Improved renal function after conversion from tacrolimus/sirolimus to tacrolimus/mycophenolate mofetil in kidney transplant recipients.
BACKGROUND
There is limited data on the potential nephrotoxicity of sirolimus (SRL) and tacrolimus (TAC) in combination.


METHODS
We reviewed the course of 97 kidney transplant patients treated with SRL and reduced-dose TAC. Conversion from SRL to mycophenolate mofetil (MMF) was prescribed in a minority (n = 19) for various nonrenal side effects. We compared outcomes of converted patients to those remaining on TAC/SRL (n = 78).


RESULTS
TAC levels were increased in converters (P = 0.009). Rejection rates were similar between groups over 18 months (21% vs. 16%, p = ns). Serum creatinine (Cr) and MDRD glomerular filtration rate (GFR) were similar between groups at nadir and six-months, but at 18 months the percent change from six-month Cr was +17% in non-converters vs. -10% in converters (P = 0.004 for the difference). The difference in GFR between groups at 18 months was also significant (P = 0.01). By multivariate analysis, only conversion to MMF was associated with a greater percent change in Cr from 6 to 18 months (P = 0.015). Conversion to MMF also correlated with higher GFR at 18 months independent of rejection, delayed graft function, and ethnicity.


CONCLUSIONS
Conversion from TAC/SRL to TAC/MMF led to improved renal function despite increased TAC exposure after conversion.
Augustine
Joshua J
JJ
Division of Nephrology, University Hospitals of Cleveland, OH 44106, USA. Joshua.Augustine@uhhs.com
Chang
Peter C
PC
Knauss
Thomas C
TC
Aeder
Mark I
MI
Bodziak
Kenneth A
KA
Schulak
James A
JA
Hricik
Donald E
DE
D004359:Drug Therapy, Combination; D005260:Female; D005919:Glomerular Filtration Rate / Q000502:physiology; D006801:Humans; D007668:Kidney / Q000502:physiology*; D016030:Kidney Transplantation / Q000502:physiology; D008297:Male; D009173:Mycophenolic Acid / Q000031:analogs & derivatives* / Q000627:therapeutic use; D020123:Sirolimus / Q000627:therapeutic use*; D016559:Tacrolimus / Q000627:therapeutic use*
D009173:Mycophenolic Acid; D020123:Sirolimus; D016559:Tacrolimus