Sofosbuvir - Australia

On Dec 07, 2017, Federal court of Australia upheld the invalidity decision of lower court in Sofosbuvir case and dismissed the appeal of Idenix.

The appellants (Idenix) are the registered owners of patent no. AU2003247084, titled “Modified 2' and 3'-nucleoside prodrugs for treating flaviviridae infections” (the Idenix patent). The Idenix patent relates to compounds for the treatment of flaviviridae infections, including the hepatitis C virus (HCV) infection. The respondents (Gilead) are the registered owners of patent no. AU2004253860 (the Clark patent). Gilead has sought to sell in Australia a pharmaceutical drug containing or comprising an effective amount of a compound called sofosbuvir to treat HCV. Gilead commenced proceedings in this Court against Idenix seeking a declaration that claims 7 to 41 (inclusive) of the Idenix patent were invalid. It contended that the Idenix patent was invalid on the grounds that the patent did not disclose a manner of manufacture, lacked novelty, lacked fair basis, lacked utility, and lacked sufficiency. In turn, Idenix brought a cross-claim alleging that Gilead threatened to infringe various claims of the Idenix patent through the supply of pharmaceutical compositions containing the compound sofosbuvir. Gilead conceded, subject to its invalidity assertions, that sofosbuvir infringed claims 7 and 8 as well as dependent claims 10 and 13 of the Idenix patent. The primary judge found the Idenix patent to be invalid on the grounds of insufficiency in respect of claims 7 to 41 (Gilead Sciences Pty Ltd v Idenix Pharmaceuticals LLC (2016) 117 IPR 252; [2016] FCA 169).

Idenix then appealed the primary judge’s decision on the basis that her Honour erred in her conclusions as to insufficiency, certain aspects of fair basis and inutility. Further and consequentially, Idenix contended that the primary judge erred in dismissing its cross-claim given that her Honour premised that dismissal on relevant claims of the Idenix patent being invalid. Gilead has filed a notice of contention in which it challenges the primary judge’s conclusions that the Idenix patent was not invalid on the grounds of lack of novelty and other aspects of lack of fair basis.

With respect to lack of sufficiency, Gilead contended that the Idenix patent did not identify which of the compounds within claim 7 were effective for the treatment of flaviviridae infections or HCV and did not describe how to identify such compounds. It was common ground that a compound that is within claim 7 is the 2'-methyl-“up”-2'-fluoro-“down” nucleoside. The principal issue on this aspect was whether at the priority date a person skilled in the art who was armed with the Idenix patent and relying only upon common general knowledge could have synthesised a compound of claim 7 without new invention or addition or a prolonged study of matters presenting initial difficulty. Federal Court found no error in primary judge’s analysis and held that there was clear and compelling evidence before the primary judge justifying her finding that the requirement was not met. Indeed, part of the evidence before her Honour was material demonstrating that Idenix was unable to obtain a claim 7 compound despite having a team of skilled scientists and external expert consultants engaged in a prolonged attempt to do so for a period of nearly three years.

Thus court finally dismissed Idenix’s appeal and also Gilead’s other grounds of contention.