Denosumab treatment in HR+ breast cancer

This study wanted to find out if adding the medication denosumab (Prolia, Xgeva) to cancer treatment for women with breast cancer reduces the risk of bone fractures. The study found that the patients treated with denosumab survived better, but there was no significant difference in the number of bone fractures.

Breast cancer cells can have certain receptors on their surface. These hormone receptors can be used to target the cancer cells and kill them. Aromatase inhibitors are a kind of medication that can treat hormone receptor positive breast cancer. A side effect of taking aromatase inhibitors is that the bones can become weak and break easily. Denosumab is a type of anticancer medication. It is not known if adding denosumab to treatment will decrease the risk of bone fractures in patients with breast cancer being treated with aromatase inhibitors.

This study had 3425 patients. All of the patients were treated with aromatase inhibitors. 1711 of these patients were treated with denosumab as well. The remaining 1709 patients took a placebo medication. Patients were followed for 73 months after treatment.

After 5 years, 89.2% of the patients who took denosumab were still alive. After 5 years, 87.3% of the patients who took the placebo were still alive. After 8 years, 80.6% of the patients who took denosumab were still alive. After 8 years, 77.5% of the patients who took the placebo were still alive.  Overall, 14% of the patients who took denosumab had side effects. 16.8% of patients who took the placebo pill had side effects. The most common side effects were arthritis of the bone (osteoarthritis). Osteoarthritis was a side effect of treatment in 3.6% of the patients who took denosumab. Osteoarthritis was a side effect of treatment in 3.4% of the patients who took the placebo.

The study concluded that adding denosumab to aromatase treatment in patients with hormone receptor positive breast cancer increases survival.

This is a large study. It enrolled patients at the beginning and followed them through time. It was the third trial in a series of three to identify how well this medication works.

Talk to your doctor about your treatment plan.