Protelos and Osseor Under Review by EMA

Lara C. Pullen, PhD


October 21, 2011

October 21, 2011 — The European Medicines Agency (EMA) has begun reviewing cardiovascular and cutaneous toxicity in patients prescribed strontium ranelate (Protelos/Osseor, Les Laboratoires Servier). Protelos and Osseor are indicated for the treatment of postmenopausal osteoporosis to reduce the risk for vertebral and hip fractures.

The drugs were authorized by the European Centralised Procedure on September 21, 2004. The risk for venous thromboembolism (VTE) was identified in clinical trials. In 2007, the EMA noted the risk for severe allergic reaction to Protelos and Osseor and termed it drug rash with eosinophilia and systemic symptoms (DRESS). At that time the EMA's Committee for Medicinal Products for Human Use concluded that a warning on the risks for DRESS should be included in the prescribing information and that patients experiencing DRESS symptoms should stop treatment and contact their physician immediately.

Recently, however, a study analyzing the side effects associated with strontium ranelate spontaneously reported in France from January 2006 to March 2009 to Les Laboratoires Servier or the French competent authority (AFSSAPS) noted 199 severe adverse reactions. Of those, 52% were cardiovascular (most frequently VTE events) and 26% were cutaneous. The authors concluded that DRESS syndrome is unpredictable but that the VTE risk could be reduced by adding a contraindication for patients with a history of VTE and by stopping treatment if a new VTE risk situation occurs. On the basis of a recent pharmacovigilance update and pending a European Union–wide review, AFSSAPS recommended restricting the use of strontium ranelate to patients who are younger than age 80 years, are at high risk for fractures, and cannot take bisphosphonates.

The risks for VTE and DRESS are currently addressed in the EMA risk-management plan and have been kept under close review by the Agency's Committee for Medicinal Products for Human Use. The EMA has now decided, however, to start a review of the strontium ranelate–containing medicine to determine whether the cases of VTE and DRESS affect the benefit-risk profile and conditions of use for Protelos and Osseor.


Comments on Medscape are moderated and should be professional in tone and on topic. You must declare any conflicts of interest related to your comments and responses. Please see our Commenting Guide for further information. We reserve the right to remove posts at our sole discretion.