Daiichi Sankyo Company, Limited announced that safety and preliminary efficacy phase 1 data evaluating DS-8201a, a novel HER2-targeting antibody drug conjugate, will be presented during a late-breaking poster discussion session during the European Society for Medical Oncology (ESMO) 2016 Congress from October 7 -11 in Copenhagen, Denmark.

“We are looking forward to presenting these results for DS-8201a to the scientific community at ESMO,” said Antoine Yver, MD, MSc, executive vice president and global head, oncology research and development, Daiichi Sankyo. “Additionally, for the first time we will be showcasing our innovative in-house antibody drug conjugate technology that was used to develop DS-8201a.”

LBA17: Single Agent Activity of DS-8201a, a HER2-Targeting Antibody-Drug Conjugate, in Breast Cancer Patients Previously Treated with T-DM1: Phase 1 Dose Escalation.

Results from part 1 (dose escalation) of a two-part phase 1 study of DS-8201a by Kenji Tamura, MD, PhD, Chairman, Department of Breast and Medical Oncology, National Cancer Center Hospital, Tokyo will be presented on Sunday, October 9 at 4:30 pm CEST. The primary objective of the dose escalation part of the study was to examine the safety and tolerability of DS-8201a along with determining the maximum tolerated dose. Secondary objectives include evaluating the pharmacokinetics and efficacy of DS-8201a. Additional sub-group analyses of preliminary efficacy of DS-8201a in advanced or metastatic breast cancer patients previously treated with ado-trastuzumab emtansine (T-DM1) will be presented.

DS-8201a is an investigational antibody drug conjugate comprised of a humanized anti-HER2 antibody attached by a peptide linker to a novel topoisomerase I inhibitor, utilizing Daiichi Sankyo’s proprietary payload and linker-payload technology. It is currently in phase 1 clinical development for HER2 expressing advanced or metastatic breast cancer or gastric cancer and other HER2 expressing solid cancers.

The second part (dose expansion) of the phase 1 clinical trial evaluating the safety and efficacy of DS-8201a is currently underway, and will enroll patients in the United States and Japan into one of four treatment cohorts: patients with HER2+ breast cancer previously treated with T-DM1; patients with HER2+ gastric or gastroesphageal junction adenocarcinoma previously treated with trastuzumab; patients with HER2-low expressing breast cancer; and, patients with other solid cancers that express HER2.