Tokyo - Daiichi Sankyo Company, Limited (hereafter, Daiichi Sankyo) today announced the launch of ENHERTU (trastuzumab deruxtecan), a HER2 directed antibody drug conjugate (ADC), in Japan for the treatment of patients with HER2 positive unresectable or recurrent breast cancer after prior chemotherapy (limit the use to patients who are refractory or intolerant to standard treatments).
Marketing approval of ENHERTU by Japan's Ministry of Health, Labor, and Welfare (MHLW) in March 2020 was based on the results of the open-label, single-arm, pivotal phase 2 DESTINY-Breast01 trial that demonstrated a confirmed objective response rate of 64.1% [95% CI: 56.3-71.3] in the response evaluable set of 107 of 167 patients, which included 26 Japanese women, at a data cut-off of March 21, 2019. Data from the DESTINY-Breast01 trial were published in The New England Journal of Medicine.
'Now patients in Japan with HER2 positive metastatic breast cancer who progress following treatment with at least two HER2 directed therapies and chemotherapy have access to ENHERTU, an important new medicine that may transform the way these patients are treated. We are proud of how quickly we have delivered ENHERTU, making it available only four years after treating the first patient in Japan,' said Hideaki Noji, Vice President, Head of Specialty Marketing in Japan, Daiichi Sankyo. 'ENHERTU also represents the second innovative oncology medicine to be launched in Japan from the oncology pipeline of Daiichi Sankyo in the past year, another milestone we are honored to have achieved.'
Safety and efficacy of ENHERTU (5.4 mg/kg) in patients without prior trastuzumab, taxane and trastuzumab emtansine treatment have not been established. ENHERTU is approved in Japan with a Warning for Interstitial Lung Disease (ILD). As cases of ILD, including fatal cases, have occurred in ENHERTU-treated patients, ENHERTU is to be used in close collaboration with a respiratory disease expert. Closely observe patients during therapy by monitoring for early signs or symptoms of ILD (such as dyspnea, cough or fever) and regularly perform peripheral artery oxygen saturation (SpO2) tests, chest X-ray scans and chest CT scans. If abnormalities are observed, discontinue administration of ENHERTU, and take appropriate measures such as corticosteroid administration. Prior to initiation of ENHERTU therapy, perform a chest CT scan and interview to confirm the absence of any comorbidity or history of ILD with the patient, and carefully consider the eligibility of the patient for ENHERTU therapy.
Adverse reactions (from ENHERTU Japan Prescribing Information) occurred in 182 of 184 patients (98.9%) who received ENHERTU. The most common adverse reactions were nausea in 140 patients (76.1%), alopecia in 85 patients (46.2%), fatigue in 81 patients (44.0%), vomiting in 78 patients (42.4%), neutrophil count decreased in 55 patients (29.9%), decreased appetite in 52 patients (28.3%), anemia in 40 patients (21.7%) and diarrhea in 40 patients (21.7%). Overall incidence of ILD was 8.2%. ILD occurred in 23% of Japanese patients (7 out of 30) with no grade 3 or above events including no ILD-related deaths.
About ENHERTU
ENHERTU (trastuzumab deruxtecan outside the U.S.; fam-trastuzumab deruxtecan-nxki in the U.S. only), is the lead ADC in the oncology portfolio of Daiichi Sankyo and the most advanced program in AstraZeneca's ADC Scientific platform.
ADCs are targeted cancer medicines that deliver cytotoxic chemotherapy ('payload') to cancer cells via a linker attached to a monoclonal antibody that binds to a specific target expressed on cancer cells. Designed using Daiichi Sankyo's proprietary DXd ADC technology, ENHERTU is comprised of a HER2 monoclonal antibody attached to a topoisomerase I inhibitor payload by a tetrapeptide-based linker.
ENHERTU has been approved for use only in the U.S. and Japan. ENHERTU has not been approved in the EU, or countries outside of Japan and the United States, for any indication. It is an investigational agent globally for various indications.
About the ENHERTU Clinical Development Program
A comprehensive development program for ENHERTU is underway globally with six pivotal trials evaluating the efficacy and safety of ENHERTU monotherapy across multiple HER2 targetable cancers including breast, gastric and lung cancers. Trials in combination with other anticancer treatments, such as immunotherapy, also are underway.
About the Collaboration between Daiichi Sankyo and AstraZeneca
In March 2019, Daiichi Sankyo and AstraZeneca entered into a global collaboration to jointly develop and commercialize ENHERTU, except in Japan where Daiichi Sankyo maintains exclusive rights. Daiichi Sankyo is solely responsible for the manufacturing and supply.
U.S. FDA-Approved Indication for ENHERTU
ENHERTU is a HER2-directed antibody and topoisomerase inhibitor conjugate indicated for the treatment of adult patients with unresectable or metastatic HER2-positive breast cancer who have received two or more prior anti-HER2-based regimens in the metastatic setting.
This indication is approved under accelerated approval based on tumor response rate and duration of response. Continued approval for this indication may be contingent upon verification and description of clinical benefit in a confirmatory trial.
About Daiichi Sankyo
Daiichi Sankyo Group is dedicated to the creation and supply of innovative pharmaceutical therapies to improve standards of care and address diversified, unmet medical needs of people globally by leveraging our world-class science and technology. With more than 100 years of scientific expertise and a presence in more than 20 countries, Daiichi Sankyo and its 15,000 employees around the world draw upon a rich legacy of innovation and a robust pipeline of promising new medicines to help people. In addition to a strong portfolio of medicines for cardiovascular diseases, under the Group's 2025 Vision to become a 'Global Pharma Innovator with Competitive Advantage in Oncology.' Daiichi Sankyo is primarily focused on providing novel therapies in oncology, as well as other research areas centered around rare diseases and immune disorders.
Contact:
Jennifer Brennan
Tel: +1 908 992 6631
Email: jbrennan2@dsi.com
DAIICHI SANKYO CO., LTD. 
