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UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 10-Q

(Mark One)

☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

For the quarterly period ended June 30, 2026

or

☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

For the transition period from to

Commission File Number: 001-37708

Syndax Pharmaceuticals, Inc.

(Exact Name of Registrant as Specified in Its Charter)

Delaware | 32-0162505
(State or Other Jurisdiction of Incorporation or Organization) | (IRS Employer Identification No.)
730 Third Avenue, 9th Floor New York, New York | 10017
(Address of Principal Executive Offices) | (Zip Code)

(781) 419-1400

(Registrant’s Telephone Number, Including Area Code)

Securities registered pursuant to Section 12(b) of the Act:

Title of each class | Trading Symbol(s) | Name of each exchange on which registered
Common Stock | SNDX | The Nasdaq Stock Market, LLC

Indicate by check mark whether the registrant: (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days. Yes ☒ No ☐

Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T (Section 232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit such files). Yes ☒ No ☐

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, smaller reporting company, or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company,” and “emerging growth company” in Rule 12b-2 of the Exchange Act.:

Large accelerated filer | ☒ |  | Accelerated filer | ☐
Non-accelerated filer | ☐ |  | Smaller reporting company | ☐
Emerging growth company | ☐ |  |  |

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act). Yes ☐ No ☒

As of July 31, 2026, there were 89,297,086 shares o f the registrant’s Common Stock, par value $0.0001 per share, outstanding.

g

FORWARD-LOOKING STATEMENTS

This Quarterly Report on Form 10-Q, or this Quarterly Report, contains forward-looking statements and information within the meaning of Section 27A of the Securities Act of 1933, as amended, and Section 21E of the Securities Exchange Act of 1934, as amended, which are subject to the "safe harbor" created by those sections. All statements other than statements of historical fact are “forward-looking statements” for purposes of this Quarterly Report. In some cases, you can identify forward-looking statements by terminology such as “anticipate,” “believe,” “could,” “estimate,” “expects,” “intend,” “may,” “plan,” “potential,” “predict,” “project,” “should,” “will,” “would” or the negative or plural of those terms, and similar expressions.

Forward-looking statements include, but are not limited to, statements about:

•
our estimates regarding our expenses, future revenues, anticipated capital requirements and our needs for additional financing;
•
the initiation, cost, timing, progress and results of our research and development activities, clinical trials and preclinical studies;
•
our ability to replicate results in future clinical trials;
•
our expectations regarding the potential safety, efficacy or clinical utility of our products and product candidates as well as the potential use of our products and product candidates to treat various cancer indications and fibrotic diseases;
•
our ability to obtain and maintain regulatory approval for our products and product candidates and the timing or likelihood of regulatory filings and approvals for such candidates;
•
our indebtedness as well as the ability to meet our cash payment obligations under the outstanding convertible notes from our business cash flows;
•
the operating and financial restrictions imposed on us under the Indenture related to our outstanding convertible notes;
•
our ability to maintain our licenses with UCB Biopharma Sprl, and Vitae Pharmaceuticals, LLC, a subsidiary of AbbVie Inc.;
•
the success of our collaboration with Incyte Corporation, or Incyte, to further develop and commercialize axatilimab;
•
the potential milestone and royalty payments under certain of our license agreements;
•
the implementation of our strategic plans for our business and development of our products and product candidates;
•
the scope of protection we establish and maintain for intellectual property rights covering our products, product candidates and our technology;
•
the market adoption of REVUFORJ® (revumenib) and NIKTIMVO™ (axatilimab-csfr) and our other product candidates by physicians and patients;
•
developments relating to our competitors and our industry; and
•
the impact of geopolitical actions, including tariffs, wars or terrorism or the perception that hostilities may be imminent, adverse global economic conditions, terrorism, public health crises, funding shortages at governmental and regulatory agencies on which we rely, or natural disasters on our operations, research and development and clinical trials and potential disruption in the operations and business of third-party manufacturers, contract research organizations, or CROs, other service providers, and collaborators with whom we conduct business.

These statements are only current predictions and are subject to known and unknown risks, uncertainties and other factors that may cause our or our industry’s actual results, levels of activity, performance, or achievements to be materially different from those anticipated by the forward-looking statements. We discuss many of these risks in this report in greater detail in the section titled “Risk Factors” and elsewhere in this report. You should not rely upon forward-looking statements as predictions of future events.

Although we believe that the expectations reflected in the forward-looking statements are reasonable, we cannot guarantee future results, levels of activity, performance, or achievements. Except as required by law, we are under no duty to update or revise any of the forward-looking statements, whether as a result of new information, future events or otherwise.

ii

TABLE OF CONTENTS

|  |  |  | Page
PART I. FINANCIAL INFORMATION |  |
Item 1. |  | Unaudited Financial Statements: |  |
|  | Consolidated Balance Sheets as of June 30, 2026 and December 31, 2025 |  | 1
|  | Consolidated Statements of Comprehensive Loss for the three and six months ended June 30, 2026 and 2025 |  | 2
|  | Consolidated Statements of Changes in Stockholders' Equity for the three and six months ended June 30, 2026 and 2025 |  | 3
|  | Consolidated Statements of Cash Flows for the six months ended June 30, 2026 and 2025 |  | 4
|  | Notes to Consolidated Financial Statements |  | 5
Item 2. |  | Management’s Discussion and Analysis of Financial Condition and Results of Operations |  | 17
Item 3. |  | Quantitative and Qualitative Disclosures About Market Risk |  | 27
Item 4. |  | Controls and Procedures |  | 27
PART II. OTHER INFORMATION |  |
Item 1. |  | Legal Proceedings |  | 29
Item 1A. |  | Risk Factors |  | 29
Item 5. |  | Other Information |  | 31
Item 6. |  | Exhibits |  | 32

c

iii

Part I: FINANCI AL INFORMATION

Item 1: Financi al Statements

SYNDAX PHARMACEUTICALS, INC.

(unaudited)

CONSOLIDAT ED BALANCE SHEETS

(In thousands, except share and per share data)

|  | June 30, 2026 |  |  | December 31, 2025 |
ASSETS |  |  |  |  |  |
Current assets: |  |  |  |  |  |
Cash and cash equivalents |  | $ | 336,477 |  |  | $ | 134,930 |
Short-term investments |  |  | 211,383 |  |  |  | 259,140 |
Accounts receivable, net |  |  | 45,067 |  |  |  | 37,996 |
Inventory, net |  |  | 33,164 |  |  |  | 32,754 |
Short-term deposits |  |  | 6,406 |  |  |  | 19,616 |
Other receivables, net |  |  | 2,703 |  |  |  | 6,404 |
Collaboration receivable, net |  |  | 22,359 |  |  |  | 23,745 |
Prepaid expenses and other current assets |  |  | 17,480 |  |  |  | 13,496 |
Total current assets |  |  | 675,039 |  |  |  | 528,081 |
Long-term investments |  |  | 27,217 |  |  |  | — |
Property and equipment, net |  |  | 212 |  |  |  | 181 |
Right-of-use asset, net |  |  | 1,082 |  |  |  | 1,342 |
Restricted cash |  |  | 102 |  |  |  | 102 |
Total assets |  | $ | 703,652 |  |  | $ | 529,706 |
LIABILITIES AND STOCKHOLDERS’ EQUITY |  |  |  |  |  |
Current liabilities: |  |  |  |  |  |
Accounts payable |  | $ | 4,874 |  |  | $ | 16,580 |
Accrued expenses and other current liabilities |  |  | 94,297 |  |  |  | 103,064 |
Current portion of right-of-use liability |  |  | 506 |  |  |  | 470 |
Current portion of capital lease |  |  | — |  |  |  | 2 |
Total current liabilities |  |  | 99,677 |  |  |  | 120,116 |
Long-term liabilities: |  |  |  |  |  |
Royalty interest financing liability |  |  | 344,026 |  |  |  | 343,909 |
Convertible note liability |  |  | 244,090 |  |  |  | — |
Right-of-use liability, less current portion |  |  | 760 |  |  |  | 1,051 |
Total long-term liabilities |  |  | 588,876 |  |  |  | 344,960 |
Total liabilities |  |  | 688,553 |  |  |  | 465,076 |
Commitments and contingencies (Note 16) |  |  |  |  |  |
Stockholders’ equity: |  |  |  |  |  |
Common stock, $0.0001 par value, 200,000,000 shares authorized; 89,150,619 and 87,405,979 shares issued and outstanding at June 30, 2026 and December 31, 2025, respectively |  |  | 9 |  |  |  | 9 |
Additional paid-in capital |  |  | 1,613,846 |  |  |  | 1,570,749 |
Accumulated other comprehensive (loss) gain |  |  | (140 | ) |  |  | 452 |
Accumulated deficit |  |  | (1,598,616 | ) |  |  | (1,506,580 | )
Total stockholders’ equity |  |  | 15,099 |  |  |  | 64,630 |
Total liabilities and stockholders’ equity |  | $ | 703,652 |  |  | $ | 529,706 |

The accompanying notes are an integral part of these unaudited consolidated financial statements.

1

SYNDAX PHARMACEUTICALS, INC.

(unaudited)

CONSOLIDATED STATE MENTS OF COMPREHENSIVE LOSS

(In thousands, except share and per share data)

| Three Months Ended June 30, |  |  | Six Months Ended June 30, |
| 2026 |  |  | 2025 |  |  | 2026 |  |  | 2025 |
Revenue: |  |  |  |  |  |  |  |  |  |  |
Product revenue, net | $ | 54,700 |  |  | $ | 28,600 |  |  | $ | 103,623 |  |  | $ | 48,642 |
Collaboration revenue, net |  | 18,088 |  |  |  | 9,358 |  |  |  | 34,029 |  |  |  | 9,111 |
Total revenues |  | 72,788 |  |  |  | 37,958 |  |  |  | 137,652 |  |  |  | 57,753 |
Operating expenses: |  |  |  |  |  |  |  |  |  |  |
Cost of product sales | $ | 3,208 |  |  | $ | 1,279 |  |  | $ | 5,841 |  |  | $ | 2,164 |
Research and development |  | 68,036 |  |  |  | 62,227 |  |  |  | 126,881 |  |  |  | 123,863 |
Selling, general and administrative |  | 41,539 |  |  |  | 43,805 |  |  |  | 79,127 |  |  |  | 84,836 |
Total operating expenses |  | 112,783 |  |  |  | 107,311 |  |  |  | 211,849 |  |  |  | 210,863 |
Loss from operations |  | (39,995 | ) |  |  | (69,353 | ) |  |  | (74,197 | ) |  |  | (153,110 | )
Other (expense) income, net: |  |  |  |  |  |  |  |  |  |  |
Royalty interest expense |  | (12,119 | ) |  |  | (7,854 | ) |  |  | (23,965 | ) |  |  | (15,903 | )
Convertible note interest expense |  | (555 | ) |  |  | — |  |  |  | (555 | ) |  |  | — |
Other interest expense |  | (2 | ) |  |  | (4 | ) |  |  | (2 | ) |  |  | (6 | )
Interest income |  | 3,746 |  |  |  | 5,950 |  |  |  | 7,307 |  |  |  | 13,133 |
Other expense |  | (438 | ) |  |  | (586 | ) |  |  | (624 | ) |  |  | (807 | )
Total other (expense) income, net |  | (9,368 | ) |  |  | (2,494 | ) |  |  | (17,839 | ) |  |  | (3,583 | )
Net loss | $ | (49,363 | ) |  | $ | (71,847 | ) |  | $ | (92,036 | ) |  | $ | (156,693 | )
Other comprehensive loss: |  |  |  |  |  |  |  |  |  |  |
Unrealized (loss) gain on marketable securities |  | (151 | ) |  |  | (242 | ) |  |  | (592 | ) |  |  | 122 |
Other comprehensive loss |  | (49,514 | ) |  |  | (72,089 | ) |  |  | (92,628 | ) |  |  | (156,571 | )
Net loss per share: |  |  |  |  |  |  |  |  |  |  |
Basic and diluted loss per share attributable to common stockholders | $ | (0.55 | ) |  | $ | (0.83 | ) |  | $ | (1.04 | ) |  | $ | (1.82 | )
Weighted-average common shares used in calculating: |  |  |  |  |  |  |  |  |  |  |
Basic and diluted loss per share attributable to common stockholders |  | 88,991,317 |  |  |  | 86,337,237 |  |  |  | 88,625,508 |  |  |  | 86,255,020 |

The accompanying notes are an integral part of these unaudited consolidated financial statements.

2

SYNDAX PHARMACEUTICALS, INC.

(unaudited)

CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY

(In thousands, except share and per share data)

Six months ended June 30, 2026 |
(In thousands, except share data) |  | Common Stock $0.0001 Par Value |  |  | Additional Paid-In Capital |  |  | Accumulated Other Comprehensive (Loss)/Income |  |  | Accumulated Deficit |  |  | Total Stockholders’ Equity |
|  | Shares |  |  | Amount |  |  |  |  |  |  |  |  |  |  |  |  |
Balance as of December 31, 2025 |  |  | 87,405,979 |  |  | $ | 9 |  |  | $ | 1,570,749 |  |  | $ | 452 |  |  | $ | (1,506,580 | ) |  | $ | 64,630 |
Stock-based compensation expense |  |  | — |  |  |  | — |  |  |  | 12,188 |  |  |  | — |  |  |  | — |  |  |  | 12,188 |
Unrealized loss on investments |  |  | — |  |  |  | — |  |  |  | — |  |  |  | (441 | ) |  |  | — |  |  |  | (441 | )
Stock purchase under ESPP |  |  | 120,458 |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |
Employee withholdings ESPP |  |  | — |  |  |  | — |  |  |  | 458 |  |  |  | — |  |  |  | — |  |  |  | 458 |
Vesting of RSUs |  |  | 506,135 |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |
Proceeds from exercise of stock options |  |  | 511,309 |  |  |  | — |  |  |  | 7,460 |  |  |  | — |  |  |  | — |  |  |  | 7,460 |
Net loss |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | (42,673 | ) |  |  | (42,673 | )
Balance as of March 31, 2026 |  |  | 88,543,881 |  |  | $ | 9 |  |  | $ | 1,590,855 |  |  | $ | 11 |  |  | $ | (1,549,253 | ) |  | $ | 41,622 |
Stock-based compensation expense |  |  | — |  |  |  | — |  |  |  | 14,069 |  |  |  | — |  |  |  | — |  |  |  | 14,069 |
Unrealized loss on investments |  |  | — |  |  |  | — |  |  |  | — |  |  |  | (151 | ) |  |  | — |  |  |  | (151 | )
Vesting of RSUs |  |  | 44,250 |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |
Employee withholdings ESPP |  |  | — |  |  |  | — |  |  |  | 167 |  |  |  | — |  |  |  | — |  |  |  | 167 |
Proceeds from exercise of stock options |  |  | 562,488 |  |  |  | — |  |  |  | 8,755 |  |  |  | — |  |  |  | — |  |  |  | 8,755 |
Net loss |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | (49,363 | ) |  |  | (49,363 | )
Balance as of June 30, 2026 |  |  | 89,150,619 |  |  |  | 9 |  |  |  | 1,613,846 |  |  |  | (140 | ) |  |  | (1,598,616 | ) |  |  | 15,099 |

The accompanying notes are an integral part of these unaudited consolidated financial statements.

