Sirolimus appears to protect against cytomegalovirus (CMV) in organ transplant recipients. The effect of this drug in allogeneic hematopoietic stem cell transplantation recipients remains unexplored. By means of multivariate continuous-time Markov model analyses, we identified 3 independent covariates that significantly impacted the risk of CMV DNAemia: recipient/donor CMV serostatus, tacrolimus exposure, and sirolimus exposure. CMV-seropositive recipients with CMV-seronegative donors had a significantly higher probability of having detectable CMV DNAemia. Increasing the tacrolimus trough concentration from 0 to 16 ng/mL increased the probability of patients having detectable CMV DNAemia by 40% (from 40% to 80%), whereas this probability decreased by 25% (from 40% to 15%) when trough concentrations of sirolimus increased from 0 to 16 ng/mL. Sensitivity analysis showed that sirolimus exposure between 0 and 6 ng/mL has no or negligible effect on CMV DNAemia, but levels >8 ng/mL significantly decreased the number of detectable CMV DNAemia cases (the risk ratios decreased from 0.68 to 0.21 when whole blood sirolimus concentrations changed from 8 to 18 ng/mL, P < .01). In conclusion, we used a pharmacometric statistical tool to provide the first clinical evidence that fewer CMV DNAemia events become detectable as sirolimus exposure increases.
Keywords: antibiotic: antiviral; basic (laboratory) research/science; bone marrow/hematopoietic stem cell transplantation; clinical research/practice; immunosuppressant-calcineurin inhibitor: tacrolimus; immunosuppressant-mechanistic target of rapamycin: sirolimus; infection and infectious agents-viral: cytomegalovirus (CMV); infectious disease; pharmacokinetics/pharmacodynamics; pharmacology.
© 2018 The American Society of Transplantation and the American Society of Transplant Surgeons.