China Medical System Holdings Limited (“CMS” or the “Group”) is pleased to announce that on 22 September 2025, the Group through its subsidiaries entered into two separate exclusive Collaboration Agreements (the “Agreements”) with Chongqing Genrix Biopharmaceutical Co., Ltd. (“Genrix Bio”) for two Class 1 therapeutic biological products, Vecantoxatug Injection (GR2001, “Vecantoxatug”) indicated for passive immunization against tetanus and Silevimig Injection (GR1801, “Silevimig”) indicated for passive immunization following suspected rabies virus exposure, respectively. In accordance with the Agreements, the Group has obtained exclusive commercialization rights for these two products in mainland China and exclusive licensing rights for the rest of the Asia-Pacific region, the Middle East and North Africa. The collaboration terms respectively extend until ten years after these two products receive their marketing approvals in Mainland China (the “Initial Term for each Product”). Unless terminated or dissolved under the terms set forth in the Agreements, the Agreements will automatically renew for successive ten-year periods upon expiration of the Initial Term for each Product.

Vecantoxatug is a passive immunization agent with an excellent safety profile, which delivers superior protection compared with human tetanus immunoglobulin (HTIG), providing rapid and durable immune defense for patients. Its Phase III clinical trial for passive immunization against tetanus successfully met the primary efficacy endpoint. In May 2024, Vecantoxatug was designated Breakthrough Therapy by the Center for Drug Evaluation (CDE) of the National Medical Products Administration (NMPA). On 22 May 2025, its New Drug Application (NDA) was formally accepted by the CDE.

Silevimig is the world’s first recombinant, fully human bispecific antibody against rabies virus (RABV) targeting epitope I and/or epitope III of the rabies virus glycoprotein, developed in accordance with the World Health Organization (WHO) recommended “cocktail” therapeutic option targeting distinct antigenic sites. It can be manufactured at scale with standardized, and also demonstrates broad neutralization, low immunogenicity, minimal interference with vaccine-induced active immunity, and controlled production cost. On 14 January 2025, its NDA for use in adults requiring passive immunization following suspected rabies virus exposure was formally accepted by CDE. In addition, in July 2025, the NMPA approved the clinical trial application for Silevimig in children and adolescents aged 2 to <18 years requiring passive immunization following suspected rabies virus exposure. This Phase III clinical trial is currently in progress.

CMS has always been committed to deploying innovative products with clinical value and differentiated advantages. The market for tetanus and rabies passive immunization remains substantial, yet existing passive immunization products are constrained by safety and accessibility concerns. If approved, Vecantoxatug and Silevimig will provide new preventive and therapeutic options of passive immunization for patients following tetanus and rabies exposure. Additionally, they will synergize with the Group’s existing products in expert networks and market resources, bringing benefit to patients.