Subjects: R and D
Zoledronic acid, the intravenous biphosphonate normally used to reduce bone loss in middle-aged and elderly women, reduces by 36% the risk of recurrent or metastatic disease in some women with breast cancer.
To reach this conclusion, Michael Gnant and colleagues at Medical University of Vienna randomized 1,803 premenopausal women with endocrine-responsive, early-stage breast cancer to receive either standard therapy with ovarian suppression plus tamoxifen or the same regimen plus zoledronic acid.
Patients were followed for a median of 4 years.
In that time, 54 women in the treatment group and 83 women in the control group experienced a recurrence in the opposite breast or a bone metastasis.
Other studies of the matter are nearing completion, so James Ingle, the Mayo Clinic’s head of breast cancer research told the New York Times, “it’s a reason for real enthusiasm, but for now…we are not ready to make this a standard treatment.”
But Marc Lippman had a different opinion. The breast cancer specialist and chairman of medicine at the University of Miami said that many women receiving standard treatments for breast cancer already take biphosphonates to counteract the bone-depleting effects of the therapy itself.
So why not just give them zoledronic acid? “I think you have to give it,” he told the Times.
Lab and animal studies have shown that bone-building biphosphonates have many anti-cancer effects. They suppress the activity of osteoclasts for example, and when these cells are active they stimulate cancer cell growth in bone tissue.
The bone-builders also appear to prevent malignant cells from generating their own blood supply, invading other tissues and replicating. They even kill cancer cells directly, at least in laboratory studies.
Novartis markets zoledronic acid using the brand names Zometa and Reclast.