Hoechst Marion Roussel won a patent rights case against Baker Norton Pharmaceuticals for its terfenadine drug, Seldane, in 1996. Baker Norton Pharmaceuticals is a subsidiary of IVAX Corporation, which produced terfenadine drug. Its generic version was said to infringing the patent rights of Hoechst Marion Roussel on terfenadine.

Seldane was an oral antihistamine medicine. It contained Terfenadine as main active ingredient. It was a very popular drug and was introduced in the market in 1985. It was used for treatment of allergic symptoms. It was manufactured by Hoechst Marion Roussel. The pharmaceutical company is now known as Aventis. It was recalled by FDA in 1997 after it was linked to serious cardiac arrhythmia. Seldane (terfenadine) was one of Hoechst Marion Roussel’s top-selling products.

Baker Norton Pharmaceuticals, a subsidiary of IVAX notified the company that it had submitted a new drug application to FDA for marketing of generic terfenadine drug in 1994. Hoechst Marion Roussel filed the lawsuit against Baer Norton Pharmaceuticals, a subsidiary of IVAX. It filed the lawsuit according to the provisions of the 1984 Waxman Hatch Act. This act asks a patent holder to file suit after it receives notice of a proposed generic new product. 1984 Waxman Hatch Act, also provided that FDA cannot approve the generic drug for 30 months from the filing of this lawsuit, if the result has not come and the case is pending in the federal court.

The lawsuit stated that if IVAX would commercially manufacture, use and sale terfenadine, it would be an infringement of the claims of the 129 patents. It would be causing harm to Hoechst Marion Roussel by affecting its sales proceeds. The lawsuit was filed to protect the company’s patent rights covering terfenadine, the main active ingredient of its antihistamine drug Seldane, which was used for treatment of allergies.

The federal magistrate Ted E. Bandstra at united States District Court for the Southern District of Florida, Miami, came to a conclusion that generic version of Seldane would infringe the patent rights of Hoechst Marion Roussel on its antihistamine drug Seldane.

He recommended a partial summary judgment in favor of Hoechst Marion Roussel. It was then moved forward to judge Frederico A. Moreno of the United States District Court for the Southern District of Florida for approval.

Hoechst Marion Roussel got upper hand against its rival Baker Norton Pharmaceuticals, Inc., a subsidiary of IVAX Corporation after this favorable decision came. US District Court for the Southern District of Florida deemed that the generic version of the drug by IVAX was infringing Hoechst Marion Roussel’s patent right and thus it could not get its marketing approval in U.S. until 1999, when its patent expired. Meanwhile IVAX won a tentative approval for its generic terfenadine in February 1996.

Later Seldane was recalled by FDA. In 1997 FDA announced withdrawal of Seldane from the U.S. market. It was a result of many new evidences surfacing which linked use of Seldane and other terfenadine drugs with severe side effects such as cardiac arrhythmia. FDA asked Hoechst Marion Roussel, now known as Aventis pharmaceuticals, manufacturer of Seldane and other terfenadine containing drugs such as Seldane-D, to voluntarily withdraw these drugs from the market. Hoechst Marion Roussel and Baker Norton Pharmaceuticals, the manufacturer of the Seldane decided to voluntarily stop the distribution and marketing of all terfenadine drugs including Seldane from U.S. market after FDA’s decision of recall.