Idenix Pharmaceuticals Inc., a maker of drugs for viral diseases, fell the most in seven months after losing a decision over whether it or Gilead Sciences Inc. was first to request a patent related to hepatitis C treatments.
Idenix fell 20 percent to $3.69 at 4 p.m. New York time, in the largest decrease since Aug. 16. The U.S. Patent and Trademark Office determined that Idenix’s application for compounds used to treat hepatitis C was filed later than Gilead’s, Idenix said in a statement on March 22.
The patent office’s ruling makes Foster City, California-based Gilead the “senior party” in the case and Idenix, based in Cambridge, Massachusetts, the “junior,” Idenix said. The agency will next determine which company was first to invent.
Idenix said it doesn’t believe the application at issue is relevant to any compounds under development. Idenix plans to begin the second of three phases of clinical trials on a hepatitis C therapies, IDX719, in the first half of this year.
Idenix fell 55 percent in the 12 months through March 22.