Regeneron Pharmaceuticals Inc. revealed that the Food and Drug Administration has been closing down the development of an experimental pain-killer. The said pain-killer manufactured by Regeneron is said to be able a good treatment for death of bone tissue.

Last week, FDA admitted the halting of the pain drugs. In addition, the agency also confirmed that there was a case of what is known as avascular necrosis which involved a drug similar to Regeneron’s anti-nerve growth factor. Regeneron did not name the other product but has started developing treatment with Paris-based Sanofi-Aventis SA.

Another group that halted the said studies was the New York-based Pfizer, Inc. Pfizer is the world’s largest drug maker and halted the studies done to its nerve-growth inhibitor tanezumab. This was done because of the request of the U.S, regulators in June and July.

On the other hand, Regeneron said that its own painkiller was shown to be effective in patients with knee osteoarthritis. In a statement by the Regeneron today, the company said that the FDA believes that its case is actually showing an evidence suggesting bone problems with the entire types of anti-nerve growth drugs. In addition, Regeneron said that there are also no current and ongoing trials with the company’s drug enrolling or treating patients.

According to the representative of Pfizer, Inc, MacKay Jimeson in a telephone interview, the regulators were looking at all of the nerve-factor drugs. In addition, Jimeson said that the development program remained on hold. Pfizer is said to be already preparing a response and looking at the data gathered from 15 studies with tanezumab.