GC Biopharma said it has won the largest share in the Korea Disease Control and Prevention Agency’s (KDCA) national procurement bid for the 2025–2026 seasonal influenza vaccine. The company will supply 2.63 million doses, the highest volume awarded in the tender.

The KDCA bid, part of Korea’s National Immunization Program (NIP), marks the official adoption of trivalent influenza vaccines for the upcoming season, in alignment with updated recommendations from the World Health Organization (WHO).

The WHO in February advised that vaccines for the Northern Hemisphere contain two strains of influenza A (H1N1 and H3N2) and one strain of influenza B (Victoria lineage), effectively shifting away from quadrivalent formulations that previously included an additional B/Yamagata strain.

Since March 2020, there have been no naturally occurring cases of the B/Yamagata virus lineage reported worldwide. The WHO and other global health authorities, including the U.S. Centers for Disease Control and Prevention (CDC), have acknowledged that the B/Yamagata strain is likely extinct.

Consequently, global vaccine manufacturers began transitioning to trivalent formulations starting with the 2024–2025 flu season, with no observed compromise in vaccine efficacy.

“Global experts have assessed that, with the B/Yamagata strain no longer circulating, there is no significant difference in protection between trivalent and quadrivalent vaccines,” GC said in a statement.

The company has consistently supplied influenza vaccines to the national program and played a pivotal role in ensuring public health stability, including during the Covid-19 pandemic when it maintained uninterrupted vaccine distribution.

“We are committed to safeguarding public health by reliably providing WHO-recommended, globally standardized vaccines in Korea,” a GC official said.