Interleukin-2 Profiles Shortly After Tacrolimus Conversion From a Twice-Daily to Once-Daily Regimen

Performance of modified-release tacrolimus after conversion in liver transplant patients indicates potentially favorable outcomes in selected cohorts

Clinical outcomes, dose changes, and dose-equalized tacrolimus concentrations were examined sequentially in 129 liver transplantation (LT) recipients after successful conversion to once daily modified-release tacrolimus either early (within 1 month) or late (>1 month) after LT. The data were compared with data for a group of 60 patients maintained on twice daily conventional-release tacrolimus. Formulation- and time-dependent changes in dose requirements for once and twice daily tacrolimus differed after transplantation. A 1.7-fold initial increase in the median daily dose was required to achieve target tacrolimus concentrations in the early-conversion cohort (P = 0.006), whereas a 1.25-fold increase was required for those converted later (P = 0.013 and P < 0.001 for the difference). In the subsequent 2 months, the median daily dose fell by 20% in the early-conversion cohort, remained stable for the late-conversion cohort, but rose by 33% with conventional therapy. Lower median dose-equalized concentrations persisted for up to 3 months after the conversion to modified-release therapy. Sex, ethnicity, and the underlying liver disease did not significantly affect these variables. The frequency of treated biopsy-proven acute rejection episodes fell approximately 4-fold after the conversion to modified-release tacrolimus, most notably in the late-conversion cohort, which experienced a high incidence of rejection before conversion. Posttransplant increases in serum creatinine concentrations were smaller after the introduction of modified-release tacrolimus in the late-conversion group (0.7 versus 4 mg/mL for twice daily tacrolimus over 6 months). Reduced interpatient variability in tacrolimus concentrations was evident in the early-conversion cohort versus the twice daily cohort. A decline in intrapatient variability accompanied the reduction in acute rejection in the late-conversion cohort. Our data highlight potential benefits for the rejection rate and renal function on conversion to once daily modified-release tacrolimus late after LT.

Long-term interleukin-2 assessment after conversion from a twice-daily to once-daily tacrolimus regimen in stable kidney recipients

Conversion to tacrolimus (Tac) to once daily (Tac-O) formulation is commonly followed by a 20% reduction in Tac trough levels in the first month. It is not associated with modifications of renal function but there is the issue of its effects on inflammatory cytokines and on subclinical rejection. The aim of our study was to evaluate long-term interleukins (IL)-2 profiles in stable renal transplant patients after Tac-O conversion. We enrolled 10 stable kidney transplant patients converted to Tac-O. Tac trough levels, serum creatinine concentrations, glomerular filtration rate using the Modification of Diet in Renal Disease formula, C-reactive protein, IL-2 levels, and clinical assessments were performed monthly for 6 months before and 12 months after conversion. Despite the significant reduction in Tac trough levels, we did not observe alterations suggestive of clinical or subclinical acute rejection.