RAIN Rain Oncology Inc

Notes to Condensed Financial Statements (unaudited)

Note 1 – Organization and Nature of Operations

Description of Business

Rain Therapeutics Inc. (“Rain” or the “Company”) was incorporated in the state of Delaware in April 2017. Rain is a late-stage precision oncology company developing therapies that target oncogenic drivers for which the Company is able to genetically select patients the Company believes will be most likely to benefit. This approach includes using a tumor-agnostic strategy to select patients based on their tumors’ underlying genetics rather than histology. Rain’s lead product candidate, milademetan, is a small molecule, oral inhibitor of mouse double minute 2, which may be oncogenic in numerous cancers. In addition to milademetan, the Company is also developing a preclinical program that is focused on inducing synthetic lethality in cancer cells by inhibiting RAD52. The Company operates in one business segment and its principal operations are in the United States, with its headquarters in Newark, California.

Reverse Stock Split

On April 15, 2021 and April 16, 2021, the Company’s board of directors (the “Board of Directors”) and stockholders, respectively, approved an amended and restated certificate of incorporation of the Company to effect a 1-for-1.0799 reverse stock split of the Company’s common stock. The reverse stock split was effected on April 16, 2021. The Company’s outstanding stock options were also adjusted to reflect the 1-for-1.0799 reverse stock split of the Company’s common stock. Accordingly, all common stock and stock options and related per share amounts in these financial statements have been retroactively adjusted for all periods presented to give effect to the reverse stock split. Outstanding stock options were proportionately reduced and the respective exercise prices, if applicable, were proportionately increased. The reverse stock split resulted in an adjustment to the Series A and Series B convertible preferred stock conversion prices to reflect a proportional decrease in the number of shares of common stock to be issued upon conversion.

Initial Public Offering

On April 27, 2021, the Company completed its initial public offering (“IPO”) in which the Company issued and sold 7,352,941 shares of common stock at a public offering price of $17.00 per share. On May 11, 2021, the Company issued an additional 492,070 shares of common stock in connection with the exercise of the underwriters’ option to purchase additional shares at the public offering price. The Company’s net proceeds from the sale of shares in the IPO, including the sale of shares pursuant to the exercise of the underwriters’ option to purchase additional shares, was $121.5 million, net of underwriting discounts and commissions, and other offering fees.

Immediately prior to the closing of the IPO, 8,344,905 shares of the Company’s convertible preferred stock were exchanged for 7,727,470 shares of non-voting common stock. Upon the closing of the IPO, 7,928,501 shares of the Company’s convertible preferred stock were automatically converted into 7,341,860 shares of common stock. Following the IPO, there were no shares of convertible preferred stock outstanding.

Basis of Presentation

The accompanying interim unaudited condensed financial statements have been prepared in accordance with accounting principles generally accepted in the United States (“GAAP”) related to a quarterly report on Form 10-Q. 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”). The year-end balance sheet data was derived from the Company’s audited financial statements but does not include all disclosures required by GAAP. These condensed financial statements should be read in conjunction with the Company’s audited financial statements for the year ended December 31, 2021 included in the Company’s Annual Report on Form 10-K, filed pursuant to Section 13(a) or 15(d) of the Securities Exchange Act of 1934, as amended (the Exchange Act). The unaudited financial information for the interim periods presented herein reflects all adjustments which, in the opinion of management, are necessary for a fair presentation of the financial condition and results of operation for the periods presented, with such adjustments consisting only of normal recurring adjustments.

Liquidity and Capital Resources

The Company has devoted substantially all of its efforts to drug discovery and development, raising capital and building operations. The Company has a limited operating history and has not generated any revenue since its inception,

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and the sales and income potential of the Company’s business is unproven. The Company has incurred net losses and negative cash flows from operating activities since its inception and expects to continue to incur net losses into the foreseeable future as it continues the development of its product candidates. From inception through March 31, 2022, the Company has funded its operations through net proceeds from its IPO in April 2021, and the issuance of convertible promissory notes and convertible preferred stock.

The accompanying condensed financial statements have been prepared assuming the Company will continue as a going concern. Management believes that the Company’s current cash, cash equivalents and short-term investments will provide sufficient funds to enable the Company to meet its obligations for at least twelve months from the filing date of this report.

