Immunogenicity After Revaccination With 23-valent Pneumococcal Polysaccharide Vaccine: Healthy Elderly People Versus Diabetic Patients

• Status: Not yet recruiting
• Trial end date: 2022-04-30

Summary

Pneumococcal disease causes thousands of infections, such as meningitis, bloodstream infections, pneumonia, and ear infections in US annually. As pneumococcal vaccines provide serotype-specific protection, it is important to induce sufficient immune responses for the most clinically relevant serotypes. All adults aged 65 years or older are recommended to receive PPSV23 vaccination irrespective of underlying medical conditions. Thus, since May 2013, South Korea introduced PPSV23 in the national immunization program for elderly individuals aged ≥65 years. Following PPSV23 vaccination, serotype-specific IgG concentrations and OPA titers increase and then decline over time thereby decreasing protective efficacy, although these might remain above pre-vaccination levels until 5 years from PPSV23 administration. The decline of pneumococcal immunity may be more prominent among chronically ill patients, including those with diabetes. Currently however, revaccination is not recommended. In this study, we aimed to evaluate the serotype specific immunogenicity between healthy elderly people and old adults with diabetes after revaccination with PPSV23 at the age of 70-75 years. Serotype-specific IgG concentrations and opsonophagocytic killing activity (OPA) titers will be assessed.

• Phase: Phase 4

Details

• Lead Sponsor: Korea University Guro Hospital
• Collaborator: Merck Sharp & Dohme Corp.
• Treatments: Heptavalent Pneumococcal Conjugate Vaccine