SECURITIES PURCHASE AGREEMENT
This Securities Purchase Agreement (this “ Agreement ”) is dated as of June 15, 2010, between Æterna
Zentaris Inc., a Canadian corporation (the “ Company ”), and each purchaser identified on the signature pages
hereto (each, including its successors and assigns, a “ Purchaser ” and collectively the “ Purchasers ”).
WHEREAS, subject to the terms and conditions set forth in this Agreement and pursuant to an effective
registration statement on Form F-3 under the Securities Act of 1933, as amended (the “ Securities Act ”), the
Company desires to issue and sell to each Purchaser, and each Purchaser, severally and not jointly, desires to
purchase from the Company, securities of the Company as more fully described in this Agreement.
NOW, THEREFORE, IN CONSIDERATION of the mutual covenants contained in this Agreement, and for
other good and valuable consideration the receipt and adequacy of which are hereby acknowledged, the
Company and each Purchaser agree as follows:
1.1 Definitions . In addition to the terms defined elsewhere in this Agreement, for all purposes of this
Agreement, the following terms have the meanings set forth in this Section 1.1:
“ Action ” shall have the meaning ascribed to such term in Section 3.1(j).
“ Affiliate ” means any Person that, directly or indirectly through one or more intermediaries, controls or is
controlled by or is under common control with a Person as such terms are used in and construed under
Rule 405 under the Securities Act.
“ Board of Directors ” means the board of directors of the Company.
“ Business Day ” means any day except any Saturday, any Sunday, any day which is a federal legal holiday
in the United States or any day on which banking institutions in the State of New York are authorized or
required by law or other governmental action to close.
“ Closing ” means the closing of the purchase and sale of the Securities pursuant to