HBI-8000 is an oral HDAC inhibitor approved in China for use in the treatment of peripheral T-cell lymphoma (PTCL). Non-clinical data suggest HBI-8000 has epigenetic properties that work to regulate tumor cell growth, and the agent is believed to have immunomodulatory properties as well. HBI-8000 is at the clinical stage of testing in Japan as a treatment for PTCL, a type of non-Hodgkin's lymphoma, under orphan drug designation from the regulatory authority in Japan. Meanwhile, a Phase I clinical study of the agent in solid tumors has been completed in the U.S.
Eisai has exclusive rights to develop and market HBI-8000 in the licensed territories. However, for PTCL and adult T-cell leukemia-lymphoma, HUYA will complete development of the agent for these indications and Eisai will be responsible for commercialization. Eisai will pay HUYA upfront, development and commercial milestone payments as well as royalties over the term of the license, respectively.