On March 9, 2018, the European Medicines Agency (EMA) has recommended contraindicating the use of the prostate cancer medicine Xofigo (radium-223 dichloride) with Zytiga (abiraterone acetate) and prednisone/prednisolone, due to an increased risk of death and fractures with this combination.

EMA’s Pharmacovigilance Risk Assessment Committee (PRAC) has reviewed the preliminary data from an ongoing clinical study in metastatic prostate cancer patients. In this study 34.7% of patients treated with Xofigo, Zytiga, and prednisone/prednisolone have died so far, compared with 28.2% of patients given placebo, Zytiga, and prednisone/prednisolone.

Fractures have also occurred more frequently with the Xofigo combination than the placebo combination (26% vs 8.1%).

In view of the seriousness of the events reported, the PRAC has taken action by introducing a contraindication as a temporary measure to protect patients’ safety while an in-depth review of the benefits and risks of Xofigo is ongoing.

Xofigo is currently authorized for use in men whose prostate cancer has spread to the bones and is causing symptoms. The ongoing clinical study includes metastatic prostate cancer patients who have not previously received chemotherapy and who have no symptoms or only mild symptoms, such as pain. Patients have completed the Xofigo part of the study, and the combination is no longer being used; all the patients involved are being monitored closely.

Health-care professionals in the EU must not use a combination of Xofigo with the anti-androgen Zytiga and prednisone/prednisolone, and should stop this combination in men currently treated with it and review the treatment for these patients.

Both medicines can continue to be used separately, in line with the recommendations in their product information.

Health-care professionals are also warned that the safety and efficacy of Xofigo in combination with a class of second-generation androgen-receptor antagonists, such as Xtandi (enzalutamide), have not been established.

These are temporary measures until the ongoing in-depth review of the benefits and risks of Xofigo is complete. EMA will communicate further at the conclusion of the review.

The ongoing study of Xofigo in combination with Zytiga and prednisone/prednisolone included patients with castration-resistant prostate cancer that has spread mainly to the bones, who have no symptoms or only mild symptoms, and who have not been treated with chemotherapy.

Xofigo was authorized in the European Union in November 2013.