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Early or Late Conversion From Tac-BD to Tac-BD in Renal Transplantation: When is the Right Time?
S J Falconer1, W R Peagam1, G C Oniscu1
1The Transplant Unit, The Royal Infirmary of Edinburgh/University of Edinburgh, Little France Crescent, Edinburgh, UK.
Background:
Increasing numbers of renal transplant recipients are converted from Prograf (Astellas Pharma, Tokyo, Japan) (tacrolimus twice daily [Tac-BD]) to Advagraf (Astellas) (tacrolimus once daily [Tac-QD]), but the optimal time for conversion is as yet unclear. This study aimed to investigate the correlation between the time of conversion from Tac-BD to Tac-QD after renal transplant and the dosing requirements, tacrolimus levels, renal function, and clinical outcomes.
Methods:
Since September 2008, 125 renal transplant patients were converted from Tac-BD to Tac-QD and followed up for 2 years after conversion. Patients were split into early (0 to 12 months) and late (>12 months) conversion groups. Demographics, Tac-QD dose, trough levels, graft function, and patient and graft outcome were prospectively collected.
Results:
Forty-four patients (35.2%) were converted early (3.82 ± 3.24 months), whereas 81 (64.8%) patients were converted late (77.35 ± 53.71 months). Tac-BD dose before conversion was higher in the early group (8.70 ± 6.34 vs 4.44 ± 2.15 mg) as was the initial Tac-QD dose (8.66 ± 6.20 vs 4.37 ± 2.04 mg, P < .0001), and remained higher for 18 months after conversion, as did the serum tacrolimus trough level levels. Renal function, acute rejection, and patient and graft survival were comparable between the groups.
Conclusions:
Patients can be safely converted to Tac-QD within the first year post-transplantation, without adverse effects on clinical outcome, despite the higher doses and tacrolimus levels for the first 18 months.
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