Ribapharm Falls 19% on Schering Settlement

Shares of Ribapharm Inc., a maker of hepatitis C drug ribavirin, fell 19% after marketing partner Schering-Plough Corp. settled a patent lawsuit with a rival drug maker.

The shares fell $1.13 to $4.73 on the NYSE. They have fallen 53% in the last 12 months.

Schering-Plough said it would license patents it holds on ribavirin to Three Rivers Pharmaceuticals, which is waiting for U.S. regulatory approval to sell a version of the medicine.

Three Rivers, which agreed to pay undisclosed royalties to Schering-Plough, remains involved in a lawsuit with Ribapharm.

Shares of ICN Pharmaceuticals Inc., which owns about 80% of Ribapharm, fell 49 cents, or 5%, to $9.26, also on the NYSE.