Humoral and cellular immunogenicity of a fourth dose BNT162b2 in children with chronic kidney diseases

Area of Science:

• Pediatric Nephrology
• Immunology
• Infectious Diseases

Background:

• Children with chronic kidney disease (CKD) face heightened risks from severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections.
• Vaccine boosters are recommended for children with CKD, yet data on a fourth dose's efficacy in this group is scarce.

Purpose of the Study:

• To evaluate the immunogenicity and safety of a fourth dose of the BNT162b2 (Pfizer-BioNTech) COVID-19 vaccine in pediatric patients with CKD.
• To assess both humoral and cellular immune responses following the booster vaccination.

Main Methods:

• A prospective study involving 21 children with CKD, aged 5-18 years.
• Administration of a fourth BNT162b2 dose (0.1 mL for 5-11 years, 0.3 mL for 11-18 years).
• Assessment of antibody levels and T-cell responses at baseline, and 1 and 6 months post-vaccination.

Main Results:

• The fourth BNT162b2 dose significantly increased antibody and T-cell responses in children with CKD.
• Kidney transplant recipients and those on calcineurin inhibitors showed lower antibody levels at 1 month post-dose.
• Three breakthrough infections occurred, with one hospitalization; one child experienced transient gross hematuria. Safety was acceptable.

Conclusions:

• A fourth dose of the BNT162b2 vaccine is immunogenic and safe for children with chronic kidney disease.
• The findings support the use of COVID-19 vaccine boosters in this high-risk pediatric population.