In a Sign o’ the Times, Sanofi-Aventis and Bristol-Myers Squibb have reached a settlement agreement with Apotex in the patent infringement lawsuit pending between the parties in the US District Court. The suit relates to the validity of a composition of matter patent for clopidogrel bisulfate, the active ingredient in Plavix.

Plavix is one of the three top-selling drugs in the world with sales of $5.4 billion. In Sanofi’s suit against Apotex and Dr. Reddy in the U.S. Apotex and Dr. Reddy argued that the patent for the active ingredient, which expires in 2011, is not sufficiently different from another Sanofi patent that expired two years ago.

The first patent covering Sanofi’s oral antiplatelet chiral drug clopidogrel bisulfate (US 4,529,596), was filed in 1983 and expired in July 2003, and claims both enantiomers and their mixture, whereas a later patent (US 4,847,265), due to expire in 2011, claims only the (+)-enantiomer.

The earlier patent claimed, but did not describe, the (+)- and (–)-enantiomers, although it states that “the invention relates both to each enantiomer and their mixture.” In the description of the activities of each enantiomer in the ‘265 patent, data show that the (+)-enantiomer is pharmacologically superior in activity and less toxic than both the (–)-form and the racemate.

Under the terms of the proposed settlement, Sanofi-Aventis will grant Apotex a royalty-bearing license under the ‘265 patent to manufacture and sell its FDA-approved clopidogrel bisulfate product in the United States, and Apotex would agree not to sell another clopidogrel product in the United States until the effective date of the license.

Keep in mind that the proposed settlement is subject to certain conditions, including antitrust review and clearance by the Federal Trade Commission and state attorneys general. There is a risk that antitrust clearance won’t be obtained. Sanofi and Bristol-Myers have approached Dr. Reddy’s to discuss a possible settlement of this matter, too.

The growing ability of patent holders to settle disputes could be a sign that things are moving more in favor of branded drug firms on patents after years of aggressive attack from generic firms. This follows the victories last year by Pfizer with its patent on Lipitor and Eli Lilly with its patent on Zyprexa.

Comments are closed.