accounting pronouncements that impact, or may have an impact, on the Company’s financial statements have been discussed within the footnote to which each relates. Other recent accounting pronouncements not disclosed in these Condensed Financial Statements have been determined by the Company’s management to have no impact, or an immaterial impact, on its current financial position, results of operations, or cash flows. |
