EXHIBIT 99.2

     Pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, I, the
undersigned Chief Executive Officer of Antigenics Inc. (the "Company"), hereby
certify that the Annual Report on Form 10-K of the Company for the year ended
December 31, 2002 (the "Report") fully complies with the requirements of
Section 13(a) or 15(d) of the Securities Exchange Act of 1934 and that
information contained in the Report fairly presents, in all material respects,
the financial condition and results of operations of the Company.

                                        /s/ Garo H. Armen, Ph.D.
                                        ------------------------
                                        Garo H. Armen, Ph.D.
                                        Chairman and Chief Executive Officer

Date: March 26,2003

A signed original of this written statement required by Section 906 has been
provided to Antigenics Inc. and will be retained by Antigenics Inc. and
furnished to the Securities and Exchange Commission or its staff upon request.

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