A randomized presurgical trial of alternative dosing of exemestane in postmenopausal women with early-stage ER-positive breast cancer.

• DOI: 10.1200/jco.2022.40.16_suppl.519
• Publication Date: 2022-06-06T15:51:47Z
• Authors: Andrea De Censi; Davide Serrano; Sara Gandini; Parijatham S. Thomas; Katherine D. Crew; Nagi B. Kumar; J. Jack Lee; Paolo Veronesi; Aliana Guerrieri-...; Harriet Johansson; Mauro D'Amico; Flavio Guasone; Bjorn-Erik Ertelsen; Gunnar Mellgren; Isabelle Bedrosian; Eileen Dimond; Brandy M. Heckman...; Eva Szabo; Powel Brown; Bernardo Bonanni
• Keywords: Exemestane; Clinical endpoint

519 Background: Successful therapeutic cancer prevention requires definition of the minimal effective dose proposed agent. Aromatase inhibitors substantially decreased breast incidence in high risk postmenopausal women phase III trials but their clinical use and adherence adjuvant setting is limited by adverse events. We conducted a randomized presurgical IIb trial to evaluate two alternative doses exemestane. Methods: multi-center, pre-surgical, double-blind, 3-arm, non-inferiority study with histologically confirmed estrogen receptor (ER)-positive cancer. Patients were receive either exemestane 25 mg/day (QD), or mg/three times/week (TIW), mg once week (QW) for 4-6 weeks before surgery. Blood tissue biomarkers collected at baseline final visit. The primary aim was percent change circulating estradiol relative standard dose. Secondary endpoints Ki-67 PgR expression tissue, blood sex hormones, lipid profile, toxicity menopausal symptoms. For power calculation we assumed difference 6% percentage among arms, using one-sided, two-sample t-test. Assuming 10% drop-out rate, total sample size 180 participants (60 per arm) had 80% detect margin equivalence. significance level main endpoint 0.025 account multiple comparisons 0.05 secondary endpoints. Results: A 230 screened, agreed participate 173 evaluable response. median -98%, -70% QD (n = 56), TIW 57), QW 60), respectively, showing no significant between arms (p 0.9). Similarly, differences observed estrone, estrone sulfate arms. arm showed some modulation all even though less significantly so. Among endpoints, reduced -5% vs -7.5% Ki-67(p 0.124), -9 -17 0.246) respectively. SHBG HDL-cholesterol more favorable profile compared daily Adverse events, measured according CTCAE (v4), symptoms MENQOL similar short treatment time may not be representative. Conclusions: Exemestane retains comparable activity than QD. This both throughout new schedule should further assessed studies on who do tolerate Clinical information: NCT02598557.