Note 2 – Summary of Significant Accounting Policies

Use of Estimates

The preparation of the Company’s condensed financial statements in conformity with GAAP requires management to make estimates and assumptions that impact the reported amounts of assets, liabilities and expenses and the disclosure of contingent liabilities in the Company’s condensed financial statements and accompanying notes. The most significant estimate in the Company’s condensed financial statements relates to the clinical trial expense accruals. Management evaluates its estimates on an ongoing basis. Although these estimates are based on the Company’s historical experience, knowledge of current events and actions it may undertake in the future, actual results may ultimately materially differ from these estimates and assumptions.

Cash and Cash Equivalents

The Company considers all highly liquid investments with an original maturity of three months or less at the date of purchase to be cash equivalents. Cash equivalents include commercial paper, readily available money market and checking accounts.

Available-for-Sale Investments

The Company holds investment grade securities consisting of money market funds, commercial paper, corporate debt securities, U.S. government securities and U.S. agency bonds, classified as available-for-sale (“AFS”) securities at the time of purchase, since it is the Company’s intent that these investments be available for current operations. The Company has classified all of its AFS securities as current assets on the condensed balance sheets even though the stated maturity date may be one year or more beyond the current condensed balance sheet date, which reflects management’s intention to use the proceeds from sales of these securities to fund its operations, as necessary.

The Company carries these securities at fair value and reports unrealized gains and losses, if any, as a separate component of accumulated other comprehensive loss. The cost of debt securities is adjusted for amortization of purchase premiums and accretion of discounts to maturity. Such amortization and accretion are included in interest income in the condensed statements of operations and comprehensive loss. Realized gains and losses on sales of securities are determined using the specific identification method and recorded in other income (expense), net in the condensed statement of operations and comprehensive loss.

Investments are considered to be impaired when a decline in fair value is judged to be other-than-temporary. The Company consults with its investment managers and considers available quantitative and qualitative evidence in evaluating potential impairment of its investments on a quarterly basis. If the cost of an individual investment exceeds its fair value, the Company evaluates among other factors, general market conditions, the duration and extent to which the fair value is less than cost, and the Company’s intent and ability to hold the investment. Once an impairment is determined to be other-than-temporary, an impairment charge is recorded and a new cost basis in the investment is established. Declines in the value of AFS securities determined to be other than temporary are included in other income (expense), net.

Deferred Offering Costs

The Company capitalized deferred offering costs consisting of all direct and incremental legal, professional, accounting and other third-party fees incurred in connection with the Company’s IPO. Upon the completion of the IPO in April 2021, the total deferred offering costs of $2.5 million were reclassified to additional paid-in capital on the condensed balance sheets.

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Research and Development Costs

Research and development costs primarily consist of costs associated with the Company’s research and development activities, including its drug discovery efforts, and the preclinical and clinical development of its product candidates. Research and development costs are expensed as incurred.

Preclinical Studies and Clinical Trial Accruals

The Company is required to estimate its expenses resulting from its obligations under contracts with vendors, consultants, clinical research organizations and clinical site agreements in connection with conducting preclinical activities and 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. The Company reflects preclinical study and clinical trial expenses in its condensed financial statements by matching those expenses with the period 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 preclinical study, clinical trial or related activities. The Company determines accrual and prepaid estimates through review of the underlying contracts along with preparation of financial models taking into account correspondence with clinical and other key personnel and third-party service providers as to the progress of preclinical studies, clinical trials or other services being conducted. During the course of a preclinical study or clinical trial, the Company adjusts its expense recognition if actual results differ from its estimates. To date, the Company has not experienced any material differences between accrued costs and actual costs incurred.

Stock-Based Compensation

Stock-based compensation expense represents the grant date fair value of equity awards recognized over the requisite service period of the awards (generally the vesting period) on a straight-line basis. The Company recognizes forfeitures as they occur. The Company estimates the fair value of stock option grants using the Black-Scholes option pricing model. Prior to the IPO, the exercise price for all stock options granted was at the estimated fair value of the underlying common stock as determined on the date of grant by the Company’s Board of Directors.

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 condensed 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.

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.

Effective January 1, 2022, we adopted ASU 2019-12 - Simplifying the Accounting for Income Taxes. The adoption of this standard did not impact the Company’s condensed financial statements or related disclosures.

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 includes unrealized gains / losses from short-term investments.

