Daiichi Sankyo expands DS-1062 study to include patients with triple negative breast cancer

Daiichi Sankyo Company announced the first patient with triple negative breast cancer (TNBC) has been dosed in the ongoing phase 1 study assessing DS-1062, a TROP2 directed DXd antibody drug conjugate (ADC).

Patients with TNBC, an aggressive subtype of breast cancer, have limited treatment options beyond standard chemotherapy. High TROP2 expression has been reported in up to 80 percent of patients with TNBC.

“Following the promising preliminary results reported with DS-1062 in patients with non-small cell lung cancer, we have expanded the study to include patients with triple negative breast cancer,” said Gilles Gallant, BPharm, PhD, FOPQ, Senior Vice President, Global Head, Oncology Development, Oncology R&D, Daiichi Sankyo. “We continue to follow the science to determine whether DS-1062, designed with our proprietary DXd ADC technology, could serve as a new TROP2 directed therapy option for patients with TNBC and other cancers.”

The first-in-human, open-label, two-part, multi-center phase 1 study is designed to evaluate the safety, tolerability and preliminary efficacy of DS-1062 in patients with TROP2 unselected advanced solid tumors, which are refractory to or relapsed from standard treatment or for whom no standard treatment is available.

The first part of the study (dose escalation) assessed the safety and tolerability of increasing doses of DS-1062 to determine the maximum tolerated dose (MTD) and/or recommended dose for expansion (RDE) in patients with unresectable advanced NSCLC. The second part of the study (dose expansion) is further assessing the safety and tolerability of DS-1062 at selected dose levels for NSCLC. A cohort of patients with unresectable/advanced or metastatic TNBC has been added.

The study is currently enrolling approximately 180 patients in the U.S. and Japan with advanced unresectable NSCLC to receive DS-1062 at doses of 4, 6, and 8 mg/kg, and approximately 40 patients with advanced/unresectable or metastatic TNBC will receive DS-1062 at the 8 mg/kg dose. Patient enrollment in the dose expansion part of the study may be further expanded to include additional tumor types.

Safety endpoints include dose limiting toxicities and serious adverse events. Efficacy endpoints include objective response rate, duration of response, disease control rate, time to response, progression-free survival and overall survival. Pharmacokinetic, biomarker and immunogenicity endpoints also will be evaluated.

Updated data from this study in patients with heavily pre-treated advanced non-small cell lung cancer (NSCLC) were recently presented at the 2020 American Society of Clinical Oncology (ASCO) Virtual Scientific Program (#ASCO20).