Investig Clin Urol.  2020 Jan;61(1):19-27. 10.4111/icu.2020.61.1.19.

Enzalutamide in chemotherapy-naive patients with metastatic castration-resistant prostate cancer: A retrospective Korean multicenter study in a real-world setting

• Jung SI
• Kim MS
• Jeong CW
• Kwak C
• Hong SK
• Kang SH
• Joung JY
• Lee SH
• Yun SJ
• Kim TH
• Park SW
• Jeon SS
• Kang M
• Lee JY
• Chung BH
• Hong JH
• Ahn H
• Kim CS
• Kwon DD

• KMID: 2466788
• DOI: http://doi.org/10.4111/icu.2020.61.1.19

Abstract

PURPOSE
This study aimed to evaluate the clinical efficacy of enzalutamide in chemotherapy-naïve metastatic castration-resistant prostate cancer (mCRPC) patients using real-world data from Korean patients.
MATERIALS AND METHODS
We retrospectively reviewed the medical records of 199 chemotherapy-naïve patients with mCRPC at 13 tertiary centers in Korea between 2014 and 2017. All patients received enzalutamide daily and 89 patients received concurrent androgen deprivation therapy (ADT).
RESULTS
The median age of the patients was 74 years. Initial results showed that 81.5% of the patients had Gleason score ≥8 and 33.3% of the patients had European Cooperative Oncology Group Performance Status 0. The overall mortality rate was 12%. The median OS was not archieved and 76.7% of patients were alive at 30 months. Median time until PSA progression was 6 months. The overall survival rate at 2 years was significantly higher (84.6% vs. 71.7%, p=0.015) and the duration of PSA progression-free survival was significantly longer (8.0 vs. 4.6 months, p=0.008) in patients receiving concurrent ADT than in those receiving enzalutamide alone. The incidence of adverse events of grade 3 or higher was 1.7%. Multivariate Cox proportional hazard analysis indicated that ADT administered concurrently with enzalutamide significantly improved the overall survival (hazard ratio, 0.346; 95% confidence interval, 0.125-0.958).
CONCLUSIONS
Enzalutamide is effective and safe for chemotherapy-naïve patients with mCRPC. Furthermore, the overall survival was significantly higher in patients receiving enzalutamide and concurrent ADT than in patients receiving enzalutamide alone.

Keyword

Androgen antagonists; Neoplasm metastasis; Prostate neoplasms; Treatment outcome

MeSH Terms

Androgen Antagonists
Disease-Free Survival
Humans
Incidence
Korea
Medical Records
Mortality
Neoplasm Grading
Neoplasm Metastasis
Prostate*
Prostatic Neoplasms*
Retrospective Studies*
Survival Rate
Treatment Outcome
Androgen Antagonists

Figure

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  Fig. 1 Kaplan–Meier survival curves for (A) overall survival and (B) radiographic progression-free survival in PREVAIL study [6], in PREVAIL Korean post hoc analysis [10], and in this study.

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  Fig. 2 According to concurrent androgen deprivation therapy (ADT), Kaplan–Meier survival estimates for (A) overall survival and (B) time to prostate-specific antigen (PSA) progression-free survival, and (C) radiographic progression-free survival.

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  Fig. 3 Waterfall plot for prostate-specific antigen (PSA) response according to concurrent androgen deprivation therapy (ADT).

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