**Exhibit 4.1**

**STOCK OPTION PLAN OFÆTERNA ZENTARIS INC.**

 
| **1.**     | **Purpose of the Plan**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |
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| ** ** | ** **                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
| 1.1        | The purpose  of the stock option plan for directors, officers, employees, members of the  Scientific Board and suppliers of ongoing services (the **“Plan”**)  of Æterna Zentaris Inc. (the **“Corporation”**)  is to secure for the Corporation and its shareholders the benefit of an  incentive interest in share ownership by directors, officers and employees of  the Corporation and its Subsidiaries, as the case may be, and by the members  of the Scientific Board and certain designated suppliers of ongoing services.                                                                                                                                                                                                                                                     |
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| **2.**     | **Administration**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               |
| ** ** | ** **                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
| 2.1        | The Plan  shall be administered by the Corporation’s Board of Directors (the “**Board**”) or the Corporate Governance, Nominating and Human  Resources Committee, as the same may be constituted from time to time (the “**Committee**”). The Board or the Committee shall have full  and complete latitude to interpret the Plan and to establish the  rules and regulations applying to it and to make all other  determinations it deems necessary or useful for the administration of the  Plan, provided that such interpretations, rules, regulations and  determinations shall be consistent with the relevant policy statements of the  competent securities authorities and the rules of the stock exchanges on  which the securities of the Corporation are listed. |
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| **3.**     | **Shares Subject to the Plan**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |
| ** ** | ** **                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
| 3.1        | The shares  issuable further to the exercise of options granted under the Plan are the  Common Shares of the Corporation (the “**Shares**”). The  total number of Shares that may be issued under the Plan shall not exceed 10%  of the total number of issued and outstanding Shares at any given time. No  Optionee (as defined hereinbelow) shall hold options to purchase more than  five percent (5%) of the number of Shares issued and outstanding from time to  time.                                                                                                                                                                                                                                                                                                                          |
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| 3.2        | In addition:  (i) the number of securities issuable to “insiders” (as such term is  defined in the TSX Company Manual) of the Corporation, at any time, under all  security-based compensation arrangements of the Corporation, cannot exceed  (ten percent) 10% of its issued and outstanding securities; and (ii) the  number of securities issued to insiders of the Corporation, within any  one-year period, under all security-based compensation arrangements of the  Corporation, cannot exceed 10% of its issued and outstanding securities.                                                                                                                                                                                                                                        |
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| 3.3        | All options  that are exercised, or that expire or are cancelled without being exercised,  shall become available to be granted (or “reloaded”) under the terms of the  Plan upon such exercise, cancellation or expiration, as the case may be.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |

 

