Teva Pharma. USA, Inc. v. Sandoz, Inc. (Fed. Cir. July 26, 2013)

The term “molecular weight” is indefinite because the claims do not indicate which average molecular weight measure is intended, and two different methods were relied on during prosecution to argue against/avoid rejection.)

Fall 2013

Robins Kaplan GENERICally Speaking: A Hatch-Waxman Litigation Bulletin

Case Name: Teva Pharma. USA, Inc. v. Sandoz, Inc., 723 F.3d 1363 (Fed. Cir. July 26, 2013) (Circuit Judges Rader, Moore, and Benson presiding; Opinion by Moore) (Appeal from S.D.N.Y., Jones, J.)

Drug Product and Patent(s)-in-Suit:Copaxone® (glatiramer acetate injection); U.S. Patent Nos. 5,800,808 (“the ’808 patent”), 5,981,589 (“the ’589 patent”), 6,048,898 (“the ’898 patent”), 6,054,430 (“the ’430 patent”), 6,342,476 (“the ’476 patent”), 6,362,161 (“the ’161 patent”), 6,620,847 (“the ’847 patent”), 6,939,539 (“the ’539 patent”), and 7,199,098 (“the ’098 patent”)

Nature of the Case and Issue(s) Presented: Teva, which markets Copaxone, sued Mylan and Sandoz for patent infringement. The patents-in-suit, which share a common specification, are listed in the Orange Book entry for Copaxone. They all include claims reciting a product called copolymer-1 and claims reciting methods of making copolymer-1. A sample of polymeric material like copolymer-1 typically consists of a mixture of individual polymer molecules that have varying molecular weights. There are different ways to describe the resulting distribution of molecular weight values. One approach uses statistical measures, including the peak average molecular weight (Mp), number average molecular weight (Mn), and weight average molecular weight (Mw). In a typical polymer sample, Mp, Mn, and Mw have different values. A second approach to describe the resulting distribution of molecular weight values is to describe how many molecules in a polymer sample have molecular weights that fall within an arbitrarily set range. The claims of the patents-in-suit use both approaches.

In its claim construction order, the district court did not distinguish in detail between the different contexts in which the term “molecular weight” was used. The district court rejected defendants’ argument that the term “molecular weight” was indefinite because it could refer to Mp, Mn, Mw, or yet another average molecular weight measure. It construed “molecular weight” as Mp and held that the claims are not indefinite. After a bench trial, the district court held that the asserted claims are not invalid for obviousness or lack of enablement, and that the Mylan and Sandoz accused products infringe all of the asserted claims. The Federal Circuit reversed the district court’s holding that some of the asserted claims were not indefinite, and affirmed the district court’s remaining holdings.

Why Defendants Prevailed: The Federal Circuit found that the term “molecular weight” is indefinite because the claims do not indicate which average molecular weight measure is intended.Teva’s attempt to resolve this ambiguity hinges on the prosecution history. But two statements it made to the USPTO directly contradict each other and render the ambiguity insoluble.

During prosecution of the ’539 patent, the USPTO Examiner rejected the pending claims as indefinite, stating that “the term ‘average molecular weight’…is indefinite since its method of measurement is not specified, i.e. [Mn], [Mw]…etc.” In response, Teva stated that a person or ordinary skill in the art would understand that ‘average molecular weight’ refers to Mp. The claims were allowed. During the prosecution of the ’847 patent, the USPTO Examiner made an analogous rejection over the same claim term, stating that “the term ‘average’ molecular weight…is meaningless as a limitation without specifying its basis, e.g., [Mw], [Mn], etc.” Teva overcame this rejection by responding that a person or ordinary skill in the art “could understand that kilodalton units implies a weight average molecular weight,” i.e., Mw. The Federal Circuit found that the “only basis upon which the Examiner could have agreed that the ’539 patent claims were not indefinite was that ‘molecular weight’ means Mp. In contrast, the only basis for the Examiner’s withdrawal of the indefiniteness rejection of the ’847 patent claims was that the same term means Mw. Teva’s two definitions cannot be reconciled.”

In support of its argument that the claims were not indefinite, Teva’s expert, Dr. Grant, testified that a skilled artisan would know that based on the curve depicted in Figure 1 and the accompanying legend, the claim terms “molecular weight” and “average molecular weight” denote Mp. Dr. Grant also testified that Example 1’s discussion of gel infiltration, which refers to the SEC method for measuring molecular weight, tells a skilled artisan that “molecular weight” refers to Mp. But Dr. Grant also opined that the SEC method “does not exclusively provide Mp—both Mn and Mw can also be obtained from the data generated by the SEC method after some calculations.”

With regard to enablement, the Federal Circuit perceived “no clear error in the fact findings on which the district court based its enablement conclusion.” Dr. Grant testified at length that it would have been routine for a skilled artisan to measure the molecular weight of copolymer-1. He explained that, “by calibrating the SEC column mentioned in the specification using methods that were well known at the time of filing, a skilled artisan could confirm the synthesis of copolymer-1 within the claimed molecular weight range.” Because defendants’ expert “failed to address the extensive literature that existed [at the time of filing] regarding SEC, self-standards, and universal calibration”—a finding made by the district court—the Federal Circuit agreed with Teva that the district court did not err in concluding that utilizing the calibration methods discussed by Dr. Grant would not require undue experimentation.

As to obviousness, the district court held that the asserted claims would not have been obvious in view of copolymer-1 compounds disclosed in the Teitelbaum prior art reference. The district court also determined that various secondary considerations supported the conclusion of non-obviousness. The Federal Circuit saw “no error in the district court’s obviousness analysis.” The Federal Circuit affirmed (i) that the prior art expressed a preference for higher molecular weight copolymer-1, and therefore taught away from the claimed invention, and (ii) fact findings relevant to secondary considerations, including the district court’s finding that “Copaxone® is coextensive with the asserted claims,” triggering a presumption of a nexus between the drug’s commercial success and the claimed invention.

Finally, the Federal Circuit affirmed that the asserted claims are infringed, literally and under the doctrine of equivalents.

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