Tacrolimus variability and medication adherence pre‐ and post‐conversion from immediate‐release to extended‐release tacrolimus in pediatric solid organ transplant
Leandra Bitterfeld, Rachel L. Jackson, Jorge Sanchez‐Garcia, Bridget Bucher, Ashlie Brewer, Caroline HeyrendABSTRACT
Background
Adolescents receiving solid organ transplants (SOT) are at increased risk for rejection and graft loss, driven by suboptimal immunosuppressive medication adherence. This study evaluated the effect of conversion from immediate‐release tacrolimus (IR‐Tac) to extended‐release tacrolimus (LCPT) on medication adherence in pediatric SOT recipients.
Methods
We conducted a retrospective, observational single‐center study of heart, liver, and kidney transplant recipients who converted from IR‐Tac to LCPT. Medication adherence was measured as tacrolimus standard deviation (tac‐SD), with tac‐SD > 2 considered the threshold for poor adherence, and self‐reported adherence during the one year before and after conversion.
Results
Fifty‐four pediatric SOT recipients were included, with a median age of 9 years at transplant and 14.4 years at conversion from IR‐Tac to LCPT. Among the entire cohort, overall tac‐SD did not differ before and after conversion. Among children with high baseline variability (tac‐SD > 2), tac‐SD significantly decreased from a median of 3.0 to 2.7 ( p = 0.014), whereas children with low baseline variability (tac‐SD < 2) experienced a significant increase in tac‐SD from 1.3 to 2.2 ( p < 0.001). The proportion of children reporting missed doses more than once a week decreased from 13 (24%) to 7 (13%; p = 0.07). There was no change in tac‐SD between children who were and were not converted to LCPT for an adherence concern.
Conclusion
Tac‐SD decreased after conversion from IR‐Tac to LCPT among those with high baseline variability but increased among those with low baseline variability; there were no significant changes in subjective adherence measures. The effectiveness of conversion from IR‐Tac to LCPT for adherence is unclear.