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Exhibit 8

CODE OF ETHICAL CONDUCT
Æterna Zentaris Inc. ("Æterna Zentaris") and all of the directors, officers and employees of Æterna Zentaris and its subsidiaries (collectively with Æterna Zentaris, the "Company") are committed to preserving the reputation of the Company for integrity and excellence and conducting the businesses and activities of the Company honestly and ethically and in compliance with applicable laws, rules and regulations.
Accordingly, the Board of Directors of Æterna Zentaris has adopted this Code of Ethical Conduct, which applies to all directors, officers and employees of the Company and its subsidiaries, including, but not limited to, Æterna Zentaris' principal executive officer, principal financial officer, principal accounting officer or controller and persons performing similar functions. This Code of Ethical Conduct is intended to meet the requirements for a code of ethics under the Sarbanes-Oxley Act of 2002 (and the related regulations adopted by the Securities and Exchange Commission) and the applicable Marketplace Rules of The Nasdaq Stock Market, Inc.
This Code of Ethical Conduct does not summarize all of the Company's policies. You must also comply with the Company's other policies which are set forth elsewhere. In addition, this Code of Ethical Conduct reflects general principles of conduct and does not anticipate or cover in detail every topic or situation. If you have a question about anything covered in this Code of Ethical Conduct or if you are unsure about whether some action would be consistent with this Code of Ethical Conduct, you agree to ask the Head of Legal Affairs of Zentaris GmbH or the Vice President, Legal Affairs of Atrium Biotechnologies Inc. (the "Subsidiaries Legal Department") or the Corporate Secretary of Æterna Zentaris (the "Compliance Officer"). Similarly, if you should encounter a situation in which you are unsure what to do, you agree to tell the Subsidiaries Legal Department or the Compliance Officer and ask for help.
Policies and Practice
General Conduct — Conflicts of Interest
You should act ethically, honestly and with integrity. Your duty to act ethically, honestly and with integrity includes avoiding actual or apparent conflicts of interest between your personal, private interests and the interests of the Company, including using your position to receive improper personal benefits. This obligation applies to both business relationships and personal activities. A "conflict of interest" exists whenever your interests (financial or otherwise) interfere or conflict in any way (or even appear to interfere or conflict) with the Company's interests. A conflict of interest can arise when you take actions or have interests that may make it difficult to perform your work for the Company objectively and effectively. Conflicts of interest may also arise when you, or members of your family, receive improper personal benefits as a result of your position with the Company, regardless of from where those benefits are received.
You also owe the Company a duty to advance its legitimate interests when the opportunity to do so arises. You are prohibited from (i) taking for yourself personally opportunities that properly belong to the Company or are discovered through the use of the Company's resources, property, information or your position with the Company; (ii) using corporate property, information (confidential or otherwise) or position for personal gain; or (iii) competing with the Company. You should conduct your personal affairs so that there can be no unfavorable reflection on the Company, either express or implied. You must report to the Subsidiaries Legal Department or the Compliance Officer any interest or relationship that you believe might compromise or appear to compromise your duty of loyalty to the Company or otherwise might present conflict of interest concerns. In addition, if you become aware of any conflict of interest on the part of anyone else at the Company, you must report it to the Subsidiaries Legal Department or the Compliance Officer. Each such Subsidiaries Legal Department shall then report such matter to the Compliance Officer.
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Compliance with Laws, Rules and Regulations
In performing your duties on behalf of the Company, you must comply with all applicable governmental laws, rules and regulations, as well as the rules and regulations of any stock exchanges and quotation systems on which Æterna Zentaris' securities are listed.
Public Disclosure — Confidentiality of Non-Public Information
As a public company, Æterna Zentaris must provide full, fair, accurate, timely, and understandable disclosure in reports and documents that Æterna Zentaris files with, or submits to, the Securities and Exchange Commission or other regulators and in other public communications by Æterna Zentaris.
Consequently, the Company's books, business records, accounts and financial statements must be maintained in reasonable detail, must appropriately reflect the Company's transactions and must conform both to applicable legal and regulatory requirements, including, if applicable, maintaining the financial and accounting records in accordance with generally accepted accounting principles, and to the Company's system of internal controls. Unrecorded or "off the books" funds or assets should not be maintained unless permitted by applicable law or regulation.
