The Federal Court of Appeal (FCA) has dismissed an appeal concerning four actions related to the molecule apixaban under the Patented Medicines (Notice of Compliance) Regulations (Regulations). The Federal Court (FC) found the patents at issue to be valid.
Bristol-Myers Squibb Canada Co. (BMS) markets ELIQUIS® (apixaban) in Canada for the treatment of thrombosis. ELIQUIS® inhibits the enzyme Factor Xa (FXa). Canadian Patent Nos. 2,461,202 (202 Patent) and 2,791,171 (171 Patent) are listed on the patent register against ELIQUIS®. As we reported, BMS successfully asserted these patents against PMS in an infringement action under the Regulations. On appeal, PMS challenged the trial decision on a number of grounds relating to patent invalidity.
Validity of 202 Patent upheld
Selection Patent. The FCA affirmed that the 202 Patent met the requirements for a selection patent.
Apixaban was part of the genus of compounds disclosed in the earlier Canadian Patent No. 2,349,330 (330 Patent). PMS argued the FC did not make a clear finding related to the status of the 202 Patent as a selection patent, including that the 202 Patent did not disclose a special advantage.
The special advantage that apixaban was useful in treating thromboembolic disorders would not have been true of the entire genus in the 330 Patent. The FCA held that in reaching this conclusion, the Trial Judge was entitled to (i) consider the claims in determining how a skilled person would understand the 202 Patent as a whole; and (ii) find that a special advantage was disclosed by inference. An explicit comparison of apixaban to any other compound of the 330 Patent was not required.
Insufficiency. The FCA affirmed that the 202 Patent was not invalid for insufficient disclosure.
PMS argued that the FC erred by assessing insufficiency based on the patent as it read at the date of issuance, rather than the date of filing or publication. The FCA rejected this argument. As with other issues such as construction, anticipation, obviousness, and inutility, the insufficiency analysis should be based on the issued patent even if the relevant date is earlier.
In this case, PMS argued that the date was significant because the 202 Patent did not focus on apixaban at filing and at publication. Claims specific to apixaban were not added until shortly before the patent issued. The FCA noted the “real debate” in this regard was not insufficiency, but whether the new claims complied with the rules regarding added matter. Although this issue was not raised at trial, the FCA expressed the view that an example describing the synthesis of apixaban was sufficient to support the added claims.
Obviousness. The FCA affirmed that the 202 Patent was not obvious.
PMS argued that while the FC correctly identified the steps in the obviousness analysis, it erred in failing to address (i) the inventive concept and (ii) the difference between the state of the art and the inventive concept in its reasons.
The FCA found that the Trial Judge’s reasoning was understandable despite not addressing each step in the obviousness analysis. The inventive concept of the 202 Patent was the selection of apixaban; the difference between the inventive concept and the state of the art was that apixaban was an effective FXa inhibitor useful in treating thromboembolic disorders.
Validity of 171 Patent upheld
Obviousness: The FCA affirmed that the invention of the 171 Patent was not obvious to try.
The 171 Patent related to formulations of apixaban tablets. PMS argued that the FC erred in defining the obvious-to-try test, focussing on a paragraph of the trial judgment stating that “the ‘obvious to try’ test works only where it is very plain or more or less self-evident that what is being tested ought to work.” PMS argued the FC erred in treating this as a requirement rather than simply one factor to be considered.
The FCA rejected this argument, finding that the Trial Judge correctly quoted from the Supreme Court of Canada’s decision in Apotex Inc v Sanofi-Synthelabo Canada Inc, 2008 SCC 61. Furthermore, the Trial Judge addressed additional factors of the obvious-to-try analysis, albeit without identifying them as such.
The FCA also rejected a number of other arguments concerning obviousness, ambiguity, and overbreadth.
Links to decisions:
Trial decision: Bristol-Myers Squibb Canada Co v Pharmascience Inc, 2021 FC 1
Appeal decision: Pharmascience Inc v Bristol-Myers Squibb Canada Co, 2022 FCA 142