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

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.