FDA panel votes against wider use of denosumab for prostate-cancer patients

An FDA advisory panel recommended against using denosumab (Xgeva, Amgen) to delay or prevent the spread of castration-resistant prostate cancer (CRPC) at high risk for bone metastases. The FDA’s Oncologic Drugs Advisory Committee concluded that the drug offered a statistical benefit but not a clinical benefit.

“The effect of the studied compound is quite weak with no effect on survival or the overall course of the disease,” said panel member Ronald Richardson, MD, assistant professor of oncology, Mayo Clinic, Rochester, Minn.

Amgen presented a phase 3 study in 1,432 men showing a mean delay of 4 months in the development of bone metastases in men with CRPC compared to placebo. The study also found osteonecrosis of the jaw in about 5% of patients taking denosumab.

The panel voted 12-1 against the new indication. The sole vote for approval came from the committee’s consumer member. FDA staff did not directly recommend against approval, but noted that an editorial in The Lancet said the findings “do not support its broad use as a preventive agent for bone metastases in prostate cancer.”

Denosumab was approved in 2010 for the prevention of skeletal-related events in patients with solid tumors, including prostate cancer, metastatic to bone. The same agent was approved for postmenopausal women with osteoporosis at high risk for fracture and for men at high risk for bone fracture following androgen deprivation therapy for nonmetastatic prostate cancer.

“We look forward to further discussions with the FDA as they continue to review our application,” Amgen said in a statement. “The development of bone metastases in men with castration-resistant prostate cancer is a clinically significant event and delaying bone metastases in these men is a clear unmet need with no approved therapies.”