OSI Pharmaceuticals to Announce Fourth Quarter and Year-End 2009 Financial Results on February 23, 2010

OSI Pharmaceuticals, Inc. (Nasdaq: OSIP) announced today that its fourth quarter and year-end 2009 financial results will be released on February 23, 2010, after the markets close. Following the announcement, OSI’s management will host a live conference call and webcast at 5:00 p.m. Eastern Time to review the Company’s financial results, product portfolio and business developments.

To access the live webcast or the archive via the Internet, log on to www.osip.com. Please connect to the Company's website at least 15 minutes prior to the conference call to ensure adequate time for any software download that may be needed to access the webcast. Alternatively, please call 1-877-329-7568 (U.S.) or 1-719-325-2137 (international) to listen to the call. The conference ID number for the live call is 8291684. Telephone replay is available approximately two hours after the call. To access the replay, please call 1-888-203-1112 (U.S.) or 1-719-457-0820 (international). The conference ID number for the replay is 8291684.

About OSI Pharmaceuticals

OSI Pharmaceuticals is committed to "shaping medicine and changing lives" by discovering, developing and commercializing high-quality, novel and differentiated targeted medicines designed to extend life and improve the quality of life for patients with cancer and diabetes/obesity. For additional information about OSI, please visit http://www.osip.com.