Teva Canada Ltd v Novartis AG / imatinib 2013 FC 141, Snider J
GLEEVEC / imatinib mesylate / 2,093,203
Imatinib has proven to be a revolutionary treatment for chronic myeloid leukemia: “What once was a death sentence has now become a manageable chronic illness with overall survival rates equal to the general population” . The ‘203 patent includes a compound claim to imatinib (Claim 29) and a claim to the use of imatinib for the treatment of tumours (Claim 46, read together with Claim 29) . These were the key claims at issue, and both were held to be valid. (Other important claims included Claim 1, the broadest genus claim, which was held to be invalid, and Claim 5, a sub-genus claim encompassing imatinib, which was held to be valid. A number of other claims to individual compounds were also held to be valid.)
As is now standard with respect to pharmaceutical patents, the main attack on the patent was based on lack of utility , and a key argument turned on the promise of the patent. In the end, Snider J construed the promise modestly, in favour of the patentee, but her decision illustrates once again that under the false promise doctrine, validity of a pharmaceutical patent may turn on an extraordinarily fine parsing of the description. Whatever the result, this is problematic, as the description is intended to disclose the invention, not to define it; the false promise doctrine means that the same meticulous care that must be given to every word of the claims, should also be given to every word of the description when drafting a Canadian patent application.