Alcon Research Ltd. v. Barr Labs. Inc.

January 03, 2012

GENERICally Speaking: A Hatch Waxman Litigation Bulletin

Case Name: Alcon Research Ltd. v. Barr Labs. Inc., Civ. No. 09-CV-0318-LDD, 2011 U.S. Dist. LEXIS 143007 (D. Del. Dec. 13, 2011) (Davis, J.)

Drug Product and Patent(s)-in-Suit: Travatan® and Travatan Z® (travoprost); U.S. Pat. Nos. 5,631,287; 6,011,062; 6,503,497; and 6,849,253

Nature of the Case and Issue(s) Presented: Whether the asserted claims of the ‘287 and ‘062 patents were valid and infringed by the defendants' generic formulation.  Alcon Research Ltd. (Alcon) initially asserted the ‘497 and ‘253 patents in addition to the ‘287 and ‘062 patents.  After the first day of trial, co-defendant Par Pharmaceutical, Inc. (Par) settled with Alcon.  At that point, Barr Labs. Inc. (Barr) stipulated that its generic formulation infringed the asserted claims of the ‘497 and ‘253 patents, and that those patents were valid (according to the FDA Orange Book, the ‘497 and ‘253 patents expire on May 6, 2012).  Trial then proceeded to determine whether the asserted claims of the ‘287 and ‘062 patents were valid and infringed by Barr's generic product.

Why Barr Prevailed:  (Insufficient evidence of infringement; lack of enablement; failure to meet written description).  The Court carried out a multi-part analysis of the asserted claims of the ‘287 and ‘062 Patents, including infringement, enablement/written description, indefiniteness, anticipation and obviousness.  The court first analyzed whether Barr's generic solution contained a sufficient quantity of polyethoxylated castor oil ("PECO") to constitute a "chemically stabilizing amount."  The Court immediately faulted Alcon for not carrying out a test to determine whether the PECO concentration in the proposed Barr generic solution did in fact chemically stabilize the active ingredient.  Instead, Alcon relied exclusively on the testimony of its expert witness and one of the inventors of the patents-in-suit.  The expert relied on an internal Alcon study involving a comparison of the chemical stability of two travoprost-containing solutions over an eight week period of time (but not the exact generic formulation proposed).  One solution was composed of travoprost by itself and the other included a specific concentration of a type of PECO in addition to travoprost.  The Court found that the study failed to establish that the solution containing PECO exhibited a marked increase in chemical stability over the solution that did not contain PECO.  Further, the study did not definitively establish that the minimal amount of degradation observed was due solely to chemical degradation, as opposed to physical degradation or experimental error.  The Court next considered the testimony of the inventor of the ‘287 and ‘062 patents, but did not find it persuasive; Alcon never designated the inventor as an expert and the inventor provided contradictory and confusing testimony.  Additionally, Alcon's own internal documents showed  that Alcon believed the addition of PECO to aqueous solutions resulted in increased physical, rather than chemical, stabilization of active ingredients.  The Court concluded that Alcon had failed to prove by a preponderance of evidence that Barr manufactured its generic solution by "adding a chemically stabilizing amount of polyethoxylated castor oil" to "enhance the chemical stability of the solution" and therefore did not infringe the asserted claims of the ‘287 and ‘062 patents.

The Court next addressed the issue of whether the asserted patents met the enablement requirement.  It found that the asserted claims were extremely broad, the technology of stabilizing prostaglandins was extremely unpredictable, and that the disclosures in the asserted patents provided minimal guidance to a person skilled in the art on how to practice the full scope of the claimed invention.  The Court applied each of the eight Wand factors and found that Barr had proved by clear and convincing evidence that the asserted patents were invalid for lack of enablement.  The Court found that the asserted claims of the ‘287 and ‘062 Patents also failed to meet the written description requirement under a similar analysis as the one it undertook with respect to enablement.

Thereafter, the Court considered whether the terms "therapeutically effective amount" and "enhancing the chemical stability" rendered the asserted claims indefinite.  The Court held that a person skilled in the art could understand sufficiently those terms, and therefore those terms did not render the ‘287 and ‘062 patents indefinite.

Barr introduced a single patent it considered to be prior art in an attempt to prove anticipation under 35 U.S.C. § 102.  The Court determined that the proffered ‘273 patent was not prior art because the inventors of the ‘287 and ‘062 patents conceived and reduced to practice enough of the claimed invention before the December 15, 1993 filing date of the referenced ‘273 patent.

Last, the Court reviewed six prior art references that Barr asserted for support of its obviousness defense.  Although each reference contained certain elements claimed in the ‘287 and ‘062 patents, the Court found that Barr's expert failed to adhere to the "expansive and flexible approach" the Supreme Court established in KSR.  Instead, the expert had impermissibly used hindsight to combine the six references.  The Court held that a person having ordinary skill in the art at the time of invention would not have had reason or motivation to combine the references, absent the use of impermissible hindsight.     

Though Barr prevailed on its attacks against the ‘287 and ‘062 patents, the court concluded that FDA approval of Barr's generic formulation could not occur earlier than the date of expiration of the last to expire of the ‘497 and ‘253 Patents (i.e., May 6, 2012).

Oren D. Langer


Managing Partner, New York Office
Member of Executive Board

Ryan M. Schultz


Pronouns: he/him

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