title: A randomized, double-blind, controlled study of exemestane versus anastrozole for the first-line treatment of postmenopausal Japanese women with hormone-receptor-positive advanced breast cancer.
abstract: The aromatase inhibitors exemestane and anastrozole are approved in Japan for first-line treatment of postmenopausal patients with advanced, hormone-receptor-positive breast cancer. This phase 3, randomized, double-blind study directly compared time to progression (TTP) for exemestane and anastrozole therapy in this patient population. Eligible patients were randomized to receive exemestane 25 mg or anastrozole 1 mg, each once daily. The primary endpoint was TTP based on assessment by an expert radiologic images review committee (ERIRC). Secondary endpoints included investigator-assessed TTP, time to treatment failure, overall survival, objective response rate, clinical benefit rate, and safety. A total 298 patients were randomized to receive exemestane (n = 149; mean age 63.4 years) or anastrozole (n = 149; mean age 64.0 years). Median ERIRC-assessed TTP was 13.8 and 11.1 months (hazard ratio = 1.007; 95 % confidence interval [CI]: 0.771, 1.317) and median investigator-assessed TTP was 13.8 and 13.7 months (hazard ratio = 1.059; 95 % CI: 0.816, 1.374) in the exemestane and anastrozole arms, respectively. Median overall survival was 60.1 months in the anastrozole arm and was not reached in the exemestane arm at data cutoff. The objective response rate was 43.9 % (95 % CI: 35.3, 52.8) and 39.1 % (95 % CI: 30.6, 48.1) in the exemestane and anastrozole arms, respectively. Treatment-related adverse events grade ≥3 occurred in 9.4 and 6.0 % of patients, and treatment-related serious adverse events occurred in 4.0 and 3.4 % of patients in the exemestane and anastrozole arms, respectively. In this study, the efficacy and safety profiles of exemestane were similar to those of anastrozole in Japanese patients with advanced, hormone-receptor-positive breast cancer; however, TTP non-inferiority of exemestane versus anastrozole was not confirmed.
authors.affiliation: Aichi Cancer Center Hospital, Aichi, Japan.
authors.forename: Hiroji
authors.initials: H
authors.lastname: Iwata
authors.forename: Norikazu
authors.initials: N
authors.lastname: Masuda
authors.forename: Shinji
authors.initials: S
authors.lastname: Ohno
authors.forename: Yoshiaki
authors.initials: Y
authors.lastname: Rai
authors.forename: Yasuyuki
authors.initials: Y
authors.lastname: Sato
authors.forename: Shozo
authors.initials: S
authors.lastname: Ohsumi
authors.forename: Satoshi
authors.initials: S
authors.lastname: Hashigaki
authors.forename: Yoshinori
authors.initials: Y
authors.lastname: Nishizawa
authors.forename: Masahiro
authors.initials: M
authors.lastname: Hiraoka
authors.forename: Tadaoki
authors.initials: T
authors.lastname: Morimoto
authors.forename: Hironobu
authors.initials: H
authors.lastname: Sasano
authors.forename: Toshiaki
authors.initials: T
authors.lastname: Saeki
authors.forename: Shinzaburo
authors.initials: S
authors.lastname: Noguchi
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000077384:Anastrozole; D000730:Androstadienes / Q000009:adverse effects / Q000627:therapeutic use*; D018931:Antineoplastic Agents, Hormonal / Q000009:adverse effects / Q000627:therapeutic use*; D047072:Aromatase Inhibitors / Q000009:adverse effects / Q000627:therapeutic use*; D015415:Biomarkers / Q000378:metabolism; D001842:Bone and Bones / Q000378:metabolism; D001943:Breast Neoplasms / Q000188:drug therapy* / Q000378:metabolism / Q000401:mortality / Q000473:pathology; D005260:Female; D006801:Humans; D007564:Japan; D008055:Lipids / Q000097:blood; D008875:Middle Aged; D060787:Neoplasm Grading; D009570:Nitriles / Q000009:adverse effects / Q000627:therapeutic use*; D017698:Postmenopause; D016896:Treatment Outcome; D014230:Triazoles / Q000009:adverse effects / Q000627:therapeutic use*
chemical_list: D000730:Androstadienes; D018931:Antineoplastic Agents, Hormonal; D047072:Aromatase Inhibitors; D015415:Biomarkers; D008055:Lipids; D009570:Nitriles; D014230:Triazoles; D000077384:Anastrozole; C056516:exemestane