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| **4.**     | **Grant of Options**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |
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| ** ** | ** **                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |
| 4.1        | The Board or the Committee shall from to  time designate the directors, officers or employees of the Corporation or any  of its Subsidiaries, as the case may be, or the members of the Scientific  Board or suppliers of ongoing services to whom options shall be granted (an “**Optionee**”) and the number of Shares covered by each of  such options. For the purposes of the Plan, “**Subsidiaries**”  shall mean any legal entity of which the Corporation holds or is the  beneficiary, at any time, directly or indirectly, otherwise than as security  only, of securities conferring over 50% of the votes enabling it to elect the  majority of the directors of such entity as well as any current or future  Subsidiary of such legal entity. Any Optionee may hold more than one option.  The granting of each option shall be evidenced by a letter from the  Corporation addressed to the Optionee setting forth the number of Shares  covered by such option, the subscription price, the terms and conditions of  exercise of the option and the option period. |
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| **5.**     | **Exercise  Price**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |
| ** ** | ** **                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |
| 5.1        | The exercise  price of an option shall be established by the Board or the Committee at the  time of the grant and this price shall not be less than the greater of the  closing prices of the Shares on the Toronto Stock Exchange and the Nasdaq  National Market on the last trading day preceding the date of grant of the  option (the “**Grant Date**”). If either of these  exchanges is closed or if the Shares did not trade on one of the two  exchanges on the last trading day preceding the Grant Date, the exercise  price shall be the closing price of the Shares at the open exchange (“**Exercise Price**”).                                                                                                                                                                                                                                                                                                                                                                                                                                                      |
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|       | The closing  price of the Shares shall be converted into Canadian dollars, when this  conversion is required, at the noon buying rate of the Bank of Canada on the  last trading day preceding the Grant Date established in the previous  paragraph.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |
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| **6.**     | **Option Period**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |
| ** ** | ** **                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |
| 6.1        | Subject to  the provisions of Section 6.2, each option shall be exercisable during a  period established by the Board or the Committee (the “**Option  Period**”). The Option Period shall commence no earlier than the  Grant Date and shall terminate no later than ten years after such date (the “**Outside Expiry Date**”).                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |
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| 6.2        | Notwithstanding  the provisions of Section 6.1, an option shall not be exercisable by an  Optionee from and after each and every one of the following dates (an “**Early Expiry Date**”), unless the Board or the Committee  decides otherwise:                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |
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|       | 6.2.1                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  | (i) in the case where the Optionee is an officer or an employee,  the date on which the Optionee resigns or voluntarily leaves his employment  with the Corporation or one of its Subsidiaries, as the case may be, or the  date on which the employment of the Optionee with the Corporation or one of  its Subsidiaries is terminated for just cause, as the case may be, including,  without limiting the scope of the foregoing, in the event of a breach of his  obligations to the Corporation, or (ii) in the case where the Optionee  is a director or a member of the Scientific Board of the Corporation or one  of its Subsidiaries, as the case may be, but is not employed by either the  Corporation or one of its Subsidiaries, the date on which such Optionee |

 

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|       |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         | ceases to be a member of the relevant Board of Directors or the  Scientific Board for any reason other than death;                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |
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|       | 6.2.2                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | (i) in the case where the Optionee is an officer or employee,  six (6) months following the date on which the Optionee’s employment with  the Corporation or any of its Subsidiaries, as the case may be, is terminated  by reason of death or (ii) in the case where the Optionee is a director  or a member of the Scientific Board of the Corporation or any of its  Subsidiaries, as the case may be, but is not employed by either the  Corporation or any of its Subsidiaries, six (6) months following the  date on which such Optionee ceases to be a member of the relevant Board of  Directors by reason of death; |
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|       | 6.2.3                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | in the case where the Optionee is an officer or employee, thirty (30)  days following the date on which the Optionee’s employment with the  Corporation or any of its Subsidiaries, as the case may be, is terminated for  any cause or reason other than those mentioned in paragraphs 6.2.1 and 6.2.2  including, without limiting the scope of the foregoing, disability, long-term  illness, retirement or early retirement; or                                                                                                                                                                                                              |
|       |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |
|       | 6.2.4                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | in the case where the Optionee is a supplier of ongoing services,  thirty (30) days following the date on which the Optionee ceases to act as a  supplier of ongoing services to the Corporation or any of its Subsidiaries,  as the case may be, for any cause or reason.                                                                                                                                                                                                                                                                                                                                                                            |
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| 6.3        | Subject to  Section 6.4 hereof, all rights conferred by an option under the Plan  that shall not have been exercised by either an Early Expiry Date or the  Outside Expiry Date shall be forfeited and cancelled.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
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| 6.4        | If an Early  Expiry Date or the Outside Expiry Date applicable to any option granted under  the Plan falls within a blackout period imposed by the Corporation under the  Corporation’s trading restrictions and blackout periods policy (as such  policy may be amended from time to time by the Corporation), or within seven  (7) business days immediately following such a blackout period, then the  applicable Early Expiry Date or the Outside Expiry Date, as the case may be,  will be automatically extended to the date which is seven (7) business  days after the last day of the blackout period. The seven (7) business  day extension period established in this paragraph is a fixed period which is  not subject to Board discretion. |
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| **7.**     | **Exercise of Options**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |
| ** ** | ** **                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |
| 7.1        | Subject to  the provisions of Section 6, an option may be exercised in whole, at any  time, or in part, from time to time, during the Option Period, but in all cases  in accordance with the exercise schedule established by the Board or the  Committee and applicable at the time of the grant.                                                                                                                                                                                                                                                                                                                                                                                                                                                                     |
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| 7.2        | An option  may be exercised by written notice to the Secretary of the Corporation. Such  notice shall set forth the number of options exercised and the number of  underlying Shares subscribed for pursuant to such exercise and the address to  which the certificate evidencing such Shares is to be delivered. Such notice  shall also be accompanied by a certified cheque made payable to the  Corporation in the amount of                                                                                                                                                                                                                                                                                                                                            |

