Exhibit 31.3
Certification of Principal Executive Officer
I, Richard J. Daly, certify that:
| 1. | I have reviewed this Amendment No. 1 to Annual Report on Form 10-K of Catalyst Pharmaceuticals, Inc. |
| 2. | Based on my knowledge, this report does not contain any untrue statement of a material fact necessary to make the statements made, in light of the circumstances under which such statements were made, not misleading with respect to the period covered by this report. |
| Date: April 30, 2026 |
| /s/ Richard J. Daly |
| Richard J. Daly |
| President and Chief Executive Officer |
| (Principal Executive Officer) |