There has been a report stating that an experimental pain drug can be associated with serious bone disorder, that is why the U.S. Food and Drug Administration and Johnson & Johnson halted studies and its release.

It was the FDA that advised Johnson & Johnson that the drug fulranumab and other types of pain drugs known as nerve growth factor inhibitors (NGF) could be connected with a condition that may lead to a total joint replacement.

Jeffrey Leebaw, the spokesman for J&J stated in an email that they are closely working with FDA to resolve such issues. Other companies involved include Regeneron Pharmaceuticals Inc, with their anti-NGF drug for osteoarthritis called REGN475/SAR164877. FDA halted the production of these specific Regeneron drugs and that of J&J because of a report that a patient in another company’s trial was diagnosed with avascular necrosis of a joint.

Avascular necrosis happens when the bone tissues die because of lack of blood supply. This will lead to bone collapse later.

Regeneron is trying to develop their pain drug with Sanofi-Aventis SA. Their drug is similar to that of J&J’s product which is designed to block NGF, a pain-associated protein. Pfizer’s own version of anti-NGF has already been put on hold early this year when some patients reportedly needed to have joint replacement surgery. This was despite the fact that Pfizer’s drug tanezumab was considered as the most advanced in the class.

Before FDA has given the company a word, AstraZeneca Plc has already voluntarily halted their studies of their own NGF-inhibitor named MEDI-578.