Chiron Halts Work on Arthritis Medicine

Chiron Corp., one of the world’s biggest biotechnology companies, said it has stopped developing an experimental arthritis medicine after two studies failed to show benefits from the treatment. Shares of Chiron, which is part-owned by Switzerland’s Novartis, fell $7.23, or 14.6%, to $42.44 in Nasdaq trading. A trial in patients who had arthroscopic knee surgery found no significant difference between the effects of the medicine, rhIGF-I, and a placebo, Chiron said. Another study of patients having knee replacement surgery failed to find a “compelling” benefit, the company said. The tests were part of the second of three phases of research generally required to win regulatory approval of a new medicine. The results are a setback to Emeryville, Calif.-based Chiron’s efforts to enter a multibillion-dollar market for treatments for osteoarthritis. The insulin-like growth factor rhIGF-I is a compound designed to stimulate the growth of cartilage and inhibit its loss. The drug showed good results in animal studies and was among products targeted for speedy development two years ago.