In its first decision to consider the Supreme Court of Canada’s landmark decision in AstraZeneca Canada Inc v Apotex Inc, 2017 SCC 36 [Esomeprazole](see our article here) on the utility requirement, the Federal Court of Appeal has overturned a finding of inutility made under the promise doctrine, with practical guidance for the requirement of a scintilla of utility: Bristol-Myers Squibb v Apotex, 2017 FCA 190.

Applications Judge – inutility due to failure to meet promise

The compound dasatinib is sold by Bristol-Myers Squibb (BMS) as SPRYCEL, a drug used in the treatment of chronic myelogenous leukemia (CML).  In a prohibition application under the Patented Medicines (Notice of Compliance) Regulations, Apotex alleged that a bare claim for the compound – claim 27 of Canadian Patent No. 2,366,932 (the 932 patent) – was invalid for lack of utility. 

Applying the “promise” analytical framework, before the release of Esomeprazole, the Federal Court found that there was an overarching promise in the 932 patent that dasatinib will “1) inhibit a Src-family PTK; 2) inhibit HER1 and HER2; and 3) be useful to treat a PTK-associated disorder or useful as anti-angiogenic agents.”  The Federal Court found that BMS had data to show (1) but not (2) or (3).  The Federal Court thus concluded that BMS had not met their burden to show that the entire overarching promised utility was either demonstrated or soundly predicted at the relevant date.

FCA – dasatinib’s inhibition of certain enzymes meets the utility requirement 

Following Esomeprazole, the Federal Court of Appeal reversed.  The Court first noted that in Esomeprazole, in a unanimous decision, the Supreme Court abolished the promise doctrine.  The Court then applied the Supreme Court’s two-step test for utility. 

First, determining the subject-matter of the claim, the Federal Court of Appeal held that the subject-matter of claim 27 was merely the compound, and not the potential therapeutic uses for dasatinib. 

Second, determining whether this subject-matter was shown to be useful either by demonstration or sound prediction as of the filing date, the Federal Court of Appeal found that BMS had demonstrated utility as it was conceded that BMS had demonstrated that dasatinib acted to inhibit Src-family PTKs.

As to the sort of discovery that will give rise to a scintilla of usefulness, the Federal Court of Appeal rejected Apotex’s argument that demonstration of “binding of dasatinib to certain isolated enzymes in a test tube” cannot satisfy the utility requirement:

[40] I disagree.  Establishing that a compound has the ability to inhibit a biological target implicated in disease is doubtlessly a useful discovery. Here, it was known as of the relevant date that enhanced activity of PTK was involved in many diseases, as stated in the specification and confirmed in the evidence of several of the experts. Thus, discovery of a substance that acted to inhibit certain PTKs represented an important advance and certainly meets the minimal utility requirements that are now applicable following the decision of the Supreme Court in Esomeprazole.

Disposition

The Federal Court of Appeal set aside the judgment below in respect of the 932 patent and issued an order prohibiting issuance of a notice of compliance to Apotex for its dasatinib product until the expiry of the 932 patent. 

The Federal Court of Appeal dismissed BMS’s appeal regarding a second patent, Canadian Patent No. 2,519,898, containing claims to the oral use of dasatinib for treatment of CML and imatinib-resistant CML.The Court of Appeal found no error in the Federal Court’s finding that Apotex’s obviousness allegation was justified.