Short ArticleEvaluating the conversion to extended-release tacrolimus from immediate-release tacrolimus in liver transplant recipientsChoi, Davida,,b; Thaker, Sarangb; West-Thielke, Patriciac; Elmasri, Annestia; Chan, ChristineaAuthor Information aUniversity of Illinois at Chicago College of Pharmacy bDepartment of Medicine, Division of Gastroenterology and Hepatology cDepartment of Surgery, Division of Transplant, University of Illinois at Chicago, Chicago, Illinois, USA Received 8 February 2021 Accepted 10 March 2021 Correspondence to David Choi, PharmD, University of Illinois at Chicago College of Pharmacy, 833 S Wood Street, Suite 164, M/C 886, Chicago, IL 60612, USA, Tel: +312 355 3113; fax: +575 205 0310; e-mail: [email protected] European Journal of Gastroenterology & Hepatology: August 2021 - Volume 33 - Issue 8 - p 1124-1128 doi: 10.1097/MEG.0000000000002172 Buy Metrics Abstract Background A new formulation of once daily extended-release tacrolimus (LCP-tac, Envarsus XR) was approved for use in the USA for kidney transplant recipients in 2015. There are limited data regarding real-world observations with conversion to LCP-tac in liver transplant recipients. Methods We performed a retrospective analysis of liver transplant recipients treated with LCP-tac. Data collection included (1) reasons for switching to LCP-tac; (2) conversion ratio used; (3) kidney function at time of conversion and 3 months after; (4) outcomes of conversion [acute cellular rejection rates and cytomegalovirus (CMV) viremia] within 3 months of conversion. Results Average conversion ratio used to achieve therapeutic drug level without further dose adjustment was 1:0.73 (SD 0.11). Median time after transplant was 508 days (IQR 736). Common reasons patients were switched to LCP-tac were from fluctuations in tacrolimus levels (44%) and adverse effect of tremor (32%). Among patients who were switched due to tremors 88% noted significant improvement. There was no difference in serum creatinine (P = 0.55) or glomerular filtration rate (P = 0.64) from baseline to 3 months postconversion. There were no episodes of acute cellular rejections or CMV viremia postconversion. Conclusion This observational study demonstrated that conversion of immediate-release tacrolimus to LCP-tac in liver transplant recipients was well tolerated and effective. Copyright © 2021 Wolters Kluwer Health, Inc. All rights reserved.