| Name | Relationship | Address | Signature | Signature date | CIK |
|---|---|---|---|---|---|
| Metzger Michael A | Chief Executive Officer, Director | C/O SYNDAX PHARMACEUTICALS, INC., 730 3RD AVENUE, FLOOR 9, NEW YORK | /s/ Michael A. Metzger | 10 Feb 2026 | 0001507220 |
| Type | Sym | Class | Transaction | Value $ | Shares | Change % | * Price $ | Shares After | Date | Ownership | Footnotes |
|---|---|---|---|---|---|---|---|---|---|---|---|
| transaction | SNDX | Common Stock | Sale | $360,819 | -17,159 | -3.4% | $21.03 | 491,690 | 09 Feb 2026 | Direct | F1 |
| Id | Content |
|---|---|
| F1 | Represents the number of shares required to be sold by the reporting person to cover tax withholding obligations in connection with the vesting of restricted stock units. |