Amgen, a biotech company discovers, develops, manufactures and delivers innovative human therapeutics has received the US Food and Drug Administration (FDA) approval for new indication for Prolia (denosumab) as a treatment to increase bone mass in men with osteoporosis at high risk for fracture. Prolia, the first FDA-approved RANK Ligand inhibitor, is a subcutaneous injection administered by a health care professional every six months.

"While osteoporosis and osteoporosis-related fractures are more commonly associated with post-menopausal women, osteoporosis in men is a significant issue that is increasing in prevalence as life expectancies rise," said Sean E Harper, MD, executive vice president of Research and Development at Amgen. "Fractures can be a life-changing event, so we are pleased that we can offer a new treatment option for the growing number of men with osteoporosis at high risk for fracture."

According to the National Osteoporosis Foundation, two million men in the US have osteoporosis and another 12 million are at risk. Osteoporosis and osteoporotic fractures in men remain under diagnosed and under treated.

The new indication for Prolia is based on results from the ADAMO trial (A multi-centre, randomized, double-blind, placebo-controlled study to compare the efficacy and safety of DenosumAb 60 mg every six months versus placebo in Males with Osteoporosis), the pivotal phase III study involving 242 men with low bone mineral density (BMD). In the study, treatment with Prolia resulted in significantly greater gains at the lumbar spine when compared to placebo (5.7 per cent vs. 0.9 per cent). Effects of Prolia on BMD were independent of age, baseline testosterone levels, BMD status and estimated fracture risk.

Additional results showed that patients in the study who received treatment with Prolia experienced BMD increases at all other skeletal sites assessed compared to placebo, including at the total hip (2.4 per cent vs. 0.3 per cent) and at the femoral neck (2.1 per cent vs. 0.0 per cent). Safety findings were consistent with what have been observed in other studies of Prolia in post-menopausal women with osteoporosis. The most common adverse reactions reported (per patient incidence > 5 per cent) were back pain, arthralgia and nasopharyngitis.

Approval was based on the ADAMO trial 12-month data. Men between the ages of 30 and 85 years with low BMD (T-score =–2.0 and =–3.5 at the lumbar spine or femoral neck) or who have experienced a prior major osteoporotic fracture and had a T-score =–1.0 and =–3.5 were enrolled in the study. Patients were randomized (1:1) to receive either 60 mg of Prolia every six months or placebo. All patients received daily calcium and vitamin D supplementation throughout the study.

The primary study endpoint was the percent change from baseline in the lumbar spine BMD at month 12. Secondary efficacy endpoints included percent change in total hip and femoral neck BMD from baseline to one year.

Osteoporosis in men has recently been recognized as an important public health issue, as male life expectancies rise and the number of men over the age of 70 grows.

Prolia is the first approved therapy that specifically targets RANK Ligand, an essential regulator of osteoclasts (the cells that break down bone).

Prolia is approved in the US for the treatment of post-menopausal women with osteoporosis at high risk for fracture, defined as a history of osteoporotic fracture, or multiple risk factors for fracture; or patients who have failed or are intolerant to other available osteoporosis therapy. Prolia is also approved for treatment to increase bone mass in men with osteoporosis at high risk for fracture, defined as a history of osteoporotic fracture, or multiple risk factors for fracture; or patients who have failed or are intolerant to other available osteoporosis therapy.