# Clinical outcomes in kidney transplant recipients receiving tixagevimab/cilgavimab for outpatient treatment of COVID-19: a single-center retrospective study

## TL;DR

This study shows that outpatient treatment with tixagevimab/cilgavimab reduced hospitalization and ICU needs in kidney transplant recipients with COVID-19 during the Omicron period.

## Contribution

The study provides real-world evidence of tixagevimab/cilgavimab's effectiveness in kidney transplant recipients during the Omicron wave.

## Key findings

- The tixagevimab/cilgavimab group had a lower hospitalization rate (2.9%) compared to the control group (15.5%).
- No ICU admissions occurred in the tixagevimab/cilgavimab group, versus 5.9% in the control group.
- There was no significant difference in mortality between the two groups.

## Abstract

Kidney transplant recipients (KTR) show higher morbidity and mortality from COVID-19 than the general population and have an impaired response to vaccination. Outpatient treatment with tixagevimab/cilgavimab prevented clinical deterioration in unvaccinated patients with COVID-19 during periods of Alpha and Delta dominance. Data on the clinical outcomes in KTR receiving tixagevimab/cilgavimab for outpatient treatment during Omicron dominance are scarce. We retrospectively analyzed the clinical outcomes in a single-center cohort of 102 KTR who received tixagevimab/cilgavimab for outpatient treatment of SARS-CoV-2 infection within 7 days after symptom onset between June 29, 2022, and April 4, 2023 and compared them to a historical cohort of 219 KTR, who were infected during the Omicron period, but before tixagevimab/cilgavimab treatment was employed at our institution (January 15 until June 28, 2022). The hospitalization rate and need for ICU treatment was lower in the tixagevimab/cilgavimab group compared to the control group (2.9% vs. 15.5%, p = 0.001, and 0% vs. 5.9%, p = 0.012, respectively), while there was no statistically significant difference in COVID-19 mortality between both groups (0% vs. 2.3%, p = 0.124). These real-world data further support that outpatient treatment with monoclonal antibodies such as tixagevimab/cilgavimab can prevent clinical deterioration in kidney transplant recipients during a period of Omicron dominance. Novel therapeutics are needed for variants for which tixagevimab/cilgavimab shows no neutralization.