Full results from a Phase III trial of Amgen's Xgeva have demonstrated that the drug is able to delay the progression of prostate cancer into the bone, which could significantly extend its market potential.

The data show that Xgeva (denosumab), which is also marketed as Prolia for the treatment of osteoporosis, significantly improved median bone metastasis-free survival by 4.2 months, a risk reduction of 15%, compared to placebo.

The trial failed to show any survival benefit with Xgeva, but is reportedly the first randomised study to show a significant reduction in the risk of bone metastasis in men with prostate cancer.  

According to Amgen, while effective therapies are in place for both early and advanced prostate cancer, there is still an unmet need for those patients who have advanced disease which has not spread, and given that up to 90% of men with prostate cancer will experience bone metastases the potential market for Xgeva is considerable.

In fact, analysts predict that Xgeva's performance, which is the first and only RANK Ligand inhibitor approved by the US Food and Drug Administration for the prevention of skeletal-related events in patients with bone metastases from solid tumours, could benefit from sales of $1-$2 billion if regulators OK its prevention of bone metastasis in prostate cancer patients, according to media reports.