EU Panel Recommends Suspending Use of Strontium Ranelate for Osteoporosis

Strontium ranelate (marketed as Protelos® or Osseor®) is a medicine used in other parts of the world, but it is not approved for use in the US. Nevertheless, some patients in the US end up seeking sources for this medicine as alternatives to the current FDA-approved drugs for osteoporosis and may be taking this medicine. Strontium ranelate is authorized in the European Union to treat severe osteoporosis in women who have been through the menopause and and men who are at high risk of broken bones or fracture in the spine and the hip.

A committee of the European Medicines Agency, the European equivalent to our FDA, recommended suspending strontium ranelate (Protelos/Osseor) for treatment of osteoporosis. After an in-depth review by their Pharmacovigilance Risk Assessment Committee, they concluded the risks of strontium ranelate outweighed its benefits and recommended it no longer be used to treat osteoporosis. A final opinion will be issued after review later this month.

What are the Risks Associated with Strontium Ranelate?

Heart problems, blood clots, and more risks were identified. Last year the agency recommended restricting the use of strontium ranelate because of risk of heart problems found on a routine benefit-risk assessment.

To follow up on this signal of possible problems with strontium ranelate, the Agency conducted an in-depth review of data on the benefits and risks of the medicine. The assigned Committee noted that for every 1,000 patients being treated for 1 year, there were 4 more cases of serious heart problems (including heart attacks) and 4 more cases of blood clots or blockages of blood vessels with strontium ranelate than with placebo (dummy treatment). In addition, the medicine was associated with previously reported serious skin reactions, disturbances in consciousness, seizures , liver inflammation, and reduced number of blood cells.

On the benefit side, the effectiveness of osteoporosis medicines are evaluated by reducing the number of fractures. Strontium ranelate have a modest effect in osteoporosis, preventing about 5 non-spinal fractures, 15 new spinal fractures and 0.4 hip fractures in 1,000 patients being treated for 1 year.

Conclusion: Risks Outweigh Benefits of Strontium Ranelate

The Committee weighed the benefits of strontium ranelate against the known risks and concluded that the balance was no longer favorable and recommended the medicine be suspended until there are new data showing a favorable balance in a defined patient group.

A final opinion on keeping strontium ranelate as an approved medicine for treatment of osteoporosis in the European Union is expected after the Agency’s meeting January 20 to 23, 2014. In the meantime, if you are taking this medicine talk with your doctor about your individual risks.

Diane L. Schneider, MD, MSc
Author, The Complete Book of Bone Health
Medical Editor,