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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, without consideration of potential dilutive securities. Diluted net loss per share is computed by dividing the net loss attributable to common stockholders by the sum of the weighted-average number of shares of common stock plus the potential dilutive effects of potential dilutive securities outstanding during the period. Potential dilutive securities are excluded from diluted earnings or loss per share if the effect of such inclusion is antidilutive. The Company’s potentially dilutive securities, which include convertible preferred stock, shares from the 2021 Employee Stock Purchase Plan (the “ESPP”), and outstanding stock options under the Company’s equity incentive plan, 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 the 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.

Recent Developments Regarding the COVID-19 Pandemic

Efforts to control the outbreak of COVID-19 have resulted in challenges to businesses and facilities in various industries around the world, including disruptions to the global economy and supply chains. To date, COVID-19 has not had a material impact on the Company’s expenditures.

The Company is unable to predict the ultimate effects of COVID-19 on the U.S. or global economy or its operations. The Company continues to monitor developments affecting its workforce, suppliers, and operations. The extent of the impact of COVID-19 will depend on its duration, actions by government authorities, and impacts on the Company’s employees, or vendors. These developments are continuously evolving, and the Company cannot predict whether COVID-19 will have a material impact on its financial condition, results of operations or cash flows.

Recent Accounting Pronouncements

Financial Instruments. In June 2016, the FASB issued ASU 2016-13, Financial Instruments—Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments. The objective of the standard is to provide information about expected credit losses on financial instruments at each reporting date and to change how other-than temporary impairments on investment securities are recorded. The guidance is effective for the Company beginning on January 1, 2023, with early adoption permitted. The Company does not anticipate that the adoption of ASU 2016-13 will have a significant impact on its condensed financial statements or the related disclosures.

There were no other significant updates to the recently issued accounting standards other than as disclosed herein for the three months ended March 31, 2022. Although there are several other new accounting pronouncements issued or proposed by the FASB, based on the Company’s preliminary assessment, the Company does not believe any of those accounting pronouncements have had or will have a material impact on its financial position or operating results.

Note 3 – Fair Value Measurements

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 non-recurring 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. As a basis for considering such assumptions, the accounting guidance establishes a three-tier fair value hierarchy, which prioritizes the inputs used in measuring fair value as follows:

Level 1: Unadjusted quoted prices in active markets that are accessible at the measurement date for identical, unrestricted assets or liabilities.

Level 2: Quoted prices for similar assets and liabilities in active markets, quoted prices in markets that are not active, or inputs which are observable, either directly or indirectly, for substantially the full term of the asset or liability.

Level 3: Prices or valuation techniques that require inputs that are both significant to the fair value measurement and unobservable (i.e., supported by little or no market activity).

The carrying amounts of cash, prepaid expenses and other current assets, deferred offering costs, accounts payable, accrued research and development and other current liabilities are reasonable estimates of their fair value due to the short-term nature of these accounts.

The Company’s money market funds under cash and cash equivalents are classified using Level 1 inputs within the fair value hierarchy because they are valued using quoted market prices, broker or dealer quotations, or alternative

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pricing sources with reasonable levels of price transparency. There were no transfers between levels of the fair value hierarchy during the three months ended March 31, 2022.

The following table summarizes financial assets that the Company measured at fair value on a recurring basis, classified in accordance with the fair value hierarchy (in thousands):

Note 4 – Investments

Financial assets measured at fair value on a recurring basis consist of the Company’s cash equivalents and AFS securities. The Company obtains pricing information from its investment manager and generally determines the fair value of investment securities using standard observable inputs, including reported trades, broker/dealer quotes, and bids and/or offers.

Investments are classified as Level 1 within the fair value hierarchy if their quoted prices are available in active markets for identical securities. Investments in money market funds and U.S. government securities were classified as Level 1 instruments.

Investments in commercial paper, corporate debt securities and U.S. agency bonds are valued using Level 2 inputs. The Company classifies investments within Level 2 if the investments are valued using model driven valuations using observable inputs such as quoted market prices, benchmark yields, reported trades, broker/dealer quotes or alternative pricing sources with reasonable levels of price transparency. Investments are held by custodians who obtain investment prices from a third-party pricing provider that incorporates standard inputs in various asset price models.

