Merck Sues Barr Over Generic Drug

Merck & Co. sued Barr Laboratories Inc. in an effort to stop it from making a generic version of Merck’s top-selling osteoporosis drug, Fosamax.

Merck executives declined to comment on the patent-infringement suit that was filed in federal court in Delaware. Analysts expect sales of Fosamax, a drug that slows bone loss associated with menopause and aging, to top $1.5 billion this year.

Merck, which owns patents covering the processes for producing the drug, said Barr asked the Food and Drug Administration to let it develop drugs similar to Fosamax as part of its generic lineup. Merck’s patents don’t begin to expire until 2007.

Pomona, N.Y.-based Barr, which has a track record in challenging patent protections for popular drugs, countered that Merck’s patents covering the osteoporosis drug weren’t valid and should be challenged.

Shares of Whitehouse Station, N.J.-based Merck rose $2.40 to $67.70, and Barr shares rose $1.05 to $83.75, both on the NYSE.