3

SYNDAX PHARMACEUTICALS, INC.

(unaudited)

CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY

(In thousands, except share and per share data)

Six months ended June 30, 2025 |
(In thousands, except share data) |  | Common Stock $0.0001 Par Value |  |  | Additional Paid-In Capital |  |  | Accumulated Other Comprehensive (Loss)/Income |  |  | Accumulated Deficit |  |  | Total Stockholders’ Equity |
|  | Shares |  |  | Amount |  |  |  |  |  |  |  |  |  |  |  |  |
Balance as of December 31, 2024 |  |  | 85,694,443 |  |  | $ | 9 |  |  | $ | 1,509,110 |  |  | $ | 163 |  |  | $ | (1,221,158 | ) |  | $ | 288,124 |
Stock purchase under ESPP |  |  | 104,115 |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |
Stock-based compensation expense |  |  | — |  |  |  | — |  |  |  | 10,487 |  |  |  | — |  |  |  | — |  |  |  | 10,487 |
Unrealized gain on investments |  |  | — |  |  |  | — |  |  |  | — |  |  |  | 364 |  |  |  | — |  |  |  | 364 |
Vesting of RSUs |  |  | 205,527 |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |
Employee withholdings ESPP |  |  | — |  |  |  | — |  |  |  | 545 |  |  |  | — |  |  |  | — |  |  |  | 545 |
Proceeds from exercise of stock options |  |  | 42,947 |  |  |  | — |  |  |  | 385 |  |  |  | — |  |  |  | — |  |  |  | 385 |
Net loss |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | (84,846 | ) |  |  | (84,846 | )
Balance as of March 31, 2025 |  |  | 86,047,032 |  |  | $ | 9 |  |  | $ | 1,520,527 |  |  | $ | 527 |  |  | $ | (1,306,004 | ) |  | $ | 215,059 |
Stock-based compensation expense |  |  | — |  |  |  | — |  |  |  | 13,903 |  |  |  | — |  |  |  | — |  |  |  | 13,903 |
Unrealized loss on investments |  |  | — |  |  |  | — |  |  |  | — |  |  |  | (242 | ) |  |  | — |  |  |  | (242 | )
Vesting of RSUs |  |  | 417 |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |
Employee withholdings ESPP |  |  | — |  |  |  | — |  |  |  | 468 |  |  |  | — |  |  |  | — |  |  |  | 468 |
Proceeds from exercise of stock options |  |  | 11,628 |  |  |  | — |  |  |  | 83 |  |  |  | — |  |  |  | — |  |  |  | 83 |
Net loss |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |  |  |  | (71,847 | ) |  |  | (71,847 | )
Balance as of June 30, 2025 |  |  | 86,059,077 |  |  | $ | 9 |  |  | $ | 1,534,981 |  |  | $ | 285 |  |  | $ | (1,377,851 | ) |  | $ | 157,424 |

The accompanying notes are an integral part of these unaudited consolidated financial statements.

4

SYNDAX PHARMACEUTICALS, INC.

(unaudited)

CONSOLIDATED S TATEMENTS OF CASH FLOWS

(In thousands)

|  | Six Months Ended June 30, |
|  | 2026 |  |  | 2025 |
CASH FLOWS FROM OPERATING ACTIVITIES: |  |  |  |  |  |
Net loss |  | $ | (92,036 | ) |  | $ | (156,693 | )
Adjustments to reconcile net loss to net cash used in operating activities: |  |  |  |  |  |
Depreciation |  |  | 9 |  |  |  | — |
Accretion of investments |  |  | (1,568 | ) |  |  | (6,810 | )
Non-cash operating lease expense |  |  | 260 |  |  |  | 393 |
Stock-based compensation |  |  | 26,067 |  |  |  | 24,167 |
Non-cash interest on convertible note |  |  | 555 |  |  |  | — |
Amortization of debt issuance costs |  |  | 359 |  |  |  | 167 |
Changes in operating assets and liabilities: |  |  |  |  |  |
Accounts receivable |  |  | (7,071 | ) |  |  | (11,852 | )
Inventory, net |  |  | (220 | ) |  |  | (17,107 | )
Prepaid expenses and other assets |  |  | 9,226 |  |  |  | (4,778 | )
Collaboration receivable (payable), net |  |  | 1,386 |  |  |  | (31,547 | )
Other receivable |  |  | 3,701 |  |  |  | 6 |
Accounts payable |  |  | (11,706 | ) |  |  | 5,727 |
Accrued expenses and other liabilities |  |  | (9,579 | ) |  |  | 15,370 |
Net cash used in operating activities |  |  | (80,617 | ) |  |  | (182,957 | )
CASH FLOWS FROM INVESTING ACTIVITIES: |  |  |  |  |  |
Purchases of property, plant, and equipment |  |  | (40 | ) |  |  | — |
Purchases of short and long-term investments |  |  | (125,261 | ) |  |  | (102,251 | )
Proceeds from sales and maturities of short-term investments |  |  | 146,777 |  |  |  | 238,280 |
Net cash provided by investing activities |  |  | 21,476 |  |  |  | 136,029 |
CASH FLOWS FROM FINANCING ACTIVITIES: |  |  |  |  |  |
Proceeds from convertible note |  |  | 250,000 |  |  |  | — |
Issuance costs of convertible note |  |  | (6,152 | ) |  |  | — |
Proceeds from Employee Stock Purchase Plan |  |  | 625 |  |  |  | 1,013 |
Proceeds from stock option exercises |  |  | 16,215 |  |  |  | 468 |
Net cash provided by financing activities |  |  | 260,688 |  |  |  | 1,481 |
NET INCREASE (DECREASE) IN CASH, CASH EQUIVALENTS AND RESTRICTED CASH |  |  | 201,547 |  |  |  | (45,447 | )
CASH, CASH EQUIVALENTS AND RESTRICTED CASH—beginning of period |  |  | 135,032 |  |  |  | 154,300 |
CASH, CASH EQUIVALENTS AND RESTRICTED CASH —end of period |  | $ | 336,579 |  |  | $ | 108,853 |
SUPPLEMENTAL DISCLOSURE OF CASH FLOW INFORMATION: |  |  |  |  |  |
Cash paid for royalty interest financing |  | $ | 15,332 |  |  | $ | 1,879 |

The accompanying notes are an integral part of these unaudited consolidated financial statements.

5

SYNDAX PHARMACEUTICALS, INC.

(unaudited)

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS

1. Nature of Business

Syndax Pharmaceuticals, Inc. is a commercial-stage biopharmaceutical company advancing innovative cancer therapies. We currently have two commercially approved products and a robust pipeline of late- and early-stage development programs. We were incorporated in Delaware in 2005. We have operations in New York, NY, and we operate in one segment. References in these notes to unaudited consolidated financial statements to “Syndax,” “the Company,” “we,” “us” or “our” refer to Syndax Pharmaceuticals, Inc. and its wholly owned subsidiaries.

2. Basis of Presentation

The accompanying unaudited consolidated financial statements have been prepared in conformity with U.S. generally accepted accounting principles, or U.S. GAAP. Any reference in these notes to applicable guidance is meant to refer to U.S. GAAP as found in the Accounting Standards Codification, or ASC, and Accounting Standards Updates, or ASU, of the Financial Accounting Standards Board, or FASB.

In the opinion of management, the accompanying unaudited interim financial statements include all normal and recurring adjustments (which consist primarily of accruals and estimates that impact the financial statements) considered necessary to present fairly the Company’s financial position as of June 30, 2026 and its results of operations for the three and six months ended June 30, 2026 and 2025 and cash flows for the six months ended June 30, 2026 and 2025. Operating results for the three and six months ended June 30, 2026 are not necessarily indicative of the results that may be expected for the year ending December 31, 2026. The unaudited interim financial statements presented herein do not contain the required disclosures under U.S. GAAP for annual financial statements. The accompanying unaudited interim financial statements should be read in conjunction with the annual audited financial statements and related notes as of and for the year ended December 31, 2025 contained in the Company’s Annual Report on Form 10-K, filed with the Securities and Exchange Commission, or SEC, on February 26, 2026.

In 2011, the Company established a wholly owned subsidiary in the United Kingdom, which the Company dissolved in June 2024. In 2014, the Company established a wholly owned U.S. subsidiary, which the Company dissolved in July 2025. In 2021, the Company established a wholly owned subsidiary in the Netherlands. To date, there have been no material activities for these entities. All intercompany balances and transactions have been eliminated in consolidation.

3. Summary of Significant Accounting Policies

The Company’s 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 Company’s 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 Company’s 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 revise the carrying value of its assets or liabilities. These estimates may change as new events occur and additional information is obtained and are recognized in the unaudited consolidated financial statements as soon as they become known. Actual results could differ from those estimates and any such differences may be material to the Company’s unaudited consolidated financial statements.

Income taxes

In accordance with Topic ASC 270, Interim Reporting, and Topic ASC 740, Income Taxes, the Company is required at the end of each interim period to determine the best estimate of its annual effective tax rate and then apply that rate in providing for income taxes on a current year-to-date (interim period) basis. For the six months ended June 30, 2026 and 2025, the Company

6

recorded no tax expense or benefit due to the expected current year loss and its historical losses. As of June 30, 2026 and December 31, 2025, the Company concluded that a full valuation allowance would be necessary for all of its net deferred tax assets. The Company had no amounts recorded for uncertain tax positions, interest or penalties in the accompanying unaudited consolidated financial statements.

On July 4, 2025, the One Big Beautiful Bill Act, or OBBBA, was enacted in the United States. The OBBBA includes significant changes to the Internal Revenue Code of 1986, such as the permanent extension of certain expiring provisions of the Tax Cuts and Jobs Act of 2017, modifications to certain aspects of the international tax framework and the restoration of favorable tax treatment for certain business expense provisions. The OBBBA introduced several U.S. tax law changes, including the ability to immediately expense domestic research and experimental, or R&E, expenditures starting in 2025, and an election to accelerate any unamortized domestic R&E expenditures over a one or two year period beginning with the 2025 tax year. In accordance with ASC 740, Accounting for Income Taxes, the impacts of the OBBBA did not affect the Company’s U.S. deferred tax assets or liabilities, as the Company continues to maintain a full valuation allowance against those balances.

Other comprehensive income

Comprehensive loss consists of two components, net loss and other comprehensive loss, net of tax. The Company’s other comprehensive loss, net of tax, consists of unrealized gains (losses) on the Company’s investments.

Collaboration revenue, net

In September 2021, the Company entered into the Incyte License and Collaboration Agreement, or the Incyte License, with Incyte, covering the worldwide development and commercialization of axatilimab. In August 2024, the U.S. Food and Drug Administration, or FDA, approved Niktimvo for the treatment of chronic graft-versus host disease, or cGVHD, after failure of at least two prior lines of systemic therapy in adult and pediatric patients weighing at least 40 kg (88.2 lbs). See Note 4 — Significant Collaborative Research and License Agreements — Incyte Collaboration for further details on the Incyte License and Collaboration Agreement.

In accordance with Topic ASC 808, Collaboration Arrangements, Incyte has been identified as the principal in product sales, therefore, the Company will recognize its share of any profits or losses in the amount of net product sales less cost of goods sold and shared commercial costs, royalties and other expenses, in the period in which the underlying sales and costs are recognized. The Company’s share of net profits in connection with commercialization of products will be presented as “Collaboration revenue, net” and its share of net losses will be presented as “Collaboration loss, net” within operating expenses. The year to date “Collaboration revenue, net” or “Collaboration loss, net” will be presented as the net cumulative amount for all periods reported on in the financial statements. Th e Company will continue to recognize the costs associated with ongoing development services in the R&D operating expense line, including any cost-sharing components with Incyte.

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 Statement—Reporting Comprehensive Income—Expense 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.

4. Significant Collaborative Research and License Agreements

Incyte Collaboration

In September 2021, the Company entered into the Incyte License with Incyte, covering the worldwide development and commercialization of axatilimab. Also in September 2021, the Company entered into a share purchase agreement with Incyte, or the Incyte Share Purchase Agreement. These agreements are collectively referred to as the Incyte Agreements. Under the terms of the Incyte Agreements, Incyte received exclusive commercialization rights outside of the United States, subject to certain royalty payment obligations set forth below. In the United States, Incyte and the Company are co-commercializing and co-promoting axatilimab as

7

Niktimvo™ (axatilimab-csfr). The Company and Incyte share equally the profits and losses from co-commercialization efforts in the United States.

The Company and Incyte have agreed to continue to co-develop axatilimab and to share development costs associated with global and additional U.S.-specific clinical trials, with Incyte responsible for 55% of such costs and the Company responsible for 45% of such costs. Each company will be responsible for funding any of its own independent development activities. Incyte is responsible for 100% of future development costs for trials that are specific to ex-U.S. countries. All development costs related to the collaboration will be subject to a joint development plan.

