Haihe Biopharma enters into exclusive license agreement with Taiho Pharma for PI3Kα inhibitor risovalisib (CYH33) in Japan

Haihe Biopharma Co., Ltd. ("Haihe") and Taiho Pharmaceutical Co., Ltd. ("Taiho") announced today that the two companies have entered into an exclusive license agreement regarding the development, manufacturing and commercialization of the PI3Kα (phosphatidylinositol 3-kinase alpha) inhibitor risovalisib (international nonproprietary name; development code: CYH33). Risovalisib is currently being submitted for manufacturing and marketing approval in Japan as a treatment for ovarian clear cell carcinoma by Haihe Biopharma K.K., a fully owned affiliate of Haihe.

Under the license agreement, Haihe will receive an upfront payment, development and sales milestone payments, and royalties based on sales revenue from Taiho, and Taiho will obtain exclusive rights in Japan to develop, manufacture and commercialize risovalisib.

Risovalisib is a novel, selective PI3Kα inhibitor developed by Haihe. In Japan, Haihe Biopharma K.K. submitted a New Drug Application in August 2025 for the anticipated indication of "advanced or recurrent ovarian clear cell carcinoma harboring PIK3CA gene mutations that has progressed after chemotherapy." Risovalisib was granted orphan drug designation by the Ministry of Health, Labour and Welfare in June 2025 in Japan.

Dr. Jian Ding from Haihe,  stated: "We are pleased to announce that we are entering into a partnership with Taiho, one of the leading oncology companies in Japan, regarding the PI3Kα inhibitor risovalisib. We hope our collaboration will be able to provide a promising treatment option for patients with ovarian clear cell carcinoma and other PI3Kα-associated diseases."

Masayuki Kobayashi, President and Representative Director of Taiho, stated: "We are pleased to announce that we will be entering into this partnership with Haihe, with whom we have already built a strong collaborative relationship. Through risovalisib, a new treatment option for patients with ovarian clear cell carcinoma, we will continue to work together with Haihe to further contribute to patients and healthcare professionals."