Summary of Significant Accounting Policies | 2. Summary of Significant Accounting Policies Basis of Presentation and Unaudited Condensed Interim Financial Information The accompanying unaudited interim financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America (“GAAP”) and applicable rules and regulations of the SEC for interim reporting. As permitted under those rules and regulations, certain footnotes or other financial information normally included in financial statements prepared in accordance with GAAP have been condensed or omitted. The condensed interim financial statements have been prepared on the same basis as the annual financial statements and, in the opinion of management, reflect all adjustments, which include only normal, recurring adjustments that are necessary to present fairly the Company’s results for the interim periods presented. The condensed balance sheet as of December 31, 2020, is derived from the Company’s audited financial statements. The results of operations for the three and nine months ended September 30, 2021, are not necessarily indicative of the results to be expected for the year ending December 31, 2021, or for any other future annual or interim period. The accompanying unaudited condensed interim financial statements should be read in conjunction with the audited financial statements and the related notes thereto for the year ended December 31, 2020, which are included in the Company’s prospectus related to the Company’s IPO, filed with the SEC on August 25, 2021, pursuant to Rule 424(b) under the Securities Act of 1933. Use of Estimates The preparation of unaudited condensed interim financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts reported in the unaudited condensed interim financial statements and accompanying notes. The Company bases its estimates on historical experience and market-specific or other relevant assumptions that it believes are reasonable under the circumstances. Assets and liabilities reported in the Company’s condensed balance sheets and expenses and income reported are affected by estimates and assumptions, which are used for, but are not limited to, determining the fair value of assets and liabilities, including the accrual of certain liabilities, the valuation of financial instruments, the fair value of the Company’s common stock, income tax uncertainties, and measurement of stock-based compensation expense. Actual results could differ from such estimates or assumptions. 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 and cash equivalents. The Company maintains bank deposits in federally insured financial institutions and these deposits may exceed federally insured limits. The Company is exposed to credit risk in the event of default by the financial institutions holding its cash and cash equivalents to the extent recorded in the condensed balance sheets. The Company has not experienced any losses on its deposits of cash and cash equivalents. The Company is subject to a number of risks similar to other early-stage biopharmaceutical companies, including, but not limited to, the need to obtain adequate additional funding, possible failure of current or future preclinical studies or clinical trials, its reliance on third parties to conduct its clinical trials, the need to obtain regulatory and marketing approvals for its product candidates, competitors developing new technological innovations, the need to successfully commercialize and gain market acceptance of the Company’s product candidates, protection of its proprietary technology, and the need to secure and maintain adequate manufacturing arrangements with third parties. The Company relied, and expects to rely, on a small number of third-party manufacturers to manufacture and supply its RenovoCath devices and its product candidates for clinical trials. These activities could be adversely affected by a significant interruption in supply of these items. If the Company does not successfully commercialize or partner any of its product candidates, it will be unable to generate product revenue or achieve profitability. Deferred Offering Costs The Company incurred offering costs consisting of legal, accounting and other fees and costs directly attributable to the Company’s IPO. For the three and nine months ended September 30, 2021, the Company charged $ 774,000 no Operating Segment The Company operates and manages its business as one reportable and operating segment, which is the development of a platform technology to deliver de-risked small molecules for localized treatment of solid cancer tumors. The Company’s chief executive officer, who is the chief operating decision maker, reviews financial information on an aggregate basis for allocating resources and evaluating financial performance. Cash and Cash Equivalents The Company considers all highly liquid investments purchased with original maturities of 90 days or less from the purchase date to be cash equivalents. Cash and cash equivalents are held in accounts at financial institutions. Cash equivalents consist of amounts held in a money market account. Such deposits have and will continue to exceed federally insured limits in the foreseeable future. Leasehold Improvements, Net Leasehold improvements are presented at cost, net of accumulated amortization. Amortization expense is recorded using the straight-line method over the shorter of the remaining lease term or the estimated useful life. Convertible Instruments and Embedded Derivatives The Company accounts for certain redemption features that are associated with convertible notes as liabilities at fair value and adjusts the instruments to their fair value at the end of each reporting period. For derivative financial instruments that are accounted for as liabilities, the derivative instrument is initially recorded at its fair value and is then re-valued at each reporting date, with changes in the fair value reported in other income (expense), net in the condensed statements of operations. Derivative instrument liabilities are classified in the condensed balance sheets as current or non-current based on whether or not net-cash settlement of the derivative instrument could be required within 12 months of the balance sheet date. As of December 31, 2020, the Company’s only derivative financial instrument was related to the 2020 Convertible Notes, which contained certain redemptive features. The Company completed its IPO on August 30, 2021, which triggered the automatic conversion of all outstanding Convertible Notes, plus accrued interest, into units, consisting of (a) one share of common stock and (b) one five-year warrant to purchase one share of common stock at an exercise price equal to $10.80 per share. Upon the conversion of the Convertible Notes, the outstanding Convertible Notes, plus accrued interest thereon totaling $ 5.3 million, net of unamortized debt discounts, were derecognized into stockholders’ equity (Note 5). Clinical Trial Expenses The Company makes payments in connection with its ongoing Phase 3 clinical trial under contracts with clinical trial sites and contract research organizations that support conducting and managing clinical trials. The financial terms of these agreements are subject to negotiation and vary from contract to contract and may result in uneven payment flows. Generally, these agreements set forth the scope of work to be performed at a fixed fee, unit price or on a time and materials basis. A portion of the obligation to make payments under these contracts depends on factors such as the successful enrollment or treatment of patients or the