Ӱҵ. (Headquarters: Tokyo, CEO: Haruo Naito, “Eisai”) announced today that it has entered into an agreement to divest its rights for vertigo and equilibrium disturbance treatment Merislon® (generic name: betahistine mesilate) and muscle relaxant Myonal® (generic name: eperisone hydrochloride) in Japan to Kaken Pharmaceutical Co., Ltd. (Headquarters: Tokyo, “Kaken”).


Merislon and Myonal have been widely used by patients in Japan for a long time since their launch in 1969 and 1983, respectively. Ӱҵhas determined that divesting rights for these products to Kaken, which has strengths in the products’ disease areas, is the most optimal choice to ensure them to continue contributing to a greater number of patients. Under the terms of the agreement, Ӱҵwill receive 3.8 billion yen for the transfer, and proceed with transfer of the marketing capability by March 2025, followed by the transfer of the manufacturing and marketing approval. Ӱҵanticipates no changes to its consolidated financial forecast for the period ending March 31, 2024.


Driven by our hhc concept, Ӱҵstrives to create and deliver innovative products to target diseases with high unmet medical needs, with a particular focus in our strategic areas: Neurology, Oncology and Global Health. As an hhceco company, Ӱҵaims to effectively achieve social good in the form of relieving anxiety over health and reducing health disparities by creating solutions through building an ecosystem in collaboration with other industries.



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[Notes to editors]

  1. 1.  About Kaken Pharmaceutical Co., Ltd.

Kaken Pharmaceutical Co., Ltd. (“Kaken”) is a pharmaceutical company, established in 1948, and its corporate philosophy is to help improve the quality of life of patients by serving as many people as possible to return smiles of happiness to their faces, through supplying superior pharmaceuticals. Kaken is an R&D-driven pharmaceutical company focusing on dermatology and orthopedics, and are committed to creating and providing innovative medicines to bring smiles to the faces of patients, their families, and the medical professionals involved in their treatment.


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