The Association of Tacrolimus Formulation Switching with Trough Concentration Variability: A Retrospective Cohort Study of Tacrolimus Use Post-Kidney Transplantation Based on National Drug Code (NDC) Numbers.

Journal Article

INTRODUCTION: It was hypothesized that patients experiencing at least one tacrolimus formulation switch may require more frequent therapeutic drug monitoring, subsequent dose adjustments, and a potential for untoward clinical outcomes than patients who remain on a single formulation. METHODS: Eligible patients were adult kidney transplant recipients with stable renal function at month 3 post-transplant and no evidence of acute rejection, receiving an oral, tacrolimus-based regimen. Patients were categorized into two groups (fixed or variable formulation) using the US National Drug Code (NDC) on the basis of tacrolimus formulation usage over the 12-month period. RESULTS: A total of 305 patients were enrolled from four US transplant centers; 44 (14.4%) received multiple formulations and 261 (85.6%) received a single formulation. Mean number of tacrolimus dose adjustments and mean cumulative milligram dose change were not statistically different between the two groups. Mean trough-to-dose ratio, frequency of trough level measurements, and mean number of excursions above 120% or below 80% of the patient's mean trough concentration were significantly higher in the variable compared to the fixed formulation group. CONCLUSION: A variable tacrolimus formulation regimen was associated with a higher frequency of trough level measurements and a greater number of excursions in trough levels compared with continuing on a fixed formulation regimen of tacrolimus in this retrospective chart review study. FUNDING: Astellas Pharma Global Development, Inc. Plain language summary available for this article.

Full Text

Duke Authors

Cited Authors

  • Schwartz, JJ; Lee, E; Butler, AP; Facklam, DP; Franks, B; Spalding, JR; Vassilakis, ME; Thal, GD; Irish, WD

Published Date

  • June 2019

Published In

Volume / Issue

  • 36 / 6

Start / End Page

  • 1358 - 1369

PubMed ID

  • 31004326

Pubmed Central ID

  • 31004326

Electronic International Standard Serial Number (EISSN)

  • 1865-8652

Digital Object Identifier (DOI)

  • 10.1007/s12325-019-00950-5


  • eng

Conference Location

  • United States