Management of nirmatrelvir/ritonavir and tacrolimus interaction in kidney transplant recipients infected by COVID-19: a three-case series

ObjectivesNirmatrelvir/ritonavir may cause a clinically relevant drug-drug interaction (DDI) with immunosuppressive drugs, such as tacrolimus, which may condition the use of this antiviral in transplant patients. We aimed to describe the management of this interaction. MethodsDescriptive study in which renal transplant patients in treatment with nirmatrelvir/ritonavir and tacrolimus were included. They suspended tacrolimus the day before starting the antiviral treatment, and the decision to restart it was made based on their tacrolimus blood levels. Main variables studied to measure this DDI were tacrolimus blood concentration, dose adjustment and serum creatinine. ResultsThree patients were included. During the study, tacrolimus levels elevation did not have repercussion in the serum creatinine, that remained stable in all patients. No patient required hospitalisation or showed signs of rejection. ConclusionsOur experience provides further evidence that this interaction should not be a contraindication to treatment with nirmatrelvir/ritonavir, and can be managed with close monitoring of tacrolimus levels.

Automated summary

This study describes the management of the drug-drug interaction between nirmatrelvir/ritonavir and tacrolimus. The results demonstrate that this interaction does not have a negative impact on renal function and transplant rejection.