Federal Court Invalidates Janssen ZYTIGA' Patent

• Published date: 21 January 2021
• Subject Matter: Intellectual Property, Patent
• Law Firm: Bereskin & Parr LLP
• Author: Ms Shuo Xing, Melanie Szweras and R. Scott MacKendrick

On January 14, 2021, the Federal Court issued a decision (Janssen Inc. et al v. Apotex Inc. et al, 2021 FC 7) in the consolidated infringement action brought under s. 6(1) of the Patented Medicine (Notice of Compliance) (PM(NOC)) Regulations by Janssen against Apotex, Dr. Reddy's Laboratory, and Pharmascience. In this decision, the Court invalidated the asserted claims of Janssen's Canadian Patent 2,661,422 (the 422 Patent), which claimed the combined use of the two active ingredients found in Janssen's brand name drug ZYTIGA, abiraterone acetate and prednisone, in the treatment of prostate cancer. Concurrently, the Court dealt with Apotex' counterclaim under s. 6(3) of the PM(NOC) Regulations to invalidate the asserted and non-asserted claims of the 422 Patent. This decision provides important lessons and reminders in drafting and prosecuting patent applications relating to use of therapeutic agents in the treatment of diseases.

Although the 422 Patent had been the focus in earlier proceedings under the previous PM(NOC) Regulations, this action was brought under the current PM(NOC) regime. As such, the parties were able to advance new and more comprehensive evidence and the previous expert witnesses were open to examination. At the same time, the Court was required to approach this infringement action afresh with 'a mind willing to understand and be persuaded'.¹ As a result, despite prohibiting the Minister of Health from issuing a NOC to Apotex in its 2019 decision (2019 FC 1355), the Court arrived at the opposite conclusion and found the asserted claims of the 422 Patent to be invalid for obviousness. The 2019 NOC decision is currently pending appeal.

A representative asserted claim of the 422 Patent, claim 3, is directed at '[u]se of a therapeutically effectively amount of abiraterone acetate and a therapeutically effective amount of prednisone in the treatment of a prostate cancer in a human'. In construing the asserted claims, there was little contention around the identity of the person of ordinary skill in the art or the citability of the prior art documents.

In following the principles of claim construction laid out in Whirlpool v Camco (2000 SCC 67) and Free World Trust v Électro Santé (2000 SCC 66), the Court looked closely to the definitions provided by the patentee in the description of the 422 Patent. Since the asserted claims of the 422 Patent refer to individual therapeutically effective amounts of abiraterone acetate and prednisone, the...