Antitumour Activity and Safety of Enzalutamide in Patients with Metastatic Castration-resistant Prostate Cancer Previously Treated with Abiraterone Acetate Plus Prednisone for ≥24 weeks in Europe.
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Date
2018-07-01ICR Author
Author
de Bono, JS
Chowdhury, S
Feyerabend, S
Elliott, T
Grande, E
Melhem-Bertrandt, A
Baron, B
Hirmand, M
Werbrouck, P
Fizazi, K
Type
Journal Article
Metadata
Show full item recordAbstract
BACKGROUND: Enzalutamide and abiraterone acetate plus prednisone, which target the androgen receptor axis, have expanded the treatment of advanced prostate cancer. Retrospective analyses suggest some cross-resistance between these two drugs when used sequentially, but robust, prospective studies have not yet been reported. OBJECTIVE: To fulfil a regulatory postregistration commitment by evaluating the efficacy and safety of enzalutamide in patients with metastatic castration-resistant prostate cancer (mCRPC) who progressed following abiraterone acetate plus prednisone treatment. DESIGN, SETTING, AND PARTICIPANTS: Multicentre, single-arm, open-label study, enrolled patients with progressing mCRPC after ≥24 wk of abiraterone acetate plus prednisone treatment. All patients maintained castration therapy during the trial. Prior chemotherapy was allowed but not required. INTERVENTION: Patients received enzalutamide 160mg/d orally. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: The primary endpoint was radiographic progression-free survival. Secondary endpoints were overall survival, prostate-specific antigen (PSA) response, and time-to-PSA progression. Safety data were also assessed. Kaplan-Meier methods were used to descriptively analyse time-to-event endpoints. RESULTS AND LIMITATIONS: Overall, 214 patients received enzalutamide treatment, 145 of whom were chemotherapy-naïve. Median radiographic progression-free survival was 8.1 mo (95% confidence interval: 6.1-8.3); median overall survival had not been reached. Unconfirmed PSA response rate was 27% (48 of 181). Median time-to-PSA progression was 5.7 mo (95% confidence interval: 5.6-5.8). The most common treatment-emergent adverse events were fatigue (32%), decreased appetite (25%), asthenia (18%), back pain (17%), and arthralgia (16%). No seizures were reported. CONCLUSIONS: Enzalutamide showed antitumour activity in some patients with mCRPC who had previously progressed following ≥24 wk of abiraterone acetate plus prednisone treatment. PATIENT SUMMARY: Patients with mCRPC who progressed on previous abiraterone acetate plus prednisone treatment, with or without prior chemotherapy, received enzalutamide. Although cross-resistance between the two agents was observed in a majority of patients, some still benefited from enzalutamide treatment.
Collections
Subject
Humans
Disease Progression
Phenylthiohydantoin
Prednisone
Androgen Antagonists
Antineoplastic Combined Chemotherapy Protocols
Treatment Outcome
Drug Resistance, Neoplasm
Aged
Middle Aged
Europe
Male
Prostatic Neoplasms, Castration-Resistant
Abiraterone Acetate
Research team
Prostate Cancer Targeted Therapy Group
Language
eng
Date accepted
2017-07-26
License start date
2018-07
Citation
European urology, 2018, 74 (1), pp. 37 - 45
Publisher
ELSEVIER