The FDA approved 2 new indications for denosumab (Prolia, Amgen) for treating patients at high risk for therapy-induced bone fracture. The first indication is for increasing bone mineral density (BMD) in men receiving an dro gen-deprivation therapy for nonmetastatic prostate cancer; the second is for increasing BMD in women receiving adjuvant aromatase inhibitor therapy for breast cancer.
The approval was based on 2 international randomized, placebo-controlled trials, one involving 1468 men with prostate cancer, the other including 252 women with breast cancer.
At 24 months, BMD in the lumbar spine increased by 5.6% in men who received denosumab but decreased by 1% in those receiving placebo (P <.001). At 36 months, only 1.5% of the men receiving denosumab had new vertebral fractures versus 3.9% in the placebo group (P = .012).
In the women’s study, at 12 months lumbar spine BMD increased by 4.8% with denosumab and decreased by 0.7% with placebo (P <.001).
In both studies, the most common adverse events with denosumab were arthralgia and back pain. Extremity and musculoskeletal pain were also observed. Hypocalcemia, associated only with denosumab, was reported in 2.4% of patients after 1 month of therapy.
Denosumab is already approved for the treatment of osteoporosis in postmenopausal women at high risk for fracture and for the prevention of skeletal-related events in patients with bone metastases from solid tumors. (September 16, 2011)
