Motivation to Combine References Pivotal in Vacatur of Preliminary Injunction Against Teva
In a patent attack under §103 based on a combination of references, the Federal Circuit disagreed that Teva failed to raise a “substantial question of validity,” required to defeat a likelihood of success showing in support of an injunction. Claims of issued, prior art patents are presumed to comply with §112, and a prior art claim reciting several group members is – absent a statement to the contrary -- a representation that the members can be used interchangeably without undue experimentation. Here, the interchangeability of prior art claimed group members was sufficient to support a motivation to combine under §103.
In Abbott Labs. v. Andrx Pharms., Inc. & Teva, No 05-1433 (Fed. Cir. June 22, 2006), the Federal Circuit vacated the grant of a preliminary injunction to Abbott, based on the Court’s conclusion that a substantial question of validity precluded a finding that Abbott was likely to succeed on the merits.
Abbott’s ‘718 patent claimed an extended release formulation of erythromycin derivatives (here, clarithromycin) combined with a polymer. The CIP ‘616 patent claims a method of reducing adverse gastrointestinal side effects of erythromycin-derived drug formulations by using extended release formulations. Abbott sued Teva for infringement of its ‘718 and ‘616 patents, and moved for a preliminary injunction after FDA approved Teva’s ANDA for generic clarithromycin products. The district court granted the injunction based on Teva’s failure to prove that claims 2, 4, and 6 of the ’718 patent were invalid for obviousness. In so ruling, the district court concluded that Teva had not rebutted Abbott’s showing of irreparable harm, alleged to be “irreversible market share losses.”
On appeal, the Federal Circuit construed claims 2 and 4 of the ‘616 patent as requiring an erythromycin derivative, a polymer, and specific pharmacokinetic parameters that the composition must meet. Teva argued that Abbott’s own ‘190 patent disclosed compositions of clarithromycin in an alginate matrix administered once a day (to increase the bioavailability of the active ingredient so as to be equivalent to the immediate release, twice a-day compositions). When combined with Pfizer’s ‘422 publication disclosing controlled-release formulations of azithromycin with HPMC, Teva urged the Abbott claims were invalid under §103.
Rejecting Abbott’s claim that azithromycin and clarithromycin were so different that there was no motivation for a person of skill in the art to interchange the HPMC polymer of the ’422 publication with the alginate matrix of the’190 patent, the Federal Circuit relied on a dependent claim in the ‘190 patent having a Markush group that included both compounds:
The ’190 patent itself demonstrates that Abbott has represented to the PTO and the public in general that a person of ordinary skill in the art can expect to successfully substitute azithromycin into a clarithromycin controlled release composition without undue experimentation.
In considering irreparable harm, the Federal Circuit concluded that neither party was favored in the analysis since Abbott had shown neither likelihood of success on the merits nor the inability to be compensated by money damages, and Teva had not shown that monetary damages would be sufficient compensation.
Dissenting, Judge Newman criticized the panel majority’s "substantial question" of invalidity standard for Teva as failing to incorporate the presumption of validity and the burdens of proving invalidity that would inhere at a trial on the merits. She also charged the panel majority with employing impermissible hindsight in combining portions of the ‘190 and ‘422 references by ignoring the uncontradicted statement of Abbott that “what works for a product in an alginate matrix is not predictably applicable to other products.”