Financial Analysis

15. Commitments and Contingencies License Agreements The Company is obligated to pay royalties pursuant to the Vitae License Agreement and the UCB License Agreement as a percentage of net product sales for direct licensed products, such as Revuforj and Niktimvo. The obligation to pay royalties expires, on a country-by-country basis and licensed product-by-licensed product basis at the later of (i) the expiration of all of the licensed patent rights in such country; (ii) the expiration of all regulatory exclusivity applicable to the product in such country; and (iii) 10 years from the date of the first commercial sale of the product in such country. These fees were recorded as cost of product sales. From time to time, the Company may be subject to various claims and proceedings in the ordinary course of business. If the potential loss from any claim, asserted or unasserted, or proceeding is considered probable and the amount is reasonably estimable, the Company will accrue a liability for the estimated loss. There were no contingent liabilities recorded as of March 31, 2026

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13. Stock-Based Compensation In January 2026, the number of shares of common stock available for issuance under the Companys 2015 Omnibus Incentive Plan, or the 2015 Plan, was increased by 3,496,239 shares of common stock due to the automatic annual provision to increase shares of common stock available under the 2015 Plan. In March 2026, the 2015 Plan expired. As of March 31, 2026, there were 754,528 shares of common stock available for issuance under the Inducement Plan. The Company recognized stock-based compensation expense related to the issuance of stock option awards and restricted stock units to employees and non-employees and related to the Companys 2015 Employee Stock Purchase Plan, or ESPP, in the consolidated statements of comprehensive loss as follows: Three Months Ended March 31, 2026 2025 Research and development $ 4,027 $ 3,668 Selling, general and administrative 8,026 6,712 Total $ 12,053 $ 10,380 Compensation expense by type of award in the three months ended March 31, 2026 and 2025 was as follows: Three Months Ended March 31, 2026 2025 Stock options $ 7,561 $ 7,685 RSUs 4,281 2,575 ESPP 211 120 Total $ 12,053 $ 10,380 In addition, stock-based compensation exp ense of $ 0.1 million was ca pitalized to inventory as of March 31, 2026 and 2025, which represents the stock-based compensation expense incurred related to employees involved in the manufacturing process of finished goods and samples. As of March 31, 2026, there were $ 113.5 million of unrecognized co …

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Recently Issued and Adopted Accounting Pronouncements From time to time, new accounting pronouncements are issued by the FASB or other accounting standard setting bodies that we adopt as of the specified effective date. Unless otherwise discussed below, we do not believe that the adoption of recently issued standards have or may have a material impact on our unaudited consolidated financial statements or disclosures. In November 2024, the FASB issued ASU 2024-03, Income StatementReporting Comprehensive IncomeExpense Disaggregation Disclosures (Subtopic 220-40): Disaggregation of Income Statement Expenses, or ASU 2024-03 . Among other items, the requirements include expanded disclosures around employee compensation and selling expenses. ASU 2024-03 will be effective for the Company for the year ending December 31, 2027. The Company is still evaluating the impact of this new guidance on its unaudited consolidated financial statements but expects the adoption to result in disclosure changes only. …

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16. Segment Reporting The Company manages its business activities on a consolidated basis and operate as a single operating and reportable segment: Syndax Pharmaceuticals. The Company primarily derives revenue in the United States through milestone revenue and product sales on the approved products, Revuforj (revumenib) and Niktimvo (axatilimab-csfr). The accounting policies of the segment are the same as those described in Note 3 Summary of Significant Accounting Policies. To assess performance, the Companys Chief Operating Decision Maker, or CODM, Michael Metzger, uses consolidated net loss as the segments measure of segment profit or loss. The CODM uses net loss in the budget and forecasting process and considers budget-to actual variances on a quarterly basis when making decisions about the allocation of operating and capital resources. The following table provides the operating financial results of our biopharmaceutical cancer therapeutics segment: Three Months Ended March 31, 2026 2025 March 31, 2026 Total Revenue $ 64,864 $ 20,042 Less: Significant and other segment expenses Cost of product sales 2,633 885 Collaboration loss - 247 Research and development expenses Revumenib-related costs 25,725 20,805 Axatilimab-related costs 9,633 19,711 Other R&D programs 162 921 Personnel cost and other expenses 19,298 16,531 General and administrative expenses Commercial related expenses 7,721 10,825 Personnel cost and other expenses 16,701 19,082 Other SG&A expenses 5,140 …

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3. Summary of Significant Accounting Policies The Companys significant accounting policies, which are disclosed in the audited consolidated financial statements for the year ended December 31, 2025, and the notes thereto are included in the Companys Annual Report on Form 10-K that was filed with the SEC on February 26, 2026. Since the date of filing, there have been no material changes to the Companys significant accounting policies, except as noted below. Use of Estimates The preparation of the unaudited consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and the disclosure of contingent assets and liabilities at the date of the unaudited consolidated financial statements and the reported amounts of costs and expenses during the reporting period. The Company bases estimates and assumptions on historical experience when available and on various factors that it believes to be reasonable under the circumstances. The Company evaluates its estimates and assumptions on an ongoing basis. Estimates and assumptions about future events and their effects cannot be determined with certainty and therefore require the exercise of judgment. As of the date of issuance of these unaudited consolidated financial statements, the Company is not aware of any specific event or circumstance that would require the Company to update its estimates, assumptions and judgments or re …

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14. Stockholders Equity Pre-Funded Warrants In December 2021, the Company sold pre-funded warrants to purchase 1,142,856 shares of common stock. As of March 31, 2026, 285,714 pre-funded warrants were issued and outstanding. …

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