Comparing the Effect of Immediate versus Delayed Initiation of Tacrolimus on Delayed Graft Function in Kidney Transplant Recipients: A Randomized Open-label Clinical Trial

Objective: Delayed graft function (DGF) is an early complication after kidney transplantation with negative impact on allograft outcomes. This study assessed the effect of delayed initiation of tacrolimus as a nephrotoxic drug, on DGF occurrence and allograft function. Methods: This randomized, open-label clinical trial was conducted on kidney transplant recipients with the age of at least 14 years who underwent the first kidney transplantation from deceased or living donor. Patients were randomly allocated to immediate (n = 26) or delayed tacrolimus (n = 27) groups. All patients received thymoglobulin as induction therapy and similar maintenance immunosuppression including tacrolimus, mycophenolate, and prednisolone with the difference in the time of initiation of tacrolimus either on the day of transplantation (immediate tacrolimus group) or day 3 after transplant (delayed tacrolimus group). Findings: DGF incidence (46.15% vs. 37.04%; P = 0.501) and duration (9.75 +/- 6.41 vs. 8.6 +/- 6.16 days; P = 0.675) were not different between the immediate and delayed tacrolimus groups. Estimated creatinine clearance using Cockcroft-Gault equation (63.14 +/- 18.81 vs. 58.19 +/- 19.42 mL/min in immediate and delayed tacrolimus groups respectively; P = 0.373) and estimated acute rejection-free survival were also comparable between the groups over the 3 months of follow-up. Compared with the immediate group, the delayed tacrolimus group showed higher estimated 3-month grafts' survival (100% vs. 84.27%; P = 0.072). Conclusion: Delayed initiation of tacrolimus after kidney transplantation under the umbrella of thymoglobulin induction did not result in either lower incidence or duration of DGF or improved the level of graft function in kidney transplant recipients but non-statistically significant increased 3-month grafts' survival.