ABSTRACT
INTRODUCTION: Limited published experience describes once daily, extended-release tacrolimus (LCP-Tac) use in pediatric solid organ transplantation (SOT), particularly nonrenal SOT. LCP-Tac can simplify immunosuppression (IS) regimens, minimize immediate release-tacrolimus (IR-Tac)-associated adverse effects, and promote adherence. This study describes the successful use of LCP-Tac in adolescent and young adult (AYA) SOT populations. METHODS: A single-center, retrospective chart review of AYA SOT recipients (age < 25 years) converted from IR-Tac to LCP-Tac. Graft survival, biopsy-proven acute rejection (BPAR), infection rates, estimated glomerular filtration rate (eGFR), and pill burden were assessed at five time points postconversion (1, 3, 6, 12, and 24 months). Intrapatient variability of tacrolimus, as assessed by coefficient of variability (CV%), was also analyzed. RESULTS: Twenty-nine AYA SOT recipients (19 heart, 6 kidney, and 4 liver) were converted to LCP-Tac, with a median age of 17.4 years at conversion. Conversion, mainly due to perceived or identified medication nonadherence, occurred at a median of 5.4 years posttransplant. No graft loss occurred within 24 months of conversion, and BPAR incidence rate was consistent with previous reports for these populations. Only one patient experienced CMV infection. Renal function remained stable postconversion. CONCLUSION: Successful conversion from IR-Tac to LCP-Tac was demonstrated in AYA heart, kidney, and liver transplant recipients. These AYA SOT recipients experienced reduced pill burden and improved tacrolimus trough concentration variability. However, the impact on medication adherence warrants further investigation. Future research should explore the targeted use of LCP-Tac to enhance IS tolerability and medication adherence in young SOT populations.
