Federal Court of Canada Declares Idenix’s Hepatitis C Drug Patent Invalid and Upholds Gilead’s Sofosbuvir Compound Patent

On November 2, 2015, Annis J of the Federal Court of Canada issued his public judgment in Gilead Sciences, Inc v Idenix Pharmaceuticals, Inc, 2015 FC 1156, declaring Canadian Patent No 2,490,191 (191 Patent), co-owned by Idenix Pharmaceuticals, Inc (Idenix), invalid.  Annis J dismissed Idenix’s counterclaims for infringement of the 191 Patent by Gilead Pharmasset, Inc, Gilead Sciences, Inc, and Gilead Sciences Canada, Inc (together, Gilead) and seeking a declaration of invalidity of Gilead’s Canadian Patent No 2,527,657 (657 Patent).

The 191 and 657 Patents both relate to the compound sofosbuvir (Gilead’s SOVALDI®) for the treatment of Hepatitis C viral (HCV) infections.  Annis J found that sofosbuvir, including its metabolites, and a manufacturing intermediate, fell within the scope of the 191 Patent claims.

Idenix’s 191 Patent

Gilead initiated this action to invalidate the 191 Patent on the grounds of (i) inutility (lack of demonstrated utility/sound prediction), (ii) insufficient disclosure, and (iii) overbreadth.  Annis J concluded that all claims of the 191 Patent were invalid for inutility and insufficiency.

The parties agreed that the 191 Patent promised that the claimed compounds were useful in the treatment of Flaviviridae infections, including HCV infections, in humans and other hosts.  Annis J held that the 191 Patent did not promise any specific result or level of treatment, and therefore, Gilead must prove that Idenix did not demonstrate or soundly predict a scintilla of such utility.  It was common ground that Idenix had not demonstrated utility at the Canadian filing date.   Annis J held that the utility was also not soundly predicted, as the skilled person could not soundly predict any antiviral activity of the claimed compounds prior to synthesizing them. 

Annis J then held that the 191 Patent did not sufficiently disclose how to synthesize the claimed compounds and was therefore also invalid for insufficiency.

Finally, Annis J rejected Gilead’s novel overbreadth argument that Idenix had not made any claimed compound at the time the patent application was filed and published, and therefore, Idenix had not completed the act of invention, rendering any claims to unmade compounds overbroad.  Annis J expressed concern that accepting this argument would “[open] the floodgates somewhat to new challenges requiring a means to make the inventions for all unmade inventions relating in timing to disclosure, but affecting soundly predicted inventions.”

Gilead’s 657 Patent

Idenix counterclaimed to invalidate Gilead’s 657 Patent on the grounds of anticipation by Idenix’s (earlier) 191 Patent and under section 53 of the Patent Act for wilful misrepresentation by knowingly omitting a co-inventor.  Annis J dismissed Idenix’s counterclaim.

On anticipation, Annis J found that the 191 Patent disclosed the invention of the 657 Patent, but that this disclosure was not enabling as the 191 patent failed to disclose how to synthesize the compounds. 

Annis J also held that there was no wilful misrepresentation as the alleged co-inventor did not contribute to the invention, although he oversaw some testing.  He noted that the jurisprudence had suggested the omission of naming of a co-inventor would not be a “material” untrue allegation under section 53. 

Idenix has appealed to the Canadian Federal Court of Appeal.