In addition, all employees, officers and directors of the Company are expected to comply with the Company's disclosure controls and procedures to ensure that material information relating to the Company is timely recorded, processed, summarized and reported in accordance with all applicable laws, rules and regulations. You must ensure that all information or data that you report to management is accurate and honest, and you must fully and accurately comply with all audits, requests for special record keeping or retention of documents, documents or other material from or on behalf of the Company's auditors or the Company's management.
You must also take all reasonable measures to protect the confidentiality of non-public information about the Company and its customers obtained or created in connection with your activities and prevent the unauthorized disclosure of such information unless required by applicable law or regulation or legal or regulatory process.
Compliance with this Code of Ethical Conduct
All employees, officers and directors of the Company, regardless of level or seniority in the Company, have a duty to review, understand and adhere strictly to the guidelines set forth in this Code of Ethical Conduct.
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The Company is committed to holding all employees, officers and directors accountable for adherence to this Code of Ethical Conduct.
Duty to Report Violations of this Code of Ethical Conduct — No Retaliation
If you reasonably believe that anyone connected with the Company may have, or is about to, materially violate this Code of Ethical Conduct, you must promptly bring the matter to the attention of the Subsidiaries Legal Department or the Compliance Officer. Each such Subsidiaries Legal Department shall then report such matter to the Compliance Officer. If you do not believe that talking to the Subsidiaries Legal Department or the Compliance Officer is appropriate or if it does not result in a response with which you are comfortable, then you should contact any of Æterna Zentaris' executive officers or any member of Æterna Zentaris' Board of Directors. If requested, the Company will keep your name confidential except as required by applicable law.
If you have questions or concerns regarding accounting or auditing matters, then, in addition to the reporting procedures described above, you may also confidentially and anonymously submit such questions or concerns to the Audit Committee of the Board of Directors of Æterna Zentaris.
The Company will not tolerate retaliation of any kind against any person whom in good faith reports to the Company potential issues relating to violations of this Code of Ethical Conduct. Any director, officer or employee of the Company who commits such retaliation will be subject to disciplinary measures. If you believe that you have been penalized, discharged, disciplined or otherwise penalized for reporting a violation in good faith, you should immediately report that belief in accordance with the reporting procedures described above.
Disciplinary Actions
The Company is committed to the appropriate, prompt investigation and follow-up of any violation or suspected violation of this Code of Ethical Conduct. Reports of violations will be investigated under the Compliance Officer's supervision, in such manner as the Compliance Officer finds appropriate. You are expected to cooperate in the investigation of reported violations. The Compliance Officer has the power to monitor, make determinations, and recommend action to the Board of Directors of Æterna Zentaris with respect to violations of this Code of Ethical Conduct.
As far as legally possible, violations of this Code of Ethical Conduct may result in disciplinary measures, including, depending on the individual circumstances, the level of involvement and knowledge and the severity of the violation, (i) warning and/or reprimand; (ii) demotion; or (iii) termination of the employment.
In addition, violations of this Code of Ethical Conduct may also constitute violations of law and may result in civil and criminal penalties for you, your supervisors and/or the Company.
Waivers of any Provision of this Code of Ethical Conduct
Any request for a waiver of any provision of this Code of Ethical Conduct for a director, officer or employee of the Company must be in writing and addressed to the Compliance Officer. The Board of Directors of Æterna Zentaris must approve any waiver with respect to this Code of Ethical Conduct that involves a director or an executive officer of Æterna Zentaris. Waivers of any provision of this Code of Ethical Conduct for an officer or employee of the Company (other than a person who is a director or executive officer of Æterna Zentaris) may be made by the Compliance Officer.
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Æterna Zentaris is required to publicly disclose any waivers granted to a director or executive officer of Æterna Zentaris, along with the reasons for such waivers, in accordance with the provisions of the Securities Exchange Act of 1934, as amended, and the relevant rules, if any, of any stock exchanges and quotation systems on which Æterna Zentaris' securities are listed.
Amendments to this Code of Ethical Conduct
The Board of Directors of Æterna Zentaris may update or otherwise amend this Code of Ethical Conduct. When there are material changes, the Company will provide each director, officer and employee of the Company with an updated copy of the Code of Ethical Conduct.
Adopted and approved by the Board of Directors on March 29, 2004 and amended by the Board of Directors on November 3, 2004.
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Exhibit 8CODE OF ETHICAL CONDUCT