The Influence of Prednisone on the Efficacy of Cabazitaxel in Men with Metastatic Castration-Resistant Prostate Cancer.

Background: Cabazitaxel is a second-generation taxane that is approved for use with concomitant low dose daily prednisone in metastatic castration resistant prostate cancer (mCRPC) after docetaxel failure. Since the role of daily corticosteroids in improving cabazitaxel efficacy or ameliorating its safety profile has not been adequately investigated so far, we compared outcomes of patients receiving cabazitaxel with or without daily corticosteroids in a retrospective single-Institution cohort of mCRPC patients. Patients and methods: Medical records of deceased patients with documented mCRPC treated with cabazitaxel following prior docetaxel between January, 2011 and January, 2017 were reviewed at the single participating center. Patients who were receiving daily doses of systemic corticosteroids other than low dose daily prednisone or prednisolone (<= 10 mg a day) were excluded. The primary end point of this analysis was overall survival (OS). Secondary end-points were exposure to cabazitaxel as well as incidence of grade 3-4 adverse events. Univariable and multivariable Cox proportional hazards regression was used to evaluate prednisone use and other variables as potentially prognostic for overall survival. Results: Overall, among 91 patients, 57 patients received cabazitaxel concurrently with low dose prednisone and 34 patients did not receive concurrent prednisone. The median overall survival of the population was 9.8 months (interquartile range, 9 to 14). Patients receiving prednisone had an overall survival of 9 months (interquartile range, 8 to 12) vs.14 months (interquartile range, 9.4 to 16.7) for patients not treated with prednisone. Approximately 45% of patients had a >30% PSA decline at 12 weeks. Prednisone use was not significantly prognostic for overall survival or PSA decline ≥30% rates on regression analyses. Importantly, a >30% PSA decline at 12, but not at 3, 6, 9 weeks, was prognostic for improved survival at multivariate analysis Conclusions: The data presented here support the hypothesis that omitting daily corticosteroids in cabazitaxel-treated patients has no negative impact on either survival or safety profile. In the large prospective trial CABACARE, cabazitaxel-treated patients will be randomized to receive or not receive daily prednisone. The CABACARE (EudraCT n. 2016-003646-81) study is currently ongoing at University Federico II of Naples and at other multiple participating centers in Italy.
Competing Interests: Competing Interests: Carlo Buonerba & Giuseppe Di Lorenzo: Research Support to Institution from Astellas, Sanofi and Quercegen Pharmaceuticals, personal fees from for Sanofi (unrelated to this work) Guru Sonpavde: Grants from Boehringer-Ingelheim, grants from Bayer, grants from Onyx-Amgen, personal fees from Pfizer, personal fees from Genentech, personal fees from Novartis, personal fees from Argos, grants and personal fees from Merck, personal fees from Sanofi, personal fees from Agensys, personal fees from Clinical Care Options, personal fees from Astrazeneca, personal fees from Uptodate, personal fees from Biotheranostics, personal fees from Exelixis, personal fees from Bristol-Myers-Squibb, personal fees from Janssen, personal fees from Amgen, personal fees from Eisai, personal fees from NCCN (National Comprehensive Cancer Network), outside the submitted work.