Based on DESTINY-Breast04 results which showed AstraZeneca and Daiichi Sankyo’s Enhertu is the first HER2-directed therapy to demonstrate a survival benefit in this population
Application being evaluated under FDA Real-Time Oncology Review and Project Orbis
AstraZeneca and Daiichi Sankyo have received notification of acceptance of the supplemental Biologics License Application (sBLA) of Enhertu (trastuzumab deruxtecan) for the treatment of adult patients in the US with unresectable or metastatic HER2-low (immunohistochemistry [IHC] 1+ or IHC 2+/in-situ hybridisation [ISH]-negative) breast cancer who have received a prior therapy in the metastatic setting. The application has been granted Priority Review.
The Food and Drug Administration (FDA) grants Priority Review to applications for medicines that, if approved, would offer significant improvements over available options by demonstrating safety or efficacy improvements, preventing serious conditions or enhancing patient compliance. The Prescription Drug User Fee Act date, the FDA action date for their regulatory decision, is during the fourth quarter of 2022.
The sBLA is being reviewed under the Real-Time Oncology Review (RTOR) programme and Project Orbis, two initiatives of the FDA which are designed to bring safe and effective cancer treatments to patients as early as possible. RTOR allows the FDA to review components of an application before submission of the complete application. Project Orbis provides a framework for concurrent submission and review of oncology medicines among participating international partners.
Susan Galbraith, Executive Vice President, Oncology R&D, AstraZeneca, said: “The data from DESTINY-Breast04 represent the first time a HER2-targeted therapy has shown a survival benefit in patients with HER2-low metastatic breast cancer. For more than two decades, only patients with HER2-positive breast cancer have been able to benefit from HER2-targeted therapies. If approved, Enhertu will redefine how we classify and treat metastatic breast cancer, enabling patients whose tumours have lower levels of HER2 expression the opportunity to benefit from a HER2-directed therapy.”
Ken Takeshita, Global Head, R&D, Daiichi Sankyo, said: “The results seen in the DESTINY-Breast04 trial represent a significant advance and reinforce the potential for Enhertu to become a new standard of care for patients with previously treated HER2-low metastatic breast cancer. The prioritisation of this application by the FDA and inclusion in both the Real-Time Oncology Review and Project Orbis initiatives support the importance of these data, and we look forward to working with the FDA to potentially bring Enhertu to patients with HER2-low metastatic breast cancer as quickly as possible.”
Breast cancer and HER2 expression
Breast cancer is the most common cancer and is one of the leading causes of cancer-related deaths worldwide and in the US.2,3 More than two million cases of breast cancer were diagnosed in 2020 resulting in nearly 685,000 deaths globally.2 In the US, more than 290,000 new cases are expected to be diagnosed in 2022, resulting in more than 43,000 deaths.4
HER2 is a tyrosine kinase receptor growth-promoting protein expressed on the surface of many types of tumours including breast, gastric, lung and colorectal cancers, and is one of many biomarkers expressed in breast cancer tumours.5 HER2 expression is currently defined as either positive or negative, and is determined by an IHC test which estimates the amount of HER2 protein on a cancer cell, and/or an ISH test, which counts the copies of the HER2 gene in cancer cells.5,6
HER2-positive cancers are defined as IHC 3+, IHC 2+/ISH+, and HER2-negative cancers are currently defined as IHC 0, IHC 1+ or IHC 2+/ISH-.5 Approximately half of all patients with breast cancer have tumours with low HER2 expression, with a HER2 IHC score of 1+, or a HER2 IHC score of 2+ in combination with a negative ISH test, an expression level not currently eligible for HER2-targeted therapy.7-10 Low HER2 expression occurs in both HR-positive and HR-negative disease.11
Daiichi Sankyo collaboration
Daiichi Sankyo Company, Limited (TSE: 4568) [referred to as Daiichi Sankyo] and AstraZeneca entered into a global collaboration to jointly develop and commercialise Enhertu (a HER2-directed ADC) in March 2019, and datopotamab deruxtecan (DS-1062; a TROP2-directed ADC) in July 2020, except in Japan where Daiichi Sankyo maintains exclusive rights. Daiichi Sankyo is responsible for the manufacturing and supply of Enhertu and datopotamab deruxtecan.
AstraZeneca in breast cancer
Driven by a growing understanding of breast cancer biology, AstraZeneca is challenging and redefining the current clinical paradigm for how breast cancer is classified and treated to deliver even more treatments to patients in need – with the bold ambition to one day eliminate breast cancer as a cause of death.
AstraZeneca has a comprehensive portfolio of approved and promising compounds in development that leverage different mechanisms of action to address the biologically diverse breast cancer tumour environment.
AstraZeneca aims to continue to transform outcomes for HR-positive breast cancer with foundational medicines Faslodex (fulvestrant) and Zoladex (goserelin) and the next-generation oral selective oestrogen receptor degrader (SERD) and potential new medicine camizestrant.
AstraZeneca in oncology
AstraZeneca is leading a revolution in oncology with the ambition to provide cures for cancer in every form, following the science to understand cancer and all its complexities to discover, develop and deliver life-changing medicines to patients.
The Company’s focus is on some of the most challenging cancers. It is through persistent innovation that AstraZeneca has built one of the most diverse portfolios and pipelines in the industry, with the potential to catalyse changes in the practice of medicine and transform the patient experience.
AstraZeneca has the vision to redefine cancer care and, one day, eliminate cancer as a cause of death.
AstraZeneca (LSE/STO/Nasdaq: AZN) is a global, science-led biopharmaceutical company that focuses on the discovery, development, and commercialisation of prescription medicines in Oncology, Rare Diseases, and BioPharmaceuticals, including Cardiovascular, Renal & Metabolism, and Respiratory & Immunology. Based in Cambridge, UK, AstraZeneca operates in over 100 countries and its innovative medicines are used by millions of patients worldwide.