Cardiff University | Prifysgol Caerdydd ORCA
Online Research @ Cardiff 
WelshClear Cookie - decide language by browser settings

Dose-dependent change in biomarkers during neoadjuvant endocrine therapy with fulvestrant: results from NEWEST, a randomized Phase II study

Kuter, Irene, Gee, Julia Margaret Wendy, Hegg, Roberto, Singer, Christian F., Badwe, Rajendra A., Lowe, Elizabeth S., Emeribe, Ugochi A., Anderson, Elizabeth, Sapunar, Francisco, Finlay, Pauline, Nicholson, Robert Ian, Bines, José and Harbeck, Nadia 2012. Dose-dependent change in biomarkers during neoadjuvant endocrine therapy with fulvestrant: results from NEWEST, a randomized Phase II study. Breast Cancer Research and Treatment 133 (1) , pp. 237-246. 10.1007/s10549-011-1947-7

Full text not available from this repository.

Abstract

NEWEST (Neoadjuvant Endocrine Therapy for Women with Estrogen-Sensitive Tumors) is the first study to compare biological and clinical activity of fulvestrant 500 versus 250 mg in the neoadjuvant breast cancer setting. We hypothesized that fulvestrant 500 mg may be superior to 250 mg in blocking estrogen receptor (ER) signaling and growth. A multicenter, randomized, open-label, Phase II study was performed to compare fulvestrant 500 mg (500 mg/month plus 500 mg on day 14 of month 1) versus fulvestrant 250 mg/month for 16 weeks prior to surgery in postmenopausal women with ER+ locally advanced breast cancer. Core biopsies at baseline, week 4, and surgery were assessed for biomarker changes. Primary endpoint: change in Ki67 labeling index (LI) from baseline to week 4 determined by automated computer imaging system (ACIS). Secondary endpoints: ER protein expression and function; progesterone receptor (PgR) expression; tumor response; tolerability. ER and PgR were examined retrospectively using the H score method. A total of 211 patients were randomized (fulvestrant 500 mg: n = 109; 250 mg: n = 102). At week 4, fulvestrant 500 mg resulted in greater reduction of Ki67 LI and ER expression versus 250 mg (−78.8 vs. −47.4% [p < 0.0001] and −25.0 vs. −13.5% [p = 0.0002], respectively [ACIS]); PgR suppression was not significantly different (−22.7 vs. −17.6; p = 0.5677). However, H score detected even greater suppression of ER (−50.3 vs. −13.7%; p < 0.0001) and greater PgR suppression (−80.5 vs. −46.3%; p = 0.0018) for fulvestrant 500 versus 250 mg. At week 16, tumor response rates were 22.9 and 20.6% for fulvestrant 500 and 250 mg, respectively, with considerable decline in all markers by both ACIS and H score. No detrimental effects on endometrial thickness or bone markers and no new safety concerns were identified. This provides the first evidence of greater biological activity for fulvestrant 500 versus 250 mg in depleting ER expression, function, and growth.

Item Type: Article
Date Type: Publication
Status: Published
Schools: Pharmacy
Subjects: R Medicine > RS Pharmacy and materia medica
Uncontrolled Keywords: Estrogen receptor-positive breast cancer – Fulvestrant 500 mg – Faslodex® – Neoadjuvant – Biomarkers
Publisher: Springer
ISSN: 0167-6806
Last Modified: 04 Jun 2017 03:08
URI: http://orca-mwe.cf.ac.uk/id/eprint/17256

Citation Data

Cited 16 times in Google Scholar. View in Google Scholar

Cited 57 times in Scopus. View in Scopus. Powered By Scopus® Data

Actions (repository staff only)

Edit Item Edit Item