Real-world outcomes in patients with metastatic castration-resistant prostate cancer receiving second-line chemotherapy versus an alternative androgen receptor-targeted agent (ARTA) following early progression on a first-line ARTA in a US community oncology setting

摘要

ObjectiveThis retrospective observational study assessed if second-line chemotherapy vs. androgen receptor-targeted agents (ARTAs; abiraterone/enzalutamide) is associated with improved outcomes in metastatic castration-resistant prostate cancer (mCRCaP) patients who experience early progression on first-line ARTAs in a US community setting. MethodsPatients with mCRCaP (n?=?345) who progressed ≤ 12 months after first-line ARTA and received second-line chemotherapy (docetaxel/cabazitaxel;n?=?147) or ARTA (n?=?198) between May 2011 and October 2014 were identified. Overall survival (OS), prostate-specific antigen (PSA) response and progression, and clinical response were compared for second-line chemotherapy vs. ARTA, using one-sided tests from second-line therapy initiation. Multivariate analyses were adjusted for: year, age, metastases, opioid use, Eastern Cooperative Oncology Group performance score, PSA, hemoglobin, alkaline phosphatase, lactate dehydrogenase (LDH), and albumin levels. ResultsPatients receiving second-line chemotherapy vs. ARTA were younger (median: 74 vs. 79 years) and had a poorer prognosis in terms of PSA, LDH, alkaline phosphatase, albumin and hemoglobin levels, opioid use, and Halabi risk score (P upper limit of normal: aHR?=?0.18,P?=?0.014; albumin < lower limit of normal: aHR?=?0.42,P?=?0.020). ConclusionFollowing early progression on first-line ARTA, second-line chemotherapy may be more beneficial in mCRCaP compared with second-line ARTA in patients with a poor prognosis.