Cell Pathways' Aptosyn™ (exisulind) shows continuing long-term prevention of colon polyps in FA...( Results of Phase III Trial and Exte...),Health

Results of Phase III Trial and Extension Study Data Presented by Cleveland Clinic Investigator at American Gastroenterological Association Meeting

Clinical results from familial adenomatous polyposis (FAP) patients treated with Aptosyn™(exisulind) for up to 18 months were presented today at the annual meeting of the American Gastroenterological Association (AGA) by Carol Burke, M.D. of the Cleveland Clinic Foundation. Results of a one year double-blinded, placebo-controlled Phase III trial and its six month open-label extension, sponsored by Cell Pathways, Inc. (Nasdaq: CLPA), demonstrate that Aptosyn™ induces a clinically significant reduction in the formation of precancerous colon polyps in patients with FAP after as little as six months of therapy. Moreover, patients who have continued on Aptosyn™ for more than one year continue to show further improvement over time.

In a separate release the company announced the presentation of preclinical research being presented at AGA showing that colonic tumor cells marked by hereditary defects different from the APC gene mutation that characterizes FAP also undergo apoptosis, or programmed cell death, when treated with Aptosyn. The company also reported laboratory findings that the cyclic GMP phosphodiesterase targeted by Aptosyn™ and other selective apoptotic antineoplastic drugs (SAANDs) is over-expressed in colonic neoplasias relative to normal colonic mucosal tissue. This observation may explain in part the selectivity of SAANDs for precancerous and cancerous cells and not for normal tissue.

Results of Phase III Trial and Extension Study

"Based on the clinical responses that we have observed to date, use of exisulind for the chemoprevention of colonic adenomas has the potential to significantly alter the management of patients with FAP," commented Dr. Burke, a principal investigator for the Phase III study and for the previous Phase II trial of Aptosyn&
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22-May-2000