Allergan, Inc. v. Watson Laboratories, Inc.

Case Name: Allergan, Inc. v. Watson Laboratories, Inc., Civ. No. 09-511-GMS, 2012 U.S. Dist. LEXIS 47027 (D. Del. March 31, 2012) (Sleet, C.J.)

Drug Product and Patent(s)-in-Suit: Sanctura XR® (trospium chloride); U.S. Pat. Nos. 7,410,978 ("the '978 patent"), 7,759,359 ("the '359 patent"), 7,781,448 ("the '448 patent"), 7,781,449 ("the '449 patent"), and 7,763,635 ("the '635 patent").

Nature of the Case and Issue(s) Presented: The issue here concerns whether the asserted claims of the '978, '359, '448, '449, and '635 patents, which cover methods of treatment and dosages related to plaintiffs' branded Sanctura XR drug product are valid and infringed by the defendants' proposed generic products.  On June 1, 2009, Watson sent plaintiffs a Paragraph IV notice indicating that it had submitted an ANDA seeking to manufacture a generic trospium chloride preparation before the expiration of the '978 patent.  Watson later amended its ANDA and sent additional Paragraph IV notices regarding the '359, '448, '449, and '635 patents.  Plaintiffs sued Watson alleging infringement of those patents.  Sandoz followed a similar path, sending the plaintiffs a Paragraph IV notice on November 4, 2009 in relation to the '978 patent.  Sandoz later amended its ANDA to encompass the '359, '448, and '449 patents and sent additional Paragraph IV notices to the plaintiffs to that effect.  Plaintiffs sued Sandoz for infringement of those patents.  Last, Paddock sent a Paragraph IV notice to the plaintiffs on April 26, 2010 regarding the '978 patent, and later sent additional Paragraph IV notices to plaintiffs regarding the '359, '635, '448, and '449 patents.  Plaintiffs filed suit against Paddock alleging infringement of its patents.  In October 2010 the three cases were consolidated and the United States District Court for the District of Delaware held a seven-day bench trial that began on May 2, 2010.  The parties then filed their proposed findings of fact and conclusions of law.           

Why Watson, Sandoz and Paddock Prevailed:  At the time this case went to trial, plaintiffs asserted an identical set of claims from the '978, '448, '449, and '359 patents against each of the defendants.  Defendants counterclaimed that the asserted claims were anticipated and obvious. Defendants further alleged that the '978 and '449 patents were indefinite.

The Court first addressed obviousness by noting at the outset that the asserted claims did not cover a new drug, a new method of treatment, nor a novel way of formulating trospium.  Instead, the asserted claims were "directed to pharmaceutical compositions that allow for once daily dosage forms of trospium."  Plaintiffs' nonobviousness argument was based on the concept that a number of attributes would have made trospium a challenging molecule to use in a once-a-day formulation.  Specifically, the plaintiffs identified the following alleged formulation bundles: (i) permanent positive charge; (ii) negligible colonic absorption; (iii) paracellular absorption; (iv) wide range of variable half-life values; and (v) binding to mucus and feces.  But the prior art the defendants relied on disclosed multiparticulate formulations using extended, delayed and immediate release pellets; multiparticulate formulations designed to target the lower GI tract; properties of trospium that made it a good candidate for once-a-day formulation, such as its relatively long half-life; and the market drive to formulate once-daily formulations.  In fact, a number of prior art references specifically suggested that trospium could be used in a once-a-day formulation.  The Court further referenced a substantial number of prior art references that taught extended-release formulations, specifically targeted for release within the colon, and discussed prior art that disclosed trospium as a good candidate for a once-a-day formulation.  In view of this overwhelming prior art, the Court found all asserted claims obvious, and therefore invalid.  In doing so, the Court found that plaintiffs' secondary considerations of non-obviousness could not rebut its obviousness finding.  Moreover, the Court did not give much weight to plaintiffs' evidence that the defendants had copied their formulation, noting that in the context of Hatch-Waxman litigation, generics are required by law to make near identical versions of the patented drug.

With regard to anticipation, defendants cited a reference identified as the Fuhr/Schroder Poster, which described a study that measured trospium concentration in eight subjects after administration of an immediate-release formulation, an extended-release formulation, and a placebo.  The Court found that the reference did not anticipate the asserted claims because it did not disclose claim elements related to a formulation suitable for once-a-day trospium administration or a formulation designed for release in the lower GI tract.

The Court next rejected defendants' indefiniteness argument, finding that, based on expert testimony and the disclosure in the patent specifications, the terms "comparable to" and "minimizing the occurrence" were adequately supported and were not indefinite.