• Officially recognized by WHO as a standard varicella vaccine strain alongside Oka
• Interchangeability endorsed, enhancing global supply security

GC Biopharma (006280.KS), a global biopharmaceutical company,  announced that its proprietary varicella vaccine strain MAV/06 has been included in the World Health Organization (WHO) Position Paper on varicella vaccination, published on November 21.

WHO Position Paper serves as the most authoritative global guidance for immunization policy, developed by the Strategic Advisory Group of Experts on Immunization (SAGE).

With this inclusion, BARYCELA Inj. — GC Biopharma's varicella vaccine based on the MAV/06 strain — has attained equivalent international recognition to Oka strain-based vaccines. The WHO also endorsed the interchangeability of MAV/06 and Oka strains, allowing BARYCELA Inj. to be vaccinated with existing varicella vaccines in two-dose immunization schedules. This positions BARYCELA Inj. as a validated alternative in the global varicella vaccine market.

The immunogenicity and safety of MAV/06 were confirmed in a Phase 3 clinical trial of BARYCELA Inj., published in a peer-reviewed journal. The study demonstrated strong immune responses and a favorable safety profile, supporting its use in national immunization programs.

The endorsement establishes a more resilient global supply framework by enabling substitution between strains, thereby minimizing the risk of supply shortage and improving vaccination continuity across markets.

GC Biopharma expects the WHO recognition to strengthen its position in global procurement platforms such as the Pan American Health Organization (PAHO), where BARYCELA Inj. has already been stably supplied for years.

"The inclusion of MAV/06 in the WHO Position Paper mark a significant milestone in strengthening global varicella vaccine supply," said Jaewoo Lee, Head of the Regulatory Science & Product Development at GC Biopharma. "With validated manufacturing capabilities and a strong track record of international supply, we're committed to supporting global immunization efforts with reliable access to high-quality vaccines."

The MAV/06 strain was developed in-house by GC Biopharma in 1993 and has been used in products such as Suduvax and BARYCELA Inj. for nearly 30 years, including supplies through PAHO to various markets.