Under the terms of the Incyte Agreements, in December 2021, Incyte paid the Company a non-refundable cash payment of $117.0 million and the Company issued 1,421,523 shares of common stock with an aggregate purchase price of $35.0 million, or $24.62 per share. Additionally, under the terms of the Incyte Agreements, the Company is eligible to receive up to $220.0 million in future contingent development and regulatory milestones and up to $230.0 million in commercialization milestones as well as tiered royalties ranging in the mid-teens percentage on net sales of the licensed product comprising axatilimab in Europe and Japan and low double digit percentage in the rest of the world outside of the United States. The Company’s right to receive royalties in any particular country will expire upon the last to occur of (a) the expiration of licensed patent rights covering the licensed product in that particular country, (b) a specified period of time after the first post-marketing authorization sale of a licensed product in that country, and (c) the expiration of any regulatory exclusivity for that licensed product in that country.

In August 2024, the FDA approved Niktimvo for the treatment of cGVHD after failure of at least two prior lines of systemic therapy in adult and pediatric patients weighing at least 40 kg (88.2 lbs). As a result of the approval of Niktimvo, the Company earned a revenue milestone of $12.5 million, which was received in the third quarter of 2024. Upon the achievement of $150.0 million in net sales of Niktimvo, the Company recognized a $5.0 million milestone receivable in the fourth quarter of 2025, which was received in the first quarter of 2026.

For the three and six months ended June 30, 2026, the Company has recognized collaboration revenue of $18.1 million and $34.0 million, respectively. For the three and six months ended June 30, 2025, the Company recognized $9.4 million and $9.1 million of collaboration revenue, respectively. As of June 30, 2026, the Company has recorded approximately $26.4 million as a collaboration receivable due from Incyte related to the Company's portion of the profit share, commercialization and development costs under the Incyte Agreements and has recorded approximately $4.0 million as a collaboration payable due to Incyte for development and commercialization costs incurred by Incyte. As of December 31, 2025, the Company has recorded $28.1 million as a collaboration receivable due from Incyte related to the Company's portion of the profit share, commercialization and development costs under the Incyte Agreements and has recorded approximately $4.4 million as a collaboration payable due to Incyte for development and commercialization costs incurred by Incyte.

The Company’s share of collaboration profit or loss is based on net sales of Niktimvo and the collaborative commercialization expenses.

Vitae Pharmaceuticals, Inc.

In October 2017, the Company entered into a license agreement, or the Vitae License Agreement, with Vitae Pharmaceuticals, Inc., or Vitae, a subsidiary of AbbVie, Inc., or AbbVie, under which the Company was granted an exclusive, sublicensable, worldwide license to a portfolio of preclinical, orally available, small molecule inhibitors of the Menin–KMT2A binding interaction, or the Menin Assets. Upon execution of the Vitae License Agreement, the Company agreed to pay Allergan (the predecessor in interest to AbbVie) up to $99.0 million in one-time development a nd regulatory milestone payments over the term of the Vitae License Agreement, subject to the achievement of certain milestone events. In the event that the Company or any of its affiliates or sublicensees commercializes the Menin Assets, the Company will also be obligated to pay Vitae low single to low double-digit percentage royalties on sales, subject to reduction in certain circumstances, as well as up to an aggregate of $70.0 million in potential one-time, sales-based milestone payments based on achievement of certain annual sales thresholds. The Company is solely responsible for the development and commercialization of the Menin Assets. Each party may terminate the Vitae License Agreement for the other party’s uncured material breach or insolvency, and the Company may terminate the Vitae License Agreement at any time upon advance written notice to Vitae. Vitae may terminate the Vitae License Agreement if the Company or any of its affiliates or sublicensees institutes a legal challenge to the validity, enforceability, or patentability of the licensed patent rights. Unless terminated earlier in accordance with its terms, the Vitae License Agreement will continue on a country-by-country and product-by-product basis until 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.

8

As of the date of the Vitae License Agreement, the asset acquired had no alternative future use nor had it reached a stage of technological feasibility. As the processes or activities that were acquired along with the license do not constitute a “business,” the transaction has been accounted for as an asset acquisition. As a result, in 2017, the upfront payment of $5.0 million was recorded as research and development expense in the consolidated statements of operations. Since the inception of the Vitae License Agreement, the Company achieved certain development and regulatory milestones re sulting in $38.0 million in expe nse, which includes an $18.0 million milestone expense in 2024 and a $12.0 million expense in 2025, related to the submission of a supplemental New Drug Application, or sNDA, for Revuforj and the first United States sale of Revuforj in its second indication.

UCB Biopharma Sprl

In 2016, the Company entered into a license agreement, or the UCB License Agreement, as amended from time to time, with UCB Biopharma Sprl, or UCB, under which UCB granted to the Company a worldwide, sublicensable, exclusive license to UCB6352, which the Company refers to as axatilimab, an anti-CSF-1R monoclonal antibody. Upon execution of the agreement, the Company agreed to pay UCB up to $119.5 million in one-time development and regulatory milestone payments over the term of the UCB License Agreement, subject to the achievement of certain milestone events. In the event that the Company or any of its affiliates or sublicensees commercializes axatilimab, the Company will also be obligated to pay UCB low double-digit percentage royalties on sales, subject to reduction in certain circumstances, as well as up to an aggregate of $250.0 million in potential one-time, sales-based milestone payments based on achievement of certain annual sales thresholds. Under certain circumstances, the Company may be required to share a percentage of non-royalty income from sublicensees, subject to certain deductions, with UCB. The Company is solely responsible for the development and commercialization of axatilimab, except that UCB was responsible for performing a limited set of transitional chemistry, manufacturing and control tasks related to axatilimab. Each party may terminate the UCB License Agreement for the other party’s uncured material breach or insolvency, and the Company may terminate the UCB License Agreement at any time upon advance written notice to UCB. UCB may terminate the UCB License Agreement if the Company or any of its affiliates or sublicensees institutes a legal challenge to the validity, enforceability, or patentability of the licensed patent rights. Unless terminated earlier in accordance with its terms, the UCB License Agreement will continue on a country-by-country and product-by-product basis until 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.

As of the date of the UCB License Agreement, the asset acquired had no alternative future use nor had it reached a stage of technological feasibility. As the processes or activities that were acquired along with the license do not constitute a “business,” the transaction has been accounted for as an asset acquisition. As a result, in 2016, the upfront payment of $5.0 million was recorded as research and development ex pense in the consolidated statements of operations. In connection with its most recent amendment of the UCB License Agreement, in the second quarter of 2022 the Company paid UCB $5.8 million, which was recognized as a milestone expense. Since the effective date of the license agreement, the Company achieved certain development and regulatory milestones and has recorded $41.0 million as research and development expense, which includes a $15.0 million milestone paid during the third quarter of 2024 upon the approval of Niktimvo and a $10.0 million milestone recognized in the first quarter of 2025 for the first patient dosed in a Phase III study with the compound in a combination with another agent. The Company also recognized a $10.0 million commercial milestone expense in the fourth quarter of 2025 upon the achievement of $150.0 million in net sales of Niktimvo.

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5. Net Loss per Share Attributable to Common Stockholders

Basic net loss per share attributable to common stockholders is computed by dividing the net loss attributable to common stockholders by the weighted-average number of common shares outstanding for the period. Because the Company has reported a net loss for all periods presented, diluted net loss per common share is the same as basic net loss per common share for those periods. The following table summarizes the computation of basic and diluted net loss per share attributable to common stockholders of the Company:

| Three Months Ended June 30, |  |  | Six Months Ended June 30, |
| 2026 |  |  | 2025 |  |  | 2026 |  |  | 2025 |
| (In thousands, except share and per share data) |  |  | (In thousands, except share and per share data) |
Numerator—basic and diluted: |  |  |  |  |  |  |  |  |  |  |
Net loss | $ | (49,363 | ) |  | $ | (71,847 | ) |  | $ | (92,036 | ) |  | $ | (156,693 | )
Net loss attributable to common stockholders—basic and diluted | $ | (49,363 | ) |  | $ | (71,847 | ) |  | $ | (92,036 | ) |  | $ | (156,693 | )
Net loss per share attributable to common stockholders—basic and diluted | $ | (0.55 | ) |  | $ | (0.83 | ) |  | $ | (1.04 | ) |  | $ | (1.82 | )
Denominator—basic and diluted: |  |  |  |  |  |  |  |  |  |  |
Weighted-average number of common shares used to compute net loss per share attributable to common stockholders—basic and diluted |  | 88,991,317 |  |  |  | 86,337,237 |  |  |  | 88,625,508 |  |  |  | 86,255,020 |

The following potentially dilutive securities have been excluded from the computation of diluted weighted-average shares outstanding because such securities have an antidilutive impact due to losses reported (in common stock equivalent shares):

|  | June 30, |
|  | 2026 |  |  | 2025 |
Options to purchase common stock |  |  | 13,389,854 |  |  |  | 13,933,003 |
Employee Stock Purchase Plan |  |  | 54,887 |  |  |  | 88,999 |
Non-vested restricted stock units (RSUs) |  |  | 3,348,409 |  |  |  | 2,577,678 |
Conversion of convertible notes |  |  | 10,097,350 |  |  |  | — |

For additional information related to the Company’s common stock see Note 14 — Stock Based Compensation.

6. Other Receivables, net

In April 2024, entinostat received marketing approval in China, and as a result, the Company recorded $3.5 million of milestone revenue in 2024. The Company had recorded a $3.7 million receivable re lated to milestones (plus accrued interest) under the license agreement with Eddingpharm in 2025, which remains outstanding as of June 30, 2026. As the receivable remains outstanding, and the Company has assessed the amount as non-recoverable, the Company recorded a full reserve against the asset as a selling, general and administrative expense in 2025.

The Company has recorded $2.7 million in receivables related to employee stock option exercises in which the cash payment was outstanding as of June 30, 2026.

7. Fair Value Measurements

The carrying amounts of cash and cash equivalents, restricted cash, accounts payable, and accrued expenses approximated their estimated fair values due to the short-term nature of these financial instruments. Fair value is defined as the exchange price that would be received for an asset or paid to transfer a liability (an exit price) 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 are performed in a manner to maximize the use of observable inputs and minimize the use of unobservable inputs. The accounting standard describes a fair value hierarchy based on three levels of inputs, of which the first two are considered observable and the last unobservable, that may be used to measure fair value, which are the following:

Level 1— Quoted prices (unadjusted) in active markets that are accessible at the market date for identical unrestricted assets or liabilities.

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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 for which all significant inputs are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities.

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 table below presents information about the Company’s assets and liabilities that are regularly measured and carried at fair value and indicate the level within the fair value hierarchy of valuation techniques the Company utilized to determine such fair values (in thousands):

|  | Fair Value Measurements Using |
|  |  |  |  | Quoted |  |  |  |  |  |  |
|  |  |  |  | Prices |  |  | Significant |  |  |  |
|  |  |  |  | (unadjusted) |  |  | Other |  |  | Significant |
|  | Total |  |  | in Active |  |  | Observable |  |  | Unobservable |
|  | Carrying |  |  | Markets |  |  | Inputs |  |  | Inputs |
|  | Value |  |  | (Level 1) |  |  | (Level 2) |  |  | (Level 3) |
|  | (In thousands) |
June 30, 2026 |  |  |  |  |  |  |  |  |  |  |  |
Assets: |  |  |  |  |  |  |  |  |  |  |  |
Cash and cash equivalents |  | $ | 336,477 |  |  | $ | 336,477 |  |  | $ | — |  |  | $ | — |
Short-term investments |  |  | 211,383 |  |  |  | — |  |  |  | 211,383 |  |  |  | — |
Long-term investments |  |  | 27,217 |  |  |  | — |  |  |  | 27,217 |  |  |  | — |
Total assets |  | $ | 575,077 |  |  | $ | 336,477 |  |  | $ | 238,600 |  |  | $ | — |
December 31, 2025 |  |  |  |  |  |  |  |  |  |  |  |
Assets: |  |  |  |  |  |  |  |  |  |  |  |
Cash and cash equivalents |  | $ | 115,358 |  |  | $ | 115,358 |  |  | $ | — |  |  | $ | — |
Short-term investments |  |  | 259,140 |  |  |  | — |  |  |  | 259,140 |  |  |  | — |
Long-term investments |  |  | — |  |  |  | — |  |  |  | — |  |  |  | — |
Total assets |  | $ | 374,498 |  |  | $ | 115,358 |  |  | $ | 259,140 |  |  | $ | — |

There have been no material impairments of our assets measured and carried at fair value during the periods ended June 30, 2026 and 2025. In addition, there have been no changes in valuation techniques during the periods ended June 30, 2026 and 2025. The fair value of Level 1 instruments classified as cash equivalents are valued using quoted market prices in active markets. The fair value of Level 2 instruments classified as short- and long-term investments are determined based on quoted prices in active markets, which are either directly or indirectly observable as of the reporting date with fair value being determined using models or other valuation methodologies.

The Company’s short and long-term investments are classified as available-for-sale securities. As of June 30, 2026, the remaining contractual maturities of the available-for-sale securities were 1 to 23 mon ths, and the balance in the Company’s accumulated other comprehensive loss was comprised solely of activity related to the Company’s available-for-sale securities. There were no realized gains or losses recognized on the sale or maturity of available-for-sale securities, during the three and six months ended June 30, 2026 and 2025. As a result, the Company did not reclassify any amounts out of accumulated other comprehensive gain for the same periods.

