Meningococcal B Vaccine to Prevent <i>Neisseria gonorrhoeae</i> Infection.

Abstract

No vaccines are currently licensed for the prevention of <i>Neisseria gonorrhoeae</i> infection. Observational studies suggest that the four-component meningococcal serogroup B vaccine (4CMenB) may reduce the risk of gonorrhea. In this multicenter, double-blind, randomized, placebo-controlled trial, we assigned, in a 1:1 ratio, men who have sex with men (MSM) to receive two doses of 4CMenB or placebo. All the participants had recently received a diagnosis of <i>N. gonorrhoeae</i> infection or infectious syphilis and either tested negative for human immunodeficiency virus (HIV) and were receiving HIV preexposure prophylaxis or were living with HIV. Screening for sexually transmitted infections, including <i>N. gonorrhoeae</i> nucleic acid amplification testing of samples obtained from urogenital, anorectal, and oropharyngeal sites, was performed quarterly for 2 years. The primary outcome was a first <i>N. gonorrhoeae</i> infection after the receipt of vaccine or placebo in the per-protocol population (participants who received both 4CMenB or placebo doses, attended at least two scheduled follow-up visits after the second dose, and did not meet any exclusion criterion pertinent to the assessment of efficacy). From July 2021 through May 2023, a total of 654 participants underwent randomization, of whom 587 were included in the primary analysis. The incidence of <i>N. gonorrhoeae</i> infection was 48.1 events per 100 person-years (160 events among 296 participants) in the 4CMenB group and 47.8 events per 100 person-years (155 events among 291 participants) in the placebo group (incidence rate ratio, 1.01; 95% confidence interval [CI], 0.80 to 1.26; P = 0.97), for a vaccine efficacy of -0.5% (95% CI, -26.2 to 19.9). Vaccine efficacy was 5.5% (95% CI, -56.0 to 42.8) for symptomatic infection, -6.4% (95% CI, -47.5 to 23.2) for asymptomatic infection, and -20.0% (95% CI, -90.2 to 23.9), -1.2% (95% CI, -33.0 to 23.0), and 2.6% (95% CI, -27.7 to 25.7) for urogenital, anorectal, and oropharyngeal infection, respectively. Serious adverse events occurred in 4.7% of the participants in the 4CMenB group and in 2.8% of those in the placebo group. 4CMenB did not result in a lower incidence of <i>N. gonorrhoeae</i> infection than placebo among MSM who were at high risk for gonorrhea. (Funded by the Australian National Health and Medical Research Council and GSK; GoGoVax ClinicalTrials.gov number, NCT04415424.).