[Edaily Reporter SONG YOUNG-DOO ] GCGreen Cross Corporation(006280)is accelerating the global market expansion of its in-house developed chickenpox vaccine, “Varicella.” As chickenpox vaccination programs worldwide are shifting to a two-dose regimen, the company has included South Korea in its global clinical trial locations—following Thailand and Vietnam—and has embarked on full-scale efforts to enter overseas markets.

GC Biopharma Corp. announced on the 2nd that its Investigational New Drug (IND) application for a Phase 3 clinical trial to expand the two-dose indication for Varicella-Z has been approved by the Ministry of Food and Drug Safety.

This clinical trial will be conducted on 474 healthy children aged 12 months to 12 years, adding South Korea to the global clinical trials currently underway in Thailand and Vietnam. It is designed to directly compare the immunogenicity and safety of Varicella with “Varivax,” the varicella vaccine produced by MSD in the U.S.

This head-to-head trial is seen as a strategy to objectively demonstrate the efficacy and safety of “Varicella” compared to competing products during the global approval process. The company plans to use this trial to secure the global competitiveness of “Varicella” and establish key evidence for obtaining overseas marketing authorization.

The varicella vaccine market is rapidly shifting toward a two-dose regimen. As it has been confirmed that a single dose may lead to “breakthrough infections” in some cases, 28 countries—including the United States, Canada, and Japan—have already adopted a two-dose regimen into their national immunization programs. The World Health Organization (WHO) also recommends a two-dose regimen to reduce the incidence and severity of varicella.

Industry experts anticipate that demand for these vaccines will continue to grow as more countries adopt the two-dose regimen in line with the WHO’s recommendation. In particular, since varicella vaccines account for a significant portion of National Immunization Programs (NIPs) and public procurement by international organizations, global regulatory approval is considered a key factor determining market competitiveness.

Varicella is a chickenpox vaccine based on the “MAV/06” strain, which GC Biopharma Corp. developed in-house in 1993. Last year, the MAV/06 strain was officially listed in a WHO Position Paper, securing international credibility. In particular, the paper acknowledged the compatibility of the vaccine with existing immunization systems by stating that cross-vaccination is possible between MAV/06-based vaccines and Oka-strain-based vaccines, which are widely used in the global market.

Following the completion of this multinational clinical trial, GC Biopharma Corp. aims to obtain marketing authorization for the two-dose regimen by 2028, focusing on South Korea and Southeast Asian countries where demand is rapidly increasing.

Lee Jae-woo, Head of Development at GC Biopharma Corp., stated, “The two-dose clinical trial for Varicella is an important milestone that enhances the value of our vaccine portfolio,” adding, “We will continue to expand its scope of application in both the global public procurement market and the private vaccine market.”