Exhibit 31.1

    Certification Pursuant to Section 302 of the Sarbanes-Oxley Act of 2002


I, Garo H. Armen, certify that:

1.    I have reviewed this quarterly report on Form 10-Q of Antigenics Inc.;

2.    Based on my knowledge, this quarterly report does not contain any untrue
      statement of a material fact or omit to state a material fact necessary to
      make the statements made, in light of the circumstances under which such
      statements were made, not misleading with respect to the period covered by
      this report;

3.    Based on my knowledge, the financial statements, and other financial
      information included in this report, fairly present in all material
      respects the financial condition, results of operations and cash flows of
      the registrant as of, and for, the periods presented in this report;

4.    I am responsible for establishing and maintaining disclosure controls and
      procedures (as defined in Exchange Act Rules 13a-15(e) and 15d-15(e)) for
      the registrant and have:

       a)   Designed such disclosure controls and procedures, or caused such
            disclosure controls and procedures to be designed under my
            supervision, to ensure that material information relating to the
            registrant, including its consolidated subsidiaries, is made known
            to me by others within those entities, particularly during the
            period in which this quarterly report is being prepared;

       b)   Evaluated the effectiveness of the registrant's disclosure controls
            and procedures and presented in this quarterly report my conclusions
            about the effectiveness of the disclosure controls and procedures as
            of the end of the period covered by this quarterly report based on
            such evaluation; and

       c)   Disclosed in this quarterly report any change in the registrant's
            internal control over financial reporting that occurred during the
            registrant's most recent fiscal quarter (the registrant's fourth
            fiscal quarter in the case of an annual report) that has materially
            affected, or is reasonably likely to materially affect, the
            registrant's internal control over financial reporting: and

5.    I have disclosed, based on my most recent evaluation of internal control
      over financial reporting, to the registrant's auditors and the audit
      committee of registrant's board of directors (or persons performing the
      equivalent functions):

       a)   All significant deficiencies and material weaknesses in the design
            or operation of internal control over financial reporting which are
            reasonably likely to adversely affect the registrant's ability to
            record, process, summarize and report financial information; and

       b)   Any fraud, whether or not material, that involves management or
            other employees who have a significant role in the registrant's
            internal control over financial reporting.



Date:   August 9, 2004                      /s/ Garo H. Armen
                                            ----------------------------------
                                            Garo H. Armen Ph.D., Chairman, and
                                            Chief Executive Officer
                                            (Principal Accounting Officer)