Intensification approaches and treatment sequencing in metastatic castration-resistant prostate cancer: a systematic review

Abstract

BACKGROUND AND OBJECTIVE: Recently, research on treatment intensification has gathered momentum, and three novel therapy combinations were approved for metastatic castration-resistant prostate cancer (mCRPC). This systematic review summarizes the current and emerging evidence around intensified strategies for mCRPC and provides guidance for an ideal therapeutic sequencing. METHODS: Preferred Reporting Items for Systematic Review and Meta-analysis Protocols (PRISMA-P) guidelines were followed to perform this review. PubMed, EMBASE, Web of Science, Cochrane Library, ClinicalTrials.gov, and major international societies' online proceedings were searched comprehensively until May 15, 2024, for terms related to treatment intensification and sequencing for mCRPC. KEY FINDINGS AND LIMITATIONS: Overall, 28 clinical trials and 24 ongoing studies of intensification treatments were included in this review. Algorithms of optimal sequencing of approved treatments for mCRPC were outlined according to the use of androgen receptor pathway inhibitors (ARPIs) with or without docetaxel for earlier disease states. In first line, poly(ADP-ribose) polymerase inhibitor + ARPI combinations improve radiographical progression-free survival (rPFS), particularly for those with BRCA1/2 alterations. The AKT inhibitor combination of ipatasertib + abiraterone extends rPFS in those with PTEN loss or PIK3CA/AKT1/PTEN alterations. In those with two or more risk factors for early progression on enzalutamide, radionuclide 177-Lu-PSMA-617 + enzalutamide prolongs progression-free survival. Ongoing research of intensified approaches for mCRPC, and available and potential predictive and prognostic biomarkers are discussed. CONCLUSIONS AND CLINICAL IMPLICATIONS: Recent approvals and ongoing investigations of single agents and intensification approaches will keep transforming the mCRPC treatment landscape. Improvement of patient profiling applying recognized genomic, molecular, and clinical predictive and prognostic indicators is fundamental to optimize sequential use of available therapies.