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                    U.S. SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549
                                  FORM 40-F/A

                                AMENDMENT NO. 1

[Check one]
          [ ] REGISTRATION STATEMENT PURSUANT TO SECTION 12 OF THE
                       SECURITIES EXCHANGE ACT OF 1934

                                       OR

          [X] ANNUAL REPORT PURSUANT TO SECTION 13(a) OR 15(d) OF THE
                        SECURITIES EXCHANGE ACT OF 1934

For the fiscal year ended December 31, 2003       Commission File Number 0-30752

                              AETERNA ZENTARIS INC.
                   (Formerly named AEterna Laboratories Inc.)

             (Exact name of registrant as specified in its charter)

         CANADA                     2834                   NOT APPLICABLE
  (Province or other     (Primary Standard Industrial     (I.R.S. Employer
   jurisdiction of        Classification Code Number)   Identification Number)
   incorporation or
    organization)

                       1405, boul. du Parc-Technologique
                                Quebec, Quebec
                                Canada, G1P 4P5
                                (418) 652-8525
(Address and telephone number of Registrant's principal executive offices)

                             CT Corporation System
                               111 Eighth Avenue
                                  13th Floor
                            New York, New York 10011
                                (212) 894-8638
            (Name, address and telephone number of agent for service of
                          process in the United States)

Securities registered or to be registered pursuant to Section 12(b) of the Act.

    TITLE OF EACH CLASS            NAME OF EACH EXCHANGE ON WHICH REGISTERED
      Not Applicable                             Not Applicable

             Securities registered or to be registered pursuant to
                             Section 12(g) of the Act.

                             SUBORDINATE VOTING SHARES
                                 (Title of Class)

             Securities for which there is a reporting obligation
                    pursuant to Section 15(d) of the Act.

                                 NOT APPLICABLE
                                (Title of Class)

                For annual reports, indicate by check mark the
                      information filed with this Form:

     [X] Annual information form        [X] Audited annual financial statements

         Indicate the number of outstanding shares of each of the issuer's
classes of capital or common stock as of the close of the period covered by
the annual report.

                45,330,992 Subordinate Voting Shares Outstanding
                      0 Multiple Voting Shares Outstanding
                            0 First Preferred Shares
                            0 Second Preferred Shares

         Indicate by check mark whether the Registrant by filing the
information contained in this Form is also thereby furnishing the information
to the Commission pursuant to Rule 12g3-2(b) under the Securities Exchange
Act of 1934 (the "Exchange Act"). If "Yes" is marked, indicate the filing
number assigned to the Registrant in connection with such Rule.

                           Yes          No   X
                               -----       -----

         Indicate by check mark whether the Registrant (1) has filed all
reports required to be filed by Section 13 or 15(d) of the Exchange Act
during the preceding 12 months (or for such shorter period that the
Registrant was required to file such reports) and (2) has been subject to
such filing requirements for the past 90 days.

                           Yes   X      No
                               -----       -----
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                                EXPLANATORY NOTE


     The sole purposes of this Amendment No. 1 on Form 40F/A (this "Amendment")
to the Annual Report on Form 40-F (the "Annual Report") of AEterna Zentaris Inc.
(formerly named AEterna Laboratories Inc.) (the "Registrant") for the fiscal
year ended December 31, 2003 is:

     (i)  to include the disclosure provided under "Corporate Governance" below;
and

     (ii) to amend and restate the certifications attached as Exhibits 31.1 and
31.2 to the Registrant's Annual Report to conform to the language set forth in
General Instruction B.(6) of Form 40-F, and as provided in the final rule
adopted by the Securities and Exchange Commission as set forth in Release No.
33-8238, entitled "Management's Reports on Internal Control Over Financial
Reporting and Certification of Disclosure in Exchange Act Periodic Reports."


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                            AETERNA LABORATORIES INC.
                        (NOW NAMED AETERNA ZENTARIS INC.)

                           ANNUAL REPORT ON FORM 40-F


                             CONTROLS AND PROCEDURES

     The Registrant's President and Chief Executive Officer and the Registrant's
Vice President and Chief Financial Officer have concluded, based on their
evaluation of the effectiveness of the Registrant's disclosure controls and
procedures (as defined in Rule 13a-15(e) and 15d-15(e) under the Securities
Exchange Act of 1934, as amended), that the Registrant's disclosure controls and
procedures are effective as of the end of the period covered by this annual
report on Form 40-F.

