New androgen pathway targeting agents (ARTA), including Abiraterone acetate, Apalutamide and Enzalutamide, are approved and used in treatment of metastatic hormonal sensitive prostate cancer(mHSPC). However, the development of castration-resistance prostate cancer(CRPC) is only a matter of time. The use of sequential ARTAs in mCRPC showed limited benefit in retrospective series and prospective trials. Therefore this sequence should be avoided because of known cross resistance and the availability of chemotherapy and poly adenosine diphosphate-ribose polymerase(PARP) inhibitors (if a relevant mutation is present).

Recently, a randomized controlled trial(RCT), the ABIDO-SOGUG, indicated that compared with docetaxel, maintaining Abiraterone added to docetaxel in chemotherapy-naive patients who have experienced cancer progression to Abiraterone treatment could not improve radiographic progression-free survival or the other endpoints.However, another RCT, the PRESIDE trial, indicated that in patients who had progressed on Enzalutamide, continued Enzalutamide treatment in combination with docetaxel led to a significant improvement of PFS compared with placebo plus docetaxel.

The aims of this trial is to assess both the efficacy and safety of docetaxel in combination with Enzalutamide as first-line treatment in mCRPC patients progressed on Abiraterone.

Inclusion Criteria:

• adenocarcinoma
• mCRPC
• Eastern Cooperative Oncology Group(ECOG) 0-1
• prior Abiraterone treatment

Exclusion Criteria:

• prior Enzalutamide or Docetaxel treatment