Regulators consider withdrawing strontium ranelate over CV safety concerns

Medicines regulators are considering whether the osteoporosis drug strontium ranelate should be withdrawn, after being advised the drug should no longer be prescribed for the condition due to concerns over its cardiovascular safety.

European Medicines Agency (EMA) advisors recently concluded the risks of cardiovascular complications with strontium ranelate outweighed its benefits and recommended the drug should be suspended.

The EMA was due to make a final decision about whether strontium ranelate should now be withdrawn from the market at the end of January, but has put off decision until its committee on medicinal products for human use (CHMP) meets again in February, with the final decision to be announced on 21 February.

The latest news follows months of uncertainty over prescribing strontium ranelate, after concerns over a potential cardiovascular risk first emerged in April last year.

At that time the MHRA advised GPs to restrict use of strontium ranelate to the treatment of severe osteoporosis only and to carry out cardiovascular risk assessments before prescribing it to patients.

But the EMA’s Pharmacovigilance Risk Assessment Committee (PRAC) questioned how far this would reduce users’ cardiovascular risk and the practicality of the restrictions.

The committee’s review found that for every 1,000 patient-years of treatment with strontium ranelate there were four additional serious heart problems and four more cases of thromboses, whereas the drug had only a ‘modest’ benefit in terms of fracture prevention, preventing around five non-spinal fractures, 15 new spinal fractures and 0.4 hip fractures for every 1,000 patient-years.

The PRAC therefore recommended the drug ‘be suspended until there are new data showing a favourable balance in a defined group’.

The EMA said in a statement: ‘The recommendation of the Pharmacovigilance Risk Assessment Committee (PRAC) that Protelos and Osseor should no longer be used to treat osteoporosis is still under consideration by the CHMP.

‘At its January 2014 meeting the committee requested additional information from the company to inform its scientific decision-making. A final opinion will be made by the CHMP at its meeting in February 2014.’

Dr Jonathan Bayly, visiting fellow for osteoporosis and falls prevention at the University of Derby and a former GP in Gloucestershire, told Pulse it would be ‘a shame’ if strontium ranelate was withdrawn, but that there are now more effective alternatives to try second-line to bisphosphonates.

Dr Bayly said: ‘It’s a shame because it was a useful alternative but in terms of our therapeutic options, we now have other ways to go – with increasing experience of iv bisphosphonates and the slightly better data based on RCTs for primary endpoints with denosumab.’

Dr Sally Hope, a former GP and honorary research fellow in women’s health at Oxford University, said: ‘I’m rather saddened by the news as it was a useful alternative drug for patients who simply couldn’t take an oral bisphosphonate, and couldn’t under NICE guidelines obtain funding for teriparatide, or get iv zolendronate.’

A spokesperson for Servier, the manufacturer of Protelos, said: ‘Servier is informing all health agencies in countries where strontium ranelate is registered of the pending proceedings. As soon as this procedure of re-evaluation is finalised, Servier will send detailed information to healthcare professionals specifying the CHMP decision and the practical implications for the management of their patients.’

This story was amended on 4 February to correct the date of the final CHMP decision on strontium ranelate.