ImportanceSuccessful therapeutic cancer prevention requires definition of the minimal effective dose. Aromatase inhibitors decrease breast cancer incidence in high-risk women, but use in prevention and compliance in adjuvant settings are hampered by adverse events.ObjectiveTo compare the noninferiority percentage change of estradiol in postmenopausal women with estrogen receptor–positive breast cancer given exemestane, 25 mg, 3 times weekly or once weekly vs a standard daily dose with a noninferiority margin of −6%.Design, Setting, and ParticipantsThis multicenter, presurgical, double-blind phase 2b randomized clinical trial evaluated 2 alternative dosing schedules of exemestane. Postmenopausal women with estrogen receptor–positive breast cancer who were candidates for breast surgery were screened from February 1, 2017, to August 31, 2019. Blood samples were collected at baseline and final visit; tissue biomarker changes were assessed from diagnostic biopsy and surgical specimen. Biomarkers were measured in different laboratories between April 2020 and December 2021.InterventionsExemestane, 25 mg, once daily, 3 times weekly, or once weekly for 4 to 6 weeks before surgery.Main Outcomes and MeasuresSerum estradiol concentrations were measured by solid-phase extraction followed by liquid chromatography–tandem mass spectrometry detection. Toxic effects were evaluated using the National Cancer Institute terminology criteria, and Ki-67 was assessed by immunohistochemistry.ResultsA total of 180 women were randomized into 1 of the 3 arms; median (IQR) age was 66 (60-71) years, 63 (60-69) years, and 65 (61-70) years in the once-daily, 3-times-weekly, and once-weekly arms, respectively. In the intention-to-treat population (n = 171), the least square mean percentage change of serum estradiol was −89%, −85%, and −60% for exemestane once daily (n = 55), 3 times weekly (n = 56), and once weekly (n = 60), respectively. The difference in estradiol percentage change between the once-daily and 3-times-weekly arms was −3.6% (P for noninferiority = .37), whereas in compliant participants (n = 153), it was 2.0% (97.5% lower confidence limit, −5.6%; P for noninferiority = .02). Among secondary end points, Ki-67 and progesterone receptor were reduced in all arms, with median absolute percentage changes of −7.5%, −5.0%, and −4.0% for Ki-67 in the once-daily, 3-times-weekly, and once-weekly arms, respectively (once daily vs 3 times weekly, P = .31; once daily vs once weekly, P = .06), and −17.0%, −9.0%, and −7.0% for progesterone receptor, respectively. Sex hormone–binding globulin and high-density lipoprotein cholesterol had a better profile among participants in the 3-times-weekly arm compared with once-daily arm. Adverse events were similar in all arms.Conclusions and RelevanceIn this randomized clinical trial, exemestane, 25 mg, given 3 times weekly in compliant patients was noninferior to the once-daily dosage in decreasing serum estradiol. This new schedule should be further studied in prevention studies and in women who do not tolerate the daily dose in the adjuvant setting.Trial RegistrationClinicalTrials.gov Identifier: NCT02598557; EudraCT: 2015-005063-16
Background: The aromatase inhibitor exemestane (EXE) has shown to lower cancer incidence in high-risk postmenopausal women. However, undesirable symptoms and side effects (i.e., bone density loss, musculoskeletal ache, climacteric syndrome) may compromise patient motivation and adherence to a long-term preventive treatment. A less frequent drug schedule, compared to the standard regimen, may be more acceptable to healthy at-risk women. We hypothesized that comparison of two alternative less frequent dose regimens with the standard daily dose regimen will show that it is possible to decrease undesirable symptoms of EXE while still effectively reducing serum estradiol. Trial Design: We are conducting a multi-center, pre-surgical, double-blind, non-inferiority phase IIb study in which 180 postmenopausal women will be randomized to receive either EXE 25 mg/day or 25 mg/three times a week or 25 mg/week for 4 to 6 weeks prior to surgery. Surgery will occur on day 29, 36 or 43 after treatment initiation. Eligible subjects are postmenopausal women with histologically-confirmed ER-positive (ER >10%) primary breast cancer candidates for surgery. Participants with T0-2, N0-1, Mx or with larger tumors who refuse neo-adjuvant therapy before surgery are eligible. Subjects are stratified according to participating site and body mass index (<25 kg/m2 versus >25 kg/m2). The primary objective is to assess if the reduction in estradiol with EXE 25 mg/three times a week and EXE 25 mg/week is comparable with the standard dose of 25 mg/day of EXE. Methods: Blood will be collected at baseline and at the end of treatment. Tissue samples will be collected from the diagnostic biopsy and at the time of surgery. The primary endpoint is the percentage change of serum estradiol concentration between baseline and surgery in the three arms in a CLIA certified laboratory. Given the expected reduction of at least 80% change with EXE at 25 mg daily considered as reference group (control arm) against 25 mg/three times a week or 25 mg weekly, for the power calculation we assume a non-inferiority difference of 6% in percentage changes of circulating estradiol after treatment from baseline, using a one-sided, two-sample t-test. Secondary outcome measures are the incidence of toxicity and menopausal symptoms according to the CTCAE (v4) and by the self-administered MENQoL; the effect of the three regimens on sex hormones (estrone, estrone sulphate, SHBG, testosterone, DHEAS and FSH) and the effect on circulating estradiol levels using an ultrasensitive method given that the serum levels in postmenopausal women under EXE may be very low. Drug and metabolites levels will be measured in blood, cancer tissue and non-cancer tissue. Evaluation of serum insulin, glucose (homeostatic model assessment index), and lipid profile (total cholesterol, high-density lipoprotein cholesterol and triglycerides), leptin and adiponectin will be performed before and after treatment. Additionally, we will measure breast estradiol concentration in cancer and non-cancer tissue and compare changes in ER, PgR, and proliferation in cancer and non-cancer tissue samples obtained at time of biopsy and definitive surgery. Finally, we will also analyze the role of the polymorphic UGT2B17 gene (involved in EXE and 17-dihydroexemestane metabolism) as well as tissue proteomics. Preliminary results: Enrollment started in February 2017 and as of July 3, 2019, a total of 170/180 participants have been randomized (94% of the expected sample size). Preliminary data will be presented at the conference. IND Sponsor: NCI/DCP NCI contract: HHSN26120120034I Citation Format: Aliana Guerrieri-Gonzaga, Parjhitham Thomas, Andrea DeCensi, Katherine D Crew, Nagi Kumar, Sara Gandini, Lana Vornik, Brandy Heckman-Stoddard, Eva Szabo, Eileen Dimond, Jack Lee, Diane Liu, Matteo Lazzeroni, Sara Cagnacci, Davide Serrano, Mauro D'Amico, Flavio Guasone, Tania Buttiron Webber, Powel Brown, Bernardo Bonanni. Alternative dosing of exemestane before surgery in postmenopausal patients with stage 0-II estrogen receptor positive breast cancer: Design and methodology [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr OT1-04-03.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.