T he following table summarizes the available-for-sale securities:

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|  | Amortized |  |  | Unrealized |  |  | Unrealized |  |  |  |
|  | Cost |  |  | Gains |  |  | Losses |  |  | Fair Value |
|  | (In thousands) |
June 30, 2026 |  |  |  |  |  |  |  |  |  |  |  |
Commercial paper |  | $ | 84,572 |  |  | $ | — |  |  | $ | (100 | ) |  | $ | 84,471 |
Corporate bonds |  |  | 36,356 |  |  |  | — |  |  |  | (36 | ) |  |  | 36,319 |
US Treasury |  |  | 117,813 |  |  |  | — |  |  |  | (4 | ) |  |  | 117,810 |
|  | $ | 238,741 |  |  | $ | — |  |  | $ | (140 | ) |  | $ | 238,600 |
December 31, 2025 |  |  |  |  |  |  |  |  |  |  |  |
Commercial paper |  | $ | 86,066 |  |  | $ | 15 |  |  | $ | — |  |  | $ | 86,081 |
Corporate bonds |  |  | 28,227 |  |  |  | 30 |  |  |  | — |  |  |  | 28,257 |
US Treasury |  |  | 144,395 |  |  |  | 407 |  |  |  | — |  |  |  | 144,802 |
|  | $ | 258,688 |  |  | $ | 452 |  |  | $ | — |  |  | $ | 259,140 |

8. Prepaid Expenses and Other Current Assets

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

|  | June 30, 2026 |  |  | December 31, 2025 |
Prepaid insurance |  | $ | 1,841 |  |  | $ | 1,590 |
Interest receivable on investments |  |  | 2,656 |  |  |  | 2,146 |
Prepaid subscriptions |  |  | 1,900 |  |  |  | 2,221 |
Prepaid state and local taxes |  |  | — |  |  |  | 13 |
Prepaid rent |  |  | 54 |  |  |  | 55 |
Prepaid inventory |  |  | 8,605 |  |  |  | 6,252 |
Other |  |  | 2,424 |  |  |  | 1,219 |
Total prepaid expenses and other current assets |  | $ | 17,480 |  |  | $ | 13,496 |

9. Inv entory, net

Inventory, net consisted of the following (in thousands):

|  | June 30, 2026 |  |  | December 31, 2025 |
Raw materials |  | $ | 29,201 |  |  | $ | 29,027 |
Work-in-process |  |  | 2,434 |  |  |  | 2,112 |
Finished goods |  |  | 1,529 |  |  |  | 1,615 |
Total Inventory, net |  | $ | 33,164 |  |  | $ | 32,754 |

Inventories are stated at the lower of cost or net realizable value, as determined on a first-in, first-out basis.

Prior to the FDA's approval of Revuforj in November 2024, all costs for the manufacturing of product to support clinical development and commercial launch, including pre-launch inventory, were expensed as research and development costs. The pre-launch inventory will continue to be used in commercial production until it is depleted.

10. Property and Equipment, net

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

|  | June 30, |  |  | December 31, |
|  | 2026 |  |  | 2025 |
Equipment |  | $ | 311 |  |  | $ | 271 |
Leasehold improvements |  |  | 167 |  |  |  | 167 |
Furniture and fixtures |  |  | 134 |  |  |  | 134 |
Office and computer equipment |  |  | 34 |  |  |  | 34 |
Total property and equipment |  |  | 646 |  |  |  | 606 |
Accumulated depreciation |  |  | (434 | ) |  |  | (425 | )
Property and equipment, net |  | $ | 212 |  |  | $ | 181 |

Depreciation expense was $5,000 and $9,000 for the three and six months ended June 30, 2026. There was no depreciation expense for the three and six months ended June 30, 2025.

11. Accrued Expenses and Other Current Liabilities

Accrued expenses and other current liabilities consisted of the following (in thousands):

|  | June 30, 2026 |  |  | December 31, 2025 |
Product revenue allowances |  | $ | 11,115 |  |  | $ | 9,810 |
Accrued clinical study and trial costs |  |  | 20,878 |  |  |  | 18,977 |
Accrued selling, general, and administrative costs |  |  | 6,483 |  |  |  | 6,316 |
Accrued compensation and related costs |  |  | 11,384 |  |  |  | 24,352 |
Accrued milestone costs |  |  | — |  |  |  | 10,000 |
Accrued royalty payable |  |  | 8,183 |  |  |  | 7,372 |
Accrued interest - royalty interest financing |  |  | 34,149 |  |  |  | 25,516 |
Accrued interest - convertible note |  |  | 555 |  |  |  | — |
Other |  |  | 1,550 |  |  |  | 721 |
Total accrued expenses and other current liabilities |  | $ | 94,297 |  |  | $ | 103,064 |

12. Royalty Interest Financing Liability

On November 4, 2024, the Company entered into a Purchase and Sale Agreement, or the Purchase and Sale Agreement, with Royalty Pharma Development Funding, LLC, or Royalty Pharma, pursuant to which Royalty Pharma purchased rights to certain revenue streams from net sales of products comprising or containing axatilimab (including Niktimvo™) by the Company, its affiliates and its licensees in the United States and its respective territories, districts, commonwealths and possessions (including Guam and Puerto Rico) in exchange for an upfront fee of $350 million.

Pursuant to the Purchase and Sale Agreement, Royalty Pharma purchased the right to receive a percentage of net sales equal to a royalty rate of 13.8% on quarterly net sales of Niktimvo in the United States and its respective territories; provided that the royalty rate is subject to certain adjustments based on future aggregate net sales of the product in the United States and its respective territories, or the Revenue Participation Right. Aggregate payments made to Royalty Pharma in respect of the Revenue Participation Right will be capped at $822.5 million, or the Royalty Cap.

The Purchase and Sale Agreement contains customary representations, warranties and indemnities of the Company and Royalty Pharma and customary covenants relating to the royalty payments, including the grant of a back-up security interest in the purchased royalties and certain assets related to the product and restrictions on the incurrence of additional indebtedness and on the existence of liens on the Company’s assets related to the product.

Upon a change of control, the Company will have the right, but not the obligation, to repurchase the Revenue Participation Right at a repurchase price set forth in the Purchase and Sale Agreement. In addition, the Purchase and Sale Agreement provides that if certain events of default occur, including certain bankruptcy events or certain termination events with respect to the Company’s license agreement with UCB Biopharma Srl, Royalty Pharma may require the Company to repurchase Royalty Pharma’s interests in the Revenue Participation Right at a repurchase price equal to the Royalty Cap.

The Company assessed the Purchase and Sale Agreement and identified it as a sale of future revenue in the form of a debt instrument to be accounted for as a liability under Topic ASC 470, Borrower’s Accounting for Debt Modifications. The Company has elected to use the prospective method in its calculation of its effective interest rate and will update this calculation quarterly when there are changes in the projected sales. Issuance costs pursuant to the Purchase and Sale Agreement consisted primarily of bank and

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legal fees and totaled $6.3 million. These issuance costs were recorded as a direct deduction to the carrying amount of the liability and will be amortized under the effective interest method over the estimated period the liability will be repaid. For the period ended June 30, 2026, the Company estimated an effective annual interest rate of approxim ately 13.02%. Ove r the course of the Purchase and Sale Agreement, the annual interest rate will be affected by the amount and timing of net Niktimvo revenue recognized and change in timing of forecasted net Niktimvo revenue. On a quarterly basis, the Company reassesses the expected timing of the net Niktimvo revenue, recalculates the amortization and effective interest rate, and adjusts the accounting prospectively, as needed. For the three and six months ended June 30, 2026, the Company recognized royalty interest expe nse of $12.1 million and $24.0 million, respectively. The Company made $15.3 million of paym ents pursuant to the Purchase and Sale Agreement during the six month period ended June 30, 2026.

|  | June 30, 2026 |  |  | December 31, 2025 |
Current portion of royalty interest financing liability |  | $ | — |  |  | $ | — |
Royalty interest financing liability, less current portion |  |  | 350,000 |  |  |  | 350,000 |
Debt issuance costs |  |  | (5,974 | ) |  |  | (6,091 | )
Total royalty interest financing liability, net |  | $ | 344,026 |  |  | $ | 343,909 |

13. Convertible Notes

In June 2026, the Company issued $250.0 million aggregate principal amount of 2.25% Convertible Senior Notes due 2031, or the 2031 Notes, in a private placement to institutional accredited investors that are qualified institutional buyers under Rule 144A in reliance on the exemption from registration provided by Section 4(a)(2) of the Securities Act. The 2031 Notes are senior, unsecured obligations of the Company and bear interest at 2.25% per annum, payable semi-annually in arrears on June 15 and December 15, beginning December 15, 2026. The 2031 Notes mature on June 15, 2031, unless earlier converted, redeemed, or repurchased. The initial conversion rate is 40.3894 shares of common stock per $1,000 principal amount (equivalent to an initial conversion price of approximately $24.76 per share), subject to customary anti-dilution adjustments under certain circumstances in accordance with the terms of the indenture relating to the 2031 Notes. Upon conversion, the Company will pay or deliver, at its election, cash, shares of its common stock, or a combination of cash and shares of common stock. Before March 15, 2031, the 2031 Notes are convertible only upon the satisfaction of specified conditions; thereafter, the 2031 Notes are convertible at any time until the second scheduled trading day before maturity. The Company may redeem for cash all or any portion of the 2031 Notes (subject to certain limitations) on or after June 20, 2029 if the last reported sale price of its common stock exceeds 130% of the conversion price for a specified period at a redemption price equal to 100% of the principal amount of the 2031 Notes to be redeemed, plus accrued and unpaid interest to, but excluding, the redemption date. If the Company undergoes a fundamental change (as defined in the indenture governing the 2031 Notes), holders may require the Company to repurchase their 2031 Notes for cash at a price equal to 100% of the principal amount plus accrued and unpaid interest to, but excluding, the fundamental change repurchase date. Initially, a maximum of 13,631,400 shares of common stock may be issued upon conversion of the 2031 Notes based on the initial maximum conversion rate of 54.5256 shares of common stock per $1,000 principal amount of 2031 Notes, which is subject to customary anti-dilution adjustment provisions. The 2031 Notes are classified as a long-term liability under ASC 470 and are presented net of unamortized debt issuance costs, which are amortized to interest expense over the term of the 2031 Notes using the effective interest method. Accrued interest related to the 2031 Notes is recorded under the accrued expenses and other current liabilities line of the balance sheet. As of June 30, 2026, the net carrying amount of the 2031 Notes was $244.1 million, unamortized debt issuance costs were $5.9 million, and the effective interest rate was 2.733%.

|  | June 30, 2026 |
Current portion of convertible note liability |  | $ | — |
Convertible note liability, less current portion |  |  | 250,000 |
Debt issuance costs |  |  | (5,910 | )
Total convertible note liability, net |  | $ | 244,090 |

14. Stock-Based Compensation

In January 2026, the number of shares of common stock available for issuance under the Company’s 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. In June 2026, the 2026 Equity Incentive Plan, or 2026 Plan, was approved. The maximum number of shares of the Company’s common stock that may be issued under the 2026 Plan is 17,134,916 shares, which is the sum of (i) 7,200,000 newly authorized shares, plus (ii) up to 9,934,916 shares of common stock

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subject to outstanding stock awards granted under the 2015 Plan that, on or after the 2026 Plan becomes effective, expire or otherwise terminate prior to exercise or settlement.

As of June 30, 2026, there were 424,326 shares of common stock available for issuance under the 2023 Plan and 7,448,808 shares of common stock available for issuance under the 2026 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 Company’s 2015 Employee Stock Purchase Plan, or ESPP, in the consolidated statements of comprehensive loss as follows:

| Three Months Ended June 30, |  |  | Six Months Ended June 30, |
| 2026 |  |  | 2025 |  |  | 2026 |  |  | 2025 |
Research and development | $ | 4,510 |  |  | $ | 4,196 |  |  | $ | 8,537 |  |  | $ | 7,864 |
Selling, general and administrative |  | 9,504 |  |  |  | 9,591 |  |  |  | 17,530 |  |  |  | 16,303 |
Total | $ | 14,014 |  |  | $ | 13,787 |  |  | $ | 26,067 |  |  | $ | 24,167 |

Compensation expense by type of award in the three and six months ended June 30, 2026 and 2025 was as follows:

| Three Months Ended June 30, |  |  | Six Months Ended June 30, |
| 2026 |  |  | 2025 |  |  | 2026 |  |  | 2025 |
Stock options | $ | 8,178 |  |  | $ | 8,707 |  |  | $ | 15,739 |  |  | $ | 16,392 |
RSUs |  | 5,624 |  |  |  | 4,757 |  |  |  | 9,905 |  |  |  | 7,332 |
ESPP |  | 212 |  |  |  | 323 |  |  |  | 423 |  |  |  | 443 |
Total | $ | 14,014 |  |  | $ | 13,787 |  |  | $ | 26,067 |  |  | $ | 24,167 |

In addition, stock-based compensation exp ense of $0.1 million and $0.2 million was ca pitalized to inventory for the three and six months ended June 30, 2026, respectively, which represents the stock-based compensation expense incurred related to employees involved in the manufacturing process of finished goods and samples. For the three and six months ended June 30, 2025, $0.1 million and $0.2 million of stock compensation expense was capitalized to inventory.

As of June 30, 2026, there were $103.4 million of unrecognized compensation costs related to employee and non-employee unvested stock options and RSUs granted under the Inducement Plan, 2015 Plan, 2026 Plan, and the Company’s 2007 Stock Plan, which are expected to be recognized over a weighted-average remaining service period of 2.67 years.

Employee Benefit Plan

The Company maintains a defined contribution 401(k) retirement plan. For the three and six months ended June 30, 2026, the Company made $0.3 million and $2.8 million, respectively, of contributions to t he plan. For the three and six months ended June 30, 2025, the Company made $0.3 million and $2.6 million, respectively, of contributions to the plan. The Company’s contributions were made in cash.

15. 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 June 30, 2026, 285,714 pre-funded warrants were issued and outstanding.

16. 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

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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 June 30, 2026.

