Exhibit 23.1 CONSENT OF INDEPENDENT PUBLIC ACCOUNTANTS To Cell Pathways, Inc.: As independent public accountants, we hereby consent to the incorporation by reference in this registration statement of our report dated February 25, 2002 included in Cell Pathways, Inc.'s Form 10-K for the year ended December 31, 2001 and to all references to our Firm included in this registration statement. /s/ Arthur Andersen LLP Philadelphia, Pennsylvania April 9, 2002