     There has been no change in the Registrant's internal control over
financial reporting that occurred during the period covered by this annual
report on Form 40-F that has materially affected, or is reasonably likely to
materially affect, the Registrant's internal control over financial reporting.


                              CORPORATE GOVERNANCE

     The Registrant is in compliance with the corporate governance requirements
of The Nasdaq Stock Market, Inc. ("NASDAQ") except for the requirement that a
quorum for a meeting of the holders of the common stock of the Registrant be no
less than 331/3% of such outstanding shares. The by-laws of the Registrant
provide that a quorum for purposes of any meeting of shareholders of the
Registrant consists of at least 20% of the outstanding voting shares. The
Registrant received an exemption from NASDAQ from this quorum requirement
because the quorum provided for in the by-laws of the Registrant is consistent
with generally accepted business practices in Canada, the Registrant's country
of domicile, and with the Toronto Stock Exchange, the principal market on which
the Registrant's voting shares are traded.


                             CODE OF ETHICAL CONDUCT

     On March 29, 2004, the Board of Directors adopted a "Code of Ethical
Conduct", a copy of which is attached as Exhibit 7 to this annual report on Form
40-F and which is also available on the Registrant's website at
www.aeternazentaris.com (formerly www.aeterna.com) in Investors/Shareholder
Info. The Code of Ethical Conduct is a "code of ethics" as defined in paragraph
(9)(b) of General Instruction B to Form 40-F. The Code of Ethical Conduct
applies to all of the Registrant's employees, directors and officers, including
the Registrant's principal executive officer, principal financial officer, and
principal accounting officer or controller, or persons performing similar
functions, and includes specific provisions dealing with integrity in accounting
matters, conflicts of interest and compliance with applicable laws and
regulations. The Registrant will provide this document to any person or company
upon request to the Corporate Secretary of the Registrant, at its head office at
1405 boulevard du Parc-Technologique, Quebec City, Quebec, G1P 4P5.



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                                 AUDIT COMMITTEE

     The Registrant has a separately designated standing Audit Committee
established in accordance with Section 3(a)(58)(A) of the Exchange Act. The
Audit Committee consists of three members: Mr. Francis Bellido, Ms. Stormy
Byorum and Mr. Pierre MacDonald. The Audit Committee is composed entirely of
outside, non-management directors who are also unrelated directors. The Board of
Directors is of the view that each of the members of the Audit Committee is
"independent" within the meaning of Rules 4200 and 4200A of the Marketplace
Rules of NASDAQ.


                        AUDIT COMMITTEE FINANCIAL EXPERT

     The Board of Directors of the Registrant has determined that the Registrant
has at least one audit committee financial expert (as defined in paragraph 8(b)
of General Instruction B to Form 40-F). The name of the audit committee
financial expert of the Registrant is Mr. Pierre MacDonald, the Audit
Committee's Chairman. The Commission has indicated that the designation of Mr.
MacDonald as the audit committee financial expert of the Registrant does not (i)
make Mr. MacDonald an "expert" for any purpose, including without limitation for
purposes of Section 11 of the Securities Act of 1933, as amended, as a result of
this designation; (ii) impose any duties, obligations or liability on Mr.
MacDonald that are greater than those imposed on him as a member of the Audit
Committee and the Board of Directors in the absence of such designation; or
(iii) affect the duties, obligations or liability of any other member of the
Audit Committee or the Board of Directors.


                                EXTERNAL AUDITORS

     PricewaterhouseCoopers LLP, Chartered Accountants, has acted as auditors of
the Registrant since the financial year ended December 31, 1993.

     In addition to performing the audit of the Registrant's consolidated
financial statements, PricewaterhouseCoopers LLP provided other services to the
Registrant and billed the Registrant the following fees for each of the
Registrant's two most recently completed financial years:


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<Table>
<Caption>
---------------------------------------------------------------------------------------------------------------------
                                                FINANCIAL YEAR ENDED                   FINANCIAL YEAR ENDED
                                                  DECEMBER 31, 2003                     DECEMBER 31, 2002
                 FEES                                    ($)                                   ($)
---------------------------------------------------------------------------------------------------------------------
<S>                                             <C>                                    <C>

Audit Fees(1)                                           333,329                                192,218
---------------------------------------------------------------------------------------------------------------------

Audit-Related Fees(2)                                     3,000                                  8,300
---------------------------------------------------------------------------------------------------------------------

Tax Fees(3)                                              45,616                                  8,475
---------------------------------------------------------------------------------------------------------------------

All other Fees(4)                                        60,850                                 16,207
---------------------------------------------------------------------------------------------------------------------

         TOTAL FEES:                                    442,795                                225,200
---------------------------------------------------------------------------------------------------------------------
ALL AMOUNTS ARE IN CANADIAN DOLLARS
---------------------------------------------------------------------------------------------------------------------
</Table>

(1)  Refers to all fees incurred in respect of audit services, being the
     professional services rendered by the Registrant's external auditor for the
     audit and review of the Registrant's financial statements as well as
     services normally provided by the external auditor in connection with
     statutory and regulatory filings and engagements.

