Eisai Inc., the U.S. subsidiary of Tokyo, Japan-based Eisai Co., Ltd., has entered into a new joint research agreement with the Broad Institute, a collaborative research institute which includes researchers from the Massachusetts Institute of Technology and Harvard University, to develop a new antimalarial medicine based on anti-malarial drug targets the team identified last year.

The Eisai and Broad Joint Development Program for Antimalarial Medicines was established in September 2014 and has led to the identification and optimization of promising molecules, using hits obtained by screening Broad's compound library for antimalarials as a starting point. These compounds interact with a novel target in the malarial parasite (Phenylalanine t-RNA synthetase), which results in inhibition of protein synthesis. The compounds exhibit potent both in vitro and in vivo antimalarial activity, in the blood-, the liver- and the transmission-stages of the parasite life cycle. These results were published in the scientific journal Nature in September 2016.

"We are very encouraged by the favorable progress of our collaboration with the Broad Institute and are hopeful that it will lead to a new antimalarial medicine that will benefit the millions currently in need," said Haruo Naito, CEO of Eisai Co., Ltd. "At Eisai, we are proactively working to contribute towards global health, which we consider to be our mission and a long term investment in creating a healthy and prosperous middle-income class."

Malaria is a deadly disease caused by malarial parasites and is vector-transmitted (transmitted by an infected mosquito). According to the World Health Organization, the disease led to an estimated 430,000 deaths in 2015, mostly African children. The majority of available antimalarial medicines target the blood-stage, in which the parasites replicate within erythrocytes. There is, however, a need for medicines that target all stages of the parasite lifecycle. Parasites can also become resistant to drug treatments, and thus there is an urgent need to develop medicines that utilize new mechanisms of action.

Under this agreement, Eisai and Broad aim to generate novel compounds with improved properties by building on the base of the joint development program's results, and leveraging Broad's medicinal chemistry capabilities alongside Eisai's knowledge of pharmaceutical development. After selection of a lead optimization candidate, Eisai will have the option to an exclusive license to develop the candidate.

"If successful, this would be a novel mechanism-of-action drug that targets a protein that has never-before been targeted in anti-malarial therapeutics," said research team leader Stuart Schreiber, a founding core member of the Broad Institute and a pioneer in the field of chemical biology and novel approaches to therapeutics. "Existing drugs have been around for decades, which is one reason that resistance emerges so quickly. Eisai's commitment to working with the non-profit and academic research community to explore promising new approaches demonstrates its dedication to helping overcome a deadly medical challenge that still threatens hundreds of thousands of children in developing countries."

This joint research program is funded by the Global Health Innovative Technology Fund (GHIT Fund), an international non-profit organization headquartered in Japan.

Under its human healthcare (hhc) philosophy, Eisai is determined to be proactive in improving access to medicines worldwide through partnerships with governments, international organizations, and other non-profit private sector organizations. Through these collaborations, Eisai aims to make new treatments available as early as possible to patients with malaria, tuberculosis and neglected tropical diseases, and thereby further increasing the healthcare benefits provided to the patients and their families.