Regarding this confirmatory analysis presented by Ryan et al at the ESMO 2014 Congress, formal discussant Bertrand Tombal, MD, PhD, Chairman of the Division of Urology and Associated Professor of Physiology at Université Catholique de Louvain, Brussels, said, “COU-AA-302 profoundly impacted the way we treat patients. The final analysis is important. In Europe, some of us don’t have [abiraterone], and hopefully these data will speed up reimbursement for [the drug] in the predocetaxel space.”

He noted, “The study showed a disproportionate benefit for progression-free survival [compared with] overall survival. This is a problem for some people, but not for me.”

Regarding the primary endpoint, he pointed out that progression-free survival is a regulatory requirement. “But when you treat patients, the most important benefit is to improve their outcome. Keep that in mind,” he told the audience.

Significance of Crossover

Because of the crossover, COU-AA-302 is really a study of early vs delayed hormone therapy. “To me, the benefit of giving the patient earlier is the most important question. Delaying treatment has a major impact on time to chemotherapy, and on patient-reported outcomes such as pain and quality of life,” he said.

“By introducing earlier hormone therapy, we influence the time of progression, and change the impact on the patient, but we don’t improve overall survival. I believe we should disregard the fact that the benefit for progression-free survival is stronger than that for overall survival. Abiraterone has many other benefits, and the trial is really about early vs delayed therapy,” he said. ■

Disclosure: Dr. Tombal is a paid advisor or investigator for Amgen, Astellas, Bayer, Medivation, Ferring, Janssen, and Sanofi-Aventis.