FCA Confirms Entirety Of Inventors' Conduct Is Relevant In Obviousness Analysis And Upholds Inventiveness Of Crystal Form Patent

The Federal Court of Appeal ("FCA") upheld the validity of Canadian Patent 2,436,668 ("668 Patent") which covers Form I ODV succinate (marketed as PRISTIQ) in two separate appeals by Apotex Inc. ("Apotex") and Teva Canada Ltd ("Teva"), finding that the claims were novel and inventive.

Obviousness

The FCA began be reiterating key points of the obviousness analysis:

The Sanofi test is flexible and expansive and can include consideration of the invention story as a whole; The "obvious to try" test is only one part of the obviousness analysis and does not displace other tests, including the test set out in Beloit Canada Ltd. v. Valmet Oy, (1986), 64 N.R. 287, 8 C.P.R. (3d) 289 (F.C.A.), i.e., whether the skilled person would have come "directly and without difficulty" to the solution taught by the patent; From this framework, the FCA found that the claims of the 668 Patent were inventive, focusing on the Federal Court's findings that:

None of the crystal forms of ODV succinate had ever been made, disclosed, or characterized; it was impossible to predict whether or how ODV succinate could be made; there was a lack motivation to form ODV succinate because past experiments with ODV fumerate (another salt of ODV) had failed (it had poor bioavailability); and many experiments were required to produce the crystal form. In both appeals, the FCA rejected arguments that the claims were "obvious to try" in light of Bristol-Myers Squibb Canada Co. v. Teva Canada Limited, 2017 FCA 76 (Atazanavir) and Pfizer Limited v. Ratiopharm Inc., 2010 FCA 204 (Amlodipine), which cases related to salts. The FCA noted that there was evidence in Atazanavir and Amlodipine that the salts in issue had already been shown to offer stability advantages and improved pharmaceutical properties. By contrast, salts of ODV succinate would have not have been expected to work because the ODV fumerate salt had not worked.

In the Apotex appeal, the FCA rejected Apotex's argument that experiments unrelated to the salt screens for ODV succinate, such as prior experiments with pro-drugs and with ODV fumerate should be excluded from consideration because they were efforts "in other directions". The FCA disagreed and confirmed that it the entirety of the inventors' course of conduct could be considered including other directions and approaches taken to solving the problem.

Similarly, the FCA also rejected Apotex's argument that tests that occurred after the ODV succinate crystal was...