title: Dose Reduction versus Dose-interval Prolongation in Eribulin Mesilate Monotherapy in Patients with Metastatic Breast Cancer: A Retrospective Comparative Study.
abstract: It is often necessary to modify the dose or schedule of eribulin mesilate (Eri) because of adverse events. Therefore, we retrospectively investigated the optimal approach for Eri dose adjustment and/or dosage interval adjustment. Patients who received Eri at the institutions affiliated with the Division of Oncology of the Aichi Prefectural Society of Hospital Pharmacists between July 2011 and November 2013 were enrolled in this study. We compared the group that underwent dose reduction without changes to their dosage interval (dose reduction group) with the group that had a change in their dosage interval (dose-interval prolongation group). The primary end-point was time to treatment failure (TTF), and the secondary end-points were overall survival (OS), overall response rate (ORR), clinical benefit rate (CBR), and adverse events. The TTF and OS of the dose reduction group were approximately two times longer than those of the dose-interval prolongation group. In addition, the dose reduction group had significantly improved ORR and CBR, which together indicate an antitumor effect (p=0.013 and 0.002, respectively). Although peripheral neuropathy occurred significantly more frequently in the patients in the dose reduction group (p=0.026), it was grade 1 and controllable in most of the cases. There were no differences in the occurrence of other adverse effects between the two groups. Therefore, we suggest that dose reduction with maintenance of the dosage interval is the preferred treatment approach in cases where Eri dose or schedule modification is necessary.
authors.affiliation: Department of Pharmacy, Mikawa Breast Cancer Clinic.
authors.forename: Toshinori
authors.initials: T
authors.lastname: Sasaki
authors.forename: Yumiko
authors.initials: Y
authors.lastname: Oshima
authors.forename: Etsuko
authors.initials: E
authors.lastname: Mishima
authors.forename: Akiko
authors.initials: A
authors.lastname: Ban
authors.forename: Kenji
authors.initials: K
authors.lastname: Katsuragawa
authors.forename: Hidetsugu
authors.initials: H
authors.lastname: Nagamatsu
authors.forename: Yuki
authors.initials: Y
authors.lastname: Yoshioka
authors.forename: Ikuto
authors.initials: I
authors.lastname: Tsukiyama
authors.forename: Tatsuya
authors.initials: T
authors.lastname: Hisada
authors.forename: Yukari
authors.initials: Y
authors.lastname: Itakura
authors.forename: Mitsuhiro
authors.initials: M
authors.lastname: Mizutani
mesh_terms: D000328:Adult; D000368:Aged; D001943:Breast Neoplasms / Q000188:drug therapy* / Q000401:mortality; D004334:Drug Administration Schedule; D023381:Endpoint Determination; D005260:Female; D005663:Furans / Q000008:administration & dosage* / Q000009:adverse effects*; D006801:Humans; D007659:Ketones / Q000008:administration & dosage* / Q000009:adverse effects*; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local; D010523:Peripheral Nervous System Diseases / Q000139:chemically induced / Q000453:epidemiology; D012189:Retrospective Studies; D015996:Survival Rate; D017211:Treatment Failure; D016896:Treatment Outcome; D000095662:Polyether Polyketides
chemical_list: D005663:Furans; D007659:Ketones; C490954:eribulin; D000095662:Polyether Polyketides