AstraZeneca and Daiichi Sankyo have reported that experimental breast cancer drug trastuzumab deruxtecan (DS-8201) halted cancer in women who had exhausted other treatment options in a Phase II single-arm DESTINY-Breast01 trial.
The single-arm, open-label, global, multi-centre, two-part DESTINY-Breast01 trial evaluated the safety and efficacy of DS-8201, a HER2-targeting antibody-drug conjugate (ADC).
Independent central review confirmed that the trial’s primary endpoint of objective response rate (ORR) was 60.9% with DS-8201 monotherapy (5.4mg/kg).
The trial’s secondary objectives include duration of response, disease control rate, clinical benefit rate, progression-free survival and overall survival.
AstraZeneca R&D Oncology executive vice-president José Baselga said: “The clinically meaningful and durable responses seen among these patients illustrate the potential of DS-8201 to establish a new standard of care.
“These results are impressive, as women with this advanced stage of breast cancer have already endured multiple prior therapies for HER2 positive metastatic breast cancer.”
AstraZeneca and Daiichi Sankyo enrolled 253 patients at more than 100 sites across North America, Europe and Asia for the DESTINY-Breast01 trial. Enrollment was completed in September last year.
The safety and tolerability profile of the breast cancer drug was consistent with that observed in the Phase I trial.
Daiichi Sankyo and AstraZeneca entered a global collaboration in March this year to jointly develop and commercialise DS-8201 as a potential new medicine in all countries except Japan.
The drug recently received Priority Review from the US Food and Drug Administration (FDA) for the Biologics License Application (BLA) to treat HER2 metastatic breast cancer.
The companies also made a regulatory submission for DS-8201 to Japan’s Ministry of Health, Labour and Welfare (MHLW) for the treatment of HER2 positive metastatic breast cancer.
Last June, Daiichi Sankyo dosed the first patient in a Phase II trial evaluating the efficacy and safety of DS-8201 for the treatment of patients with unresectable and/or metastatic non-squamous HER2-overexpressing or HER2-mutated non-small cell lung cancer (NSCLC).