Mycophenolic Acid reaches therapeutic levels whereas mycophenolate mofetil does not.
BACKGROUND
In kidney transplanted children, it is difficult to obtain blood levels of mycophenolic acid between 2 and 4 microg/mL, when mycophenolate mofetil doses up to 30 mg/kg/d are given two or three times a day. We proposed that using mycophenolic acid, instead of the salt mycophenolate mofetil, may help us to reach target levels.


OBJECTIVE
We sought to describe the pharmacokinetics of mycophenolic acid in eight kidney transplanted children over a period of 1.2 +/- 0.8 years.


METHODS
Eight patients (5 boys and 3 girls) aged 7.0 +/- 1.8 years received cadaveric kidney transplantations. Induction with basiliximab was followed by cyclosporine (n = 4) or tacrolimus (n = 4), tapered steroids (withdrawal at 12 months in six cases and maintained at 0.15 mg/kg/d in two cases), and mycophenolate mofetil (25 to 30 mg/kg/d two or three times a day). For 1.0 +/- 0.3 years mycophenolic acid levels were between 0.8 +/- 0.3 microg/mL. When mycophenolic acid sodium tablets were available, all patients were switched to this drug.


RESULTS
After the conversion, blood levels obtained at 8 +/- 3 days were 1.5 to 5.0 microg/mL (median, 3.2), which were far closer to the target 2 to 4 microg/mL. No gastrointestinal disorders were observed with the follow-up of 72 +/- 18 days.


CONCLUSIONS
Mycophenolic acid sodium reaches therapeutic levels whereas mycophenolate mofetil does not. If mycophenolic acid were available in syrup form, it could be used in patients under 5 years of age. It is necessary to follow these patients to rule out enzymatic induction.
Vilalta Casas
R
R
Pediatric Nephrology Department, Vall d'Hebron Hospital, Barcelona, Spain. rvilalta@vhebron.net
Vila López
A
A
Nieto Rey
J L
JL
Lara Moctezuma
L E
LE
Madrid Aris
A
A
Quintana Montero
M
M
Pou Clave
L
L
D002648:Child; D004305:Dose-Response Relationship, Drug; D005260:Female; D006801:Humans; D016030:Kidney Transplantation / Q000276:immunology*; D008297:Male; D009173:Mycophenolic Acid / Q000031:analogs & derivatives* / Q000493:pharmacokinetics* / Q000627:therapeutic use*; D012086:Reoperation; D013329:Structure-Activity Relationship
D009173:Mycophenolic Acid