Two recent patent decisions in the United States and Canada highlight the differences in the application of utility and disclosure even though the relevant statutory sections are the same. The patents at issue claim the use of atomoxetine hydrochloride for use in the treatment of ADHD. The U.S. patent was found to be valid even though the results of a clinical trial were received after the U.S. application was filed. The positive results were received before the Canadian patent application was filed, yet the Canadian patent was invalidated on a utility attack.

ADHD is a chronic and inheritable neurobiological disorder characterized by an inappropriate level of inattention, hyperactivity and impulsiveness. The disorder impacts 3 to 5 per cent of school-age children, most of whom carry symptoms into adulthood. It can result in the significant impairment of school, family, and social relationships. There is no cure for ADHD, but symptoms may be ameliorated by medication. Stimulants are controlled substances and are not effective for all patients. Tricyclic antidepressants (TCAs) were also used but concerns were raised when desipramine was implicated in the sudden death of some children.

Eli Lilly's Strattera atomoxetine hydrochloride was the first non-stimulant ADHD drug approved by the FDA and Health Canada. Atomoxetine was synthesized around 1980 and tested extensively in the treatment of depression. The results of the clinical trials lead to the abandonment of atomoxetine for use in depression but did show that atomoxetine was well-tolerated by patients.

Lilly scientists conceived that atomoxetine may be effective in the treatment of ADHD and so they approached leading ADHD researchers at the Massachusetts General Hospital (MGH), the teaching hospital associated with Harvard University, to conduct a clinical trial. Lilly funded an ADHD study, provided atomoxetine and placebo and allowed MGH access to Lilly's confidential FDA f lings for the purpose of running the study. The overall response rate for atomoxetine was clinically and statistically higher than placebo. The relative timing of the study is as follows: (1) FDA approval for the study; (2) U.S. patent application filed; (3) positive results received by Lilly and published at the world's largest meeting of ADHD practitioners; and (4) Canadian patent application filed.

The disclosure and claims of the U.S. and Canadian patents are virtually the same. The patents disclose that atomoxetine is effective in all forms of ADHD in children, adolescents and adults. The improved safety profile of atomoxetine is disclosed and recommended dosing is provided. In both jurisdictions, the central invalidity argument related to the fact that the results of the MGH study were not provided in the patent disclosures.

The U.S. Court of Appeals for the Federal Circuit (Eli Lilly and Co. v. Actavis Elizabeth LLC et al., Appeal No. 2010-1500 (Fed. Cir. July 29, 2011)) overturned the trial decision, which found the patent invalid for "lack of enablement/utility." The Court of Appeal reasoned the invention had utility and the specification met the objective disclosure test required by the statute. On the other hand, the Canadian Federal Court and Federal Court of Appeal held the patent invalid for want of disclosure of sound prediction (Novopharm v. Eli Lilly and Co., 2010 FC 915, 87 C.P.R. (4th) 301, upheld 2011 FCA 220, 94 C.P.R. (4th) 95). Under current Canadian law, a utility analysis is measured by reference to the "promise of a patent." The trial judge said that the patent implicitly promised long-term usefulness. Because long-term testing had not been done at the time of filing, the patent was based upon sound prediction, which requires enhanced disclosure of the factual basis and a sound line of reasoning for the prediction. As such, the results of the MGH study were required to be disclosed.

There is nothing in the Canadian Patent Act that requires this "enhanced disclosure" for inventions based upon sound prediction. If a patent discloses a new, non-obvious and useful invention and provides sufficient information to allow a person of skill to make and use an invention, there should be sufficient consideration for the grant of a patent. Increasing utility standards by reference to a promise of the patent discourages applicants from discussing the attributes of their inventions for fear of being held to a higher utility standard. It is hoped that future cases will clarify this law.

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