Monday, February 11, 2013

Pfizer Canada Inc. v. Pharmascience Inc., 2013 FC 120

Monday, February 11, 2013

Last week, the Federal Court released its decision to dismiss an application brought under the provisions of the Patented Medicines (Notice of Compliance) Regulations (PM(NOC) Regulations) to prohibit the issuance of a Notice of Compliance to Pharmascience Inc. (Pharmascience) in respect of its PMS-Pregabalin capsules until the expiry of Canadian Patent No. 2,255,652 ('652 patent).

Pfizer Canada Inc. had obtained a Notice of Compliance to sell tablets containing pregabalin under the brand name LYRICA, and had listed the ‘652 patent in accordance with the PM(NOC) Regulations.

Pharmascience, in a Notice of Allegation, alleged that claims 4, 6-12, 14 and 15 of the ‘652 patent would not be infringed by its product, and that the patent is invalid on the grounds of, among other reasons, inutility, lack of sound prediction, and claiming broader than the invention made or disclosed. 

Only claim 3 of the '652 patent was at issue in the present decision.  Claim 3 was construed as follows:

3. For use in treating pain, in a mammal, a therapeutically effective amount of a compound which is (S)-3-(aminomethyl)-5-methylhexanoic acid or 3-aminomethyl-5-methyl-hexanoic acid (its racemate).

Justice Hughes further construed the term “pain” as used in claim 3 to include all of the specific pains listed in claims 4 to 16 and on pages 1 and 5 of the ‘652 patent, which includes examples of both chronic and acute pain. 

As a result of this construction, and in part due to evidence provided by the inventor by way of affidavit, indicating that his objective was to test pregabalin only for chronic or persistent pain, Hughes J stated in paragraph [93]:

The evidence shows, therefore, that the inventor never tested or contemplated the testing of the racemate. The inventor stated that pregabalin is useful only in respect of chronic or persistent pain, not acute pain.

Hughes J found that claim 3 was broader in scope than the invention made or disclosed, and therefore invalid.

Hughes J also considered the utility of claim 3.  In this regard, he found claim 3 to be invalid as it “embraces pain which cannot be treated, as well as pain which ... could not have been predicted as treatable by pregabalin.” 

Hughes J also found that, since the ‘652 patent did not provide any evidence that the racemate was useful in treating pain (or that it had been tested at all), there was no factual basis or line of reasoning to soundly predict that the racemate would be useful in treating the “variety of pain encompassed by claim 3 or even some of them” (paragraph [184]).

Hughes J therefore found that claim 3 was also invalid due to inutility and lack of sound prediction.

The full decision can be found at the following link: