DNDi and Serum Institute of India Partner to Launch Global Phase III Trial for Dengue Monoclonal Antibody
Key Insights
The Drugs for Neglected Diseases initiative (DNDi) and Serum Institute of India (SII) have signed a licensing agreement to advance a monoclonal antibody dengue (search) treatment into Phase III trials.
The 1,000-participant study is expected to begin in Q1 2027 across Malaysia, Thailand, and Brazil, with SII supplying the investigational drug.
The antibody, formerly known as VIS513, targets all four dengue (search) virus serotypes and has shown promising safety and efficacy in earlier trials.
The Drugs for Neglected Diseases initiative (DNDi) and the Serum Institute of India (SII) have finalized a licensing agreement that clears the path for a global Phase III clinical trial of an SII-developed monoclonal antibody treatment for dengue (search). The study, which will enroll 1,000 participants, is expected to commence in the first quarter of 2027 across Malaysia, Thailand, and Brazil — all countries where the mosquito-borne viral infection is endemic.
The investigational therapy, formerly known as VIS513, was originally developed by Visterra (search), a subsidiary of Otsuka (search). SII has since developed and optimized the current formulation, conducting preclinical studies as well as Phase I and II clinical trials that delivered promising safety and efficacy results. The company is already leading a pivotal Phase III trial of the antibody in India.
Targeting All Four Dengue (search) Serotypes
VIS513 targets an epitope on the dengue (search) virus and has demonstrated the ability to neutralize all four serotypes (DENV-1 to 4). This broad-spectrum activity is particularly significant given that existing vaccines face usage restrictions, including being limited to individuals with prior dengue infection and lacking protective efficacy against some serotypes.
Currently, there is no specific treatment for dengue (search) beyond hydration, clinical monitoring, and symptom management. The disease, transmitted through the bites of infected Aedes mosquitoes, causes flu-like symptoms including high fever, severe headache, muscle and joint pain, and rash. In some cases, it can progress to a life-threatening severe form.
Trial Design and Funding
For the DNDi-led Phase III trial, SII will supply study medicines and manage their refrigerated transportation to clinical trial sites. The participating institutions in Malaysia, Thailand, and Brazil are members of the Dengue (search) Alliance, a global partnership of dengue-endemic countries working to develop effective and accessible treatments.
The trial is being conducted with financial support from the European Commission's Directorate-General for Health Emergency Preparedness and Response Authority (DG HERA) in partnership with the French Development Agency (search) (AFD). In November 2025, DG HERA announced an investment of €20 million to advance the development of two new dengue (search) medicines.
A Growing Global Threat
The World Health Organization has estimated that dengue (search) infects approximately 390 million people each year and results in 20,000 deaths. The disease is endemic in more than 125 countries, including the US territories of Puerto Rico, the US Virgin Islands, and American Samoa, and is a leading cause of fever among travelers to Latin America, the Caribbean, and Southeast Asia. Fueled by climate change and globalization, dengue is expanding to many other parts of the world, including Europe.
"Serum Institute of India is committed to go all out in controlling dengue (search)," said Dr. Rajeev Dhere, a senior scientific advisor at SII. "We are working on both preventive and therapeutic applications to protect populations in dengue-endemic areas [and] will make all attempts to develop, produce, and distribute the vaccine and monoclonal antibodies all over the globe in an affordable manner."
Monoclonal antibodies are currently among the most advanced dengue (search) treatment candidates, and this partnership between a leading vaccine manufacturer and a non-profit R&D organization represents a significant step toward addressing a disease that has long suffered from a lack of therapeutic options.