Population pharmacokinetics of the novel anticancer agent KRN7000.
OBJECTIVE
KRN7000 is a novel anticancer agent, acting through stimulation of the immune system. The first clinical trial with this agent, which included pharmacokinetic studies, has recently been completed. The aim of the study presented here was to develop a population pharmacokinetic model for KRN7000.


METHODS
Plasma concentration-time data were gathered from 24 patients enrolled in a phase I trial in which KRN7000 was administered as a weekly slow injection at doses ranging from 50 to 4800 microg/m(2). These data were used to build a pharmacokinetic model using the nonlinear mixed-effect modeling (NONMEM) program. The model was validated by performance of 200 bootstraps.


RESULTS
A three-compartment model with interindividual variability on the central and two peripheral volumes of distribution (V1, V2 and V3) and on clearance (CL) adequately described the data. The final estimates were: V1 2.34 l, V2 2.61 l, V3 2.13 l, and CL 0.130 l/h. Of 24 covariates tested, including both demographic and pathophysiological factors, none showed a significant relationship with the pharmacokinetic parameters obtained. The bootstrap analysis provided parameter estimates within approximately 15% of the original estimates, indicating stability of the model.


CONCLUSIONS
The pharmacokinetic behavior of KRN7000 in the clinical trial could be described by a three-compartment model. Hence, KRN7000 demonstrates linear pharmacokinetics over the investigated dose range. The pharmacokinetics of KRN7000 are not influenced by patient demographic or pathophysiological characteristics.
Crul
Mirjam
M
The Netherlands Cancer Institute, Department of Medical Oncology, Plesmanlaan 121, 1066 CX Amsterdam, The Netherlands. apmcr@slz.nl
Mathôt
Ron A
RA
Giaccone
Giuseppe
G
Punt
Cornelis A
CA
Rosing
Hilde
H
Hillebrand
Michel X
MX
Ando
Yoshitaka
Y
Nishi
Nobosuke
N
Tanaka
Hideji
H
Schellens
Jan M
JM
Beijnen
Jos H
JH
D000328:Adult; D000368:Aged; D000970:Antineoplastic Agents / Q000493:pharmacokinetics*; D005260:Female; D005699:Galactosylceramides / Q000493:pharmacokinetics*; D006801:Humans; D008297:Male; D008875:Middle Aged; D008954:Models, Biological
D000970:Antineoplastic Agents; D005699:Galactosylceramides; C103873:KRN 7000