Amgen LogoAmgen has revealed that their new osteoporosis drug denosumab increased bone density in women receiving therapy with estrogen-depleting breast cancer drugs known as aromastase inhibitors.

In fact, loss of bone mass with Aromastase Inhibitor therapy is often treated with bisphosphonates.

Researchers at the Seattle Cancer Care Alliance announced that they had just completed a phase 3 clinical trial of the new drug denosumab, also referred to as D-mab. The results looked promising.

They said that D-mab increased bone density resulted from Aromastase Inhibitor therapy of breast cancer drugs that block the enzyme that effects estrogen in postmenopausal women.

The study led by Georgiana Ellis, MD, of the Seattle Cancer Care Alliance, included 252 participants half of whom were treated with D-mab, delivered subcutaneously twice a year. All the patients in both groups took 1,000 mg of calcium and 400 or more units of vitamin D on a daily basis.

The participants were followed for 2 years. All the patients had the density of the bones in the lumbar spine evaluated at the end of year one and year two. The findings showed that those who had received the treatment with D-mab had their bone density increase by almost 5 percent after the first year of treatment, while those who did not get the treatment had a loss of density of close to 1 percent.

After two years, those who had received the treatment had increased their bone density by close to 6 percent, while in the other group, the bone density had decreased by close to 2 percent.

The researchers concluded that D-mab seemed to be both safe and effective in preventing bone loss.

“In this study, denosumab data looks promising and, as a clinician, I look forward to having a potential alternative to existing therapies,” said Ellis.

The researchers also found a 3.7 percent difference from placebo in total hipbone density and femoral neck bone density, Dr. Ellis said.

“It is clearly going to be useful for patients who have difficulties with Bisphosphonates,” she added.