(Yicai) July 23 – Haisco Pharmaceutical Group has achieved a major regulatory milestone with the approval of China’s first small-molecule drug for treating a rare, life-threatening blood disorder. Just last month, the Chinese drugmaker licensed the exclusive rights for this new therapy in certain global markets to Nasdaq-listed Nuvectis Pharma.

Sipupopan Succinate, developed to treat adults with paroxysmal nocturnal hemoglobinuria who have not previously received complement inhibitor therapy, was approved by Chinese regulators today, Chengdu-based Haisco announced at noon. A marketing application covering the drug’s use for a broader range of PNH patients is undergoing regulatory technical review, it added.

PNH is a rare, acquired stem cell disorder affecting the formation and development of red blood cell components. Defects in the red blood cell membrane cause the complement system, which is part of the body’s immune system, to continuously attack red blood cells, leading to hemolysis, or the premature destruction of erythrocytes. The condition carries a high risk of complications such as thrombosis and kidney damage, requiring long-term pharmacological management.

Sipupopan Succinate works by selectively inhibiting complement factor B, thereby interrupting the biological pathway responsible for hemolysis. It is the first orally administered complement factor B inhibitor approved in China and tackles the disease at an upstream point in the complement cascade, according to Haisco.

Clinical trial data indicate that the drug demonstrates favorable safety and tolerability. Efficacy benefits were observed consistently across multiple patient subgroups, including different ages, genders, disease durations, and baseline hemoglobin levels, with treatment effects sustained over extended periods, Haisco said.

The company’s shares [SHE: 002653] ended 1.2 percent higher at CNY72.02 (USD10.64) each today, after surging by as much as 5.9 percent at one point. The broader Shenzhen market rose 0.9 percent. The stock is up about 40 percent so far this year.

On June 23, Haisco said it had licensed the exclusive development, manufacturing, and commercialization rights for two innovative drugs in certain markets to Nuvectis. HSK39297, marketed in China as Sipupopan Succinate tablets, was one of them. Nuvectis secured the rights to HSK39297 in all territories outside China, Hong Kong, Macau, Taiwan, Southeast Asia, and India.

The agreement will take effect once Nuvectis completes its next fundraiser, after which it will pay USD40 million in upfront and near-term milestone payments, followed by as much as USD1.4 billion in additional development and commercialization milestones, as well as tiered royalties reaching the low double digits on future sales, Haisco said. 

Haisco will be entitled to a share of any proceeds should New Jersey-based Nuvectis subsequently sublicense the rights to a third party, the drugmaker noted.

Haisco’s June announcement did not disclose how the licensing payments would be allocated between the two drugs. Compared with HSK39297, which received Chinese marketing approval today, the company’s other licensed innovative drug candidate for cancer treatment remains in Phase I clinical development.

Editors: Tang Shihua, Martin Kadiev