completion of other clinical trial milestones. Expenses related to clinical trials are accrued based on estimates and/or representations from service providers regarding work performed, including actual level of patient enrollment, completion of patient studies and progress of the clinical trials. Other incidental costs related to patient enrollment or treatment are accrued when reasonably certain. If amounts and obligations to pay under clinical trial agreements are modified (for instance, as a result of changes in the clinical trial protocol or scope of work to be performed), the accruals are adjusted accordingly. Revisions to contractual payment obligations are charged to expense in the period in which the facts that give rise to the revision become reasonably certain. In addition, the clinical trial sites involved in our Phase 3 clinical trial of RenovoGem are charged for the RenovoCath delivery devices used in the trial. The payments received from the clinical trial sites for the devices are adequate to cover the direct costs of manufacturing and offset research and development expenses. Research and Development Expenses Research and development expenses are charged to expense as incurred. Research and development expenses includes personnel costs including salaries, benefits and stock-based compensation for employees related to research and development activities. In addition, expenses for consultants that support clinical trial studies, materials costs, external clinical drug product manufacturing costs, outside services costs, regulatory activities including filing fees, fees for maintaining licenses and other amounts due to third-party agreements, laboratory materials, clinical trial, as noted above, and supplies to support our research activities, as well as allocated facility related costs. Fair Value Measurement Fair value is defined as the exchange price that would be received for an asset or paid to transfer a liability, or an exit price, in the principal or most advantageous market for that asset or liability in an orderly transaction between market participants on the measurement date. Fair value measurement establishes a fair value hierarchy that requires an entity to maximize the use of observable inputs, where available, and minimize the use of unobservable inputs when measuring fair value. The Company determined the fair value of financial assets and liabilities using the fair value hierarchy that describes three levels of inputs that may be used to measure fair value, as follows: Level 1—Quoted prices in active markets for identical assets and liabilities; Level 2—Inputs other than Level 1 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; and 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. As of September 30, 2021, fair value measurements consisted solely of cash equivalents which comprise money market securities. The carrying amounts of these instruments approximate their fair value. The carrying value of all remaining current assets and current liabilities approximate their fair value. Stock-Based Compensation Expense The Company maintains an equity incentive plan as a long-term incentive for selected employees, consultants, and directors. The plan allows for the issuance of incentive stock options, non-statutory stock options, stock appreciation rights, restricted stock grants, and restricted stock units. The Company accounts for stock-based compensation expense by measuring and recognizing compensation expense for all share-based payments made to employees and non-employees based on estimated grant-date fair values. The Company uses the straight-line method to allocate compensation cost to reporting periods over each recipient’s requisite service period, which is generally the vesting period over four years. The Company estimates the fair value of stock options granted to employees and non-employees using the Black-Scholes option pricing model. The Black-Scholes option pricing model requires the input of subjective assumptions, including expected volatility, expected dividend yield, expected term and the risk-free rate of return. Prior to the Company’s IPO, given the absence of a public trading market, the Company’s Board of Directors considered numerous objective and subjective factors to determine the fair value of the common stock at each grant date. These factors included, but were not limited to: (i) contemporaneous third-party valuations of common stock; (ii) the prices for preferred stock sold to outside investors; (iii) the rights and preferences of preferred stock relative to common stock; (iv) the lack of marketability of the Company’s common stock; (v) developments in the business; and (vi) the likelihood of achieving a liquidity event, such as an IPO or sale of the business, given prevailing market conditions. The methodology to determine the fair value of our common stock included estimating the fair value of the enterprise using the “backsolve” method, which is a market approach that assigns an implied enterprise value by accounting for all share class rights and preferences based on the latest round of financing. The total equity value implied was then applied in the context of an option pricing model to determine the value of each class of our shares. Future awards will be based on the closing price of the Company’s common stock as reported on the date of grant to determine the fair value of the award. Emerging Growth Company and Smaller Reporting Company Status The Company is an emerging growth company (“EGC”) as defined in the Jumpstart Our Business Startups Act of 2012 (“JOBS Act”) and may take advantage of reduced reporting requirements that are otherwise applicable to public companies. Section 107 of the JOBS Act exempts emerging growth companies from being required to comply with new or revised financial accounting standards until private companies are required to comply with those standards. The Company has elected to use the extended transition period for complying with new or revised accounting standards. From time to time, new accounting pronouncements are issued by the Financial Accounting Standards Board (“FASB”) or other standard setting bodies and adopted by the Company as of the specified effective date. Unless otherwise discussed, the impact of recently issued standards that are not yet effective will not have a material impact on the Company’s financial position or results of operations upon adoption. Recent Accounting Pronouncements Recently Adopted Accounting Pronouncements In June 2018, the FASB issued Accounting Standards Updates (“ASU”) No. 2018-07, Improvements to Nonemployee Share-Based Payment Accounting In August 2018, the FASB issued ASU 2018-13, Fair Value Measurement (Topic 820), Disclosure Framework — Changes to the Disclosure Requirements for Fair Value Measurement -In November 2016, the FASB ASU 2016-18, Statement of Cash Flows (Topic 230): Restricted Cash Recent Accounting Pronouncements Not Yet Adopted In February 2016, the FASB issued ASU No. 2016-02, Leases (Topic 842) Leases (Topic 842) Leases (Topic 842) In June 2016, the FASB issued ASU No. 2016-13, Financial Instruments – Credit Losses Codification Improvements to Topic 326, Financing Instruments – Credit Losses , In December 2019, the FASB issued ASU No. 2019-12, Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes In August 2020, the FASB issued ASU No. 2020-06, Debt – Debt with Conversion and Other Options (Subtopic 470-20) and Derivatives and Hedging – Contracts in Entity’s Own Equity (Subtopic 815-40) Accounting for Convertible Instruments and Contracts in an Entity |