Open AccessInitial dose reduction of enzalutamide does not decrease the incidence of adverse events in castration-resistant prostate cancer
Author(s) -
Shunsuke Tsuzuki,
Shotaro Nakanishi,
Mitsuyoshi Tamaki,
Takeshi Oshiro,
Jun Miki,
Hiroki Yamada,
Takeshi Shimomura,
Takahiro Kimura,
Nozomu Furuta,
Sei–Ichi Saitoh,
Shin Egawa
Publication year - 2021
Publication title -
plos one
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.99
H-Index - 332
ISSN - 1932-6203
DOI - 10.1371/journal.pone.0258160
Subject(s) - enzalutamide , medicine , prostate cancer , incidence (geometry) , adverse effect , urology , propensity score matching , cohort , oncology , cancer , androgen receptor , physics , optics
Background There was no clear evidence whether the initial dose of enzalutamide affects the incidence of adverse events (AEs), and oncological outcome in patients with castration-resistant prostate cancer (CRPC). Methods The clinical charts of 233 patients with CRPC treated with enzalutamide were reviewed retrospectively. After 1:3 propensity score matching (PSM), 124 patients were divided into a reduced dose group and a standard dose group, and the prostate specific antigen (PSA) response and the incidence of AEs were compared. Results 190 patients with CRPC initiated with standard dose enzalutamide were younger and better performance status compared with 43 patients beginning with reduced dose. After PSM, the baseline characteristics were not different between the standard and the reduced dose group. In the PSM cohort, the PSA response rate was significantly lower in the reduced dose group than in the standard dose group (-66.3% and -87.4%, p = 0.02). The incidence rates of AEs were not statistically different between the groups (22.6% and 34.4%, respectively, p = 0.24). Conclusion Initiating treatment with a reduced dose of enzalutamide did not significantly decrease the incidence rate of AEs, and it showed poorer PSA response rate. There is no clear rationale for treating with a reduced initial dose of enzalutamide to reduce the incidence of AEs.