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The following table summarizes, by major types of cash equivalents, and investments that are measured at fair value on a recurring basis (in thousands):

The contractual maturities of the Company’s AFS securities were as follows (in thousands):

The available-for-sale investments are classified as current assets, even though the stated maturity date may be one year or more beyond the current condensed balance sheet date, which reflects management’s intention to use the proceeds from sales of these securities to fund the Company’s operations, as necessary. There were no realized gains or losses due to investment sales for the three months ended March 31, 2022 and 2021. As of March 31, 2022, $111.7 million of the Company’s marketable securities were in gross unrealized loss positions, of which none had been in such position for greater than 12 months and $62.9 million will mature within three months of March 31, 2022.

At each reporting date, the Company performs an evaluation of its marketable securities to determine if any unrealized losses are other-than-temporary. Factors considered in determining whether a loss is other-than-temporary include (i) the financial strength of the issuing institution, (ii) the length of time and extent for which fair value has been less than the cost basis and (iii) the Company’s intent and ability to hold its investments in unrealized loss positions until their amortized cost basis has been recovered. Based on the Company’s evaluation, it determined that its unrealized losses were not other-than-temporary at March 31, 2022 and December 31, 2021. The Company does not intend to sell the investments before maturity and it is unlikely that the Company will be required to sell the investments before recovery of their amortized cost bases.

Note 5 - Condensed Balance Sheet Details

Prepaid and Other Current Assets

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Prepaid and other current assets consist of the following (in thousands):

Property and equipment, net, consist of the following (in thousands):

Depreciation expense for the three months ended March 31, 2022 and 2021 were $22,000 and $15,000, respectively.

Note 6 – Convertible Preferred Stock and Stockholders’ Equity

In connection with the reverse stock split on April 16, 2021, the Company filed a certificate of amendment to its certificate of incorporation, which authorized 260,000,000 shares of capital stock, consisting of 250,000,000 shares of common stock, par value $0.001 per share, and 10,000,000 shares of undesignated preferred stock, par value $0.001 per share that may be issued from time to time by the Company’s Board of Directors in one or more series. Of the 250,000,000 shares of common stock, 200,000,000 shares were designated as “Common Stock” and 50,000,000 shares were designated as “Non-Voting Common Stock”.

Rights, preferences, powers, privileges and restrictions, qualifications and limitations for holders of the Company’s Common Stock and Non-Voting Common Stock are:

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Convertible Preferred Stock

Series A Convertible Preferred Stock. In April 2018, the Company entered into a Series A convertible preferred stock purchase agreement, pursuant to which the Company issued 2,098,269 shares of Series A convertible preferred stock for an aggregate purchase price of $11.0 million, net of issuance costs. In December 2018, the Company issued an additional 1,390,788 shares of Series A convertible preferred stock for an aggregate purchase price of $7.3 million, net of issuance costs.

Series B Convertible Preferred Stock. In September 2020, the Company entered into a Series B convertible preferred stock purchase agreement, pursuant to which the Company issued 10,636,510 shares of Series B convertible preferred stock for an aggregate purchase price of $63.2 million, net of issuance costs.

Rights, preferences, powers, privileges and restrictions, qualifications and limitations for holders of the Company’s Series A convertible preferred stock and Series B convertible preferred stock are:

Prior to the IPO, the Company’s Series A and Series B convertible preferred stock were classified as temporary equity on the accompanying condensed balance sheet instead of in stockholders’ equity (deficit), as events triggering redemption that were not solely within the Company’s control because the preferred stockholders had the ability to effect a liquidation event. The Company determined not to adjust the carrying values of the Series A and Series B convertible preferred stock to the liquidation preferences of such shares because of the uncertainty of whether or when such liquidation events would occur.

On April 27, 2021, immediately prior to the closing of the IPO, 8,344,905 shares of the Company’s convertible preferred stock were exchanged for 7,727,470 shares of Non-Voting Common Stock and 7,928,501 shares of the Company’s convertible preferred stock converted into 7,341,860 shares of Common Stock. There were no outstanding shares of the Company’s convertible preferred stock as of March 31, 2022.

Equity Incentive Plan

In August 2020, the Company’s Board of Directors amended the Amended and Restated 2018 Stock Option—Stock Issuance Plan (the “2018 Plan”) to increase the maximum number of shares of common stock that may be issued over the term of the plan. The 2018 Plan provided for the grant of stock options, non-statutory stock options, incentive stock options and stock issuances to employees, nonemployees and consultants of the Company.