 

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|                                                                                                                                  | the Exercise  Price. The Corporation shall cause a certificate for the number of Shares  specified in the notice to be issued in the name of the Optionee and  delivered to the address specified in the notice no later than ten  (10) business days following the receipt of such notice and cheque.                                                                                        |
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| **8.**                                                                                                                                | **No  Assignment**                                                                                                                                                                                                                                                                                                                                                                                 |
| ** **                                                                                                                            | ** **                                                                                                                                                                                                                                                                                                                                                                                         |
| 8.1                                                                                                                                   | No option or  interest therein shall be assignable by the Optionee other than by will or in  accordance with the applicable laws of estates and succession.                                                                                                                                                                                                                                        |
|                                                                                                                                  |                                                                                                                                                                                                                                                                                                                                                                                               |
| **9.**                                                                                                                                | **Not a  Shareholder**                                                                                                                                                                                                                                                                                                                                                                             |
| ** **                                                                                                                            | ** **                                                                                                                                                                                                                                                                                                                                                                                         |
| 9.1                                                                                                                                   | An Optionee  shall have no rights as a shareholder of the Corporation with respect to any  Shares covered by his/her option until he/she shall have become the holder of  record of such Shares.                                                                                                                                                                                                   |
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| **10.**                                                                                                                               | **Offer for Shares of the  Corporation**                                                                                                                                                                                                                                                                                                                                                           |
| ** **                                                                                                                            | ** **                                                                                                                                                                                                                                                                                                                                                                                         |
| 10.1                                                                                                                                  | In the event  that, at any time, an offer to purchase is made to all holders of Shares,  notice of such offer shall be given by the Corporation to each Optionee and  all unexercised options will become exercisable immediately at the Exercise  Price, but only to the extent necessary to enable an Optionee to tender  his/her Shares in response to the offer should the Optionee so desire. |
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| **11.**                                                                                                                               | **Modification of the Plan**                                                                                                                                                                                                                                                                                                                                                                       |
| ** **                                                                                                                            | ** **                                                                                                                                                                                                                                                                                                                                                                                         |
| Board,  shareholder and requisite regulatory approvals shall be required for any of  the following amendments to be made to the Plan: |
|                                                                                                                                  |                                                                                                                                                                                                                                                                                                                                                                                               |
| 11.1                                                                                                                                  | any  amendment to Section 3.2 that would have the effect of permitting,  without having to obtain shareholder approval on a “disinterested vote” at a  duly convened shareholders’ meeting, the grant of any option(s) under  this Plan otherwise prohibited by Section 3.2;                                                                                         |
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| 11.2                                                                                                                                  | any  amendment to the number of securities issuable under the Plan (except for any  adjustment described in paragraph 12.1.5 hereof);                                                                                                                                                                                                                                                              |
|                                                                                                                                  |                                                                                                                                                                                                                                                                                                                                                                                               |
| 11.3                                                                                                                                  | any  amendment which would permit any option granted under the Plan to be  transferable or assignable other than by will or in accordance with the  applicable laws of estates and succession;                                                                                                                                                                                                     |
|                                                                                                                                  |                                                                                                                                                                                                                                                                                                                                                                                               |
| 11.4                                                                                                                                  | the addition  of a cashless exercise feature, payable in cash or securities, which does not  provide for a full deduction of the number of underlying securities from the  Plan reserve;                                                                                                                                                                                                           |
|                                                                                                                                  |                                                                                                                                                                                                                                                                                                                                                                                               |
| 11.5                                                                                                                                  | the addition  of a deferred or restricted share unit or any other provision which results  in employees receiving securities while no cash consideration is received by  the Corporation;                                                                                                                                                                                                          |
|                                                                                                                                  |                                                                                                                                                                                                                                                                                                                                                                                               |
| 11.6                                                                                                                                  | with respect  to an Optionee who is an “insider” of the Corporation,                                                                                                                                                                                                                                                                                                                     |

