Anastrozole single-dose protocol in women with oligo- or anovulatory infertility: results of a randomized phase II dose-response study.
Author(s): Tredway D, Schertz JC, Bock D, Hemsey G, Diamond MP
Affiliation(s): Global Clinical Development Unit, EMD Serono, Inc., Rockland, MA 02370, USA.
Publication date & source: 2011-04, Fertil Steril., 95(5):1725-9.e1-8.
Publication type: Clinical Trial, Phase II; Multicenter Study; Randomized Controlled Trial; Research Support, Non-U.S. Gov't
OBJECTIVE: To compare the effects of anastrozole and clomiphene citrate (CC) on follicular development and ovulation in infertile women with ovulatory dysfunction. DESIGN: Phase II, prospective, randomized, assessor-blind, multicenter, dose-finding, noninferiority study. SETTING: Outpatient. PATIENT(S): Infertile women with ovulatory dysfunction, aged 18-35 years, and body mass index <35 kg/m(2). INTERVENTION(S): Single-dose anastrozole at 5 mg (n = 39), 10 mg (n = 39), 20 mg (n = 39), or 30 mg (n = 38) or a 5-day course of CC at 50 mg/d (n = 39) as starting doses. MAIN OUTCOME MEASURE(S): The primary endpoint was the ovulation rate in the first treatment cycle (cycle 1). Ovulation was defined as a midluteal phase serum P level >/= 10 ng/mL or clinical pregnancy. RESULT(S): In cycle 1 the ovulation rates for a single dose of anastrozole at 5, 10, 20, and 30 mg were 46.2%, 41.0%, 23.1%, and 28.9%, respectively, whereas that for CC at 50 mg/d was 61.5%. Among women with fewer than six menses per year, the cumulative ovulation rates over three cycles were comparable in the anastrozole 5 mg (52.4%) and CC 50 mg/d (42.3%) groups. CONCLUSION(S): In terms of ovulation rates in cycle 1, single-dose anastrozole at 5, 10, 20, and 30 mg was not as effective as CC at 50 mg/d for 5 days (noninferiority was not shown). Copyright (c) 2011 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.