A major trial that aimed to see if a common bone-strengthening drug could help prevent recurrences of breast cancer found it did not benefit most patients, doctors said Thursday.
The five-year study, known as the AZURE trial, followed 3,360 women with advanced breast cancer who had already undergone surgery.
The study randomly assigned some to take the osteoporosis drug Zometa, also known as zoledronic acid, in addition to standard therapy. Zometa is made by the Swiss pharmaceutical giant Novartis.
The hope was that it would prevent cancer from resurfacing, as it often does, in a survivor's bones.
But the American Association for Cancer Research said the drug was found to have no impact on "disease-free survival" for the group as a whole.
"In the larger population, we did not see a difference," said Robert Coleman, professor of medical oncology at the University of Sheffield in England, who presented the results at a conference in San Antonio, Texas.
He added, however, that there was a slight difference across age groups, with older patients faring slightly better on the drug.
The 30 percent of the group who were post-menopausal by at least five years, 1,101 in all, saw a 29 percent improvement in overall survival, which was "unlikely to be a chance finding," Coleman said.
"We will clearly want to investigate further in this population."
He added, however, that "the young patients are getting no benefit. If anything they are doing worse."
Zoledronic acid is a bisphosphonate that works by lowering the amount of calcium released by the bones into the blood.
It is used to treat high blood calcium levels that can coincide with cancer and also to prevent fractures in patients with cancer.