 

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|       | (i)                                                                                                                                                                                                                                                    | any  reduction in the exercise price of any option after the option has been  granted, or                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |
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|       |                                                                                                                                                                                                                                                   |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
|       | (ii)                                                                                                                                                                                                                                                   | any  cancellation of an option and the regrant of that option under different  terms, except if such regrant occurs at least three (3) months after the  related cancellation,                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        |
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|       | except in  respect of any adjustment described in paragraph 12.1.5 hereof;                                                                                                                                                                             |
|       |                                                                                                                                                                                                                                                   |
| 11.7       | any  extension to the term of an option beyond the Outside Expiry Date to an  Optionee who is an “insider” of the Corporation (except for extensions made  pursuant to Section 6.4);                                                    |
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| 11.8       | any  amendment to the method of determining the exercise price of an option  granted pursuant to the Plan;                                                                                                                                             |
|       |                                                                                                                                                                                                                                                   |
| 11.9       | the addition  of any form of financial assistance or any amendment to a financial  assistance provision which is more favourable to employees; and                                                                                                     |
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| 11.10      | any  amendment to this Section 11.                                                                                                                                                                                                                |
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| **12.**    | **Amendments  and Termination**                                                                                                                                                                                                                        |
| ** ** | ** **                                                                                                                                                                                                                                             |
| 12.1       | The Board may,  subject to receipt of requisite regulatory approval, where required, in its  sole discretion, make all other amendments to the plan that are not  contemplated in Section 11 above including, without limitation, the  following: |
|       |                                                                                                                                                                                                                                                   |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
|       | 12.1.1                                                                                                                                                                                                                                                 | amendments of a “housekeeping” or clerical nature or to clarify the  Plan’s provisions;                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     |
|       |                                                                                                                                                                                                                                                   |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
|       | 12.1.2                                                                                                                                                                                                                                                 | amendments regarding any vesting period of an option;                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |
|       |                                                                                                                                                                                                                                                   |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
|       | 12.1.3                                                                                                                                                                                                                                                 | amendments regarding the extension of an option beyond an Early  Expiry Date in respect of any Optionee, or the extension of an option beyond  the Outside Expiry Date in respect of any Optionee who is a “non-insider” of  the Corporation;                                                                                                                                                                                                                                                                                                                                                                                                                    |
|       |                                                                                                                                                                                                                                                   |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
|       | 12.1.4                                                                                                                                                                                                                                                 | with respect to any Optionee who is a “non-insider” of the  Corporation, amendments to the terms of an option to reduce the exercise  price of such option after the option has been granted, or to cancel an  option and regrant that option under different terms;                                                                                                                                                                                                                                                                                                                                                                                             |
|       |                                                                                                                                                                                                                                                   |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
|       | 12.1.5                                                                                                                                                                                                                                                 | adjustments to the number of issuable Shares underlying, or the  exercise price of, outstanding options resulting from a split or a  consolidation of the Shares, a reclassification, the payment of a stock  dividend, the payment of a special cash or non-cash distribution to the  Corporation’s shareholders on a pro rata basis provided such distribution is  approved by the Corporation’s shareholders in accordance with applicable law,  a recapitalization, a reorganization or any other event which necessitates an  equitable adjustment to the outstanding options in proportion with  corresponding adjustments made to all outstanding Shares; |
|            |                                                                                                                                                                                                                                                        |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |  |

 