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In April 2021, the Company’s 2021 Equity Incentive Plan (the “2021 Plan”) was approved by the Company’s Board of Directors and became effective on April 15, 2021. Upon the effectiveness of the 2021 Plan, no further grants may be made under the Company’s 2018 Plan.

The 2021 Plan allows the Company to grant equity-based awards to its officers, employees, directors and other key persons (including consultants). The Company initially reserved up to 3,246,120 shares of common stock for issuance under the 2021 Plan, plus (i) 1,722 shares that remained available for the issuance of awards under the 2018 Plan at the time the 2021 Plan became effective, and (ii) any shares subject to outstanding options or other share awards that were granted under the 2018 Plan that terminate or expire prior to exercise or settlement; are forfeited because of the failure to vest; or are reacquired or withheld (or not issued) to satisfy a tax withholding obligation or the purchase or exercise price. The 2021 Plan provides that the number of shares reserved and available for issuance under the plan will automatically increase each January 1, beginning on January 1, 2022 and each January 1 thereafter through January 31, 2032, by 4.0% of the outstanding number of shares of common stock on the immediately preceding December 31, or such lesser number of shares as determined by the Company’s Board of Directors. As a result, the number of shares of common stock reserved for issuance under the 2021 Plan increased by 1,059,032 shares on January 1, 2022.

A summary of the Company’s stock option activities during the three months ended March 31, 2022 is as follows:

The weighted-average grant date fair values of option grants during the three months ended March 31, 2022 and 2021 were $8.71 and $4.09 per share, respectively. The weighted-average grant date fair values of options forfeited during the three months ended March 31, 2022 and 2021 were $12.69 and $3.07 per share, respectively.

Employee Stock Purchase Plan

The ESPP was approved by the Board of Directors and became effective on April 15, 2021. The ESPP initially reserved and authorized the issuance of up to 259,689 shares of common stock to participating employees. Under the ESPP, eligible employees can contribute up to 15% of their eligible compensation, as defined in the ESPP, towards the purchase of the Company’s common stock at a price of 85% of the lower of the fair market value of the Company’s common stock on the first trading day of the offering period or on the last trading day of the offering period. The ESPP provides for twenty-four-month offering periods with four six-month purchase periods in each offering period. The ESPP provides that the number of shares reserved and available for issuance will automatically increase each January 1, beginning on January 1, 2022 and each January 1 thereafter through January 31, 2032, by 1.0% of the total number of shares of common stock outstanding on December 31 of the preceding calendar year. As a result, the number of shares of common stock reserved for issuance under the ESPP increased by 264,758 shares on January 1, 2022. Under the ESPP, the Company issued 26,804 shares of common stock for aggregate cash proceeds of $0.3 million during the three months ended March 31, 2022.

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The weighted-average assumptions used in the Black-Scholes option pricing model to determine the fair value of the stock option grants were as follows:

As of March 31, 2022, the unrecognized compensation cost related to outstanding options was $13.9 million and is expected to be recognized as expense over approximately 3.3 years.

The weighted average assumptions used in Black-Scholes option pricing model to estimate the fair value of purchase rights granted under the ESPP were as follows:

As of March 31, 2022, there was $0.3 million of unrecognized compensation cost related to the ESPP and is expected to be recognized over approximately 1.3 years.

The determination of the fair value of share-based payment awards utilizing the Black-Scholes option-pricing model is affected by the Company’s stock price and the following assumptions:

Risk-free interest rate. The risk-free interest rate assumption is based on the U.S. Treasury instruments, the terms of which were consistent with the expected term of the Company’s stock-based awards.

Expected volatility. Due to the Company’s limited operating history and lack of company-specific historical or implied volatility, the expected volatility assumption was determined by examining the historical volatilities of a group of industry peers whose share prices are publicly available.

Expected term. The expected term represents the weighted-average period the stock-based awards are expected to be outstanding. The Company uses the simplified method for estimating the expected term. The simplified method calculates the expected term as the average of the time-to-vesting and the contractual life of the stock-based awards.

Expected dividend yield. The expected dividend assumption is based on the Company’s history and expectation of dividend payouts. The Company has not paid and does not intend to pay dividends.

Forfeitures. The Company reduces stock-based compensation expense for actual forfeitures during the period.

