Osteoporosis drug may double as pain reliever for metastasized prostate cancer

While bisphosphonates are currently prescribed as a treatment for osteoporosis, one variety of the medication may soon be repurposed as a pain reliever for prostate cancer patients with bone metastases.

A group of UK researchers made this announcement at the 2011 European Multidisciplinary Cancer Congress in Stockholm, Sweden.

Led by Peter Hoskin of University College, London, the team said that a single shot of ibandronate - a bisphosphonate known in the U.S. by the brand name Boniva - appears to reduce pain caused by skeletal metastases of prostate cancer, at least as well as a single dose of radiation therapy.

With few serious side effects, the drug reduced the aches of such tumors among men who had poor general prognoses.

The average survival time for a participant with metastatic prostate cancer was between 12 and 16 months, giving ibandronate the potential to be a palliative therapy, researchers noted.

How is an osteoporosis medication relevant to bone pain caused by extensive prostate cancer? The key is skeletal weakening. The Bone and Cancer Foundation notes that the two primary symptoms of skeletal metastases of prostate carcinoma are intense pain and weakened bones.

Distant prostate cancer growths can weaken the skeleton and lead to fractures, the organization states, adding that bisphosphonates appear to be one effective treatment for this problem.

When it comes to the prevalence of osteoporosis and of prostate cancer, the numbers are quite similar. Roughly 2 million men currently have osteoporosis, according to the National Osteoporosis Foundation (NOF).

Compare prostate cancer, of which the National Cancer Institute estimates 2.3 million living men have a history.

The research team concluded that their discovery lengthens the list of therapies available to patients with the serious disease.

"Our research adds to the arsenal of the many effective treatments now available, and we believe that the findings will also be applicable to other primary cancers that can lead to bone metastases," they said.

For osteoporosis, ibandronate is usually prescribed either as a monthly oral tablet or as an injection taken four times a year, the NOF notes.