Clinical Research Directory

Inclusion Criteria: 1. Between 18 to ≤ 50 years of age 2. Men (cis and trans), trans women and non-binary people who have had sex with at least one man in the last 6 months 3. Diagnosis of gonorrhoea or infectious syphilis in the last 18 months 4. Committed not to take doxycycline as prophylaxis for the duration of the trial 5. Able to understand spoken and written English 6. Willing and likely to comply with the trial procedures for 2 years 7. Agree to be contacted via short message service (SMS)/phone/ email by the study team AND EITHER 1. HIV-negative (with an HIV negative antibody test within 4 months of screening) and taking HIV PrEP (daily PrEP or on-demand PrEP) within the last 4 months at the time of enrolment or 2. HIV-positive and on an antiviral regimen, with an undetectable virus level of \<200 copies/ml and a CD4 count \>350 cells/cmm (to optimise the immune response to vaccine) within 12 months of screening Exclusion Criteria: 1. Have a previous history of vaccination for meningococcal B with 4CMenB 2. Have contraindications to receiving the meningococcal B vaccine which include: * Anaphylaxis following a previous dose of any meningococcal vaccine * Anaphylaxis following any vaccine component 3. Are participating in biomedical prevention strategies for bacterial STIs (participation in diagnostic or treatment studies is not an exclusion) 4. Are taking long-term (\> 4 weeks) antibiotic for prophylaxis or treatment for acne, malaria, syphilis or other bacterial condition(s) 5. Have defects in, or deficiency of, complement components, including factor H, factor D or properdin deficiency 6. Are taking or will receive complement inhibitors such as eculizumab (a monoclonal antibody directed against complement component C5) or ravulizumab 7. Have functional or anatomical asplenia, including sickle cell disease or other haemoglobinopathies, and congenital or acquired asplenia 8. Have had a haematopoietic stem cell transplant 9. Have any major unstable medical condition or therapy that may cause immune compromise (e.g. chemotherapy, radiation, corticosteroids \[prednisone \>5mg/day\] within 14 days prior to screening) 10. Documented allergy to latex and/or kanamycin 11. Have prior known meningococcal disease 12. Positive pregnancy test at screening