17. 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 Company’s Chief Operating Decision Maker, or CODM, Michael Metzger, uses consolidated net loss as the segment’s 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 June 30, |  |  | Six Months Ended June 30, |
|  | 2026 |  |  | 2025 |  |  | 2026 |  |  | 2025 |
June 30, 2026 |  |  |  |  |  |  |  |  |  |  |  |
Total Revenue |  | $ | 72,788 |  |  | $ | 37,958 |  |  | $ | 137,652 |  |  | $ | 57,753 |
Less: Significant and other segment expenses |  |  |  |  |  |  |  |  |  |  |  |
Cost of product sales |  |  | 3,208 |  |  |  | 1,279 |  |  |  | 5,841 |  |  |  | 2,164 |
Research and development expenses |  |  |  |  |  |  |  |  |  |  |  |
Revumenib-related costs |  |  | 35,493 |  |  |  | 28,155 |  |  |  | 61,218 |  |  |  | 48,960 |
Axatilimab-related costs |  |  | 8,682 |  |  |  | 9,053 |  |  |  | 18,315 |  |  |  | 28,764 |
Other R&D programs |  |  | 1,043 |  |  |  | 1,826 |  |  |  | 1,205 |  |  |  | 2,747 |
Personnel cost and other expenses |  |  | 18,308 |  |  |  | 18,997 |  |  |  | 37,606 |  |  |  | 35,528 |
General and administrative expenses |  |  |  |  |  |  |  |  |  |  |  |
Commercial-related expenses |  |  | 9,869 |  |  |  | 9,914 |  |  |  | 17,590 |  |  |  | 20,739 |
Personnel cost and other expenses |  |  | 16,298 |  |  |  | 19,307 |  |  |  | 32,999 |  |  |  | 38,389 |
Other SG&A expenses |  |  | 5,868 |  |  |  | 4,993 |  |  |  | 11,008 |  |  |  | 9,405 |
Stock-based compensation |  |  | 14,014 |  |  |  | 13,787 |  |  |  | 26,067 |  |  |  | 24,167 |
Royalty interest expense |  |  | 12,119 |  |  |  | 7,854 |  |  |  | 23,965 |  |  |  | 15,903 |
Convertible note interest expense |  |  | 555 |  |  |  | — |  |  |  | 555 |  |  |  | — |
Interest expense (income), net |  |  | (3,744 | ) |  |  | (5,946 | ) |  |  | (7,305 | ) |  |  | (13,127 | )
Other expense, net |  |  | 438 |  |  |  | 586 |  |  |  | 624 |  |  |  | 807 |
Segment net loss |  | $ | (49,363 | ) |  | $ | (71,847 | ) |  | $ | (92,036 | ) |  | $ | (156,693 | )

16

Item 2. Management’s Discussion and Analysis of Financial Condition and Results of Operations

The following information should be read in conjunction with the unaudited financial information and the notes thereto included in this Quarterly Report on Form 10-Q, or the Quarterly Report, and the audited financial information and the notes thereto included in our Annual Report on Form 10-K that was filed with the Securities and Exchange Commission, or SEC, on February 26, 2026.

Company Overview

We are a commercial-stage biopharmaceutical company advancing innovative cancer therapies. We currently have two commercially approved medicines, Revuforj® (revumenib) and Niktimvo™ (axatilimab-csfr), and a robust pipeline of late- and early-stage development programs.

Revuforj is our first-in-class menin inhibitor that was approved by the U.S. Food and Drug Administration, or FDA, in November 2024 for the treatment of relapsed or refractory, or R/R, acute leukemia with a lysine methyltransferase 2A gene, or KMT2A, translocation in adult and pediatric patients one year and older. In October 2025, Revuforj received a second approval from the FDA for the treatment of R/R acute myeloid leukemia, or AML, with a susceptible nucleophosmin 1 mutation, or NPM1m, in adult and pediatric patients one year and older who have no satisfactory alternative treatment options. We are also studying revumenib in combination with standard-of-care agents in NPM1m AML or KMT2A-rearranged, or KMT2Ar, acute leukemia across the treatment landscape, including in newly diagnosed patients.

Niktimvo is our first-in-class colony stimulating factor-1 receptor, or CSF-1R, blocking antibody that was approved by the FDA in August 2024 for the treatment of chronic graft-versus-host disease, or cGVHD, after failure of at least two prior lines of systemic therapy in adult and pediatric patients weighing at least 40 kg. Axatilimab is in development for the treatment of newly diagnosed cGVHD patients in combination with standard-of-care therapies, and for the treatment of idiopathic pulmonary fibrosis, or IPF.

We licensed the global rights to revumenib and axatilimab, the first two FDA approved medicines to emerge from our pipeline. We are leading the commercialization and further development of revumenib and working closely with our collaboration partner, Incyte, on the commercialization and further development of axatilimab. We plan to continue to leverage the technical and business expertise of our management team and scientific collaborators to license, acquire and develop additional therapeutics to expand our pipeline.

In July 2026, we announced two new pipeline assets, SNDX-4321 and SNDX-62122. SNDX-4321 is a novel, mutant-selective, allosteric epidermal growth factor receptor, or EGFR, inhibitor designed to address non-small cell lung cancer, or NSCLC, patient populations with significant unmet needs. The Company has an exclusive worldwide license to develop and commercialize SNDX-4321. SNDX-62122 is a next-generation menin inhibitor in development for myelofibrosis, or MF. SNDX-62122 is the first molecule from our library of internally developed and wholly owned next-generation menin inhibitors that we intend to advance into new areas. Our SNDX-62122 program builds off recently published revumenib preclinical data showing that menin is a novel dependency in proliferative megakaryocytes, major drivers of MF. We expect the development of SNDX-62122 to be informed and de-risked by a planned Phase 1/2 proof-of-principle trial of revumenib in MF.

We have incurred significant operating losses since our inception. While we generate product revenue from sales of Revuforj and collaboration as well as milestone revenue from sales of Niktimvo, we continue to incur significant research and development and other expenses related to our ongoing operations. Except for 2021, we have not been profitable and have incurred losses in each period since our inception in 2005. For the six months ended June 30, 2026 and 2025, we reported a net loss of $92.0 million and $156.7 million, respectively. As of June 30, 2026, we had an accumulated deficit of $1.6 billion. As of June 30, 2026, we had cash, cash equivalents and short- and long-term investments of $575.1 million.

Recent Business Highlights

Revuforj®(revumenib)

•
Achieved $54.7 million in Revuforj net revenue in the second quarter of 2026, a 91% increase over the second quarter of 2025 and a 12% increase over the first quarter of 2026. Total prescriptions were approximately 1,500 in the second quarter of 2026, an approximate 121% increase over the second quarter of 2025 and a 15% increase over the first quarter of 2026. The net revenue and prescription growth reflects an increasing average treatment duration, primarily driven by a growing pool of patients receiving Revuforj for an extended period in the post-transplant setting.
•
Advanced our scientific leadership in menin inhibition with the presentation of 16 revumenib abstracts at the 2026 American Society of Clinical Oncology, or ASCO, and the European Hematology Association, or EHA, annual meetings in June 2026. The data presented span multiple acute leukemia subtypes and settings, including frontline and post-transplant maintenance.

17

•
Published data from the Phase 1/2 SAVE trial of an all-oral combination of revumenib, decitabine/cedazuridine, and venetoclax in R/R NPM1m, KMT2Ar, and NUP98r AML in the Journal of Clinical Oncology in June 2026. The results showed deep and durable remissions in a heavily pretreated patient population. The overall response rate was 88% (37/42), composite complete remission, or CRc, rate was 71% (30/42), and complete remission plus complete remission with partial hematologic recovery rate was 60% (25/42). 80% of evaluable CRc responders were measurable residual disease, or MRD, negative. 45% (19/42) of patients proceeded to a transplant and 63% (12/19) resumed revumenib post-transplant.
•
Published preclinical revumenib data showing that menin is a novel dependency in proliferative megakaryocytes, major drivers of MF, in Cancer Cell in July 2026. These data provide the basis for our plans to develop SNDX-62122, an internally developed, next-generation menin inhibitor, for MF.
•
We expect to have a major presence at upcoming medical meetings in the second half of 2026 with the presentation of new/updated revumenib data including:
•
Real-world evidence from multiple centers
•
Post-transplant maintenance data
•
Frontline data from the BEAT AML trial of revumenib in combination with venetoclax/azacitidine in NPM1m and KMT2Ar AML.
•
Frontline data from the Phase 1/2 SAVE trial of an all-oral combination of revumenib, decitabine/cedazuridine, and venetoclax in NPM1m, KMT2Ar, or NUP98r AML.
•
Frontline data from the Phase 1 trial of revumenib in combination with intensive chemotherapy in NPM1m, KMT2Ar, or NUP98r AML.
•
Multiple clinical trials evaluating revumenib across the acute leukemia treatment continuum are ongoing, such as:
•
EVOLVE-2: A pivotal, Phase 3, randomized, double-blind, placebo-controlled trial of revumenib in combination with venetoclax and azacitidine in newly diagnosed NPM1m (primary efficacy analysis population) and KMT2Ar AML patients who are unfit for intensive chemotherapy. The trial is being conducted in collaboration with the HOVON network, a leading cooperative clinical trial group with extensive experience studying novel therapies for hematologic malignancies.
•
REVEAL-ND: A pivotal, Phase 3, randomized, double-blind, placebo-controlled trial of revumenib in combination with intensive chemotherapy in newly diagnosed NPM1m AML patients.
•
SAVE: A Phase 1/2 trial evaluating an all-oral combination of revumenib with venetoclax and decitabine/cedazuridine in pediatric and adult patients with newly diagnosed and R/R AML or mixed-lineage acute leukemia harboring either NPM1m, KMT2Ar, or NUP98r alterations. The trial is being conducted by investigators from MD Anderson Cancer Center.
•
Intensive chemotherapy: Two ongoing Phase 1 trials evaluating the combination of revumenib with intensive chemotherapy (7+3) in newly diagnosed NPM1m or KMT2Ar acute leukemia patients.
•
BEAT AML: A Phase 1 trial evaluating the combination of revumenib with venetoclax and azacitidine in newly diagnosed older adults (≥60 years) with NPM1m or KMT2Ar AML. The trial is being conducted as part of the Leukemia & Lymphoma Society's Beat AML® Master Clinical Trial.
•
Post-transplant maintenance: A Phase 1 trial evaluating the safety and preliminary efficacy of revumenib as post-transplant maintenance in patients with KMT2Ar or NPM1m acute leukemia. The trial is being conducted by investigators from the City of Hope Medical Center.
•
Break Through Cancer: A Phase 2 trial studying whether the combination of revumenib and venetoclax can eliminate MRD in patients with AML and extend progression-free survival. The trial is being conducted by Break Through Cancer, a collaboration between leading U.S. cancer research centers.

18

•
INTERCEPT: A Phase 1 trial evaluating the use of novel therapies, including revumenib, to target MRD and early relapse in AML. The trial is being conducted by the Australasian Leukaemia and Lymphoma Group as part of the INTERCEPT AML master clinical trial.
•
We expect the RAVEN trial to initiate in the second half of 2026. RAVEN is a Phase 2 collaborative trial of revumenib in combination with venetoclax and azacitidine in newly diagnosed KMT2Ar patients who would be considered eligible, or fit, for intensive chemotherapy.
•
We expect the MenTain Phase 2 trial to initiate around the end of 2026. MenTain will be the first randomized, placebo-controlled trial specifically focused on evaluating revumenib as post-transplant maintenance.
•
We expect to publish safety and efficacy data from R/R NUP98r acute leukemia patients treated with revumenib in the fourth quarter of 2026.

Niktimvo™ (axatilimab-csfr)

•
Achieved $60.3 million in Niktimvo net revenue in the second quarter of 2026, a 67% increase over the second quarter of 2025 and a 9% increase over the first quarter of 2026. Syndax and Incyte are co-commercializing Niktimvo. Syndax records 50% of the Niktimvo net commercial profit, defined as net product revenue minus the cost of sales and commercial expenses. Syndax’s share of the Niktimvo product contribution, reported as collaboration revenue, was $18.1 million in the second quarter of 2026.
•
Two trials evaluating axatilimab in combination with standard of care therapies in newly diagnosed chronic GVHD patients are ongoing, including:
•
A Phase 2, open-label, randomized, multicenter trial of axatilimab in combination with ruxolitinib in patients ≥ 12 years of age with newly diagnosed chronic GVHD. We anticipate topline data in the fourth quarter of 2026.
•
A pivotal Phase 3, randomized, double-blind, placebo-controlled, multicenter trial of axatilimab in combination with corticosteroids in patients ≥ 12 years of age with newly diagnosed chronic GVHD. We anticipate topline data in early 2028.
•
We anticipate topline data from MAXPIRe, a Phase 2, 26-week randomized, double-blinded, placebo-controlled trial of axatilimab on top of standard of care in patients with IPF in the fourth quarter of 2026.

Pipeline Assets

SNDX-4321

•
In July 2026, we announced the expansion of our pipeline with SNDX-4321, a mutant-selective, CNS-penetrant, allosteric EGFR inhibitor. SNDX-4321 is in development for NSCLC patient populations with significant unmet needs, such as those with L858R mutations, CNS metastases, atypical activating mutations, or acquired resistance to current therapies. In contrast to ATP-site directed third and fourth generation EGFR inhibitors, SNDX-4321 is a novel allosteric inhibitor which binds at a pocket adjacent to the ATP site that is only accessible in the presence of L858R and certain other EGFR mutations.
•
We expect to submit an investigational new drug (IND) application for SNDX-4321 by the end of 2026 and to initiate a Phase 1 trial in EGFRm NSCLC in 2027.

SNDX-62122

•
In July 2026, we announced the selection of SNDX-62122, a next-generation menin inhibitor, for development in MF. SNDX-62122 is the first candidate from a library of internally developed, wholly owned next-generation menin inhibitors that we intend to advance into new areas.
•
We expect to submit an IND and initiate a Phase 1 trial of SNDX-62122 in MF in 2027. The development of SNDX-62122 will be informed by a Phase 1/2 proof-of-principle trial of revumenib in MF that is expected to initiate in the fourth quarter of 2026 with initial clinical data expected in the second half of 2027.

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Financial Operations Overview

Product Revenue, net

Our FDA-approved product, Revuforj, was approved by the FDA for commercial sale in the U.S. on November 15, 2024. In accordance with GAAP, we determine net product revenue for Revuforj, with specific assumptions for variable consideration components including, but not limited to, trade discounts and allowances, co-pay assistance programs and payor rebates. We record product revenue net of estimated discounts, chargebacks, rebates, product returns, and other gross-to-net revenue deductions.

