The Medicines and Healthcare products Regulatory Agency (MHRA) has approved an additional indication for enzalutamide (Xtandi) for adult men with metastatic hormone-sensitive prostate cancer (mHSPC). 

With this, enzalutamide is now the only oral treatment approved by the MHRA to treat three distinct types of advanced prostate cancer. These are: high risk non-metastatic and metastatic castration-resistant prostate cancer (CRPC), as well as mHSPC.

The new treatment has served as welcome news for the sector, as men diagnosed with mHSPC tend to have a poor prognosis, with a median survival of approximately 3-4 years. 

Men diagnosed with mHSPC have a median survival of approximately 3-4 years

The approval from the MHRA came after the results from the pivotal Phase 3 ARCHES trial, which evaluated enzalutamide in men with mHSPC.

Data from the ARCHES trial showed enzalutamide plus androgen deprivation therapy (ADT) significantly reduced the risk of radiographic progression or death by 61% versus placebo plus ADT in men with mHSPC.

Andrew Armstrong, M.D., Professor of Medicine, Surgery, Pharmacology and Cancer Biology and Director of Research in the Duke Cancer Institute’s Centre for Prostate and Urologic Cancers is the lead investigator of ARCHES. He said: "Metastatic hormone-sensitive prostate cancer patients have limited options and, unfortunately, there is a poor prognosis for many men.

“The research supporting this approval provides clinical evidence showing how enzalutamide can help improve outcomes for men with mHSPC, which gives healthcare professionals in Europe the option to offer the treatment across the advanced prostate cancer disease continuum.”

Clinical evidence that enzalutamide can help improve outcomes for men with mHSPC

The safety analyses of the ARCHES trial appear consistent with the safety profile of enzalutamide in previous clinical trials in CRPC. In ARCHES, Grade 3 or greater adverse events (defined as severe/disabling or life-threatening) were similar for patients receiving both enzalutamide plus ADT and those who received placebo plus ADT (24.3% vs. 25.6%).

The MHRA marketing authorisation for enzalutamide in men with mHSPC is applicable in the territory of Great Britain. The approval will have no impact on the financial forecasts of the current fiscal year ending March 31, 2022.