Allergan, Inc. v. Sandoz Inc.

An ANDA product having a pH range of 6.8-7.2 infringes, literally and under the doctrine of equivalents (amendments related only tangentially to pH), a claim term related to pH of “about 7.3;” and given the unpredictability of ophthalmic formulation, among other things, the patents in suit are not invalid.

Spring 2014

Robins Kaplan GENERICally Speaking: A Hatch-Waxman Litigation Bulletin

Case Name: Allergan, Inc. v. Sandoz Inc., Case No. 11-cv-441, Dkt. No. 136 (E.D. Tex. Jan. 13, 2014) (Schneider, J.)

Drug Product and Patent(s)-in-Suit:  Lumigan® (bimatoprost); U.S. Patents Nos. 7,851,504 (“the ’504 patent”), 8,278,353 (“the ’353 patent”), 8,299,118 (“the ’118 patent”), 8,309,605 (“the ’605 patent”), and 8,339,479 (“the ’479 patent”)

Nature of the Case and Issue(s) Presented:  Allergan asserted patent infringement claims against various defendants for attempting to make and market generic versions of Lumigan. Some defendants argued that their ANDA products would not infringe the patents in suit because those defendants stated in their ANDA that the product’s pH range during its shelf life is 6.8–7.2. The asserted claims of the ’502, ’497, and ’605 patents all require a pH of “about 7.3.”

Defendants also argued that the asserted claims were invalid as obvious in view of the prior art. Allergan, on the other hand, asserted that the prior art taught away from the claimed invention of using 0.01% bimatoprost with 200 ppm benzalkonium chloride. Finally, Allergan argued that that it was entitled to a permanent injunction because it would suffer irreparable harm if defendants were allowed to enter the market with their proposed ANDA products.

The court reached the following conclusions: (i) defendants’ proposed generic drug products infringed Allergan’s patents; (ii) Allergan’s patents are not invalid and are enforceable; and (iii) Allergan was entitled to a permanent injunction preventing defendants from introducing generic versions of Lumigan until the expiration of Allergan’s patents.

Why Allergan Prevailed: The asserted claims were not invalid, because the prior art did not teach the claimed invention. Ophthalmic formulation is a very unpredictable art. The referenced prior art did not suggest that there was a finite number of predictable solutions. Indeed, some of the asserted prior art taught away from the claimed invention. The court found considerable differences between the prior art and the claimed invention. The court further rejected defendants’ argument that it would have been obvious to one of skill to try the claimed invention because of the numerous possibilities available, skepticism in the prior art, and the unpredictability in the art.

Next, the court found that the defendants’ proposed ANDA products infringed the patents in suit. As for some of defendants’ arguments concerning the pH limitation, the court found that pH levels around 7.0 were infringing both literally and under the doctrine of equivalents. The court rejected defendants’ argument that prosecution history estoppel applied because the amendments made during prosecution only tangentially related to the pH limitation.

Finally, the court granted a permanent injunction in favor of Allergan because the irreparable harm to Allergan outweighed the competition in the market that will result should the proposed ANDA products enter the market. The court also reasoned that patent protection was a greater public interest than entry of generics into the market place.

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