Humoral and cellular response of COVID-19 vaccine among solid organ transplant recipients: A systematic review and meta-analysis

Abstract

Background: We aimed to analyze the humoral and cellular response to standard and booster (additional doses) COVID-19 vaccination in solid organ transplantation (SOT) and the risk factors involved for an impaired response. Methods: We did a systematic review and meta-analysis of studies published up until January 11, 2022, that reported immunogenicity of COVID-19 vaccine among SOT. The study is registered with PROSPERO, number CRD42022300547. Results: Of the 1527 studies, 112 studies, which involved 15391 SOT and 2844 healthy controls, were included. SOT showed a low humoral response (effect size [ES]: 0.44 [0.40–0.48]) in overall and in control studies (log-Odds-ratio [OR]: −4.46 [−8.10 to −2.35]). The humoral response was highest in liver (ES: 0.67 [0.61–0.74]) followed by heart (ES: 0.45 [0.32–0.59]), kidney (ES: 0.40 [0.36–0.45]), kidney-pancreas (ES: 0.33 [0.13–0.53]), and lung (0.27 [0.17–0.37]). The meta-analysis for standard and booster dose (ES: 0.43 [0.39–0.47] vs. 0.51 [0.43–0.54]) showed a marginal increase of 18% efficacy. SOT with prior infection had higher response (ES: 0.94 [0.92–0.96] vs. ES: 0.40 [0.39–0.41]; p-value