Case:Novopharm Limited v. Eli Lilly and Company

Drug:atomoxetine (STRATTERA®)

Nature of Case:Impeachment Action - s. 60(1) of the Patent Act

Successful Party:Novopharm Limited

Date of Decision:September 14, 2010  


On September 14, 2010, the Federal Court allowed an impeachment action by Novopharm Limited ("Novopharm") and declared that Canadian Patent No. 2,209,735 (the "'735 Patent"), owned by Eli Lilly and Company ("Lilly"), is invalid and void for lack of utility. Barnes J. rejected Novopharm's arguments of obviousness and anticipation.

The '735 Patent claims the use of atomoxetine for treating attention deficit hyperactivity disorder ("ADHD") in adults, adolescents and children. The claimed utility was based on a 7 week, double-blind, placebo-controlled, cross-over trial to investigate atomoxetine's use as an ADHD treatment (the "MGH Study"). Lilly had previously investigated atomoxetine as a possible treatment for depression, however clinical trials failed to establish atomoxetine's efficacy for this use.


Justice Barnes found that the promise of the '735 Patent was the use of atomoxetine to "effectively treat humans with ADHD." As ADHD is a chronic disorder requiring sustained treatment, Barnes J. held that the '735 Patent implicitly promises "that atomoxetine will work in the longer term". Consequently, Barnes J. held that the utility requirement would be met if there was sufficient evidence that, at the Canadian filing date, atomoxetine was "clinically useful" in treating some patients with ADHD in the longer term, or alternatively, that such efficacy could be soundly predicted.

Justice Barnes agreed with Novopharm's experts that the MGH Study had several inherent limitations. In particular, Barnes J. accepted speculation that "one of the inherent limitations with the cross-over design of this study, particularly with such a small patient sample, is the risk that some of the patients may have been able to effectively break the blind by experiencing the side-effects of atomoxetine." Further, Barnes J. noted that "if even a small number of patients in a group of this size are able to identify when they are receiving the active compound as compared to placebo, the results obtained are easily compromised." The Court did not accept Lilly's reliance on the p-value of the clinical trials as a measure of statistical significance in view of the small patient sample. Thus, the Court held that due to the limitations of the MGH Study, its results did not demonstrate the clinical utility of atomoxetine to treat ADHD. "This was a clinical trial that was too small in size and too short in duration to provide anything more than interesting but inconclusive data." The Court also rejected Lilly's alternative position that the utility of the '735 Patent was soundly predicted, as there was no reference to the MGH Study in the patent itself.


Barnes J. focused on the obvious-to-try test and noted that "what may be obvious to examine may not be obviously useful if more than simple verification is required in proof." Justice Barnes held that the idea of trying atomoxetine to treat ADHD would have been obvious to any person skilled in the art who was thinking about the problem. However, Barnes J. did not accept Novopharm's assertion that "because the commonly used ADHD drugs were 'known or suspected to demonstrate noradrenergic activity', atomoxetine, as a selective NRI, would also be expected with a high degree of confidence to work." Rather, Barnes J. held that "the complexity of the neuropathological systems involved and the lack of knowledge in 1995 about why the successful ADHD drugs worked did not permit anyone to confidently predict whether any new compound could be expected to work." As a result, Barnes J. held that "Novopharm failed to establish that the inventive promise of the '735 Patent would have been obvious to a person skilled in the art as of its date of publication [sic]."


Novopharm alleged that the '735 Patent was anticipated by prior patents relating to atomoxetine. The Court rejected these arguments as none of the prior patents disclosed the inventive promise of the '735 Patent, namely the use of atomoxetine to treat ADHD.

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Novopharm Limited v. Eli Lilly and Company, 2010 FC 915