To: tom pope who wrote (256 ) 9/15/2005 10:05:33 AM From: tuck Respond to of 447 >>MELVILLE, N.Y.--(BUSINESS WIRE)--Sept. 15, 2005--OSI Pharmaceuticals, Inc. (NASDAQ: OSIP - News) announced today that (OSI) Prosidion, its UK subsidiary focused on the discovery and development of diabetes and obesity therapeutics, presented preclinical research data on its Dipeptidyl Peptidase IV (DPIV) inhibitor, PSN9301, during the European Association for the Study of Diabetes 41st Annual Meeting held from September 10th - 15th in Athens, Greece. PSN9301 is a novel oral DPIV inhibitor currently undergoing Phase II clinical trials where its efficacy and safety are being evaluated in type 2 diabetic patients. Effects of Dipeptidyl Peptidase IV Inhibitor PSN9301 and Metformin Alone and in Combination on Glucose Tolerance and Body Weight in the fa/fa Zucker Rat, and in a Polygenetic Rat Model of Diabetes, J.G. McCormack, Ph.D., D.Sc et al (Abstract #789) PSN9301's rapid onset, and relative short duration, of action facilitate an optimal meal-related dosing regimen, which may enhance the physiological gain from meal-related increases in incretin hormone levels (such as GLP-1) and reduce unwanted effects on other DPIV substrates between meals ("inter-prandial sparing"). Incretin hormones are secreted by specific cells located in the small intestine in response to food intake and act to stimulate insulin release. Researchers from OSI's diabetes and obesity subsidiary (OSI) Prosidion presented data assessing the acute and subchronic anti-diabetic efficacy of PSN9301 in both mono- and poly-genetic animal models in comparison to, and in combination with, Metformin. In the male diabetic fa/fa Zucker rat model as well as in the poly-genetic Diet-Induced-Obese (DIO) rat model, sub-chronic administration of PSN9301 increased blood glucose clearance to a similar degree to Metformin, and its combination with Metformin further improved glucose homeostasis compared to Metformin and PSN9301 alone. In the DIO rat PSN9301 in combination with Metformin was further able to reduce body weight gain over the two-week study period compared to Metformin and PSN9301 alone. The results of these studies indicate that the combined administration of PSN9301 plus Metformin may be a highly promising therapeutic approach especially in obese type 2 diabetics. "We believe that PSN9301 provides us with a differentiated and competitive agent in the DP-IV arena and we look forward to data from the Phase II PSN9301 study by the end of 2005," stated Anker Lundemose, M.D., Ph.D., President of (OSI) Prosidion. << snip Cheers, Tuck