(2)  Includes audit or attest services not required by statute or regulation,
     employee benefit plan audits, due diligence services, and accounting
     consultations on proposed transactions.

(3)  Incurred in respect of tax compliance, tax planning and tax advice.

(4)  Refers to all fees not included in audit fees, audit-related fees or tax
     fees.


                      PRE-APPROVAL POLICIES AND PROCEDURES

     The Registrant's Audit Committee is responsible for overseeing the work of
the independent auditors and has considered whether the provision of services
other than audit services is compatible with maintaining the auditors'
independence. The Audit Committee is determining which non-audit services the
external auditor are prohibited from providing and, exceptionally, approving and
overseeing the disclosure of permitted non-audit services to be performed by the
external auditor.

     For the year ended December 31, 2003, none of the services described above
were approved by the Audit Committee pursuant to paragraph (c)(7)(i)(C) of Rule
2-01 of Regulation S-X.


                         OFF-BALANCE SHEET ARRANGEMENTS

     There is no off-balance sheet arrangement as at December 31, 2003.


                DOCUMENTS FILED PURSUANT TO GENERAL INSTRUCTIONS

     In accordance with General Instruction D.(9) of Form 40-F, the Registrant
hereby files Exhibit 6 as set forth in the Exhibit Index attached hereto.


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                  UNDERTAKING AND CONSENT TO SERVICE OF PROCESS

A.   UNDERTAKING

          The Registrant undertakes to make available, in person or by
     telephone, representatives to respond to inquiries made by the Commission
     staff, and to furnish promptly, when requested to do so by the Commission
     staff, information relating to: the securities registered pursuant to Form
     40-F; the securities in relation to which the obligation to file an annual
     report on Form 40-F arises; or transactions in said securities.

B.   CONSENT TO SERVICE OF PROCESS

          The Registrant has previously filed with the Commission a written
     consent to service of process and power of attorney on Form F-X.


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                                   SIGNATURES


     Pursuant to the requirements of the Exchange Act, the Registrant certifies
that it meets all of the requirements for filing on Form 40-F and has duly
caused this Amendment No. 1 to the Annual Report to be signed on its behalf by
the undersigned, thereto duly authorized.



                                     AETERNA ZENTARIS INC.
                                     (formerly named AEterna Laboratories Inc.)



Date: October 22, 2004           By: /s/ Mario Paradis
                                     ----------------------------------------
                                     Name:  Mario Paradis
                                     Title: Senior Finance Director
                                            and Corporate Secretary


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                                  EXHIBIT INDEX

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<Caption>
EXHIBIT NUMBER                                  DOCUMENT                                   PAGE NO.
--------------                                  --------                                   --------
<S>                <C>                                                                     <C>
      1            Annual Information Form of Registrant, dated May 14, 2004, for
                            the year ended December 31, 2003

      2            Report of Independent Auditors

      3            Audited Consolidated Balance Sheets of Registrant, including the
                            Notes thereto, as at December 31, 2003 and 2002 and
                            Audited Consolidated Statements of Deficit, Consolidated
                            Statements of Contributed Surplus, Consolidated
                            Statements of Operations and Consolidated Statements of
                            Cash Flows for the years ended December 31, 2003, 2002
                            and 2001

      4            Annual Report of the Registrant for the year ended December 31,
                            2003

      5            Management's Discussion and Analysis of Financial Condition and
                            Results of Operations for the financial year ended
                            December 31, 2003

      6            Consent of Independent Accountants

      7            Code of Ethical Conduct

     31.1          Certification of the Chief Executive Officer pursuant to
                            Section 302 of Sarbanes-Oxley Act of 2002

     31.2          Certification of the Chief Financial Officer pursuant to
                            Section 302 of Sarbanes-Oxley Act of 2002

     32.1          Certification of the Chief Executive Officer pursuant to
                            Section 906 of Sarbanes-Oxley Act of 2002

     32.2          Certification of the Chief Financial Officer pursuant to
                            Section 906 of Sarbanes-Oxley Act of 2002
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