Exhibit 12.3
Certification of the Principal Executive Officer pursuant to §302 of the Sarbanes-Oxley Act of 2002Certification
I, Klaus Paulini, certify that:
| 1. | I have reviewed this Amendment No. 1 on Form 20-F of Aeterna Zentaris Inc.; and |
| 2. | Based on my knowledge, this report does not contain any untrue statement of a material fact or omit to state 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: June 18, 2020
| /s/ Klaus Paulini | |
| Klaus Paulini | |
| President and Chief Executive Officer |
