Monoclonal Antibody Therapy in Kidney Transplant Recipients With Delta and Omicron Variants of SARS-CoV-2: A Single-Center Case Series.

Neutralizing monoclonal antibody treatments have shown promising preliminary results in kidney transplant recipients infected with SARS-CoV-2. However, their efficacy in kidney transplant recipients infected with Omicron variant has not been reported yet. Single-center retrospective study. We included all consecutive kidney transplant recipients treated with monoclonal antibodies for SARS-CoV-2 infection (positive polymerase chain reaction on nasopharyngeal swab) between June 10 2021 and January 14 2022. Forty-seven kidney transplant recipients were included. All patients had symptoms evolving for ≤ 7 days and no oxygen therapy need at monoclonal antibody infusion. Symptoms at diagnosis were mainly cough (n=25 [53%]) and fever (n=15 [32%]). Eighty-three percent of the cohort (n=39) had been vaccinated with at least 2 doses before infection, of whom 77% (n=30) had demonstrated a vaccine-induced humoral response. They were treated with either casirivimab-imdevimab (n= 16 [34%]) or sotrovimab (n= 31 [66%]) a median of 2 (ranges 0-6) days after the onset of symptoms. Except for one mild allergic reaction during casirivimab-imdevimab infusion, no side effects were reported. Median viral loads at admission (day 0) and 7 days after mAb infusion were 2,110,027 (ranges 1000-153,798,962) copies/mL and 1,000 (ranges 0-10,000,000) copies/mL, respectively. Genotypes were available for 22 kidney transplant recipients (47%). Omicron, Delta, and Gamma variants were identified in 13 (59%), 8 (36%), 1 (5%) patients, respectively. In kidney transplant recipients infected with Omicron variant, the median viral loads at day 0 and day 7 were 752,789 (ranges 4000-12,859,300) copies/mL and 1,353 (ranges 0-1,211,163) copies/mL, respectively. Two kidney transplant recipients required hospitalization immediately after sotrovimab perfusion for oxygen therapy that was weaned in 3 days allowing patients' discharge. None were admitted to the intensive care unit or died. Small sample-size, no control group. Neutralizing monoclonal antibody therapy is associated with positive outcomes in kidney transplant recipients with mild COVID-19, including those infected with the Omicron variant