FDA Panel Backs New COVID Vaccines Aimed at Dominant Strain

The FDA’s Vaccines and Related Biological Products Advisory Committee (VRBPAC) voted 8-0 with one abstention to recommend a monovalent XFG vaccine for the 2026-2027 COVID-19 season, despite concerns about the BA.3.2 variant’s potential resurgence. Experts noted XFG’s strong immunogenicity against dominant JN.1 variants but acknowledged limited effectiveness against BA.3.2, raising questions about surveillance and strain selection timing." "article": "The FDA’s Vaccines and Related Biological Products Advisory Committee (VRBPAC) voted 8-0, with one abstention, to endorse a monovalent XFG vaccine for the 2026-2027 COVID-19 season. The decision prioritized XFG, currently the most common strain in the U.S., though discussions highlighted lingering concerns about the BA.3.2 variant, which has previously dominated in Germany and South Africa. Anna Durbin of Johns Hopkins noted XFG’s immunogenicity was strong but urged vigilant surveillance, as BA.3.2 remains a potential threat. The World Health Organization had recommended the LP.8.1 strain for next year’s vaccines, which Moderna and Pfizer’s existing shots already target. However, VRBPAC chair Stanley Perlman cited Sanofi’s development of an XFG-based vaccine as a key factor, arguing its similarity to LP.8.1 made it a viable U.S. choice. Sanofi’s Nuvaxovid, a protein subunit vaccine, differs from mRNA-based competitors in production time. Hana El Sahly of Baylor College of Medicine abstained, arguing XFG’s coverage against BA.3.2 and NB.1.8.1 could be insufficient, particularly for children who drive respiratory virus transmission. She warned that if BA.3.2 mutates and spreads, current vaccines may offer limited protection. Experts also questioned whether late spring was the optimal time for strain selection, given COVID-19’s dual summer/fall and winter surge patterns. Immunogenicity data from Moderna, Pfizer, and Sanofi showed XFG vaccines generated strong neutralizing antibodies against JN.1 variants but weaker responses to BA.3.2. Testing of BA.3.2-specific vaccines demonstrated better neutralization of that strain, though at the expense of reduced effectiveness against JN.1. Flor Munoz-Rivas of Baylor emphasized the need for improved epidemiologic and genomic surveillance to guide future decisions. The meeting opened with CDC presentations on COVID-19 epidemiology and vaccine effectiveness, including suppressed interim data. Concerns were raised about relying on limited surveillance to predict emerging variants, with experts stressing the importance of adaptive strategies as new strains evolve.