Plasma and leukemic cell pharmacokinetics of high-dose N4-behenoyl-1-beta-D-arabinofuranosylcytosine in acute leukemia patients.
The pharmacokinetics of N4-behenoyl-1-beta-D-arabinofuranosylcytosine (BHAC), a lipophilic antitumor analog of 1-beta-D-arabinofuranosylcytosine (ara-C), was investigated, by assay of plasma and leukemic cells of ten acute leukemic patients receiving 60-minute intravenous (IV) infusion of 700 mg/m2 BHAC, for BHAC and 1-beta-D-arabinofuranosylcytosine 5'-triphosphate (ara-CTP) by high-performance liquid chromatography, ara-C by radioimmunoassay, and 1-beta-D-arabinofuranosyluracil (ara-U) by gas chromatography-mass fragmentography. The plasma concentration of BHAC reached a maximum (173.4 +/- 75.3 micrograms/mL) at the end of the infusion and then declined in a biphasic pattern with an initial-phase half-life (t1/2 alpha) of 1.00 +/- .36 hours and a second-phase half-life (t1/2 beta) of 4.28 +/- 2.35 hours. That of ara-C similarly reached a maximum (102.2 +/- 39.9 mg/mL) at the end of the infusion and then declined with t1/2 alpha of 1.37 +/- 1.11 hours and t1/2 beta of 11.2 +/- 4.31 hours. Intracellular ara-CTP concentration increased in a linear-accumulation manner for the first 4 hours after the infusion, reached a maximum of .081 +/- .112 micrograms/10(7) cells at approximately 7 hours, and then declined very slowly in accordance with a one-compartment model with t1/2 of 13.56 +/- 9.62 hours.
Yoshida
T
T
Department of Internal Medicine, Toyama Prefectural Central Hospital, Japan.
Kobayashi
K
K
Okabe
Y
Y
Okumura
H
H
Matano
S
S
Kanno
M
M
Takeda
Y
Y
Ohtake
S
S
Nakamura
S
S
Matuda
T
T
D000970:Antineoplastic Agents / Q000008:administration & dosage / Q000097:blood / Q000493:pharmacokinetics*; D001086:Arabinofuranosyluracil / Q000097:blood; D002851:Chromatography, High Pressure Liquid; D003561:Cytarabine / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000097:blood / Q000493:pharmacokinetics; D006207:Half-Life; D006801:Humans; D007262:Infusions, Intravenous; D015470:Leukemia, Myeloid, Acute / Q000378:metabolism*; D054198:Precursor Cell Lymphoblastic Leukemia-Lymphoma / Q000188:drug therapy / Q000378:metabolism*
D000970:Antineoplastic Agents; D003561:Cytarabine; D001086:Arabinofuranosyluracil; C015019:enocitabine