Post-Marketing Surveillance Observational Study of Quadrivalent Meningococcal Diphtheria Toxoid Conjugate Vaccine (MenACWY-DT, MCV4/Menactra(®)) in the Republic of Korea, 2014–2019

BACKGROUND: Invasive meningococcal disease is a notifiable disease in the Republic of Korea. The meningococcal (groups A, C, Y, and W) polysaccharide diphtheria toxoid conjugate vaccine (MenACWY-DT, Menactra(®)) was licensed in the Republic of Korea in 2014. This post-marketing surveillance (PMS) observational study aims to assess the safety of MenACWY-DT administration of routine clinical care to individuals aged 9–23 months as a two-dose series at least 3 months apart and to individuals 2–55 years as a single dose. METHODS: The PMS observational study (NCT02864927) included participants aged 9 months to 55 years and who were given MenACWY-DT during routine healthcare visits. The study participants were followed-up for up to 30 days following vaccination (additional time was allowed for the visit or phone call to be conducted). Study outcomes included solicited and unsolicited adverse reactions, unexpected adverse events, and serious adverse events (SAEs). RESULTS: A total of 640 participants 9–23 months of age and 671 participants 2–55 years of age were eligible for safety analysis. Overall, AEs were reported by 35.3% of participants aged < 2 years and 45% of participants aged 2–55 years. Solicited adverse reactions were reported by 21.4% and 17.4% of participants aged < 2 years and 2–55 years, respectively. Unsolicited adverse reactions were reported by 26.1% and 37.9%, respectively. No vaccine-related SAEs occurred during the study. The AEs reported in Korean population were consistent with the known safety profile of MenACWY-DT, and most were of grade 1–2 in severity. CONCLUSIONS: This study did not detect any unanticipated or new safety findings of concern with MenACWY-DT in either of the study age groups, and provides reassurance that MenACWY-DT can be used as part of routine immunization care for the prevention of invasive meningococcal disease. TRIAL REGISTRATION: ClinicalTrials.gov Identifier, NCT02864927