On Friday, July 29, 2011, the Federal Circuit issued a decision reversing the District of New Jersey's ruling that patent claims covering the use of tomoxetine (marketed as Strattera®) to treat attention deficit/hyperactivity disorder (''ADHD'') are invalid for lack of ''enablement/utility.'' Eli Lilly & Co. v. Actavis Elizabeth LLC, No. 2010-1500 (Fed. Cir. July 29, 2010). Read the decision here. Although nonprecedential, the opinion is important in that it indicates that at least certain members of the court recognize that the recent enablement/utility decisions in Rasmusson v. SmithKline Beecham Corp., 413 F.3d 1318 (Fed. Cir. 2005), and Janssen Pharmaceutica N.V. v. Teva Pharmaceuticals USA, Inc., 583 F.3d 1317 (Fed. Cir. 2009), are limited to their facts, and do not establish any general rule requiring experimental data to support the utility of method-of-use claims.
The '590 patent-in-suit covers a method of treating ADHD by administering ''an effective amount of tomoxetine.'' At the time the '590 patent application was filed, tomoxetine was a known compound that had been proven safe, but not medically effective, in clinical trials aimed at treating depression and urinary incontinence. Slip Op. at 5. The '590 application disclosed the use of tomoxetine to treat ADHD, but did not include any data in support of this claim given the then-absence of any animal model for experimental evaluation of potential ADHD treatments and the inability to test for any effect on ADHD in humans without FDA authorization. Id. at 5, 12. Human test data demonstrating the effectiveness of tomoxetine in treating ADHD was obtained, however, during the prosecution of '590 application. Id. at 6.
In its earlier Rasmusson decision, the Federal Circuit explained that ''the how to use prong of section 112 [concerning enablement] incorporates as a matter of law the requirement of 35 U.S.C. § 101 that the specification disclose as a matter of fact a practical utility for the invention.'' 413 F.3d at 1323 (quoting In re Cortright, 165 F.3d 1353, 1356 (Fed. Cir. 1999)). Relying on Rasmusson and the above-mentioned Janssen decision, the district court ''held that utility was not established because experimental data showing the results of treatment of ADHD were not included in the specification.'' Slip Op. at 11, 16.
In reversing the district court, the Federal Circuit explained that such data is not required because an assertion of utility in the specification '''must be taken as sufficient to satisfy the utility requirement . . . unless there is reason for one skilled in the art to question the objective truth of the statement of utility or its scope.''' Id. at 15 (citation omitted). The court distinguished Rasmusson as applying only to patent interferences ''where evidence of actual reduction to practice was required to establish a priority date earlier than that of an adverse claimant.'' Id. at 16. The court further explained that, where ''priority is not at issue, generally the applicant may provide data obtained either before or after the patent application was filed'' to establish utility. Id.
The Federal Circuit also distinguished Janssen as applying where a specification sets forth only a '''mere research proposal,''' and there is no '''reasonable correlation between a compound's activity and its asserted therapeutic use.''' Id. at 17. Contrasting this situation with that of '590 patent, the court noted that: (1) other compounds in tomoxetine's class of drugs were known to treat ADHD; (2) tomoxetine's ''safety for antidepressant activity had been established''; (3) ''the specification contained a full description of the utility''; (4) ''experimental verification had been obtained before the patent was granted''; and (5) ''the examiner had not requested additional information.'' Id. at 17.
The court's decision is also important in that it makes clear that reliance upon the knowledge of one of ordinary skill in the art to establish utility does not necessarily result in a finding of obviousness. In affirming the district court on this issue, the Federal Circuit determined that ''there was no evidence that use of tomoxetine had been identified as a possible solution to the problems of treating ADHD, nor that the exercise of common sense would have led a person of ordinary skill to test tomoxetine for treatment of ADHD.'' Id. at 8.1 Thus, the state of the art supported the credibility of the disclosed utility, but at the same time did not render that utility obvious.
Considering the significance of method-of-use claims to the pharmaceutical industry, it will be interesting to watch whether the Federal Circuit continues to implement this interpretation of Rasmusson and Janssen when addressing enablement/utility challenges.
1The Federal Circuit also affirmed the district court on the issues of ''enablement/scope'' and inducement of infringement, and reversed on contributory infringement. With respect to induced infringement, the court held that substantial off-label uses do not preclude such infringement where the proposed generic product ''is labeled solely for the patented use.'' Id. at 19. The Federal Circuit similarly ruled that off-label uses do not avoid contributory infringement where the product ''is authorized to be sold solely for the infringing use.'' Id. at 20.