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Note 7 – License Agreements

The Company has entered into license agreements, accounted for as asset acquisitions, under which the Company is required to use commercially reasonable efforts to meet certain specified development and regulatory milestones related to the licensed technologies within specified time periods. In consideration of the rights granted to the Company under the agreements, the Company is required to make cash milestone payments to the licensors upon the completion of certain development, regulatory and commercial milestones. For the arrangements that the Company accounted for as asset acquisitions, contingent consideration liabilities are recorded as an additional cost of the acquired assets when the contingency is resolved, and the consideration is paid or becomes payable. Additionally, the Company has agreed to pay royalties on net sales of products applicable to the license agreements. The Company may terminate the agreements upon written notice to the licensors.

Daiichi Sankyo License Agreement

On September 2, 2020, the Company licensed the rights to milademetan (DS-3032b) for all human prophylactic or therapeutic uses in all countries and territories of the world from Daiichi Sankyo Company, Limited, (“Daiichi Sankyo”), a Japanese corporation (the “Daiichi Sankyo License Agreement”). Daiichi Sankyo conducted clinical studies of milademetan prior to the Company’s licensing the rights to this product. The Company refers to this product candidate as milademetan.

In accordance with the terms of the Daiichi Sankyo License Agreement, the Company paid Daiichi Sankyo an initial upfront payment of $5.0 million in September 2020.

Under the Daiichi Sankyo License Agreement, the Company obtained worldwide, sublicensable exclusive rights to seven families of patents with respect to milademetan (the “Licensed Compound”). The Company is solely responsible under the Daiichi Sankyo License Agreement for the research, development and registration of milademetan. Pursuant to the Daiichi Sankyo License Agreement, Daiichi Sankyo had the right to continue to conduct three clinical trials and prepare final reports with respect to these clinical trials, and such right expires upon all subjects completing the study treatment. The Company has agreed to reimburse Daiichi Sankyo certain third-party expenses incurred while conducting such trials. On March 3, 2022, the Company and Daiichi Sankyo entered into a Memorandum of Understanding, which provides that Daiichi Sankyo will terminate its U105 study and the Company will reimburse a total of $2.0 million to Daiichi Sankyo for expenses related to such study in four installments of $500,000 each until December 31, 2022. The Company paid the first installment of $500,000 in April 2022. The future $500,000 installments are payable June 30, September 30, and December 31 of 2022. The Company made other clinical trials payments of $30,000 under the Daiichi Sankyo License Agreement for the three months ended March 31, 2022. The Company made no clinical trials payments to Daiichi Sankyo for the three months ended March 31, 2021. As of March 31, 2022 and December 31, 2021, the accrued Daiichi Sankyo reimbursable clinical trials costs were $2.0 million, which was recorded in accrued research and development in the condensed balance sheet.

The Company is required to make aggregate future milestone payments of up to $224.5 million, contingent on the attainment of certain development, regulatory and sales milestones. The $224.5 million aggregate future milestone payments include a $2.0 million increase that was agreed upon in the Memorandum of Understanding with Daiichi Sankyo. On July 20, 2021, the Company announced that the first patient has been randomized in the multicenter, open-label, Phase 3 registrational trial (MANTRA) evaluating milademetan for the treatment of de-differentiated liposarcoma. Accordingly, pursuant to the Daiichi Sankyo License Agreement, the Company recorded $5.5 million in milestone fees as research and development expense in the condensed statement of operations and comprehensive loss during the three months ended September 30, 2021. Of the $5.5 million milestone fees, $2.5 million was paid in the third quarter of 2021 and $3.0 million was accrued as part of accrued research and development in the condensed balance sheet as of March 31, 2022 and December 31, 2021. During the three months ended March 31, 2022 and 2021, the Company incurred no milestone research and development expense under the Daiichi Sankyo License Agreement (as defined above).

Additionally, the Company is required to pay Daiichi Sankyo a high single digit royalty based on the annual net sales of products containing milademetan as an active pharmaceutical ingredient (the “Products”), subject to reduction at an agreed rate upon expiration of the licensed patent in the particular country where products containing milademetan as an active pharmaceutical ingredient (the “Products”) are sold. To date, no royalty payments have been made to Daiichi Sankyo under the Daiichi Sankyo License Agreement. The royalty obligation terminates on a country-by-country and on a product-by-product basis on the later of: (i) loss of all market exclusivity for such Product in such country, (ii) the last-to-expire patent that covers the Licensed Compound or the Product in such country and (iii) twelve years from launch of the first Product sold by the Company in such country.

