Bone drug flops in cancer study

SAN ANTONIO – One of the most promising new approaches for fighting breast cancer took a stunning setback Thursday when a major study showed that a bone-building drug did not stop cancer from returning or extend life for most women fighting the disease.

However, the drug Zometa did seem to help certain post-menopausal women.

“Ten years of work and to have essentially a negative study is disappointing, particularly on a tremendous wave of enthusiasm for this based on some positive trials in the past,” said the study’s leader, Dr. Robert Coleman of the University of Sheffield in England. He presented results at a cancer conference in San Antonio.

Bone drugs called bisphosphonates, sold as Fosamax, Boniva and Actonel, have long been sold for treating osteoporosis. Those are daily pills; Zometa, sold as Reclast for osteoporosis, is given as an infusion twice a year.

Hopes that these drugs could also prevent cancer soared after a study two years ago found Zometa cut the risk of cancer recurrence by 30 percent in younger women forced into early menopause by hormone treatments they received.

The new study was meant to be definitive. It tested Zometa in 3,360 women of all ages in seven countries who had breast cancer that had spread to lymph nodes. All received standard cancer treatments, and half also got periodic infusions of Zometa for five years.

After five years of followup, about 400 women in each group had died or suffered a recurrence.

However, among the roughly 1,100 women who were at least five years past menopause when the study began, Zometa cut the risk of recurrence by about 27 percent and improved survival odds by about 29 percent.

Coleman said it may be that Zometa works best when no or little estrogen is present.