Apalutamide: the established and emerging roles in the treatment of advanced prostate cancer.

INTRODUCTION: Prostate cancer (PCa) is the most common cancer in elderly males. Androgen deprivation therapy (ADT) is still the cornerstone of initial treatment; however, the vast majority of patients develop castration-resistant prostate cancer (CRPC). Several studies with numerous androgen receptor (AR)-directed agents have emerged since the approval of abiraterone acetate and enzalutamide. One of these agents is apalutamide, which seems to be a promising AR antagonist for the treatment of CRPC. Areas covered: The authors review Phase I, II, and III studies for apalutamide, in a large spectrum of PCa (from low-risk to metastatic CRPC [mCRPC]) patients as sole treatment or in the setting of combined therapy. Expert opinion: Apalutamide is an oral, investigational, AR antagonist that targets the AR ligand-binding domain and prevents AR nuclear translocation, DNA binding, and transcription of AR gene targets. It has shown favorable safety profile and therapeutic index in Phase I studies, good tolerance and efficacy in patients with high-risk CRPC in Phase II studies. Also, results were promising in a recent phase III study in patients with non-mCRPC who were at high risk for the development of metastasis. These data may offer potential advantages over the second-generation antiandrogens.