Flashtalk 25th International Pathogenic Neisseria Conference 2026

Breadth of coverage of the bivalent factor H binding protein meningococcal group B vaccine (#108)

Ray Borrow 1 , Lefteris Zolotas 2 , Ala-Eddine Deghmane 3 , James Conway 4 , Kayla Weiss 5 , Raffaella Ianotamasi 6 , Paolo Bonanni 7 , Jamie Findlow 8
  1. Meningococcal Reference Unit, UK Health Security Agency, Manchester Royal Infirmary, Manchester, UK
  2. Vaccine Research and Development, , Pfizer Ltd, Marlow, UK
  3. Invasive Bacterial Infections Unit and National Reference Centre for Meningococci and Haemophilus influenzae, Institut Pasteur, Université Paris Cité, Paris, France
  4. Department of Pediatrics, The University of Wisconsin-Madison School of Medicine & Public Health, Maison, WI, USA
  5. Vaccine Research and Development, Pfizer Inc, Pearl River, NY, USA
  6. Global Vaccines Medical Affairs, Pfizer srl, Milan, Italy
  7. Department of Health Sciences, University of Florence, Florence, Italy
  8. Global Vaccines Medical Affairs, Pfizer Ltd, Tadworth, Surrey, UK

Background: There is substantial diversity among meningococcal serogroup B (MenB) surface proteins, which makes it essential to assess the breadth of coverage (BoC) of protein-based MenB vaccines against strains that cause invasive meningococcal disease (IMD). Demonstrating this breadth of strain coverage is fundamental to the licensure and the successful real-world utilization of these vaccines to meet public health needs.

Methods: We have summarized key data generated from the serum bactericidal antibody assay with human complement (hSBA), the qualitative endogenous complement hSBA assay (enc-hSBA) and the hSBA-validated Meningococcal Antigen Surface Expression (MEASURE) assay to assess the BoC of the bivalent factor H binding protein (fHbp) MenB vaccine (MenB-fHbp; Trumenba®) across 3126 disease-causing strains. An hSBA titre ≥1:4 is the established correlate of protection for IMD.

Results: Broad protection with MenB-fHbp was demonstrated across multiple studies, with robust hSBA responses observed using conservative endpoints across 4 primary, randomly selected, vaccine-heterologous, diverse, low-to-medium fHbp‒expressing, epidemiologically relevant MenB test strains (ie, A22/A56/B24/B44). Among participants 10–25 years of age, 67%–95% had ≥4-fold rise in hSBA titre and 74% achieved composite seroprotection (ie, hSBA titre ≥1:8 [A56/B24/B44] and hSBA titre ≥1:16 [A22]). Across 10 additional MenB strains (ie, A06/A07/A12/A15/A19/A29/B03/B09/B15/B16), 71%–97% of participants had seroprotective hSBA titres. Following licensure, hSBA responses using sera from MenB-fHbp‒vaccinated individuals demonstrated extensive BoC against 14 US, Canadian, and Norwegian endemic and outbreak isolates (1976−2016), 6 French outbreak isolates (2011−2015), 3 UK outbreak isolates (2021−2025), and 6 non-MenB strains. The qualitative enc-hSBA assay assessed 144 MenB strains and 412 paired (baseline and post-vaccination) serum samples from 7 countries representative of fHbp diversity (2000−2022). Overall, 93.6% of participants with baseline titres <1:4 had titres ≥1:4 after receiving MenB-fHbp−containing vaccines. Further evaluation using the conservative MEASURE assay predicted that 90.1% of 3060 MenB isolates from 9 countries (2000−2022) were highly likely to be susceptible to killing by MenB-fHbp−elicited antibodies based on fHbp expression levels.

Conclusion: Overall, complementary and robust methods employed during MenB-fHbp clinical development and after licensure demonstrated broad BoC for MenB-fHbp−containing vaccines against diverse disease-causing MenB strains.

Sponsored by Pfizer Inc.