FDA Grants Priority Review to Trastuzumab Deruxtecan for HER2+ Metastatic Breast Cancer

October 17, 2019

The agency is set to make a decision on the investigational antibody drug conjugate by the first quarter of 2020.

The FDA granted a priority review to the biologics license application for trastuzumab deruxtecan (DS-8201) for the treatment of patients with HER2-positive metastatic breast cancer, according to AstraZeneca, the agent’s manufacturer.

The Prescription Drug User Fee Act (PDUFA) date is set for the first quarter of fiscal year 2020.

“Trastuzumab deruxtecan has the potential to transform the treatment landscape for patients with HER2-positive metastatic breast cancer who have limited treatment options,” José Baselga, MD, PhD, executive vice president, research and development, oncology, AstraZeneca, said in a press release. “The priority review draws on the strength and consistency of results seen in phase I and phase II trials and is an important step on the journey to deliver this potential new medicine to patients.”

The biologics license application was based on findings from the phase I safety results published earlier this year in Lancet Oncology, as well as data from the ongoing, pivotal phase II DESTINY-Breast01 trial.

In the open-label, global multicenter, 2-part trial, researchers evaluated the efficacy and safety of trastuzumab deruxtecan in 253 patients with HER-positive, unresectable and/or metastatic breast cancer who were previously treated with trastuzumab emtansine.

Objective response rate (ORR), determined by independent central review, served as the primary endpoint. Secondary endpoints included duration of response (DOR), disease control rate (DCR), clinical benefit rate, as well as progression-free (PFS) and overall survival (OS).

Patients achieved an ORR of 59.5% (95% CI, 49.7-68.7). Median duration of response was 20.7 months (range, 0.0-21.8) with a DCR of 93.7% (95% CI, 87.4-97.4). Moreover, median PFS was 22.1 months (range, 0.8-27.9). Median OS was not been reached yet.

Further results from the DESTINY-Breast01 trial will be presented in December at the San Antonio Breast Cancer Symposium, according to the press release.

References:

Shitara K, Iwata H, Takahashi S, et al. Trastuzumab deruxtecan (DS-8201a) in patients with advanced HER2-positive gastric cancer: a dose-expansion, phase 1 study. Lancet Oncol. 2019 Jun;20(6):827-836. doi: 10.1016/S1470-2045(19)30088-9.