EU Panel Recommends Suspension of Protelos/Osseor

Miriam E. Tucker

January 10, 2014

The European Medicines Agency's Pharmacovigilance Risk Assessment Committee (PRAC) has recommended that strontium ranelate (Protelos/Osseor, Servier) no longer be used to treat osteoporosis.

The decision comes after an in-depth analysis, which led the panel to determine that the drug's risks outweigh its benefits.

Strontium ranelate has been approved in Europe since 2004 for the treatment of osteoporosis to reduce the risk for vertebral and hip fractures in postmenopausal women. In 2012 the indication was expanded to include men at increased risk for fracture. It is not currently approved in the United States.

But in April 2013, the PRAC advised restrictions on use of the product, and those restrictions were endorsed by the Agency's Committee for Medicinal Products for Human Use (CHMP).

After further examination of the data, the PRAC noted that there were 4 or more cases of both cardiac events and thromboembolism with strontium ranelate for every 1000 patient-years compared with placebo. Moreover, the drug is also associated with other adverse events, including serious skin reactions, disturbances in consciousness, seizures, liver inflammation, and reduced numbers of red blood cells.

The panel also expressed doubts about the extent to which the April 2013 restrictions were being followed, considering that the product is used long term in the elderly.

And, although strontium ranelate does prevent about 5 nonspinal fractures, 15 spinal fractures, and 0.4 hip fracture for every 1000 patient-years, the committee decided that these benefits did not outweigh the potential risks and therefore the product's use should be suspended until further data support a benefit in a defined patient group.

The PRAC recommendation will now be sent to CHMP, which is expected to issue the Agency's final opinion at its meeting on January 20 to 23, 2014.