Converting immunosuppression from an oral suspension to a granule formulation of tacrolimus in pediatric renal transplant recipients.

OS of tacrolimus prepared from tacrolimus powder is not licensed for children. A licensed GF for OS allows flexibility for body weight-based dose adjustments. This study aimed at exploring the efficacy of conversion from OS to the GF of tacrolimus in stable pediatric renal transplant recipients. Records of 25 pediatric renal transplant recipients aged under 18 years who were switched from an unlicensed tacrolimus OS to GF were reviewed. At day 0, 1 week, and 4-8 weeks post-conversion, there were no differences regarding daily tacrolimus dose (3.4 ± 3 vs 3.5 ± 2.9 vs 3.5 ± 2.9 mg/day), trough tacrolimus levels (4.5 ± 2.7 vs 4.2 ± 2.7 vs 4.4 ± 3.1 ng/mL), dose-normalized trough tacrolimus levels (1.7 ± 1.1 vs 1.5 ± 1.0 vs 1.7 ± 1.3 ng/mL/mg), PCr (65.6 ± 29.4 vs 67.9 ± 30.4 vs 69.8 ± 27.9 μmol/L), and eGFR (73 ± 24.9 vs 68.7 ± 20.2 vs 65.5 ± 18.2 mL/min/1.73 m2 ) (P > .05). GF dose adjustment was required in 52% of participants. Eighty-eight percent of patients had to return for repeat tacrolimus levels following dose modifications, generating 33 extra visits (≥2 extra visits for 1/3 of subjects). No rejection episodes occurred in the year after conversion. In conclusion, conversion from tacrolimus OS to GF in stable pediatric renal transplant recipients is safe and efficacious. However, close therapeutic drug monitoring in the immediate post-conversion period is necessary.