News Releases

Taiho Pharmaceutical Co., Ltd. (hereinafter “Taiho”) announced today that the PI3Kα inhibitor, HAIZEXIN_® tablets 10mg (generic name: risovalisib mesilate hydrate), has been listed on the National Health Insurance (NHI) reimbursement price list. The launch of this new product in Japan is scheduled for July 28, 2026.

In March 2026, Haihe Biopharma K. K., a fully owned affiliate of Haihe Biopharma Co., Ltd. (hereinafter “Haihe”), obtained approval to manufacture and market HAIZEXIN in Japan for the treatment of a patient with ovarian clear cell carcinoma (hereinafter “OCCC”) harboring PIK3CA gene mutations that has progressed after chemotherapy. Taiho will be responsible for sales and medical information activities for HAIZEXIN in Japan pursuant to an exclusive license agreement with Haihe, entered into in October 2025, for the development, manufacture, and commercialization of HAIZEXIN.

HAIZEXIN is a small-molecule PI3Kα inhibitor developed by Haihe. HAIZEXIN binds to the ATP-binding site of PI3Kα and inhibits its kinase activity, thereby inhibiting the phosphorylation of AKT, a downstream molecule in the PI3K signaling pathway¹, which is believed to result in antitumor effects.

Taiho and Haihe together will work with healthcare professionals to serve patients with OCCC by providing HAIZEXIN as a new treatment option.

Ovarian cancer is one of the leading causes of cancer-related death in women, with approximately 320,000 new cases diagnosed worldwide in 2022, making it the third most common gynecologic cancer.² In Japan, the number of registered ovarian cancer cases was reported to be 16,590 in 2023.³ OCCC is a histological subtype of epithelial ovarian cancer and accounts for approximately 21.9% of ovarian cancers in Japan.⁴ OCCC has a high prevalence of PIK3CA gene mutations, which are observed in approximately 30% to 40% of cases^5,6; based on this prevalence, the annual number of patients with OCCC harboring PIK3CA gene mutations is estimated to be approximately 650 to 950. OCCC is a rare cancer with limited treatment options, and there remains a need to develop new therapies.

Haihe Biopharma Co., Ltd. is a global, values-based, R&D driven biopharmaceutical leader headquartered in China with operation centers in the US and Japan, and focuses on innovative therapies. The Company has the comprehensive capability of drug discovery, development, manufacturing and commercialization, and delivers life-saving therapies to patients around the world. As an R&D focused company with many experts skilled in developing new drugs, Haihe Biopharma is committed to in-house innovation with global perspective management and R&D team. For more information about Haihe Biopharma, please visit https://www.haihepharma.com/en

Haihe Biopharma K. K. has been established as fully owned affiliate of Haihe Biopharma Co., Ltd. since 2021. The Company will introduce rich pipeline of novel anticancer drugs from Haihe Biopharma Co., Ltd. in Japan.

1. Xiang HY, Wang X, Chen YH, et al. Identification of methyl (5-(6-((4-(methylsulfonyl)piperazin-1-yl)methyl)-4-morpholinopyrrolo[2,1-f][1,2,4]triazin-2-yl)-4-(trifluoromethyl)pyridin-2-yl)carbamate (CYH33) as an orally bioavailable, highly potent, PI3Kα inhibitor for the treatment of advanced solid tumors. Eur J Med Chem. 2021;209:112913.
2. Global Cancer Observatory, 2022. https://gco.iarc.who.int/media/globocan/factsheets/cancers/25-ovary-fact-sheet.pdf
3. National Cancer Center, Cancer Information Service, Hospital-based Cancer Registry, National Aggregated Data 2023
4. Kawana K. Report of the Gynecologic Oncology Committee of the Japan Society of Obstetrics and Gynecology: Annual Report of Patients for 2021. Acta Obstetrica et Gynaecologica Japonica. 2023;75:1643–1698.
5. Yamamoto S, Tsuda H, Takano M, et al. PIK3CA mutations and loss of ARID1A protein expression are early events in the development of cystic ovarian clear cell adenocarcinoma. Virchows Arch, 2012, 460(1):77-87.
6. Itamochi H, Oishi T, Oumi N, et al. Whole-genome sequencing revealed novel prognostic biomarkers and promising targets for therapy of ovarian clear cell carcinoma. Br J Cancer, 2017, 117(5): 717-724.