For post-menopausal women with hormone receptor positive breast cancer, the standard of care has been adjuvant hormone therapy with a group of drugs called Aromatase inhibitors, including Letrozole and Anastrazole. Unfortunately, a side effect of these drugs is compromised bone health that can lead to osteopenia, osteoporosis, and bone fractures.
Michael Gnant, MD, and colleagues at the Comprehensive Cancer Center at the Medical University of Vienna conducted a phase III clinical trial to investigate the use of Denosumab, a bone protective agent, for women with early-stage, hormone receptor-positive breast cancer who are receiving adjuvant aromatase inhibitor therapy.
The original findings of this study, published in 2015, showed that Denosumab reduced the risk of bone fractures in these patients by 50%. An update on this study was presented at the American Society of Clinical Oncology Annual Meeting in Chicago this June 2018, which reported the effect of adjuvant Denosumab on disease-free survival.
There were 3,425 women enrolled in the trial. Half the group received 60 mg of Denosumab every six months, while half received a placebo. These are simple treatments, administered as a subcutaneous injection. It was found that Denosumab reduced the risk of cancer recurrence and death in these women. The benefit was greatest in women who had larger tumors and who initiated the therapy early on. This group of women did 10% better in terms of disease-free survival at 7 years.
With a dramatic reduction of clinically relevant fractures and improvement in disease-free survival, adjuvant Denosumab is a promising treatment option. I am excited to see potential treatments such as this that improve patient outcomes and quality of life during and after treatment.
*Adjuvant therapy is additional treatment given after definitive treatment is complete.