LETTER 1 filename1.txt Via Facsimile and U.S. Mail Mail Stop 03-09 June 20, 2005 Mr. H. Ward Wolff Chief Financial Officer and Senior Vice President Abgenix, Inc. 6701 Kaiser Drive Fremont, CA 94555 Re: Abgenix, Inc. Form 10-K for the fiscal year ended December 31, 2004 File No. 000-24207 Dear Mr. Wolff: We have completed our review of your Form 10-K and related filings and have no further comments at this time. Sincerely, Joel Parker Accounting Branch Chief ?? ?? ?? ?? H. Ward Wolff Abgenix, Inc. Page 1