Tixagevimab/cilgavimab for the prevention of COVID-19 in solid organ transplant recipients

Tixagevimab/cilgavimab (tix/cil) received emergency use authorization in December 2021 for pre-exposure prophylaxis against COVID-19 in moderately to severely immunocompromised patients. Our study aimed to describe the incidence of COVID-19 infection and assess the immunologic risks associated with tix/cil in kidney, pancreas, liver, and heart transplant recipients. Retrospective chart review was completed to provide descriptive analysis. Outcomes data included COVID-19 infection, severity of COVID-19 infection, graft function, and rejection. Safety outcomes included cardiovascular (CV) and hypersensitivity events post tix/cil administration. A total of 410 transplant patients were included in the analysis: 20 heart, 92 liver, 243 kidney, 25 simultaneous pancreas/kidney, 23 simultaneous liver/kidney, and seven simultaneous heart/kidney. Twenty-seven (6.5%) patients tested positive for COVID-19 via PCR or antigen test post tix/cil. No apparent difference was observed in patients testing positive for COVID-19 by type of organ transplant (p = .122). Twenty-five of the 27 patients testing positive for COVID-19 reported symptomatic infection, only nine of whom were hospitalized. No patients were mechanically ventilated and no deaths due to COVID-19 occurred. No significant changes in graft function were observed. Clinically significant rejection was diagnosed and treated in four patients. COVID-19 breakthrough infection rates remained low in immunocompromised solid organ transplant recipients who received tix/cil. No significant immunologic risks were observed.