The Federal Court of Appeal has upheld Pfizer’s VIAGRA patent by applying the new Canadian test for obviousness true to its formulation by the Supreme Court of Canada in Sanofi v. Apotex, 2008 SCC 61. In Pfizer v. Apotex, 2009 FCA 9, the Court of Appeal distinguished the test as formulated in Canada from a more extreme version applied in the UK which led to the invalidation of Pfizer’s UK counterpart VIAGRA patent.

In Sanofi, the Supreme Court adopted the English “obvious to try” test, but cautioned it is not a panacea for infringers and would only invalidate where it was more or less self-evident what was being tested ought to work. The caveat was put to the test before the Court of Appeal in the VIAGRA case, but held up well. It rejected outright the proposition that an invention can be obvious to try where expectations of success are uncertain or slim because there is strong motivation due to the high rewards of potential success. It was confirmed that the Canadian test does not involve a balancing of expected rewards versus risk of failure as has been applied in the UK.

This is the Federal Court of Appeal’s first reported application of the new Canadian obviousness test, which confirms that in substance there has not been much change over the prior test. As a result, the Court of Appeal upheld the decision at first instance, which found the Pfizer patent to be valid under the former Canadian obviousness test.