Suitable whole blood levels 2 hours after neoral in liver transplant patients: experiences at a single center.
Whole blood levels 2 hours after Neoral (C2) administration were observed to correlate better with area under the curve (AUC(0-4)) than trough levels (C0), suggesting that C2 may be the best single time point predictor of Neoral absorption. Owing to concerns about drug toxicity due to excessive immunosuppression, C2 adjustments to target blood levels may represent an advance. The present study measured C2 and levels to determine which correlated more closely with AUC(0-4).


METHODS
Between August 2003 and July 2004, 40 adult liver transplantations were performed in our center. All patients received Neoral twice daily. They were maintained at a C0 level of about 200 ng/mL. C0 levels were measured daily. C2 levels were estimated on postoperative days 3, 5, 7, 14, and 28. AUC(0-4) performed on postoperative days 3, 7, and 28 was calculated using the trapezoidal rule.


RESULTS
The mean AUC(0-4), C0, C1, C2, C3, and C4 were 1100.3 +/- 484.8 ng/mL, 197.1 +/- 84.7 ng/mL, 240.7 +/- 166.2 ng/mL, 307.8 +/- 162.6 ng/mL, 302.8 +/- 138.9 ng/mL, and 300.3 +/- 142.8 ng/mL, respectively. C2 correlated with AUC(0-4) (R2 = 0.868: P < .05) better than C0 (R2 = 0.245: P < .05), C1 (R2 = 0.604: P < .05), or C4 (R2 = 0.583: P < .05).


CONCLUSIONS
Neoral dose monitoring according to a mean C2 range of 307.8 +/- 162.6 ng/mL correlated better with AUC(0-4). Further studies are required to determine suitable C2 levels in liver transplant patients.
Kim
K H
KH
Division of HBP Surgery and Liver Transplantation, Department of Surgery, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea. khkim620@amc.seoul.kr
Lee
S G
SG
Lee
Y J
YJ
Park
K M
KM
Hwang
S
S
Ahn
C S
CS
Moon
D B
DB
Ha
T Y
TY
Song
K W
KW
Kim
D S
DS
Jung
D H
DH
Kim
B S
BS
Moon
K M
KM
Lee
H J
HJ
Park
J I
JI
Ryu
J H
JH
D000328:Adult; D019540:Area Under Curve; D016572:Cyclosporine / Q000097:blood* / Q000627:therapeutic use*; D016903:Drug Monitoring / Q000379:methods; D006801:Humans; D007166:Immunosuppressive Agents / Q000097:blood / Q000627:therapeutic use; D008111:Liver Function Tests; D016031:Liver Transplantation / Q000276:immunology / Q000502:physiology*; D012044:Regression Analysis; D012189:Retrospective Studies
D007166:Immunosuppressive Agents; D016572:Cyclosporine