O11.3 - Should we use the 4CMenB (Bexsero®) meningitis vaccine to protect men who have sex with men (MSM) in England against gonorrhoea? A model-based analysis of impact and cost-effectiveness.
Background: In April 2022, observational data indicated 4CMenB serogroup-B Neisseria meningitidis vaccine reduces risk of Neisseria gonorrhoeae infection by 26%(95%CI:12-37) and 40%(22-53) for 1- and 2-dose primary vaccination, respectively. We examined impact and cost-effectiveness of approaches to vaccinating higher-risk MSM in England.
Methods: We built an integrated health-economic transmission-dynamic compartmental model of gonorrhoea in MSM, with low- and high-risk activity groups (< 5/≥5 partners/year), calibrated to surveillance data for England using a Bayesian framework. We calculated vaccination costs, reductions in gonorrhoea treatment costs, and QALY (quality-adjusted life-year) gains, over 10 years (discounting 3.5%p.a), and assessed sensitivity to cost per dose. We considered two approaches to targeting higher-risk individuals – offering Vaccination-on-Diagnosis with gonorrhoea (VoD), or Vaccination-according-to-Risk (VaR): VoD plus vaccinating uninfected patients reporting ≥5 partners/year). We considered both 1- and 2-dose primary-vaccination schedules. In the base case we assumed initial protection lasts 1.5 years and a single booster-dose protects those who received 2-dose primary vaccination for a further 3 years.
Results: At the estimated UK cost of £18/dose administered (including £10/dose administration cost), vaccination is always cost-saving, irrespective of uptake. VaR is the most impactful and cost-effective, however if this is not operationally feasible to implement (because it requires enquiring about sexual behaviour) then VoD is cost-effective, but has less impact. If uptake is the same as for HPV vaccination of MSM (1st-dose: 40.8%(95%CrI:40.6-41.0), 2nd-dose (where offered): 61.7%(61.2-62.1)), then net savings for VoD(1-dose)/VoD(2-dose)/VaR(1-dose)/VaR(2-dose) are £2.3M(95%CrI:0.0-5.8)/£4.4M(0.6-9.8)/£5.8M(0.1-15.8)/£12.0M(1.9-24.6), with corresponding QALY gains 30.8(12.1-61.6)/54.4(24.1-99.9)/71.6(21.3-155.3)/133.1(46.7-261.9). At the manufacturer’s list price of £75/dose (£85/dose administered), the incremental cost-effectiveness ratio is always >£20k/QALY, therefore not cost-effective by UK criteria. Longer durations of protection increase QALY gains, and cost savings at £18/dose. However, vaccination is not cost-effective at £85/dose even if protection lasts 7.5 years after primary and booster vaccination.
Conclusion: Reassuringly for decision-makers, at UK costs targeted 4CMenB vaccination is cost-saving at any level of uptake, supporting implementation among high-risk MSM, but promoting uptake maximises benefits. The greater coverage attained by VaR and greater protection of 2-dose strategies produce greater net benefits. If other countries pay more for 4CMenB, vaccination might not be cost-saving or even cost-effective.
