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Court of Appeal Upholds Promised Utility Of Iron Chelation Patent

On September 15, 2016 the Court of Appeal dismissed Teva’s appeal Justice O’Reilly’s prohibition Order preventing the Minister of Health from approving Teva’s deferasirox product until the expiry of Canadian Patent No. 2,255,951 (see our previous post here).

The only issue on the appeal was the construction of the promise of the patent, and specifically whether the following “key passage”, the only statement related to the utility of the “formula II” compounds, promised the compounds were useful in human therapy:

It has now been found that certain substituted 3,5-diphenyl-1,2,4-triazoles have valuable pharmacological properties when used in the treatment of disorders which cause an excess of metal in the human or animal body or are caused by it, primarily a marked binding of trivalent metal ions, in particular those of iron.

The Court of Appeal agreed that the Applications Judge erred by considering the abstract in construing the promise, but that this error was not material. Other than the “key passage”, all other statement in the patnet were directed to the formula I compounds. The Court of Appeal rejected Teva’s argument that since all formula II compounds were also formula I compounds, that statements of use of formula I compounds also apply to the claimed  formula II compounds:

 [23] In my view, this argument ignores the fact that at law different claims can have different utilities for the same compound (see, for example, Apotex Inc. v. Pfizer Canada Inc., 2014 FCA 250, 465 N.R. 306 (Celebrex); Teva Canada Limited v. Novartis AG, 2013 FC 141, 109 C.P.R. (4th) 1 (Imatinib)).

[24] Given the manner in which the patent differentiates between the formula I and II compounds (particularly in the disclosure and in claims 1 and 5) the statements of use at the bottom of page 2 through to page 10 of the disclosure can only relate to claims 1 to 4. They cannot relate to the novel compounds (claims 5 to 37).

The Court of Appeal held that the Applications Judge was correct to rely on claim differentiation in construing the promised utility of the 951 Patent:

[25] The Federal Court’s construction of the promise of the patent was consistent with differentiation contained in the disclosure and the claims. It is also consistent with the useful advance over the prior art described in the patent. The Federal Court’s construction was correct

[28] I also reject the argument that the Federal Court erred by applying “claim differentiation” to construe the promise of the novel formula II compounds claims to be different from the promise of the formula I use claims. For the above reasons, the Federal Court was correct to differentiate between the compounds and use claims.

Since Novartis had demonstrated or could soundly predict the utility of the claimed compounds, the Court of Appeal held that the Applications Judge was correct to hold that Teva’s allegation of invalidity was not justified.

A copy of the Court of Appeal’s Reasons may be found here.

Teva was represented by Aitken Klee on the appeal.