Bayer files prostate cancer drug darolutamide in Japan

Bayer has filed its prostate cancer drug darolutamide with Japanese regulators, in an attempt to ratchet up the pressure on rivals Johnson & Johnson and Pfizer/Astellas.

With darolutamide, developed in partnership with Finland’s Orion Corporation, Bayer is hoping to take market share from J&J’s Erleada (apalutamide) and Pfizer/Astellas’ Xtandi (enzalutamide), which have become standard therapies at several different stages of the disease.

Bayer has already filed darolutamide with the FDA, and has followed this up with a filing in Japan in castration-resistant prostate cancer.

The German pharma is also in discussions with other regulators such as the European Medicines Agency (EMA) about a filing.

Bayer and Orion think that their drug may have a safety advantage over their rivals and is tipped to break through the billion-euro annual sales barrier if approved.

However, while analysts think that the side effect profile is favourable based on trial data so far, efficacy is comparable and this may not be enough to win over prescribers looking for an improvement on established therapies.

The filing is based on data from the phase 3 ARAMIS trial in men with non-metastatic disease, which showed a statistically significant improvement in metastasis-free survival for darolutamide plus androgen deprivation therapy (ADT).

In Aramis, 1,509 patients were randomised in a 2:1 ratio to receive 600 mg of darolutamide twice a day or placebo along with ADT.

Bayer is also developing darolutamide in metastatic hormone-sensitive prostate cancer, where the phase 3 prostate cancer trial ARASENS is testing its safety and efficacy.

Scott Fields, senior vice president and head of oncology development at Bayer’s Pharmaceutical Division, said: “In the early stage of prostate cancer, patients are typically asymptomatic.

“Thus, it is critically important for men to have treatment options that significantly delay the development of metastases while limiting burdensome side effects of therapy, which allow them to continue their day-to-day lives.”