Amgen announced findings from a three-year pivotal phase 3 placebo-controlled trial evaluating denosumab in the treatment of bone loss in men undergoing androgen deprivation therapy (ADT) for non-metastatic prostate cancer.

In this study of more than 1,400 men, denosumab treatment produced statistically significantly greater increases in bone mineral density (BMD) at the lumbar spine (primary endpoint) and non-vertebral sites compared with placebo at multiple time points. These improvements in BMD were consistent with those seen in other denosumab studies evaluating BMD in women with breast cancer receiving aromatase inhibitor therapy, and in post-menopausal women with low bone mass.

During the 36-month evaluation period, men receiving denosumab experienced less than half the incidence of new vertebral fractures (a secondary endpoint) compared with those receiving placebo, a statistically significant finding. Furthermore, in the denosumab arm there were fewer non-vertebral fractures over the 36-month period.

The incidence and types of adverse events observed in this study were generally similar between the denosumab and placebo groups. The most common adverse events across both treatment arms were arthralgia, back pain, constipation, and pain in extremity. Serious adverse infectious events occurred in approximately 5 per cent of men receiving placebo treatment as compared with approximately 6 per cent of those receiving denosumab.