On August 29, Daiichi Sankyo announced that the U.S. Food and Drug Administration (FDA) has granted Breakthrough Therapy designation to DS-8201, an investigational HER2-targeting antibody-drug conjugate, for the treatment of patients with HER2-positive, locally advanced or metastatic breast cancer who have been treated with trastuzumab (Herceptin) and pertuzumab (Perjeta) and have disease progression after therapy with ado-trastuzumab emtansine (also known as T-DM1 [Kadcyla]).
Currently, there is no FDA-approved therapy for patients with HER2-positive metastatic breast cancer with disease progression following treatment with the other HER2-targeting agents trastuzumab, pertuzumab, and ado-trastuzumab emtansine.
“The Breakthrough Therapy designation for DS-8201 in HER2-positive metastatic breast cancer acknowledges the unmet medical need these patients face when currently approved treatments no longer control their disease,” said Antoine Yver, MD, MSc, Executive Vice President and Global Head, Oncology Research and Development, Daiichi Sankyo. “We remain committed to rapidly progressing the development of DS-8201 and look forward to working closely with the FDA to potentially bring this new treatment option to patients with metastatic breast cancer as quickly as possible.”
The Breakthrough Therapy designation was granted based on the results of the ongoing phase I study assessing the safety, tolerability, and preliminary efficacy of DS-8201. In the phase I study, no dose-limiting toxicities were observed, and the maximum tolerated dose was not reached. Preliminary results of DS-8201 from a subgroup analysis of HER2-expressing metastatic breast cancer pretreated with trastuzumab, pertuzumab, and ado-trastuzumab emtansine were recently presented by Doi et al at the 2017 ASCO Annual Meeting.
DS-8201 is a “smart” chemotherapy comprising a humanized HER2 antibody attached to a novel topoisomerase I inhibitor (DXd) payload by a tetrapeptide linker. It is designed to deliver enhanced cell destruction upon release inside the cell and reduce systemic exposure to the cytotoxic payload, as compared to the way chemotherapy is commonly delivered.
In addition to Breakthrough Therapy designation, the FDA has granted Fast Track designation to DS-8201 for the treatment of HER2-positive unresectable and/or metastatic breast cancer in patients with disease progression after prior treatment with HER2-targeted therapies including ado-trastuzumab emtansine.
The content in this post has not been reviewed by the American Society of Clinical Oncology, Inc. (ASCO®) and does not necessarily reflect the ideas and opinions of ASCO®.