OSI Pharmaceuticals, Inc received notification from the US Patent and Trademark Office (PTO) that an initial office action has been issued regarding OSI's application for a reissue of the company's composition of matter patent for Tarceva (erlotinib), US Patent No 5,747,498 (the '498 patent). The office action includes an indication of allowability to composition of matter claims, including a claim specifically directed to Tarceva, while initially rejecting certain other claims. A rejection of some claims in an initial office action is not unusual in a patent reissue application proceeding.

"We are pleased with the indication of allowability of Tarceva-specific composition of matter claims and intend to respond to the rejection of the remaining claims," stated Colin Goddard, chief executive officer of OSI Pharmaceuticals. "We are encouraged by the PTO's response and are optimistic that this first step will allow us to have the reissue process substantially completed by the end of 2009."

The '498 patent is one of three OSI patents covering Tarceva (erlotinib). All three Tarceva patents, the '498 patent, US Patent No 6,900,221 and the US Patent No 7,087,613, remain listed in the Orange Book with the FDA and are enforceable against any infringer.

In February 2008, OSI filed with the US Patent and Trademark Office an application to reissue U.S. Patent No. 5,747,498 in order to correct certain errors relating to the claiming of compounds, other than Tarceva, which fall outside of the scope of the main claim in the patent. OSI's reissue application looked to correct these errors by deleting surplus compounds from the claims. Like most composition of matter patents, the '498 patent claims many compounds in addition to Tarceva. Tarceva itself is accurately described in the '498 patent.

OSI Pharmaceuticals is committed to "shaping medicine and changing lives" by discovering, developing and commercializing high-quality and novel pharmaceutical products designed to extend life and/or improve the quality of life for patients with cancer and diabetes/obesity.