FDA Ends Pain Drug Trials Over Bone Damage Concerns

Johnson & Johnson and AstraZeneca Plc stopped their studies of <"https://www.yourlawyer.com/practice_areas/defective_drugs">experimental painkillers—anti-nerve growth factors (NGF inhibitors)—due to issues that the drug class involved might raise the risk of joint damage, wrote Bloomberg.com.

Last week, the U.S. Food and Drug Administration (FDA) advised Johnson & Johnson that the development program for its painkiller, fulranumab, was being suspended, said Jeffrey Leebaw, a Johnson & Johnson spokesman, wrote Bloomberg.com. AstraZeneca said it stopped its early-stage research of a medication similar to fulranumab, said Bloomberg.com. Also, Regeneron Pharmaceuticals Inc. said that the agency stopped its trials of its medication in the class, added Bloomberg.com. Pfizer Inc. suspended trials of its pain medication, tanezumab, this June following reports that patients in one of its studies required joint replacements.

According to Ziad Bakri, an analyst with Cowen & Co., NGF inhibitors are “a tainted class”; investor expectations have dropped as a result, wrote Bloomberg.com. “You’d have to have a lot of safety data to ever get a drug like this approved, so, for investors, this is not a class that’s generating very high hopes,” Bakri said in a telephone interview, quoted Bloomberg.com. “You’re not going to see many companies chasing these drugs at this point,” Bakri added.

AstraZeneca stopped its studies on medi578, its nerve inhibitor, said Janet Milton-Edwards, a company spokeswoman, wrote Bloomberg.com. Its move was not prompted by regulators and AstraZeneca said it has not seen other cases involving bone tissue death. The firm is “evaluating how we will go forward” with the research, said Milton-Edwards, quoted Bloomberg.com.

The FDA said it was concerned the medications might lead to “rapidly progressive osteoarthritis,” a deterioration of the cartilage that protects bone joints, or osteonecrosis, death of bone tissue due to insufficient blood supply, explained Bloomberg.com. In severe cases, said Drug Watch, patients may require total joint replacement.

Drug Watch explained that NGF inhibitors—a comparatively new drug modality—block the effects of nerve growth factor, which has to do with feeling pain.

According to Bloomberg.com, tanezumab potentially worked so well that it increased joint issues in some patients by minimizing pain that could have indicated to those patients that they were overusing their vulnerable bones, said researchers. That study, which was published in the New England Journal of Medicine, stated that 16 of 6,800 patients required knee, hip, or shoulder joints replacement.

Regeneron said in its recent regulatory filing that the FDA stopped its study of REGN475/SAR164877, after a case of avascular necrosis, or bone-tissue damage, occurred in a different trial, said Bloomberg.com. According to the filing, no ongoing trials with the Regeneron drug that involve enrollment or treatment of patients is taking place, wrote Bloomberg.com. Bloomberg.com explained that avascular necrosis takes place when bones do not receive sufficient blood and oxygen, citing the Mayo Clinic.

Pfizer’s program is on hold, and Pfizer is in the process of developing a response and is looking at the information from 15 studies involving tanezumab, said MacKay Jimeson, a spokesman for the company.

Abbott Laboratories is studying another nerve-growth inhibitor and said it has not heard from the agency, according to its spokeswoman, Tracy Sorrentino, who also said that its study of ABT-110, is “proceeding as planned,” quoted Bloomberg.com.