Collaboration revenue, net

In September 2021, we entered into the Incyte License and Collaboration Agreement, or the Incyte License, with Incyte covering the worldwide development and commercialization of axatilimab. In August 2024, the FDA approved Niktimvo for the treatment of cGVHD after failure of at least two prior lines of systemic therapy in adult and pediatric patients weighing at least 40 kg (88.2 lbs).

In accordance with Topic ASC 808, Collaboration Arrangements, Incyte has been identified as the principal in product sales, therefore, we will recognize its 50% share of any profits or losses in the amount of net product sales less cost of goods sold and shared commercial and other expenses, in the period in which the underlying sales and costs are recognized. Our share of net profits in connection with commercialization of Niktimvo will be presented as “Collaboration revenue, net” and our share of net losses will be presented as “Collaboration loss, net” within operating expenses. Collaboration revenue or expense is made up of our share of the 50% profit with Incyte. We record collaboration revenue net of commercial expenses, including any royalties owed on license agreements. We will continue to recognize the costs associated with ongoing development services in the R&D operating expense line, including any cost-sharing components with Incyte.

Cost of Product Sales

Our cost of product sales includes the cost of goods sold for Revuforj and license agreement royalties associated with its sales in the United States. Until we received regulatory approval for Revuforj in the United States in November 2024, we recorded expenses incurred for the manufacturing of pre-launch inventory that would support a U.S. launch as research and development expense. Accordingly, the cost of goods sold for a Revuforj may not include the full cost of manufacturing until the initial pre-launch, and previously expensed, inventory is depleted.

Research and Development

Since our inception, we have primarily focused on our clinical development programs. Research and development expenses consist primarily of costs incurred for the development of our products and product candidates and include:

•
expenses incurred under agreements related to our clinical trials, including the costs for investigative sites and contract research organizations, or CROs, that conduct our clinical trials;
•
employee-related expenses associated with our research and development activities, including salaries, benefits, travel and non-cash stock-based compensation expenses;
•
manufacturing process-development, clinical supplies and technology-transfer expenses;
•
license fees and milestone payments under our license agreements;
•
consulting fees paid to third parties;
•
allocated facilities and overhead expenses; and
•
costs associated with regulatory operations and regulatory compliance requirements.

20

Internal and external research and development costs are expensed as they are incurred. Cost-sharing amounts received by us are recorded as reductions to research and development expense. Costs for certain development activities, such as clinical trials, are recognized based on an evaluation of the progress to completion of specific tasks using data such as patient enrollment, clinical site activations or other information provided to us by our vendors.

Research and development activities are central to our business model. Product candidates in late stages of clinical development generally have higher development costs than those in earlier stages of clinical development, primarily due to the increased size and duration of late-stage clinical trials. We plan to continue to spend a significant amount of our resources on research and development activities for the foreseeable future as we continue to advance the development of our products and product candidates. The amount of research and development expenses allocated to external spending will continue to grow, while we expect our internal spending to grow at a slower and more controlled pace.

It is difficult to determine, with certainty, the duration and completion costs of our current or future preclinical programs, research studies and clinical trials of our product candidates. The duration, costs and timing of research studies and clinical trials of our products and product candidates will depend on a variety of factors that include, but are not limited to, the following:

•
per patient costs;
•
the number of patients that participate;
•
the number of clinical trial sites;
•
the countries in which the trials are conducted;
•
the length of time required to enroll eligible patients;
•
the potential additional safety monitoring or other studies requested by regulatory agencies;
•
the duration of patient monitoring;
•
the efficacy and safety profile of the product candidates; and
•
timing and receipt of any regulatory approvals.

In addition, the probability of success for each product candidate will depend on numerous factors, including competition, manufacturing capability and commercial viability. The successful development of our products and additional product candidates is highly uncertain. At this time, we cannot reasonably estimate the nature, timing or costs of the efforts that will be necessary to complete the remainder of the development of our products and additional product candidates for the period, if any, in which material net cash inflows from these potential product candidates may commence. Clinical development timelines, the probability of success and development costs can differ materially from expectations.

Selling, General and Administrative

Selling, general and administrative expenses consist primarily of employee-related expenses, including salaries, benefits, non-cash stock-based compensation and travel expenses, for our employees in executive, finance, human resources, business development and support functions, as well as sales and marketing expenses to support the launch and commercialization of Revuforj and Niktimvo. Other selling, general and administrative expenses include facility-related costs not otherwise allocated to research and development expenses and accounting, tax, legal, information technology and consulting services.

Royalty Interest Expense

Royalty interest expense consists of the interest recorded related to the Royalty Pharma Purchase and Sale Agreement under the effective interest method.

Convertible Note Interest Expense

Convertible note interest expense consists of the interest recorded related to the convertible note liability under the effective interest method.

Interest Expense

Interest expense consists primarily of expense related to the interest recognized for capital leases.

Interest Income

Interest income consists of income earned on our cash, cash equivalents and short- and long-term investment balances.

21

Other (Expense) Income, net

Other (expense) income, net consists of the revaluation of foreign currency related to trade payables.

Recent Accounting Pronouncements

For a discussion of new accounting pronouncements please read Note 3 - Summary of Significant Accounting Policies to our unaudited consolidated financial statements included in this Quarterly Report.

Critical Accounting Policies and Estimates

Our management’s discussion and analysis of financial condition and results of operations are based on our financial statements, which have been prepared in accordance with accounting principles generally accepted in the United States, or U.S. GAAP. The preparation of these financial statements requires us to make estimates, judgments and assumptions that may affect the reported amounts of assets, liabilities, equity, revenue and expenses and related disclosures of contingent assets and liabilities. We base our estimates on historical experience, known trends and events and various other factors that are 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 that are not readily apparent from other sources. Actual results may differ from these estimates under different assumptions or conditions. In making estimates and judgments, management employs critical accounting policies.

There have been no material changes to our critical accounting estimates described in the “Management’s Discussion and Analysis of Financial Condition and Results of Operations” contained in our Annual Report on Form 10-K for the fiscal year ended December 31, 2025.

Results of Operations

Comparison of the three and six months ended June 30, 2026 and 2025:

|  | Three Months Ended June 30, |  |  | Change |  |  | Six Months Ended June 30, |  |  | Change |
|  | 2026 |  |  | 2025 |  |  | $ |  |  | 2026 |  |  | 2025 |  |  | $ |
|  | (In thousands) |  |  | (In thousands) |
Revenue: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Product revenue, net |  | $ | 54,700 |  |  | $ | 28,600 |  |  | $ | 26,100 |  |  | $ | 103,623 |  |  | $ | 48,642 |  |  |  | 54,981 |
Collaboration revenue, net |  |  | 18,088 |  |  |  | 9,358 |  |  |  | 8,730 |  |  |  | 34,029 |  |  |  | 9,111 |  |  |  | 24,918 |
Total revenues |  |  | 72,788 |  |  |  | 37,958 |  |  |  | 34,830 |  |  |  | 137,652 |  |  |  | 57,753 |  |  |  | 79,899 |
Operating expenses: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Cost of goods sold |  | $ | 3,208 |  |  | $ | 1,279 |  |  | $ | 1,929 |  |  | $ | 5,841 |  |  | $ | 2,164 |  |  |  | 3,677 |
Research and development |  |  | 68,036 |  |  |  | 62,227 |  |  |  | 5,809 |  |  |  | 126,881 |  |  |  | 123,863 |  |  |  | 3,018 |
Selling, general and administrative |  |  | 41,539 |  |  |  | 43,805 |  |  |  | (2,266 | ) |  |  | 79,127 |  |  |  | 84,836 |  |  |  | (5,709 | )
Total operating expenses |  |  | 112,783 |  |  |  | 107,311 |  |  |  | 5,472 |  |  |  | 211,849 |  |  |  | 210,863 |  |  |  | 986 |
Loss from operations |  |  | (39,995 | ) |  |  | (69,353 | ) |  |  | (29,358 | ) |  |  | (74,197 | ) |  |  | (153,110 | ) |  |  | (78,913 | )
Other (expense) income, net: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Royalty interest expense |  |  | (12,119 | ) |  |  | (7,854 | ) |  |  | (4,265 | ) |  |  | (23,965 | ) |  |  | (15,903 | ) |  |  | (8,062 | )
Convertible note interest expense |  |  | (555 | ) |  |  | — |  |  |  | (555 | ) |  |  | (555 | ) |  |  | — |  |  |  | (555 | )
Other interest expense |  |  | (2 | ) |  |  | (4 | ) |  |  | 2 |  |  |  | (2 | ) |  |  | (6 | ) |  |  | 4 |
Interest income |  |  | 3,746 |  |  |  | 5,950 |  |  |  | (2,204 | ) |  |  | 7,307 |  |  |  | 13,133 |  |  |  | (5,826 | )
Other expense |  |  | (438 | ) |  |  | (586 | ) |  |  | 148 |  |  |  | (624 | ) |  |  | (807 | ) |  |  | 183 |
Total other (expense) income, net |  |  | (9,368 | ) |  |  | (2,494 | ) |  |  | (6,874 | ) |  |  | (17,839 | ) |  |  | (3,583 | ) |  |  | (14,256 | )
Net loss |  | $ | (49,363 | ) |  | $ | (71,847 | ) |  | $ | (22,484 | ) |  | $ | (92,036 | ) |  | $ | (156,693 | ) |  | $ | (64,657 | )

Product Revenue, net

In November 2024, we began to generate product revenue from sales of Revuforj in the United States. Product revenue, net from sales of Revuforj for the three and six months ended June 30, 2026, was $54.7 million and $103.6 million, respectively. The increase in product revenue from the comparable prior period end was due to increased sales volume as a result of increased brand awareness.

Collaboration Revenue, net

22

Collaboration revenue, net, representing our share of net profits in connection with commercialization of Niktimvo, for the three and six months ended June 30, 2026, was $18.1 million and $34.0 million, respectively. The increase in collaboration revenue from the comparable prior period end was due to increased sales volume as a result of increased brand awareness.

Cost of Product Sales

Our cost of product sales increased by $1.9 million from the comparable prior year period due to increased product sales of Revuforj. Included in cost of product sales are royalties owed to AbbVie on Revuforj sales as part of the Vitae License Agreement.

Research and Development

The following table summarizes the research and development expenses for the three and six months ended June 30, 2026 and 2025:

|  | Three Months Ended June 30, |  |  | Change |  |  | Six Months Ended June 30, |  |  | Change |
|  | 2026 |  |  | 2025 |  |  | $ |  |  | 2026 |  |  | 2025 |  |  | $ |
|  | (In thousands) |  |  | (In thousands) |
Revumenib-related costs |  | $ | 35,493 |  |  | $ | 28,156 |  |  | $ | 7,337 |  |  | $ | 61,218 |  |  | $ | 48,960 |  |  | $ | 12,258 |
Axatilimab-related costs |  |  | 8,682 |  |  |  | 9,053 |  |  |  | (371 | ) |  |  | 18,315 |  |  |  | 28,764 |  |  |  | (10,449 | )
Other research and development programs |  |  | 1,043 |  |  |  | 1,789 |  |  |  | (746 | ) |  |  | 1,205 |  |  |  | 2,747 |  |  |  | (1,542 | )
Personnel cost and other expenses |  |  | 18,308 |  |  |  | 19,033 |  |  |  | (725 | ) |  |  | 37,606 |  |  |  | 35,528 |  |  |  | 2,078 |
Stock-based compensation |  |  | 4,510 |  |  |  | 4,196 |  |  |  | 314 |  |  |  | 8,537 |  |  |  | 7,864 |  |  |  | 673 |
Total research and development expenses |  | $ | 68,036 |  |  | $ | 62,227 |  |  | $ | 5,809 |  |  | $ | 126,881 |  |  | $ | 123,863 |  |  | $ | 3,018 |

For the three and six months ended June 30, 2026, our total research and development expenses increased by $5.8 million and $3.0 million from the comparable prior year periods, respectively. The changes were primarily due to:

•
Revumenib: An increase in the three and six months ended June 30, 2026, from the comparable prior year period, due to frontline trials evaluating revumenib in combination with standard-of-care agents in the treatment of AML;
•
Axatilimab: A decrease in the three months ended June 30, 2026, from the comparable prior year period due to timing of trials and a decrease in the six months ended June 30, 2026, from the comparable prior year period due to a non-recurring $10.0 million development milestone expense recognized in the first quarter of 2025;
•
A decrease in other research and development programs for the three and six months ended June 30, 2026, from the comparable prior year period due to timing of research and development activities;
•
A decrease in personnel cost and other expenses for the three months ended June 30, 2026, from the comparable prior year period due to lower headcount and an increase for the six months ended June 30, 2026, from the comparable prior year period due to costs related to the on-going support of clinical trials and medical affairs; and
•
An increase in stock-based compensation from the comparable prior year period driven by a higher stock price.

Selling, General and Administrative

The following tables summarizes the selling, general and administrative expenses for the three and six months ended June 30, 2026 and 2025:

|  | Three Months Ended June 30, |  |  | Change |  |  | Six Months Ended June 30, |  |  | Change |
|  | 2026 |  |  | 2025 |  |  | $ |  |  | 2026 |  |  | 2025 |  |  | $ |
|  | (In thousands) |  |  | (In thousands) |
Commercial related expenses |  | $ | 9,869 |  |  | $ | 9,874 |  |  | $ | (5 | ) |  | $ | 17,590 |  |  | $ | 20,739 |  |  | $ | (3,149 | )
Other selling, general and administrative expenses |  |  | 5,868 |  |  |  | 5,034 |  |  |  | 834 |  |  |  | 11,008 |  |  |  | 9,405 |  |  |  | 1,603 |
Personnel cost and other expenses |  |  | 16,298 |  |  |  | 19,306 |  |  |  | (3,008 | ) |  |  | 32,999 |  |  |  | 38,389 |  |  |  | (5,390 | )
Stock-based compensation |  |  | 9,504 |  |  |  | 9,591 |  |  |  | (87 | ) |  |  | 17,530 |  |  |  | 16,303 |  |  |  | 1,227 |
Total selling, general and administrative expenses |  | $ | 41,539 |  |  | $ | 43,805 |  |  | $ | (2,266 | ) |  | $ | 79,127 |  |  | $ | 84,836 |  |  | $ | (5,709 | )

23

For the three and six months ended June 30, 2026, our total selling, general and administrative expenses decreased by $2.3 million and $5.7 million, respectively, from the comparable prior year periods. The changes were primarily due to;

•
A decrease in commercial-related expenses due to launch costs incurred in the first quarter of 2025 for Revuforj and Niktimvo that were not incurred in 2026;
•
An increase in other selling, general and administrative expenses from the comparable prior year period to further support corporate growth;
•
A decrease in personnel expenses from the comparable prior year period due to a decrease in overall headcount; and
•
An increase in stock-based compensation for the six months ended June 30, 2026, from the comparable prior year period driven by a higher stock price.