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|       | 12.1.6                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      | discontinuing or terminating the Plan; and                                                     |
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|       |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        |                                                                                           |
|       | 12.1.7                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      | any other amendment which does not require shareholder approval under  Section 11 hereof. |
|       |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        |
| 12.2       | Notwithstanding  Section 12.1 above, the Corporation shall not contravene any  requirements, rules, laws and regulations of the TSX or of any regulatory  authorities.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 |
|       |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        |
| 12.3       | Notwithstanding  any provisions to the contrary, any amendment to or termination of the Plan  shall in no way amend or otherwise affect the conditions of the options  already granted under the Plan to the extent that such options have not then  been exercised, unless the rights of the optionee have already expired or  have already been fully exercised or unless the optionee affected by such  change has already agreed to it.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 |
|       |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        |
| **13.**    | **Miscellaneous Provisions**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |
| ** ** | ** **                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |
| 13.1       | The  Corporation’s obligations under the terms of the Plan are subject to all  applicable laws, regulations or rules of any governmental agency or  other competent authority in respect of the issuance or distribution of  securities and to the rules of any stock exchange on which the Shares  are listed. Each Optionee shall agree to comply with such laws, regulations  and rules and to provide to the Corporation any information or  undertaking required to comply with such laws, regulations and rules.                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |
|       |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        |
| 13.2       | The  participation in the Plan of a director, an officer, an employee or a member  of the Scientific Board of the Corporation or any of its Subsidiaries shall  be entirely optional and shall not be interpreted as conferring upon a  director, an officer, an employee or a member of the Scientific Board of the  Corporation or any of its Subsidiaries any right or privilege whatsoever,  except for the rights and privileges set out expressly in the Plan. Neither  the Plan nor any act that is done under the terms of the Plan shall be  interpreted as restricting the right of the Corporation or any of its  Subsidiaries to terminate the employment of an officer or employee at any  time. Any notice of dismissal given to an officer or employee at the time  his/her employment is terminated, or any payment in the place and stead of  such notice, or any combination of the two, shall not have the effect of  extending the duration of the employment for purposes of the Plan. |
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| 13.3       | No director,  officer, employee or member of the Scientific Board of the Corporation or any  of its Subsidiaries shall acquire the automatic right to be granted one or  more options under the terms of the Plan by reason of any previous grant of  options under the terms of the Plan.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |
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| 13.4       | The Plan  does not provide for any guarantee in respect of any loss or profit which may  result from fluctuations in the price of the Shares.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               |
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| 13.5       | The  Corporation and its Subsidiaries shall assume no responsibility as regards  the tax consequences that participation in the Plan will have for a director,  an officer, an employee or a member of the Scientific Board of the  Corporation or any of its Subsidiaries, and such persons are urged to consult  their own tax advisors in such regard.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |

 

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| 13.6   | The Plan and  any option granted under the terms of the Plan shall be governed and  interpreted according to the laws of the Province of Quebec and the laws of  Canada applicable thereto.                                                              |
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| 13.7   | Once  approved by the Corporation’s shareholders, the Plan will modify the stock  option plan adopted by the Corporation on November 7, 1995 as amended.  This Plan confers no other advantage to the beneficiaries of the stock option  plan. |

 

Dated February 28, 2007

 

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**STOCK OPTION PLAN**

 

**OF ÆTERNA ZENTARIS INC.**

 

SUBSCRIPTION FORM

 

(Date)

 

ÆternaZentaris Inc.1405 boul. du Parc-TechnologiqueQuébec, QuébecG1P 4P5

 

Attention ofthe Secretary

 

I, theundersigned,                                        ,hereby exercise                    options and subscribe for                    Common Shares of Æterna Zentaris Inc. (the “Corporation”) pursuant to theexercise of such options under the terms of the Stock Option Plan of theCorporation, out of the                      Common Shares available for purchase by the undersigned, and I enclose herewithmy certified cheque (or money order) made payable to the order of ÆternaZentaris Inc., in the amount of                                                                dollars in payment of the said subscription.

 

 
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·      The French version of this Scheduleshall prevail.

 

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