Post-licensure observational safety study after meningococcal B vaccine 4CMenB (Bexsero) vaccination within the...

The study investigated the safety of 4-component meningococcal serogroup B vaccination (4CMenB) in routine care. 4CMenB exposure and seizures, febrile seizures and Kawasaki disease were identified from The Health Improvement Network (THIN) database of UK electronic primary healthcare records, 2015-2018. A self-controlled case series analysis was completed. Anaphylaxis, Guillain-Barré syndrome and acute disseminated encephalomyelitis were secondary outcomes. A total of 107,231 children aged 1-18 months received ≥1 doses of 4CMenB vaccination. Most 4CMenB exposure (93%) was on the same day as other vaccines within a complete national immunisation program stage. With day 0 as day of vaccination, 43 seizures occurred in days 0-6 after 239,505 doses, and 23 febrile seizures occurred in days 0-6, and 4 Kawasaki disease cases in days 1-28 after 194,929 4CMenB doses. Adjusted incidence rate ratios including all 4CMenB exposures were 1.43 (95%CI: 1.02-2.02) for seizures and 1.72 (95%CI: 1.08-2.75) for febrile seizures. There were insufficient cases to model Kawasaki disease, and no cases of the secondary outcomes in risk periods when they may be associated with the vaccination. This study shows few cases of the outcomes after vaccination including 4CMenB with an increased risk of seizures and febrile seizures. It is not possible to attribute the finding to one specific vaccination as the majority of 4CMenB was given with other vaccinations. Trial registration: NA.