Effectiveness and Durability of COVID-19 Vaccination in 9447 Patients with IBD: A Systematic Review and Meta-Analysis.

BACKGROUND: The serological responses after SARS-CoV-2 vaccination may be attenuated in immunocompromised individuals. AIMS: To systematically evaluate the seroconversion rates after complete COVID-19 vaccination in patients with inflammatory bowel disease (IBD). METHODS: Electronic databases were searched to identify studies reporting response to COVID-19 vaccination in IBD. Pooled seroconversion rates after complete vaccination were calculated. Subgroup analysis for vaccine types was also performed. Pooled seroconversion rates for various drugs/classes were also estimated. The pooled rates of breakthrough infections in vaccinated IBD patients were estimated. The pooled neutralization rates after complete vaccination were also estimated. The studies reporting durability of titers were systematically assessed. RESULTS: A total of 46 studies were included. The pooled seroconversion rate for complete vaccination (31 studies, 9447 patients) was 0.96 (95%CI, 0.94-0.97, I2=90%). When compared to healthy controls, the pooled relative risk of seroconversion was lower (0.98; 0.98-0.99, I2=39%). The pooled seroconversion rates were statistically similar among various drug classes. The pooled positivity of neutralization assays (8 studies, 771 participants) was 0.80 (95%CI, 0.70-0.87, I2=82%). The pooled relative risk of breakthrough infections in vaccinated IBD patients was similar to vaccinated controls (0.60, 95%CI, 0.25-1.42, I2=79%). Most studies suggested that titers fall after 4 weeks of COVID-19 vaccination and the decay was higher in patients on anti-TNF alone or combination with immunomodulators. An additional dose of COVID-19 vaccine elicited serological response in most non-responders to complete vaccination. CONCLUSION: Complete COVID-19 vaccination is associated with seroconversion in most patients with IBD. The decay in titers over time necessitates consideration of additional doses in these patients.