Servier has suffered a setback after regulators in Europe, "following an in-depth review," said that Protelos should no longer be used to treat osteoporosis.

The European Medicines Agency's Pharmacovigilance Risk Assessment Committee has recommended that Protelos (strontium ranelate), which is also marketed as Osseor, should not be available anymore after "an in-depth analysis" led the panel to determine that the drug's risks outweigh its benefits. It was approved in Europe in 2004 for the treatment of osteoporosis to reduce the risk for vertebral and hip fractures in postmenopausal women and in 2012 the indication was expanded to include men at increased risk for fracture.

Last April, the PRAC recommended restricting use of Protelos but after further review it has noted that for every 1,000 patient-years, there were four more cases of serious heart problems (including heart attacks) and four more cases of blood clots with Protelos than with placebo. In addition, the Servier treatment is associated with a number of other risks, such as serious skin reactions, disturbances in consciousness, seizures, liver inflammation and reduced number of blood cells.

The committee also questioned the evidence "on the extent to which the restrictions recommended in April 2013 reduced the cardiovascular risk and how well the restrictions work in clinical practice", particularly as the medicine is used for long-term treatment in elderly patients. With regard to benefits, the PRAC noted that Protelos has been shown to have "a modest effect in osteoporosis", preventing about five non-spinal fractures, 15 new spinal fractures and 0.4 hip fractures for every 1,000 patient-years.

The panel has therefore recommended that Protelos be suspended "until there are new data showing a favourable balance in a defined patient group". The EMA's Committee for Medicinal Products for Human Use (CHMP) will issue a final opinion at its January 20-23 meeting.

Acknowledging that recent research "highlighted a group of patients who may be at increased risk of cardiovascular events", Servier said that as soon as the EMA's decision is finalised, it will send "detailed information to healthcare professionals with practical implications for the management of their patients".