Amgen Inc revealed on Friday that their new osteoporosis drug denosumab
increased bone density in women receiving therapy with estrogen-depleting
breast cancer drugs known as aromatase inhibitors.
Loss of bone mass with Aromatase Inhibitor therapy is often treated with bisphosphonates.
Researchers at the Seattle Cancer Care Alliance announced they had just
completed a phase 3 clinical trial of the new drug denosumab, also referred to,
as D-mab, and the results looked promising. They said that D-mab increased bone
density resulted from Aromatase Inhibitor therapy or breast cancer drugs that
block the enzyme that affect 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, according to Reuters.
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.
If approved for osteoporosis and cancer patients, D-mab could earn almost $2
billion in annual sales, according to some analysts.
The results of the study supported by Amgen were presented at the San Antonio
Breast Cancer Symposium.
