Merck & Co. said Tuesday the Food and Drug Administration on Tuesday said it will not approve an experimental sarcoma drug unless Merck conducts further testing.
Merck has asked the FDA to approve the drug, ridaforolimus, to help repress bone and tissue sarcoma in patients whose cancer is already in remission. The company said Tuesday that the FDA wants to see more human testing of the drug to further demonstrate its safety and effectiveness.
The Whitehouse Station, N.J., company said it "remains confident in the potential of ridaforolimus."
Merck had asked the FDA to approve ridaforolimus as a maintenance therapy. The FDA has only approved a few cancer drugs for maintenance use, and a panel recommended against approving ridaforolimus in March. Panel members said they wanted to see clearer evidence that the major side effects of the drug were worthwhile for patients. Those side effects included lung irritation, kidney failure and high blood pressure.
Merck acquired the rights to ridaforolimus from Ariad Pharmaceuticals Inc. of Cambridge, Mass., in 2010. Merck will pay Ariad $25 million if the drug is approved, and another $10 million if it is approved in Europe. Ariad will also get royalty payments on any sales. Merck is responsible for all development costs.
Ariad shares gained 3.7 percent to $16.20 on Tuesday while Merck shares rose 4 cents to $37.50. In aftermarket trading, Ariad shares lost 9 cents to $16.11 and Merck stock fell 12 cents to $37.38.