Pfizer has been asked by the FDA to suspend chronic pain studies involving tanezumab because of safety concerns. The investigational compound had been touted by some as a potential blockbuster.

Tanezumab’s problems began last month when an osteoarthritis clinical trial was halted following reports that some patients’ osteoarthritis had worsened, necessitating joint replacement. In its 

, Pfizer claimed that the adverse event had not been observed in non-osteoarthritis patient populations. 

However, the FDA has further considered the reports and is concerned that there is potential for such events to occur in other patient populations in which the compound is being studied. As such, Pfizer has 

 its tanezumab studies for chronic low back pain and painful diabetic peripheral neuropathy, although it will continue investigation of the compound in some areas of high unmet medical need, such as cancer pain. 

Pfizer has been asked by the FDA to suspend chronic pain studies involving tanezumab because of safety concerns.