Khalaf DJ, Annala M, Taavitsainen S, et al. - In this multicentre, randomized, open-label, phase 2, crossover trial conducted in six cancer centers in British Columbia, Canada, of 202 individuals aged 18 years or older with newly-diagnosed metastatic castration-resistant prostate cancer without neuroendocrine differentiation and Eastern Cooperative Oncology Group performance status 2 or less, experts ascertained the best sequence in which to use both drugs (abiraterone acetate plus prednisone and enzalutamide), as well as their second-line efficiency for the treatment of metastatic castration-resistant prostate cancer. Compared with the opposite treatment sequence, enzalutamide exhibited activity as a second-line novel androgen receptor pathway inhibitor, whilst abiraterone acetate did not, resulting in a prolonged time to second PSA progression for the sequence of abiraterone followed by enzalutamide. Results imply that the highest clinical advantage is obtained using a sequencing approach of abiraterone acetate followed by enzalutamide.