Unless sooner terminated or extended, the Daiichi Sankyo License Agreement will remain in full force and effect until the Company, its affiliates and its sublicensees cease all development and commercial activity related to milademetan. Either party may terminate the Daiichi Sankyo License Agreement for cause in the event of an uncured

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material breach (subject to a 90-day cure period). However, the Company may only terminate the Daiichi Sankyo License Agreement with respect to the countries affected by such uncured material breach. Daiichi Sankyo may also terminate the Daiichi Sankyo License Agreement in the event of Rain’s bankruptcy or insolvency. Additionally, Daiichi Sankyo may terminate the Daiichi Sankyo License Agreement immediately upon written notice if the Company, its affiliates or its sublicensors initiate or join any challenge to the validity or enforceability of a licensed patent, subject to certain exclusions. Furthermore, the Company may terminate the Daiichi Sankyo License Agreement in its entirety or on a country-by-country basis for bona fide material concerns regarding the (i) lack of safety for human use arising from toxicity of the Licensed Compound or Product(s), (ii) lack of efficacy of the Licensed Compound or Product(s) or (iii) adverse economic impact to the Company in connection with its continued development of the Products, in each case, upon six months’ prior written notice to Daiichi Sankyo. In addition, if the Company is acquired by a third party that is developing and commercializing a competing compound and the acquiring party decides not to discontinue the development or commercialization of such competing compound, such third party must terminate the Daiichi Sankyo License Agreement within 30 days of such acquisition if it does not discontinue such development or commercialization. Upon termination of the Daiichi Sankyo License Agreement by Daiichi Sankyo for the Company’s uncured material breach or by the Company for its bona fide material concerns regarding the safety, efficacy or adverse economic impacts relating to the Licensed Compound or Products, or its development thereof, the Company is required to, among other actions, if requested by Daiichi Sankyo (i) transfer to Daiichi Sankyo ongoing clinical trials, data, reports, records and materials, (ii) grant to Daiichi Sankyo an exclusive, irrevocable, sublicensable, fully paid-up license under any patents and know-how that are controlled and actually used by the Company at the time of termination in connection with the Products to allow Daiichi Sankyo exploit the Licensed Compound or Products in countries that are affected by the termination, (iii) grant to Daiichi Sankyo an exclusive, irrevocable, sublicensable, fully paid up license to use trademarks that are specific to the Products and (iv) assign any applicable sublicenses.

Drexel License Agreement and Sponsored Research Agreement

On July 30, 2020 (the “Effective Date”), the Company entered into an intellectual property license agreement (the “Drexel License Agreement”) with Drexel University (“Drexel”). Pursuant to the Drexel License Agreement, Drexel granted to the Company (i) a worldwide, exclusive license to make and commercialize products under a single issued patent and two patent applications related to RAD52 inhibitors for the treatment of cancer (the “Patent Rights”) and (ii) a worldwide, nonexclusive license to make, use and commercialize certain technical information and know-how related to the Patent Rights. The license grant includes the right to sublicense after the first anniversary of the Effective Date, subject to express conditions set forth in the Drexel License Agreement.

The Company is obligated to use commercially reasonable efforts to (i) develop, commercialize, market and sell licensed products in a manner consistent with a development plan and (ii) achieve certain milestone events, including, among other things, receiving investigational new drug application (“IND”) approval for a licensed product by the fourth anniversary of the Effective Date. Under the Drexel License Agreement, for a period of five years from the Effective Date, the Company is granted a first option to license Drexel’s rights in certain improvements, developments or inventions developed by Drexel (or jointly by the parties) during the five-year period that are directly related to the licensed products or to RAD52 or compounds that have been generated to specifically target RAD52.

In addition to a one-time, non-refundable initiation fee of $20,000 paid in four equal installments of $5,000 each within ten days after the Effective Date and six, twelve and eighteen months after the Effective Date, the Drexel License Agreement requires the Company to make further payments to Drexel of up to an aggregate of $6.25 million, for the achievement of specified development milestones for certain licensed products. The Company is also required to reimburse Drexel (i) after the filing of the first IND for the first licensed product, for all costs related to the filing, prosecution and maintenance of the Patent Rights accumulated prior to the Effective Date, and (ii) for all reasonable costs related to the filing, prosecution and maintenance of the Patent Rights after the Effective Date. In addition, the Company is also required to pay Drexel, on a quarterly basis, a low single digit royalty on net sales by the Company, its affiliates and sublicensees of certain licensed products, subject to specified reductions and a minimum quarterly royalty payment of up to $6,250.

