MELVILLE, N.Y.--(BUSINESS WIRE)--OSI Pharmaceuticals, Inc. (Nasdaq: OSIP) announced today that its 2.0% Convertible Senior Notes due 2025 (the “notes”) are now convertible at the option of the holders and will remain convertible through December 29, 2006, the last trading day of the current fiscal quarter, as provided for in the Indenture governing the notes.