Immunogenicity and Safety of the Three-Dose COVID-19 Vaccine Regimen in Patients Receiving Renal Replacement Therapy: A Systematic Review and Meta-Analysis

Background: A three-dose regimen is the current standard for COVID-19 vaccination, but systematic data on immunogenicity and safety in chronic kidney disease patients remains limited. Objectives: We conducted a meta-analysis on the immunogenicity and safety of three-dose COVID-19 vaccination in patients on renal replacement therapy (RRT). Methods: Systematic literature search in four electronic databases yielded twenty eligible studies (2,117 patients, 94% of whom received mRNA vaccines) for meta-analysis. Results: The overall seropositivity rate of anti-SARS-CoV-2 was 74.2% (95% CI: 65.0-83.4%) after three-dose COVID-19 vaccination. The seropositivity rate of anti-SARS-CoV-2 in kidney transplant recipients (KTRs) was 64.6% (95% CI: 58.7-70.5%), and 43.5% (95% CI: 38.5-48.6%) of non-responders after second dose became seropositive after third dose. The seropositivity rate of anti-SARS-CoV-2 was 92.9% (95% CI: 89.5-96.2%) in dialysis patients, and 64.6% (95% CI: 46.8-82.3%) of non-responders after second dose became seropositive after third dose. In KTRs, each year increase in transplant vintage was associated with 35.6% increase in anti-SARS-CoV-2 seropositivity (95% CI: 15.9-55.4%, p = 0.01). There were no serious adverse events attributed to vaccination in KTRs, and the commonest local and systemic adverse events were injection site pain and fatigue, respectively. Conclusion: Three-dose COVID-19 vaccination regimen in patients on RRT is associated with reduced immunogenicity, especially in KTRs. There are no adverse events associated with third-dose COVID-19 vaccine in KTRs.