Lastly, the Company is also obligated to pay Drexel (i) an annual license maintenance fee of $15,000 commencing upon filing of the first IND for a licensed product until the first sale of the first licensed product, (ii) a sublicense fee of low double digits percentage on all consideration received by the Company from its sublicensees, subject to certain reductions and (iii) a one-time transaction fee equal to the actual amount of Drexel’s licensing and legal expenses in connection with the Drexel License Agreement and the Sponsored Research Agreement the parties simultaneously entered into with the Drexel License Agreement (the Sponsored Research Agreement).

The Company made payments of $5,000 and $19,000 under the Drexel License Agreement for the three months ended March 31, 2022 and 2021, respectively.

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Unless sooner terminated or extended, the term of the Drexel License Agreement with respect to any licensed product and country continues until the later of (i) the expiration or abandonment of the last-to-expire valid claim of the Patent Rights that covers the sale of such licensed product in such country, (ii) the expiration of any granted statutory period of marketing and/or data exclusivity for such licensed product that confers upon the Company exclusive commercialization, (iii) the month of the first sale of a generic equivalent of such licensed product in such country and (iv) ten years after the first sale of the first licensed product.

The Company may terminate the Drexel License Agreement at any time by providing 60 days’ prior written notice to Drexel, in which case the Company will be required to cease exploitation of all licensed products, terminate all permitted sublicenses and pay all amounts owed to Drexel under the Drexel License Agreement and the Sponsored Research Agreement through the effective date of termination. Drexel may terminate the Drexel License Agreement for the Company’s uncured material breach (with 30-135 day cure periods), for the Company’s bankruptcy or insolvency, for the Company’s uncured material default under the Sponsored Research Agreement, or if the Company challenges the validity or enforceability of the licensed patent rights.

Roche Clinical Supply Agreement

In December 2021, the Company entered into a clinical supply agreement with Roche for the supply of the anti-Programmed Death Ligand-1 (PD-L1) monoclonal antibody, atezolizumab. Clinical trials are planned to evaluate milademetan, in combination with atezolizumab for the treatment of patients in genetically selected populations. Under this agreement, Rain is the sponsor of the anticipated clinical trials, and Roche will supply atezolizumab. The Company does not have any financial commitments to Roche under this agreement.

Note 8 – Commitments and Contingencies

Leases

In September 2018, the Company entered into a noncancelable operating lease agreement for office space for its corporate headquarters in Newark, California with an initial term of 5.25 years. The lease commenced in January 2019 and ends March 2024. Under the terms of the lease, the Company pays annual base rent, subject to an annual fixed percentage increase of 3% on March 1st of each year. The Company is obligated to pay for its share of direct expenses including operating expense and taxes, which are considered variable lease costs and are expensed as incurred.

In March 2020, Governor Newsom issued State of California Executive Order No. N-33-20 instructing all individuals in California to stay at home due to the COVID-19 pandemic. In connection with such order, the Company entered into an amendment to the noncancelable operating lease agreement in June 2020. The amendment provided the Company rent relief for three months in 2020. In consideration of the rent relief, the Company agreed to adjust the base rent annual fixed percentage increase of 3% on February 1st of each year and extend the lease until September 2024. The amendment was determined to be a lease modification that qualified as a change of accounting on the existing lease and not a separate contract. Remeasurement of the right-of-use asset and operating lease liabilities at the date of modification did not result in a material increase of the right-of-use asset and operating lease liabilities.

The future minimum lease payments required under the operating lease are summarized as follows (in thousands):

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The table below summarizes the Company’s lease costs and cash payments in connection with operating lease obligations (in thousands):

Contingencies

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.

Note 9 – Employee Benefits

The Company has a defined contribution 401(k) plan available to eligible employees. Under the terms of the plan, employees may make voluntary contributions as a percent of compensation, limited to the maximum amount allowable under federal tax regulations. The Company, at its discretion, may make certain contributions to the 401(k) plan. The Company made matching contributions of $75,000 and $78,000 for the three months ended March 31, 2022 and 2021, respectively.

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: