(698) Covid-19 is Less Severe with the Omicron Variant Compared to Prior Variants and the Original Sars-Cov-2 Strain in Lung Transplant Recipients

PURPOSE: Multiple variants of SARS-CoV-2 have been documented throughout the COVID-19 pandemic. Mutations that lead to these variants can affect viral spread, disease severity, and the efficacy of vaccines and therapeutics. Lung transplant (LT) recipients (LTRs) are at high risk of COVID-19-related morbidity and mortality; however, disease severity may differ between SARS-CoV-2 variants. We sought to describe the clinical outcomes of LTRs with COVID-19 at different stages of the pandemic. METHODS: We performed a retrospective chart review of LTRs with COVID-19 and categorized them into 4 groups according to the prevalent variant on the date of the positive test. Chi-square and non-parametric binomial exact tests were used for comparative analyses. RESULTS: Since March 2020, 195 LTRs at our institute developed COVID-19; the median age was 66.6 years (58.7-72); 114 (58.5%) were male; 190 (97.4%) had received a bilateral LT; 106 (54.4%) had diabetes; 63 (32.3%) were obese; and 145 (74.4%) had chronic kidney disease with an eGFR <60. The most common immunosuppressive regimen included mycophenolate mofetil, tacrolimus, and prednisone (n=142; 72.8%). The median percent predicted FEV1 was 81% (IQR 63-96) and the median time from LT to COVID-19 diagnosis was 37.3 months (IQR 18.5-66.7). Rates of hospitalization, ICU admission, need for mechanical ventilation, and death were significantly lower for the Omicron variant than the original strain, the Alpha variant, and the Delta variant. However, there was no difference in length of hospital stay, development of extrapulmonary end-organ dysfunction, or persistent drop in spirometric flows (Table 1). Lastly, the utilization of vaccination and monoclonal antibodies grew over time and likely contributed to reduced COVID-19 severity in the latter part of the pandemic. CONCLUSION: COVID-19 continues to drive morbidity and mortality among LTRs; however, the severity of disease is lower with the omicron variant.