Astellas and Boehringer Ingelheim Defeat Ranbaxy in Flomax Case
Astellas Pharma et al. v. Ranbaxy et al., No. 05-2563 (D. N.J. 2007)
A federal district court last week upheld Astellas Pharma's patent on Flomax (tamsulosin HCl), preventing Ranbaxy from marketing a generic version of the drug until the patent expires in 2009. Flomax is a treatment for benign prostatic hypertrophy (BPH), with annual sales of approximately $600 million in the United States. Boehringer Ingelheim is Astellas Pharma's U.S. marketing partner.
Astellas and Boehringer filed the lawsuit in 2005 after Ranbaxy applied to the FDA to market generic Flomax and asserted that Astellas Pharma's U.S. Patent No. 4,703,063 is invalid. The '063 patent covers a class of chemical compounds that includes the active ingredient in Flomax, tamsulosin, as well as related pharmaceutical compositions.
Early in the litigation, Ranbaxy admitted that its generic Flomax infringes the '063 patent and dropped several defenses. Ranbaxy's only remaining defense to patent infringement was that the '063 patent is invalid due to obviousness-type double patenting. The doctrine of obviousness-type double patenting prohibits a party from obtaining an extension of its exclusive rights in a later patent that is not sufficiently distinct from a commonly owned earlier patent. Specifically, Ranbaxy claimed that the '063 patent is invalid because Astellas had previously obtained U.S. Patent No. 4,373,106, which covers processes for making the class of chemical compounds covered by the later '063 patent.
Judge Mary L. Cooper of the U.S. District Court for the District of New Jersey issued the opinion. Judge Cooper cited several precedents in support of the principle that later compound claims can be patentably distinct from earlier process claims. Furthermore, according to Judge Cooper, Ranbaxy did not "point to, and the Court could not find, one double-patenting case where a later product claim was anticipated by the earlier process claim for making that product." Ranbaxy's expert witness admitted "that the '106 patent only claims the processes for making the compounds and the '063 patent only claims the compounds themselves," leaving no factual disputes to decide. Accordingly, Judge Cooper granted summary judgment of patent validity to Astellas and Boehringer.
Ranbaxy has appealed the case to the Court of Appeals for the Federal Circuit.
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once process patent obtained for a compound, then the compound will never be claimed in another patent as it was disclosed earliar.
Posted by: mohammed yaseen | April 07, 2007 at 06:30 AM