Improved LCP Tacrolimus XR Dosing and Monitoring Outcomes With a Genotype-Based Dosing Algorithm Versus Weight Based Dosing.

The aim of this study was to assess the impact of CYP3A5 genotype-based tacrolimus (tac) XR versus weight-based dosing among adult kidney transplant recipients. This was a retrospective longitudinal matched cohort analysis. From February 2021 to June 2023, tac XR was dosed using standard weight-based dosing. Starting in June 2023, genotype-based dosing was used; 148 patients were included (74 in each arm). Baseline characteristics were well balanced between the groups, except for age (control 46 ± 14 vs. 52 ± 14 years, p < 0.01); 32% were females, 36% were African American, 84% were living donors, 40% had DM, and 10% had DGF. At 90-days post-txp, the genotype guided cohort had an average of two fewer tacrolimus dose adjustments per patients (4 vs. 6, p < 0.0001), spent longer time in therapeutic range (59% vs. 47%, p = 0.004), and less time in concerning range (9% vs. 18%, p < 0.0001). Acute rejection, de novo donor specific antibodies, and eGFR was similar between the two cohorts. This matched cohort analysis assessing a genotype-based dosing algorithm demonstrated improved tac XR dosing efficiency. Patients on average, needed two fewer dose adjustments, spent longer time in therapeutic range and had significantly less time in concerning range.