Exhibit 4.2

1+1 Industry Canada Industria Canada Date orAmendment (Y_,Y.,..,.Y,..,.Y,...,.&...M,...,.,M... -DD) Canada Certificate of Amendment Certificat de modification Canada Business Corporations Act Lol canadlenne sur les socletes par actions AETERNA ZENTARIS INC. Corporate n11111c I Denomination sociale 264271-9 Corporation number I Numero de societe I HEREBY CERTIFY that the articles of the JE CERTIFIE que les statuts de Ia societe above named corporation are amended under susmentionnee sont modifies aux termes de section 178 of the Canada Business !'article 178 de Ia Loi canadienne sur les Corporations Act as set out in the attached socifltes par actions, tel qu'il est indique dans les articles of amendment. clauses modificatrices ci jointes. Marcie Girouard Director I Direcleur 2012-10-02 Date de modification (AAAA-MM-JJ)

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