A potential new targeted medicine for cancer - AstraZeneca and Daiichi Sankyo collaborate on trastuzumab deruxtecan

AstraZeneca has entered into a global development and commercialisation collaboration agreement with Daiichi Sankyo Company, Limited (Daiichi Sankyo) for trastuzumab deruxtecan (DS-8201), a proprietary antibody-drug conjugate (ADC) and potential new targeted medicine for cancer treatment. The collaboration is aligned with AstraZeneca’s science-led strategy in Oncology, which is based on four key scientific platforms: tumour drivers & resistance, DNA damage response, Immuno-Oncology and ADCs.

Trastuzumab deruxtecan is currently in development for the treatment of multiple HER2-expressing cancers, including breast and gastric cancer, and in patients with HER2-low expression. In 2017, trastuzumab deruxtecan was granted Breakthrough Therapy Designation by the US FDA for the treatment of patients with HER2-positive, locally-advanced or metastatic breast cancer who have been treated with trastuzumab and pertuzumab and have disease progression after trastuzumab emtansine. A first regulatory submission is scheduled for the second half of 2019 for patients in the advanced or refractory breast cancer setting. Additional development for the treatment of breast, non-small cell lung cancer (NSCLC), gastric and colorectal cancers is ongoing.

The companies will jointly develop and commercialise trastuzumab deruxtecan worldwide, except in Japan where Daiichi Sankyo will maintain exclusive rights. Daiichi Sankyo will be solely responsible for manufacturing and supply.

Under the terms of the agreement, AstraZeneca will pay Daiichi Sankyo an upfront payment of $1.35 billion, half of which is due upon execution, with the remainder payable 12 months later. Contingent payments of up to $5.55 billion include $3.8 billion for potential successful achievement of future regulatory and other milestones, as well as $1.75 billion for sales-related milestones. AstraZeneca and Daiichi Sankyo will share equally development and commercialisation costs as well as profits from trastuzumab deruxtecan worldwide, except for Japan. Daiichi Sankyo will record sales in the US, certain countries in Europe and certain other markets where Daiichi Sankyo has affiliates..

Comment:HER2 is a tyrosine kinase receptor growth-promoting protein found on the surface of some cancer cells that is associated with aggressive disease and poorer prognosis. A number of HER2 targeting therapies are approved to treat HER2 positive metastatic breast cancer and have improved survival rates. The remaining 80 percent of breast cancers are classified as HER2 negative; however, over 40 percent still express some level of HER2 as a cell surface antigen and as measured by immunohistochemistry (IHC). No anti-HER2 agents are indicated for these low expressing tumors, which may be defined as IHC 2+/ISH- or IHC 1+.2