Seroconversion rate after primary vaccination with two doses of BNT162b2 versus mRNA-1273 in solid organ transplant recipients: a systematic review and meta-analysis

Abstract

Background.Inthegeneralpopulation,theseroconversion rateafterprimaryvaccinationwithtwodosesofanantisevereacuterespiratorysyndromecoronavirus2messenger RNA(mRNA)vaccinereachesnearly100%,withsignificantly higherantibodytitersaftermRNA-1273vaccinationcompared toBNT162b2vaccination.Hereweperformedasystematic reviewandmeta-analysistocomparetheantibodyresponse aftertwo-dosemRNA-1273versusBNT162b2vaccinationin solidorgantransplant(SOT)recipients. Methods.Asystematicliteraturereviewwasperformedusing PubMed,WebofScienceandtheCochraneLibraryand originalresearchpaperswereincludedforameta-analysisto calculatevaccine-specificseroconversionratesforeachofthe mRNAvaccines.Next,thepooledrelativeseroconversionrate wasestimated. Results.Eightstudiesthatdescribedthedevelopmentofantibodiesagainstreceptor-bindingdomain(RBD)and/orspike proteinwereeligibleformeta-analysis.Twoofthesestudies alsoreportedantibodytiters.Themeta-analysisrevealedlower seroconversionratesinSOTrecipientsvaccinatedwithtwo dosesofBNT162b2{44.3%[95%confidenceinterval(CI) 34.1–54.7]}ascomparedwithpatientsvaccinatedwithtwo dosesofmRNA-1273[58.4%(95%CI47.2–69.2)].Therelative seroconversionratewas0.795(95%CI0.732–0.864). Conclusions.Thissystematicreviewandmeta-analysis indicatesthatinSOTrecipients,higherseroconversionrates wereobservedaftervaccinationwithmRNA-1273compared withBNT162b2.