LBA4 - Sacituzumab govitecan (SG) vs treatment of physician’s choice (TPC) in Asian patients with hormone receptor-positive and human epidermal growth factor receptor 2-negative (HR+/HER2–) metastatic breast cancer (mBC): Results from the phase III EVER-002 study

Background

Based on results from the global TROPiCS-02 study that enrolled predominantly non-Asian pts, SG has been approved in the US and Europe for pts with pretreated HR+/HER2– mBC. We report first results from the open-label, randomized, multicenter phase 3 EVER-132-002 trial, a pivotal study that assessed SG in Asian pts with endocrine-resistant, chemotherapy (chemo)-treated HR+/HER2– mBC.

Methods

Adults from China, Korea, and Taiwan with HR+/HER2– mBC and 2-4 prior lines of systemic chemo (LOT) were randomized 1:1 to SG (10 mg/kg IV on days 1 and 8; 21-day cycle) or TPC. Pts were stratified based on number of prior LOT, visceral metastasis, and prior treatment with CDK4/6 inhibitors. The primary end point was progression-free survival (PFS) per blinded independent central review (BICR; RECIST v1.1). Secondary end points included overall survival (OS), objective response rate (ORR), clinical benefit rate (CBR) per BICR, and safety.

Results

Pts were randomized to SG (n = 166) or TPC (n = 165); median age was 52 y, 56% and 44% received 2 and 3-4 prior LOT for metastatic disease, respectively. At median follow-up of 13.4 mo, statistically significant improvement of PFS per BICR (33% reduction in the risk of progression or death) and clinically meaningful OS benefit (36% reduction in the risk of death) with SG vs TPC was observed (Table). Additional end points and a summary of treatment-emergent adverse events (TEAEs) are shown in the table. The most common grade ≥ 3 TEAE was neutropenia (69% for SG vs 62% for TPC). Table: LBA4

^aEribulin, capecitabine, gemcitabine, or vinorelbine.

Conclusions

EVER-132-002 confirmed efficacy benefit of SG in Asian pts. The safety profile of SG was generally consistent with prior global studies. The results from this pivotal study support the use of SG as a new treatment option for Asian pts with endocrine-resistant, chemo-treated HR+/HER2– mBC.

Clinical trial identification

NCT04639986.

Editorial acknowledgement

Medical writing assistance was provided by Christiane Dresch, PhD of Parexel.

Legal entity responsible for the study

Gilead Sciences, Inc.

Funding

Gilead Sciences, Inc.

Disclosure

B. Xu: Financial Interests, Personal, Advisory Board: Novartis, AstraZeneca; Financial Interests, Personal, Invited Speaker: Pfizer, Roche; Financial Interests, Institutional, Research Grant: Henrui. S. Wang: Financial Interests, Personal, Invited Speaker: Pfizer, Roche, AstraZeneca, Norvats; Financial Interests, Personal and Institutional, Local PI: Pfizer, AstraZeneca, Roche; Financial Interests, Personal and Institutional, Research Grant: Pfizer. J. Sohn: Financial Interests, Personal, Stocks/Shares, Immediate Family Member: Daiichi Sankyo; Financial Interests, Institutional, Research Grant: MSD, Roche, Novartis, AstraZeneca, Lilly, Pfizer, GSK, Daiichi Sankyo, Sanofi, Boehringer Ingelheim, Seagen. S. Im: Financial Interests, Personal, Advisory Board, no payment: AstraZeneca, Novartis, Eisai, Roche, Hanmi, Pfizer, Lilly, MSD, GSK, Daiichi Sankyo; Financial Interests, Institutional, Advisory Board: Bertis; Financial Interests, Personal, Advisory Board: Idience; Financial Interests, Institutional, Research Grant: AstraZeneca, Pfizer, Roche, Eisai, Dae Woong; Financial Interests, Institutional, Local PI, Clinical Trial Budget: AstraZeneca, Hanmi, Novartis, Roche, Pfizer, Daiichi Sankyo, MSD, Lilly; Financial Interests, Institutional, Coordinating PI, Clinical Trial Budget: Eisai; Financial Interests, Institutional, Research Grant, Clinical Trial Budget: Boryung Pharm. D. Jiang, K.M. Komatsubara: Financial Interests, Personal, Full or part-time Employment: Gilead Sciences Inc.; Financial Interests, Personal, Stocks/Shares: Gilead Sciences Inc. T. Valdez: Financial Interests, Institutional, Stocks/Shares: Gilead Sciences. Y. Zhang: Financial Interests, Personal, Full or part-time Employment, I am a full time employee at Gilead Sciences, Inc. since 01Aug2022.: Gilead Sciences, Inc.; Financial Interests, Personal, Full or part-time Employment, I was a full time employee at Amgen from 28Oct2019 to 29Jul2022.: Amgen; Financial Interests, Personal, Stocks/Shares, I own stock of Gilead Sciences, Inc.: Gilead Sciences, Inc. All other authors have declared no conflicts of interest.