Immunogenicity and Safety of Quadrivalent Meningococcal Conjugate Vaccine (MenACYW-TT) in Potential Hajj/Umrah Pilgrims Aged ≥ 56 Years: A Phase III, Open-Label Study

Creative Commons License

Dbaibo G. S., BALIK İ., AKDEMİR İ., BUZGAN T., GÜNER H. R., Boutros C. F., ...Daha Fazla

Infectious Diseases and Therapy, cilt.15, sa.3, ss.769-785, 2026 (SCI-Expanded, Scopus) identifier identifier identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 15 Sayı: 3
  • Basım Tarihi: 2026
  • Doi Numarası: 10.1007/s40121-025-01298-w
  • Dergi Adı: Infectious Diseases and Therapy
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, EMBASE, Directory of Open Access Journals
  • Sayfa Sayıları: ss.769-785
  • Anahtar Kelimeler: Hajj/Umrah pilgrims, Immunogenicity, Invasive meningococcal disease, MenACYW-TT, Older adults, Safety, Vaccine
  • Ankara Üniversitesi Adresli: Evet

Özet

Introduction: Invasive meningococcal disease poses a substantial disease burden worldwide, including older adults (aged ≥ 56 years) along with higher case fatality rates. MenACYW-TT, a quadrivalent meningococcal tetanus toxoid-conjugate vaccine, is indicated worldwide in individuals ≥ 56 years of age and is the only licensed vaccine in the USA for this age group. The annual Hajj pilgrimage is considered an epidemiologic event with approximately two million pilgrims per year; hence, immunization with a quadrivalent meningococcal vaccine is mandatory for visitors traveling to Saudi Arabia for Umrah and Hajj. We evaluated the immunogenicity and safety of a single dose of MenACYW-TT in prospective Hajj/Umrah pilgrims aged ≥ 56 years in Turkiye and Lebanon. Methods: In this open-label phase III study (NCT03869866), conducted in Turkiye and Lebanon, healthy adults aged ≥ 56 years received a single dose of the MenACYW-TT vaccine. Serum bactericidal assays were performed using human (hSBA) and rabbit (rSBA) complements to measure antibody titers against all four serogroups at baseline (D0) and 30 days post vaccination (D30). Safety data were collected up to 30 days (+ 14 days) post vaccination. Results: A total of 290 individuals were enrolled in the study. On D30, vaccine seroprotection rates (hSBA titers ≥ 1:8) for serogroups A, C, Y, and W were 82.8%, 92.5%, 92.1%, and 83.5%, respectively, and rSBA titers (≥ 1:128) were 83.4%, 90.0%, 94.3%, and 88.9%, respectively. hSBA geometric mean titers (GMTs) were 32 [95% confidence interval (CI) 26.3–39.1], 132 (102–169), 126 (99.3–161), and 56.4 (43.8–72.6) for serogroups A, C, Y, and W, respectively. On D30, seroresponse rates in the per-protocol analysis set (PPAS) were 48–71.0%. Safety concerns and any serious adverse events related to the study vaccine were not observed. Conclusions: MenACYW-TT vaccine induced a robust immune response against all serogroups (per seroprotection rates and GMTs). A single dose of the vaccine demonstrated acceptable safety profile in potential pilgrims aged ≥ 56 years. Trial Registration: ClinicalTrials.gov, NCT03869866. A