Royalty Interest Expense

For the three and six months ended June 30, 2026, royalty interest expense increased from the comparable prior year period due to the interest expense recognized related to the Royalty Pharma Purchase and Sale Agreement signed in November 2024.

Convertible Note Interest Expense

For the three and six months ended June 30, 2026, convertible note interest expense increased from the comparable prior year period due to the interest expense recognized as a result of the sale and issuance of the convertible notes in June 2026.

Interest Income

For the three and six months ended June 30, 2026, interest income decreased from the comparable prior year period. The decrease of interest income was primarily due to the fluctuation of interest rates and the average balance of cash equivalents and short and long-term investments.

Other Expense

For the three and six months ended June 30, 2026, the total other expense, net decreased from the comparable prior year period primarily due to the fluctuation in foreign currency losses on short- and long-term investments.

Liquidity and Capital Resources

Cash Flows

The following table sets forth the primary sources and uses of cash and cash equivalents for each period set forth below:

|  | Six Months Ended June 30, |
|  | 2026 |  |  | 2025 |
|  | (In thousands) |
Net cash used in operating activities |  | $ | (80,617 | ) |  | $ | (182,957 | )
Net cash provided by investing activities |  |  | 21,476 |  |  |  | 136,029 |
Net cash provided by financing activities |  |  | 260,688 |  |  |  | 1,481 |
Net increase (decrease) cash, cash equivalents and restricted cash |  | $ | 201,547 |  |  | $ | (45,447 | )

Net Cash Used in Operating Activities

Net cash used in operating activities decreased from $183.0 million for the six months ended June 30, 2025 to $80.6 million for the six months ended June 30, 2026, primarily due to a decrease in operating net loss of $64.7 million, as well as decreases in accounts receivable, inventory, and prepaid expenses; offset by decreases in accounts payable and accrued expenses.

Net Cash Provided by Investing Activities

Net cash provided by investing activities for the six months ended June 30, 2026, was $21.5 million and was related to $146.8 million from the maturities of available-for-sale securities, partially offset by the purchase of $125.3 million of available-for-sale securities.

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Net cash provided by investing activities for the six months ended June 30, 2025, was $136.0 million and was related to $238.3 million from the maturities of available-for-sale securities, partially offset by the purchase of $102.3 million of available-for-sale securities.

Net Cash Provided by Financing Activities

Net cash provided by financing activities for the six months ended June 30, 2026, increased by $259.2 million from the comparable prior year period as a result of cash raised from the sale and issuance of convertible notes in June 2026, and proceeds from exercised stock options.

Purchase and Sale Agreement

In October 2024, we entered into a purchase and sale agreement with Royalty Pharma, pursuant to which Royalty Pharma purchased the right to receive 13.8% on quarterly net sales of Niktimvo in the United States and its respective territories, districts, commonwealths and possessions (including Guam and Puerto Rico) in exchange for an upfront payment of $350.0 million (gross) at closing, received in November 2024. Aggregate payments to Royalty Pharma pursuant to the Royalty Agreement will be capped at $822.5 million or 2.35 times the funded amount.

For additional details on our purchase and sale agreement with Royalty Pharma, see Note 12 - “Royalty Interest Financing Liability” to our consolidated financial statements in this Quarterly Report.

Convertible Notes

In June 2026, we issued $250.0 million aggregate principal amount of 2.25% Convertible Senior Notes, or the 2031 Notes, due 2031 in a private placement to institutional accredited investors that were qualified institutional buyers under Rule 144A in reliance on the exemption from registration provided by Section 4(a)(2) of the Securities Act. The 2031 Notes are senior unsecured obligations of ours and bear interest at 2.25% per annum, payable semi-annually in arrears on June 15 and December 15, beginning December 15, 2026. The 2031 Notes mature on June 15, 2031, unless earlier converted, redeemed, or repurchased. The initial conversion rate is 40.3894 shares of common stock per $1,000 principal amount (equivalent to an initial conversion price of approximately $24.76 per share), subject to customary anti-dilution adjustments under certain circumstances in accordance with the terms of the indenture relating to the 2031 Notes. Upon conversion, we will pay or deliver, at our election, cash, shares of our common stock, or a combination of cash and shares of common stock. Before March 15, 2031, the 2031 Notes are convertible only upon the satisfaction of specified conditions; thereafter, the 2031 Notes are convertible at any time until the second scheduled trading day before maturity. We may redeem for cash all or any portion of the 2031 Notes, in whole or in part, on or after June 20, 2029 if the last reported sale price of our common stock exceeds 130% of the conversion price for a specified period at a redemption price equal to 100% of the principal amount of the 2031 Notes to be redeemed, plus accrued and unpaid interest to, but excluding, the redemption date. If we undergo a fundamental change (as defined in the indenture governing the 2031 notes), holders may require us to repurchase their 2031 Notes for cash at a price equal to 100% of the principal amount plus accrued and unpaid interest to, but excluding, the fundamental change repurchase date. Initially, a maximum of 13,631,400 shares of common stock may be issued upon conversion of the 2031 Notes based on the initial maximum conversion rate of 54.5256 shares of common stock per $1,000 principal amount of 2031 Notes, which is subject to customary anti-dilution adjustment provisions. The 2031 Notes are classified as a long-term liability and are presented net of unamortized debt issuance costs, which are amortized to interest expense over the term of the 2031 Notes using the effective interest method.

Future Funding Requirements

We believe that the combination of our available cash, cash equivalents, short- and long-term investments, as well as our expected product revenues from sales of Revuforj and Niktimvo collaboration revenue, is sufficient to fund existing and planned cash requirements. Our primary uses of capital are, and we expect will continue to be, compensation and related expenses, third-party clinical research and development services, clinical costs, commercialization costs, legal and other regulatory expenses and general overhead costs. We have based our estimates on assumptions that may prove to be incorrect, and we could use our capital resources sooner than we currently expect.

Additionally, the process of testing product candidates in clinical trials is costly, and the timing, progress and outcomes in these trials is uncertain. We cannot estimate the actual amounts necessary to successfully complete the development and commercialization of our product candidates or whether, or when, we may achieve profitability.

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Our future capital requirements will depend on many factors, including:

•
our growth rate;
•
the initiation, progress, timing, costs and results of clinical trials of our product candidates;
•
the outcome, timing and cost of seeking and obtaining additional regulatory approvals from the FDA and comparable foreign regulatory authorities, including the potential for such authorities to require that we perform more trials than we currently expect;
•
our ability to satisfy our obligations under the indenture governing the 2031 Notes;
•
the cost to establish, maintain, expand and defend the scope of our intellectual property portfolio, including the amount and timing of any payments we may be required to make, or that we may receive, in connection with licensing, preparing, filing, prosecuting, defending and enforcing any patents or other intellectual property rights;
•
market acceptance of our approved products as well as our product candidates;
•
the cost and timing of selecting, auditing and developing manufacturing capabilities, and potentially validating manufacturing sites for commercial-scale manufacturing;
•
the cost and timing for obtaining pricing and reimbursement, which may require additional trials to address pharmacoeconomic benefit;
•
the cost of maintaining and expanding sales, marketing and distribution capabilities for our products;
•
the costs of acquiring, licensing or investing in additional businesses, products, product candidates and technologies;
•
the interruption of key clinical trial activities, such as clinical trial site monitoring;
•
the cost of disruption to our supply chain and operations, and associated delays in the manufacturing and supply of our products, which would adversely impact our ability to continue our clinical trial operations;
•
the effect of competing technological and market developments; and
•
our need to implement additional internal systems and infrastructure, including financial and reporting systems, as we grow our company.

We expect to continue to support our future cash needs through a combination of equity offerings, debt financings and additional funding from license and collaboration arrangements. Except for any obligations of our collaborators to reimburse us for research and development expenses or to make milestone or royalty payments under our agreements with them, we will not have any committed external source of liquidity.

With respect to our outstanding convertible notes, cash interest payments are payable on a semi-annual basis in arrears, which will require total funding of $5.7 million annually.

Our material contractual obligations and commitments as of June 30, 2026, primarily relate to our maturities of operating leases for office space and equipment and capital leases for office equipment. As of June 30, 2026, we have $0.5 million payable within 12 months.

Except as disclosed above, we have no material non-cancelable purchase commitments with service providers, as we have generally contracted on a cancelable, purchase-order basis. We enter into contracts in the normal course of business with equipment and reagent vendors, CROs, contract manufacturing organizations, and other third parties for clinical trials, preclinical research studies and testing and manufacturing services. These contracts are cancelable by us upon prior notice. Payments due upon cancellation consist only of payments for services provided or expenses incurred, including noncancelable obligations of our service providers, up to the date of cancellation. These payments are not determinable.

We have incurred losses and cumulative negative cash flows from operations since our inception, excluding the year ended December 31, 2021. As of June 30, 2026, we had an accumulated deficit of $1.6 billion. We anticipate that we will likely continue to incur significant losses for at least the next couple years. To the extent that we raise additional capital through the future sale of equity or debt, the ownership interest of our stockholders will be diluted, and the terms of these securities may include liquidation or other preferences that adversely affect the rights of our existing common stockholders. If we raise additional funds through collaboration arrangements in the future, we may have to relinquish valuable rights to our technologies, future revenue streams or product candidates or grant licenses on terms that may not be favorable to us. If we are unable to raise additional funds through equity or debt financings when needed, we may be required to delay, limit, reduce or terminate our product development or future commercialization efforts or grant rights to develop and market product candidates that we would otherwise prefer to develop and market ourselves.

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At-the-Market Offering Program

In May 2023, we entered into a sales agreement with Cowen and Company, LLC, or TD Cowen, under which we could, from time to time, issue and sell shares of our common stock having aggregate sales proceeds of up to $200.0 million, in a series of one or more at-the-market equity offerings, or the 2023 ATM Program. TD Cowen is not required to sell any specific share amounts but acts as the Company’s sales agent, using commercially reasonable efforts consistent with its normal trading and sales practices. Pursuant to the sales agreement, shares will be sold under the shelf registration statement on Form S-3ASR (Registration No. 333-277424), which became automatically effective upon filing on February 27, 2024. Our common stock will be sold at prevailing market prices at the time of the sale, and as a result, prices may vary. For the three and six months ended June 30, 2026, we did not sell any shares of common stock under the 2023 ATM Program. As of June 30, 2026, we had $157.9 million available under the 2023 ATM Program.

Significant Risks and Uncertainties

Unfavorable interest rates and geo-political unrest could result in further economic uncertainty and volatility in the capital markets in the near term and, as a result, could negatively affect our operations and could make it difficult for us to obtain traditional financing on acceptable terms, if at all. Furthermore, such economic conditions have produced downward pressure on share prices. Although we do not believe that inflation has had a material impact on our financial position or results of operations to date, the return of a high inflationary environment could increase our operating costs, including our labor costs and research and development costs. These costs may also be negatively impacted due to supply chain constraints, geopolitical tensions, including tariffs, wars and terrorism, worsening macroeconomic conditions and employee availability and wage increases, which may result in additional stress on our working capital.

Additionally, we are subject to other challenges and risks specific to our business and our ability to execute on our strategy, as well as risks and uncertainties common to companies in the pharmaceutical industry with development and commercial operations, including, without limitation, risks and uncertainties associated with: obtaining regulatory approval of additional indications for our approved products; identifying, acquiring or in-licensing additional products or product candidates; pharmaceutical product development and the inherent uncertainty of clinical success; the challenges of protecting and enhancing our intellectual property rights; and complying with applicable regulatory requirements. See the section titled “Risk Factors” located elsewhere in this report for additional information.

Item 3. Quantitative and Qualitative Disclosures about Market Risk

The market risk inherent in our financial instruments and in our financial position represents the potential loss arising from adverse changes in interest rates. As of June 30, 2026, we had cash, cash equivalents and short- and long-term investments of $575.1 million consisting of $336.5 million of overnight investments, interest-bearing money market funds, short- and long-term investments of $238.6 million, consisting of commercial paper, highly rated corporate bonds and treasuries. Our primary exposure to market risk is interest rate sensitivity, which is affected by changes in the general level of U.S. interest rates. The primary objectives of our investment activities are to ensure liquidity and to preserve principal while at the same time maximizing the interest income, we receive from our marketable securities without significantly increasing risk. We have established guidelines regarding approved investments and maturities of investments, which are designed to maintain safety and liquidity. Due to the relative short-term maturities of our cash equivalents and the low risk profile of our short and long-term investments, an immediate 100 basis point change in interest rates would not have a material effect on the fair market value of our cash equivalents and short and long-term investments. We have the ability to hold our investments until maturity, and therefore, we would not expect our operating results or cash flows to be affected to any significant degree by the effect of a change in market interest rates on our investment portfolio.

We do not believe that inflation and changing prices had a significant impact on our results of operations for any periods presented herein.

