Safety and efficacy of nirmatrelvir and ritonavir in kidney transplant recipients with COVID-19.

Kidney transplant recipients (KTRs) are at an elevated risks for severe COVID-19 due to immunosuppression and comorbidities. This study retrospectively evaluated the safety and efficacy of nirmatrelvir-ritonavir (NR) in 42 KTRs with COVID-19, adjusting dosages based on estimated glomerular filtration rates. Over a 1-year follow-up, renal and hepatic functions, inflammatory markers, and acute respiratory distress syndrome (ARDS) incidence were monitored. Within the studied cohort, oxygen therapy was required in 64% of patients, with 19% necessitating mechanical ventilation; 21% developed ARDS. Multivariate analysis identified higher albumin levels (odds ratio (OR) = 0.696, 95% confidence interval (CI) 0.515 - 0.940) and CD4+ T-cell counts (OR = 0.982, 95% CI 0.968 - 0.998) as protective against ARDS, with an AUC of 0.859. Significant reductions in serum creatinine (p < 0.001) and aspartate aminotransferase (p = 0.01) were observed from admission to discharge, while alanine aminotransferase and estimated glomerular filtration rate (eGFR) remained stable. Complications were rare, occurring in only 2 patients. NR therapy demonstrated safety and effectiveness in KTRs, evidenced by improvements in renal and hepatic function as well as stable graft outcomes. CD4+ T-cell counts and albumin levels were identified as potential predictors of ARDS. These findings underscore the significance of early antiviral intervention and meticulous optimization of immunosuppressive management. However, further validation through larger multicenter prospective studies is necessary.