On November 21, 2025, the World Health Organization (WHO) released an updated WHO Position Paper on varicella vaccines, replacing the previous 2014 version.

Naviva Group is the authorized distributor and supplier of the varicella vaccine Barycela Inj. which contains the MAV/06 strain.

The document provides updated global guidance on varicella vaccination, emphasizing a two-dose vaccination schedule to achieve optimal immunity. It also validates the inclusion of the new MAV/06 vaccine strain developed by GC Biopharma (South Korea), allows interchangeability between vaccines containing this strain and those using the commonly used Oka strain, and supports the introduction of vaccines containing the new strain into national immunization programs in regions with a high disease burden, as part of disease control strategies.

Key Updates and Recommendations in the WHO Position Paper:

– Validation of a new vaccine strain: The guideline officially confirms that the MAV/06 strain (used in GC Biopharma’s BARYCELA vaccine) is equivalent to the Oka strain, helping to expand global vaccine supply and enabling its inclusion and integration into existing immunization schedules.

– Two-dose vaccination schedule: The guideline emphasizes that while a single dose provides good protection, two doses result in a more durable and optimal immune response. This standard schedule has already been implemented in several countries, including the United Kingdom.

– Public health strategy: The guideline reaffirms that varicella vaccination is the primary intervention for reducing severe disease and complications, and supports the implementation of varicella vaccination within Expanded Program on Immunization (EPI) schedules for children in regions where varicella remains a major public health concern.

– Replacement of the 2014 guideline: The new document updates the 2014 recommendations by incorporating new scientific evidence and global implementation experience.

The MAV/06 varicella vaccine strain developed by GC Biopharma has been validated in the WHO Position Paper on Varicella Vaccines

– Formally recognized by WHO as a standard varicella vaccine strain alongside the widely used Oka strain

– Interchangeability between strains is validated, strengthening global vaccine supply and ensuring vaccine security

The MAV/06 strain was officially included in the WHO Position Paper on Varicella Vaccination, published on November 21, 2025.

The WHO Position Paper on vaccines is regarded as a globally endorsed reference for immunization policies, developed by the Strategic Advisory Group of Experts on Immunization (SAGE).

With its inclusion in the WHO guideline, BARYCELA Inj., GC Biopharma’s varicella vaccine containing the MAV/06 strain, has achieved international recognition as equivalent to varicella vaccines based on the Oka strain. WHO has also confirmed the interchangeability between MAV/06- and Oka-based vaccines, allowing BARYCELA Inj. to be administered alongside currently available varicella vaccines within a two-dose immunization schedule. BARYCELA Inj. is therefore considered a validated alternative vaccine in the global varicella vaccine market.

The safety and immunogenicity of the MAV/06 strain have been demonstrated in Phase III clinical trials of BARYCELA Inj. and published in reputable international journals. The studies show strong immune responses and a favorable safety profile, supporting the vaccine’s inclusion in national immunization programs.

The validation of the new strain contributes to a more flexible global vaccine supply system by enabling strain interchangeability, thereby reducing the risk of supply shortages and improving supply continuity.

Ms. Jaewoo Lee, Head of Regulatory Science and Product Development at GC Biopharma, stated: “The inclusion of the MAV/06 strain in the WHO guideline for varicella vaccines marks an important milestone in strengthening the global supply of varicella vaccines. With our proven manufacturing capacity and strong international supply capabilities, we are committed to supporting global immunization efforts by ensuring reliable access to high-quality vaccines.”

The MAV/06 strain, independently developed by GC Biopharma in 1993, has been used for nearly 30 years in products such as Suduvax, Varicella, and most recently BARYCELA Inj.

In Vietnam, NAVIVA GROUP is the authorized distributor and supplier of BARYCELA Inj., the varicella vaccine containing the MAV/06 strain.

Source: Lao Dong Newspaper