Item 4. Controls and Procedures

Disclosure Controls and Procedures and Internal Control over Financial Reporting

Controls and Procedures

We have carried out an evaluation, under the supervision and with the participation of our management, including our principal executive officer and principal financial officer, of the effectiveness of the design and operation of our disclosure controls and procedures (as defined in Rules 13a-15(e) and 15d-15(e) under the Securities Exchange Act of 1934, as amended, or the Exchange Act), as of June 30, 2026. Based upon that evaluation, our principal executive officer and principal financial officer concluded that, as of the end of the period covered by this report, our disclosure controls and procedures are effective in ensuring that:

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(a)
the information required to be disclosed by us in the reports we file or submit under the Exchange Act is recorded, processed, summarized and reported within the time periods specified in the SEC’s rules and forms; and
(b)
the information is accumulated and communicated to our management, including our principal executive officer and principal financial officer as appropriate to allow timely decisions regarding required disclosure.

In designing and evaluating our disclosure controls and procedures, our management recognized that any controls and procedures, no matter how well designed and operated, can provide only reasonable assurance of achieving the desired control objectives, and our management necessarily was required to apply its judgment in evaluating the cost-benefit relationship of possible controls and procedures.

Changes in Internal Control over Financial Reporting

There was no change in our internal control over financial reporting during the quarter ended June 30, 2026, that has materially affected, or is reasonably likely to materially affect, our internal control over financial reporting.

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PART II. OTHE R INFORMATION

Item 1. Legal Proceedings

In the ordinary course of business, we are from time to time involved in lawsuits, claims, investigations, proceedings, and threats of litigation relating to intellectual property, commercial arrangements and other matters. While the outcome of these proceedings and claims cannot be predicted with certainty, as of June 30, 2026, we were not party to any material legal or arbitration proceedings. No governmental proceedings are pending or, to our knowledge, contemplated against us.

Item 1A. Ri sk Factors

In addition to the risk factors listed below and the other information contained elsewhere in this report, you should carefully consider the risks and uncertainties described in “Part I, Item 1A—Risk Factors” of our Annual Report on Form 10-K for the year ended December 31, 2025, or 2025 Form 10-K, filed with the Securities and Exchange Commission, or SEC, on February 26, 2026, which could materially and adversely affect our business, prospects, financial condition and results of operations. New risk factors can emerge from time to time, and it is not possible to predict the impact that any factor or combination of factors may have on our business, prospects, financial condition and results of operations. The risks listed below and described in our 2025 Form 10-K are not our only risks. Additional risks and uncertainties not currently known to us or that we currently deem to be immaterial also may materially adversely affect our business, financial condition or future results. Other than the risk factors listed below, there have been no material changes from the risk factors previously disclosed in our 2025 Form 10-K.

Our indebtedness and liabilities could limit the cash flow available for our operations, expose us to risks that could adversely affect our business, financial condition and results of operations and impair our ability to satisfy our obligations under our indebtedness.

As of June 30, 2026, we had $250.0 million aggregate principal amount of indebtedness under the 2031 Notes. We may also incur additional indebtedness to meet future financing needs. Our indebtedness could have significant negative consequences for our security holders and our business, results of operations and financial condition by, among other things:

•
limiting our ability to obtain additional financing;
•
requiring the dedication of a substantial portion of our cash flow from operations to service our indebtedness, which will reduce the amount of cash available for other purposes;
•
limiting our flexibility to plan for, or react to, changes in our business;
•
diluting the interests of our existing stockholders as a result of issuing shares of our common stock upon conversion of the 2031 Notes;
•
encouraging short selling by market participants because the conversion of the 2031 Notes could be used to satisfy short positions thereby depressing the price of our common stock; and
•
placing us at a possible competitive disadvantage with competitors that are less leveraged than us or have better access to capital.

Our ability to make scheduled payments of the principal of, to pay interest on or to refinance our indebtedness, including the 2031 Notes, depends on our future performance, which is subject to economic, financial, competitive and other factors beyond our control. Our business may not generate sufficient funds, and we may otherwise be unable to maintain sufficient cash reserves, to pay amounts due under our indebtedness, including the 2031 Notes, and our cash needs may increase in the future.

We may not have the ability to raise the funds necessary to settle conversions of the 2031 Notes in cash, to repay the 2031 Notes at maturity or to repurchase the 2031 Notes upon a fundamental change, and our future debt may contain limitations on our ability to pay cash upon conversion or repurchase of the 2031 Notes.

Holders of the 2031 Notes have the right, subject to certain conditions and limited exceptions, to require us to repurchase all or a portion of their Notes upon the occurrence of a fundamental change at a fundamental change repurchase price equal to 100% of the principal amount of the 2031 Notes to be repurchased, plus accrued and unpaid interest, if any. In addition, upon any conversion of the 2031 Notes, unless we elect to deliver solely shares of our common stock to settle such conversion (other than paying cash in lieu of delivering any fractional share), we will be required to make cash payments in respect of the 2031 Notes being converted. We may not have enough available cash or be able to obtain financing at the time we are required to make repurchases of the 2031 Notes surrendered therefor or pay cash with respect to the 2031 Notes being converted or being repaid at maturity. In addition, our ability to repurchase the 2031 Notes or to pay cash upon conversion or at maturity may be limited by law, by regulatory authority, or by agreements governing our future indebtedness. Our failure to repurchase the 2031 Notes at a time when the repurchase is required by the indenture governing

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the 2031 Notes or to pay any cash payable on future conversions of the 2031 Notes or at maturity of the 2031 Notes, as required by the indenture, would constitute a default under the indenture. A default under the indenture or the fundamental change itself could also lead to a default under agreements governing our then-existing indebtedness. If the repayment of the related indebtedness were to be accelerated after any applicable notice or grace periods, we may not have sufficient funds to repay the indebtedness and repurchase the 2031 Notes or make cash payments upon conversions of the 2031 Notes.

The conditional conversion feature of the 2031 Notes, if triggered, may adversely affect our financial condition and operating results.

In the event the conditional conversion feature of the 2031 Notes is triggered, holders of the notes will be entitled to convert their notes at any time during specified periods at their option. If one or more holders elect to convert their Notes, unless we elect to satisfy our conversion obligation by delivering solely shares of our common stock (other than paying cash in lieu of delivering any fractional share), we would be required to settle a portion or all of our conversion obligation in cash, which could adversely affect our liquidity. In addition, even if holders do not elect to convert their notes, we could be required under applicable accounting rules to reclassify all or any portion of the outstanding principal of the notes as a current rather than long-term liability, which would result in a material reduction of our net working capital. Holders of the existing notes have similar conversion rights.

Certain provisions in the indenture governing the 2031 Notes may delay or prevent an otherwise beneficial takeover attempt of us.

Certain provisions in the indenture that governs the 2031 Notes may make it more difficult or expensive for a third party to acquire us. For example, the indenture that governs the 2031 Notes may require us to repurchase the 2031 Notes for cash upon the occurrence of a fundamental change and, in certain circumstances, to increase the conversion rate for a holder that converts its Notes in connection with a make-whole fundamental change. A takeover of us may trigger the requirement that we repurchase the 2031 Notes and/or increase the conversion rate, which could make it costlier for a potential acquirer to engage in such takeover. Such additional costs may have the effect of delaying or preventing a takeover of us that otherwise be beneficial to investors.

The accounting method for the 2031 Notes could adversely affect our reported financial condition and results.

The accounting method for reflecting the 2031 Notes on our consolidated balance sheet, accruing interest expense for the 2031 Notes and reflecting the underlying shares of our common stock in our reported diluted earnings per share may adversely affect our reported earnings and financial condition.

In August 2020, the Financial Accounting Standards Board published Accounting Standards Update (“ASU”) 2020-06 (“ASU 2020-06”), which simplified certain of the accounting standards that apply to convertible notes. In accordance with ASU 2020-06, the 2031 Notes are reflected as a liability on our consolidated balance sheet, with the initial carrying amount equal to the principal amount of the notes, net of issuance costs. Issuance costs are treated as a debt discount for accounting purposes, which are amortized into interest expense over the term of such notes. As a result of this amortization, the interest expense that we expect to recognize for the 2031 Notes for accounting purposes will be greater than the cash interest payments we will pay on the 2031 Notes, which will result in lower reported net income or larger reported net loss.

In addition, the shares of common stock underlying the 2031 Notes are reflected in our diluted earnings per share using the “if converted” method, in accordance with ASU 2020-06, for fiscal periods in which we report net income. Under that method, diluted earnings per share would generally be calculated assuming that all the notes were converted solely into shares of common stock at the beginning of the reporting period, unless the result would be anti-dilutive. The application of the if-converted method may reduce our reported diluted earnings per share to the extent we are profitable in the future.

Furthermore, if any of the conditions to the convertibility of the 2031 Notes is satisfied, then we may be required under applicable accounting standards to reclassify the liability carrying value of such notes as a current, rather than a long-term, liability. This reclassification could be required even if no noteholders convert such notes following the occurrence of those circumstances and could materially reduce our reported working capital.

We cannot be sure whether other changes may be made to the current accounting standards related to the 2031 Notes, or otherwise, that could have a material effect on our reported financial results.

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Item 5. Other Information

Trading Arrangements

During the three months ended June 30, 2026, our directors and officers (as defined in Rule 16a-1 (f) under the Exchange Act) adopted or terminated a “Rule 10b5-1 trading arrangement” or a “non-Rule 10b5-1 trading arrangement,” as defined in Regulation S-K Item 408 for the purchase or sale of our securities as set forth in the table below.

|  |  | Type of Trading Arrangement |  |  |  |  |
Name and Position | Action | Adoption/Termination Date | Rule 10b5-1* | Non- Rule 10b5-1** | Total Shares of Common Stock to be Sold |  | Total Shares of Common Stock to be Purchased |  | Expiration Date
Keith Katkin Director | Adoption**** | 5/18/2026 | X |  |  | 49,000 |  |  | - |  | 5/18/2028

* Contract, instructions, or written plan intended to satisfy the affirmative defense conditions of Rule 10b5-1(c) under the Exchange Act.
** “Non-Rule 10b5-1 trading arrangement” as defined in Item 408(c) of Regulation S-K under the Exchange Act.

1 Mr. Katkin’s plan solely includes equity grants with expiration dates prior to May 23, 2028.

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Item 6. Exhibits

Exhibit No. |  | Description
3.1 |  | Amended and Restated Certificate of Incorporation of the Company (incorporated herein by reference to Exhibit 3.1 to the Company’s Current Report on Form 8-K (File No. 001-37708), as filed with the SEC on March 8, 2016).
3.2 |  | Certificate of Amendment to the Amended and Restated Certificate of Incorporation of the Company (incorporated herein by reference to Exhibit 3.1 to the Company’s Current Report on Form 8-K (File No. 001-37708), as filed with the SEC on May 18, 2023).
4.1 |  | Indenture, dated as of June 10, 2026, by and between Syndax Pharmaceuticals, Inc. and U.S. Bank Trust Company, National Association, as Trustee (incorporated herein by reference to Exhibit 4.1 to the Company’s Current Report on Form 8-K (File No. 001-37708), as filed with the SEC on June 10, 2026).
4.2 |  | Form of Global Note, representing Syndax Pharmaceuticals, Inc.’s 2.25% Convertible Senior Notes due 2031 (included as Exhibit A to the Indenture files as Exhibit 4.1) (incorporated herein by reference to Exhibit 4.2 to the Company’s Current Report on Form 8-K (File No. 001-37708), as filed with the SEC on June 10, 2026.
10.1 |  | Syndax Pharmaceuticals, Inc. 2026 Equity Incentive Plan (incorporated herein by reference to Exhibit 10.1 to the Company’s Current Report on Form 8-K (File No. 001-37708), as filed with the SEC on June 10, 2026).
10.2 |  | Forms of Stock Option Grant Notice and Stock Option Agreement pursuant to the Syndax Pharmaceuticals, Inc. 2026 Equity Incentive Plan.
10.3 |  | Forms of RSU Award Grant Notice and Award Agreement pursuant to the Syndax Pharmaceuticals, Inc. 2026 Equity Incentive Plan.
10.4 |  | Forms of Deferred Settlement RSU Award Grant Notice and Award Agreement pursuant to the Syndax Pharmaceuticals, Inc. 2026 Equity Incentive Plan.
10.5 |  | Syndax Pharmaceuticals, Inc. 2026 Employee Stock Purchase Plan (incorporated herein by reference to Exhibit 10.2 to the Company’s Current Report on Form 8-K (File No. 001-37708), as filed with the SEC on June 10, 2026).
3.3 |  | Amended and Restated Bylaws of the Company (incorporated herein by reference to Exhibit 3.1 to the Company’s Current Report on Form 8-K (File No. 001-37708), as filed with the SEC on December 19, 2025).
31.1 |  | Certification of Principal Executive Officer pursuant to Rules 13a-14(a) and 15d-14(a) promulgated under the Securities Exchange Act of 1934, as amended.
31.2 |  | Certification of Principal Financial Officer pursuant to Rules 13a-14(a) and 15d-14(a) promulgated under the Securities Exchange Act of 1934, as amended.
32.1* |  | Certifications of Chief Executive Officer and Chief Financial Officer pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002.
101.INS |  | Inline XBRL Instance Document - the instance document does not appear in the Interactive Data File as its XBRL tags are embedded within the Inline XBRL Document.
101.SCH |  | Inline XBRL Taxonomy Extension Schema With Embedded Linkbase Documents
104 |  | Cover page formatted as Inline XBRL and contained in Exhibit 101.

* Furnished herewith and not deemed to be “filed” for purposes of Section 18 of the Exchange Act, or otherwise subject to the liability of that section, and shall not be deemed to be incorporated by reference into any filing under the Securities Act of 1933, as amended, or the Exchange Act (whether made before or after the date of the Form 10-Q), irrespective of any general incorporation language contained in such filing.

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SIGNATURES

Pursuant to the requirements of Section 13 or 15(d) of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

Date: August 4, 2026

By: |  | /s/ Michael A. Metzger
|  | Michael A. Metzger
|  | Chief Executive Officer
|  | (Principal Executive Officer)

By: |  | /s/ Keith A. Goldan
|  | Keith A. Goldan
|  | Chief Financial Officer and Treasurer
|  | (Principal Financial Officer and Principal Accounting Officer)

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