Oral Presentation 25th International Pathogenic Neisseria Conference 2026

Meningococcal B (4CMenB) vaccination for the prevention of gonorrhoea in men who have sex with men: the GoGoVax randomised placebo-controlled trial   (138785)

Kate L Seib 1 , Basil Donovan 2 , Fengyi Jin 2 , Caroline Thng 1 3 , Barbara Yeung 2 , Nicholas Comninos 4 , Rohan I Bopage 4 , Anik Ray 5 , Alison Mahony 5 , Eric PF Chow 6 7 8 , Marcus Y Chen 6 8 , Kate Maddaford 6 , Helen Lau 9 , Protia Westall 2 , Dan Lu 2 , Benjamin R Bavinton 2 , Kathy Petoumenos 2 , David M Whiley 10 , Michael P Jennings 1 , Amy V Jennison 11 , John Kaldor 2 , Rebecca Guy 2 , Monica M Lahra 12 13 , Jane Costello 14 , Brent Mackie 15 , David J Templeton 2 16 17 , Beng Eu 18 , Mark O’Reilly 19 , Christopher K Fairley 6 8 , Anna McNulty 5 20 , Rick Varma 2 5 , David Lewis 4 21 , Andrew E Grulich 2
  1. Institute for Biomedicine and Glycomics, Griffith University, Gold Coast, QLD, Australia
  2. The Kirby Institute, UNSW, Sydney, NSW, Australia
  3. Gold Coast Sexual Health, Gold Coast Hospital and Health Service, Southport, QLD, Australia
  4. Western Sydney Sexual Health Centre, Parramatta, NSW, Australia
  5. Sydney Sexual Health Centre, Sydney, NSW, Australia
  6. Melbourne Sexual Health Centre, Bayside Health, Melbourne, VIC, Australia
  7. Melbourne School of Population and Global Health, The University of Melbourne, Melbourne, VIC, Australia
  8. School of Translational Medicine, Faculty of Medicine, Nursing and Health Sciences, Monash University, Melbourne, VIC, Australia
  9. Prahran Market Clinic, Melbourne, VIC, Australia
  10. UQ Centre for Clinical Research, Faculty of Medicine, The University of Queensland, Brisbane, QLD, Australia
  11. Public and Environmental Health, Pathology Queensland, Queensland Health, Brisbane, QLD, Australia
  12. WHO Collaborating Centre for STI and AMR, NSW Health Pathology Microbiology, The Prince of Wales Hospital, Sydney, NSW, Australia
  13. The University of New South Wales, Sydney, NSW, Australia
  14. Positive Life NSW, Sydney, NSW, Australia
  15. ACON Health, Sydeny, NSW, Australia
  16. RPA Sexual Health, Department of Sexual Health Medicine, Community Health, Sydney Local Health District, Sydney, NSW, Australia
  17. Central Clinical School, Faculty of Medicine and Health, University of Sydney, Sydney, NSW, Australia
  18. Prahran Market Clinic, Melbourne, VIC, Australia
  19. Taylor Square Private Clinic, Sydeny, NSW, Australia
  20. School of Population Health, University of New South Wales, Sydney, NSW, Australia
  21. Sydney Medical School-Westmead, Faculty of Medicine and Health and Sydney Infectious Diseases Institute, University of Sydney, Westmead, NSW, Australia

Background: No vaccines are licensed for Neisseria gonorrhoeae prevention. However, a meta-analysis of observational studies reported that a meningococcal B (4CMenB) vaccine is associated with a 38% reduced risk of incident N. gonorrhoeae infection. An open-label randomised trial reported no statistically significant protection.

Methods: We conducted a multicenter, randomised, double-blind, placebo-controlled trial in men who have sex with men (MSM) aged 18–50 years. Participants were either HIV-negative and taking HIV PrEP, or living with HIV, and had a documented diagnosis of gonorrhoea or infectious syphilis within the preceding 18 months. They were randomly assigned 1:1 to receive two doses 3 months apart of 4CMenB or placebo. STI screening including N. gonorrhoeae nucleic acid amplification tests on specimens from urogenital, anorectal, and oropharyngeal sites were performed quarterly over two-years. The primary outcome was incidence of a first episode of N. gonorrhoeae infection in the per-protocol population, occurring at least four weeks after administration of the second dose. Secondary outcomes included symptomatic, asymptomatic, and site-specific infections. 

Results: During 2021-23, 654 participants were randomised, with 587 included in the primary analysis. The incidence of first episode N. gonorrhoeae was 48.1 per 100 person-years (160 events among 296 participants) in the 4CMenB group and 47.8 per 100 person-years (155 events among 291 participants) in the placebo group (incidence rate ratio 1.01, 95% confidence interval [CI] 0.80-1.26, p=0.97), for a vaccine efficacy of –0.5% (95% CI -26.16%-19.93%). The vaccine efficacy for symptomatic infection was 5.50% (95% CI -56.02%-42.82%); asymptomatic infection, -6.36% (95% CI -47.47%-23.19%); and urogenital, anorectal, and oropharyngeal infections, -20.00% (95% CI -90.24%-23.86%), -1.18% (95% CI -32.95-22.97%), and 2.58% (95% CI -27.67% to 25.65%), respectively. The incidence of serious adverse events did not differ significantly between groups.

Conclusion: 4CMenB vaccine did not reduce N. gonorrhoeae incidence among MSM at high risk of gonorrhoea.

Disclosure of Interest Statement: The GoGoVax study was funded by the National Health and Medical Research Council and GSK.