Bayer HealthCare has started patient enrolment in a new Phase III trial of radium-223 dichloride (radium-223, Xofigo) in combination with abiraterone acetate and prednisone/prednisolone to treat asymptomatic or mildly symptomatic chemotherapy-naïve patients with bone predominant metastatic castration-resistant prostate cancer (CRPC).
The randomised double-blind, placebo-controlled Phase III trial is designed to determine the effects of the combination treatment on symptomatic skeletal event-free survival (SSE-FS).
In the EU, radium-223 has been approved under the brand name Xofigo to treat adults with CRPC, symptomatic bone metastases and no known visceral metastases.
In the US, radium-223 is approved for the treatment of CRPC patients with symptomatic bone metastases and no known visceral metastatic disease.
Bayer HealthCare member of the executive committee and head of global development Joerg Moeller said radium-223 has a specific mode of action and has already showed safety and efficacy in CRPC patients with symptomatic bone metastases and no known visceral metastases.
"We welcome further exploration of treatment combinations and pathways that may extend these benefits in even more men with this disease as the treatment landscape continues to evolve rapidly," Moeller said.
The Phase III trial will investigate whether providing radium-223 dichloride (radium-223) in combination with abiraterone acetate and prednisone/prednisolone will increase symptomatic skeletal event free survival (SSE-FS).
Around 800 patients will be enrolled in the trial and will be randomised in a 1:1 ratio to receive either radium-223 dichloride or placebo in addition to abiraterone acetate plus prednisone/prednisolone and best supportive care for the first six cycles followed by abiraterone acetate plus prednisone/prednisolone thereafter until an on-study symptomatic skeletal event (SSE) occurs.
The trial will be sponsored by Bayer and carried out in collaboration with Janssen Research and Development in several regions including sites in Europe, the US, Australia, Brazil and Japan.
Janssen Pharmaceutical's product, abiraterone acetate, is a prescription medicine that is used along with prednisone and is available in over 80 countries.
The company said that abiraterone acetate is the pro-drug of abiraterone that works by inhibiting the CYP17 enzyme complex in the androgen biosynthesis pathway which is essential in the production of testosterone and other androgens.
Image: Micrograph of prostate adenocarcinoma, acinar type, the most common type of prostate cancer. Photo: courtesy of Nephron.