Feasibility of C2 monitoring in Korean renal transplantation.
BACKGROUND
In spite of efforts for simplified and optimal monitoring, variability of cyclosporine (CsA) absorption has shown limited clinical impact. We performed the present study to evaluate the feasibility of C2 monitoring and the optimal target C2 level in Korean recipients.


METHODS
Sixty recipients who underwent first living donor kidney transplantations between December 2003 and May 2005 and who were treated with a regimen of CsA, mycophenolate mofetil, and steroid were enrolled in this study. CsA dose was adjusted according to conventional trough levels. Blood samples were collected just before (C0) and at 1, 2, 3, 4, 6, 8, and 12 hours (C1, C2, C3, C4, C6, C8 and C12) after dosing on days 2, 3, and 7 posttransplantation. On days 14 and 28, we determined C0, C1, C2, C3, and C4. We compared CsA levels between a no rejection versus a rejection group.


RESULTS
In 8 recipients there were 1 or more acute rejection episodes (13.3%). C2 levels correlated closely with AUC0-4 on each day (r=.892-.944, P<.01), but C2 levels were not significantly different between the no rejection and the rejection group (P>.05). Mean C2 level on days 3 to 28 was significantly different between the 2 groups. (P=.045). One recipient (5.3%) with a mean C2 level greater than 1000 ng/mL underwent acute rejection.


CONCLUSIONS
CsA concentration monitored as mean C2 levels early posttransplantation rather than a single point concentration on a single day was a predictor of acute rejection in kidney transplantation. Within the first month posttransplantation, the target C2 level is recommended to be over 1000 ng/mL for Korean recipients.
Park
J B
JB
Department of Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea.
Han
Y S
YS
Kim
S J
SJ
Choi
G S
GS
Kwon
C H D
CH
Lee
S K
SK
Kim
D J
DJ
Joh
J W
JW
D000293:Adolescent; D000328:Adult; D019540:Area Under Curve; D016572:Cyclosporine / Q000097:blood* / Q000493:pharmacokinetics / Q000627:therapeutic use*; D016903:Drug Monitoring; D005240:Feasibility Studies; D005260:Female; D006801:Humans; D007166:Immunosuppressive Agents / Q000627:therapeutic use; D016030:Kidney Transplantation / Q000276:immunology*; D007723:Korea; D008297:Male; D008657:Metabolic Clearance Rate; D008875:Middle Aged; D009173:Mycophenolic Acid / Q000031:analogs & derivatives / Q000627:therapeutic use
D007166:Immunosuppressive Agents; D016572:Cyclosporine; D009173:Mycophenolic Acid