Which switch?

Most men with metastatic, castration resistant prostate cancer (mCRPC) will have seen some sequence of androgen deprivation (ADT), an androgen signaling targeted agent (enzalutamide or abiraterone), and docetaxel. And while outcomes are improving with these regimens, prostate cancer is a pretty nasty disease when it gets beyond this point. But after progressing on an androgen signalling inhibitor and docetaxel, is it better to switch to a different androgen signalling inhibitor or to the next-generation taxane, cabazitaxel? The CARD trial asked just that question. Men with either PSA or clinical progression after receiving some sequence of docetaxel and either abiraterone or enzalutamide were randomized to then receive either cabazitaxel or the alternate androgen signalling inhibitor. Remembering that we’re in the very advanced stage of prostate cancer here, cabazitaxel doubled the primary endpoint of radiographic progression-free survival from 3.7 to 8 months. It also improved overall survival a small but significant 11→ 13.6 months and the PSA response rate from 13.5→ 35.7%. TBL: For men whose mCRPC progresses after both docetaxel and an androgen receptor inhibitor, switching taxanes (to cabazitaxel) as opposed to switching androgen receptor inhibitors provides the most meaningful clinical benefit. | de Wit, N Engl J Med 2019