SK bioscience, a South Korea-based global vaccine and biotech innovator, has filed an Investigational New Drug (IND) application with the Ministry of Food and Drug Safety to initiate a global Phase 3 clinical trial of SKYVaricella. The study aims to add a two-dose indication, aligning with evolving international standards that increasingly recommend two doses to provide stronger, longer-lasting protection against varicella.

The trial will evaluate the immunogenicity and safety of a 2-shot varicella vaccine in roughly 800 children aged 12 months to 12 years, with completion targeted by 2027.

Ryu Ji-hwa, Head of the Development Department of SK bioscience, said, "Our 2-dose varicella vaccine is a strategic pipeline that directly reflects updated international standards and rising market demand. Building on our WHO PQ-backed procurement experience and R&D achievements, we aim to complete development quickly and compete globally with reliable production and superior immunogenicity."  

Varicella vaccines have effectively reduced the incidence of disease and complications with a single dose, which has been the standard in many countries. However, as breakthrough infections may occur over time, international standards are shifting toward a 2-dose schedule to provide stronger, longer-lasting immunity and reduce community transmission.  

WHO's SAGE (Strategic Advisory Group of Experts on Immunisation) officially recommended a 2-dose varicella vaccination in March 2025, boosting demand in global procurement markets, including PAHO. The United States implemented a 2-dose schedule in 2006, cutting varicella incidence by over 85 percent, and countries such as Germany and Japan have since incorporated 2-dose regimens into their national immunisation programmes.

SKYVaricella was launched in Korea in 2018 and obtained WHO PQ certification in 2019, becoming the second vaccine worldwide to achieve this, and entered the international procurement market. It has been administered to over five million people globally, with supply expanded through Korea's National Immunisation Programme, private healthcare providers, and international tenders such as PAHO. Recently, the company signed an additional supply agreement with PAHO for 2025-2027 and plans to accelerate its entry into the global varicella vaccine market through the development of SKYVaricella 2-dose regimen.

Global Market Insights has projected that the global varicella vaccine market will grow from USD 3.4 billion in 2024 to USD 6.3 billion by 2034, at an average annual growth rate of 6.5 percent.