COSCIENS Biopharma (CSCI) 20-F 2011 FY Annual report (foreign)

Exhibit 13.1

Certification of the Principal Executive Officer pursuant to 18 U.S.C. Section 1350 as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002

CERTIFICATION PURSUANT TO

18 U.S.C. SECTION 1350,

AS ADOPTED PURSUANT TO

SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002

In connection with the annual report of Aeterna Zentaris Inc. (the “Company”) on Form 20-F for the year ended December 31, 2011 as filed with the Securities and Exchange Commission on the date hereof (the “Report”), I, Juergen Engel, President and Chief Executive Officer of the Company, certify, pursuant to 18 U.S.C. § 1350, as adopted pursuant to § 906 of the Sarbanes-Oxley Act of 2002, that:

(1) The Report fully complies with the requirements of Section 13(a) or 15(d) of the Securities Exchange Act of 1934; and

(2) The information contained in the Report fairly presents, in all material respects, the financial condition and results of operations of the Company.

Dated: March 27, 2012

/s/ Juergen Engel

Prof. Dr. Juergen Engel

President and Chief Executive Officer