Predictive biomarkers of response are required for the evaluation of patients with metastatic castration-resistant prostate cancer treated with a sequential regimen

Giandomenico Roviello

Medical Oncology Unit, University of Siena, Policlinico Le Scotte, Viale Bracci 11, 53100 Siena, Italy.

E-mail: giandomenicoroviello@hotmail.it; Fax: +390577586139

Accepted 09 October, 2013

Abstract

Schrader et al analyzed the effects of the sequential regimen, Abiraterone Acetate (AA) followed by Enzalutamide (E). Their data showed that E is only moderately effective after AA failure. However, a significant biochemical response (>50% PSA decline) to E was observed only in some patients who had previously achieved a >50% PSA decline with AA treatment. Then, cross-resistance between AA and E seems to be a common event and in some cases OS achieved in patients after Docetaxel failure is even longer when they are treated with AA or E only rather than when a sequential strategy with these two agents is undertaken. However, a subset of these patients who underwent a sequential therapy has shown benefits in terms of OS. Therefore, the development of predictive biomarkers of response is required in order to tailor the new therapeutic agents to the biology of the cancer and to obtain max OS.

Keywords: Abiraterone Acetate, Enzalutamide, Sequential regimen, Cross-resistance