A MENINGITIS vaccine generated bactericidal antibodies in Hajj/Umrah travelers, with solid postvaccination safety through 30 days.
Why Older Travelers Need Protection
Invasive meningococcal disease continues to carry substantial global burden, with higher case fatality rates reported in older adults. Large mass gatherings can amplify infectious disease risk, and the annual Hajj pilgrimage brings together roughly two million people each year. Because quadrivalent meningococcal vaccination is mandatory for visitors traveling to Saudi Arabia for Hajj and Umrah, clinicians advising older travelers may welcome data focused on this age group.
What This Study Tested
Investigators conducted a Phase III, open label study in Turkiye and Lebanon in healthy adults aged 56 years and older who were potential Hajj or Umrah pilgrims. Participants received a single dose of a quadrivalent meningococcal tetanus toxoid conjugate vaccine targeting serogroups A, C, Y, and W. Immunogenicity was assessed at baseline and 30 days after vaccination using serum bactericidal assays with human complement and rabbit complement. Safety outcomes were collected through 30 days after vaccination, with an additional 14-day reporting window.
Meningitis Vaccine Results After One Dose
Among 290 enrolled participants, day 30 seroprotection rates using human complement, defined as titers at or above 1:8, were 82.8% for serogroup A, 92.5% for C, 92.1% for Y, and 83.5% for W. Using rabbit complement with a threshold at or above 1:128, seroprotection rates were 83.4% for A, 90.0% for C, 94.3% for Y, and 88.9% for W. Human complement geometric mean titers at day 30 were 32 for A, 132 for C, 126 for Y, and 56.4 for W. In the per protocol analysis set, seroresponse rates ranged from 48% to 71.0% across serogroups, supporting a robust bactericidal antibody response after a single dose.
Safety Findings at 30 Days
No safety concerns were identified, and no serious adverse events related to the study vaccine were observed. Overall, the meningitis vaccine demonstrated an acceptable safety profile alongside strong immunogenicity in adults aged 56 years and older preparing for Hajj or Umrah travel.
Reference: Dbaibo GS et al. Immunogenicity and Safety of Quadrivalent Meningococcal Conjugate Vaccine (MenACYW-TT) in Potential Hajj/Umrah Pilgrims Aged ≥ 56 Years: A Phase III, Open-Label Study. Infect Dis Ther. 2026;doi:10.1007/s40121-025-01298-w.
