To examine evidence for 4CMenB meningococcal vaccination against gonorrhea, particularly among men who have sex with men (MSM), and whether recommendations should be reconsidered.
Approach:
Background: This editorial discusses the global burden of gonorrhea, concerns about antimicrobial resistance, and evidence that outer membrane vesicle meningococcal B vaccines may provide cross-protection against gonorrhea.
Randomized trials: The authors considered 4 randomized clinical trials of 4CMenB involving MSM at increased risk of infection. None demonstrated statistically significant protection against gonorrhea.
Observational studies: Earlier retrospective population-based studies involving adolescents and young adults reported moderate protection of approximately 30%.
Key Findings:
None of the 4 randomized trials demonstrated statistically significant efficacy of 4CMenB against gonorrhea among MSM.
Retrospective studies included general populations with absent or unknown sexually transmitted infection risk, whereas the trials enrolled MSM with known infection risks.
The relatively small trials may have lacked sufficient power to determine vaccine efficacy. Conversely, routine clinical and surveillance data in retrospective studies may have missed asymptomatic infections, particularly at extragenital sites.
Previous gonococcal infection among some trial participants might have produced immune responses that interfered with vaccine response.
Vaccination may have little effect on infection or transmission while potentially reducing symptoms, bacterial burden, or other clinical manifestations.
Vaccinated MSM might mistakenly believe they are protected against gonorrhea and reduce other precautions.
Interpretation:
Consistently nonsignificant findings from trials conducted in France, Australia, and Hong Kong suggest that MSM at high risk of gonorrhea are unlikely to benefit from 4CMenB vaccination for this indication.
Limitations:
The randomized trials were relatively small and potentially underpowered.
Differences in participants’ infection risks and infection detection may partly explain discrepancies between randomized and retrospective studies.
Trials involving women and populations at lower risk were ongoing, with results expected within a year.
Conclusion:
The authors argue that national and international scientific organizations should revisit the strategy and consider no longer recommending meningococcal B vaccination to protect MSM against gonorrhea.
