title: Measurement of the novel antitumor agent 17-(allylamino)-17-demethoxygeldanamycin in human plasma by high-performance liquid chromatography.
abstract: A sensitive HPLC assay has been developed to determine the concentration of 17-(allylamino)-17-demethoxygeldanamycin (AAG) in human plasma over the concentration range of 12.5 to 2,500 nM (7.33 to 1,465 ng/mL). After the addition of 1,000 nM geldanamycin as the internal standard, 1 mL samples of human plasma were subjected to solid-phase extraction, via Bond-Elut C18 cartridges, followed by analysis using an isocratic reversed-phase HPLC assay with UV detection. A Phenomenex Kingsorb, 3 micron, C18, 150x4.60 mm column and a Phenomenex Security Guard pre-column, C18 (ODS, Octadecyl), were used to achieve separation. AAG and GM were monitored at 334 and 308 nm, respectively, on a Hewlett-Packard 1050 Diode-Array Detector. The mobile phase, run at a flow-rate of 1 mL/min, was composed of 50% (v/v) 25 mM sodium phosphate (pH 3.00) with 10 mM triethylamine and 50% acetonitrile. HPLC effectively resolved AAG with retention times of 14.60 +/- 0.54 min and the internal standard geldanamycin at 10.72+/-0.38 min (n = 15). This assay was able to measure plasma concentrations of AAG, the lower limit of quantitation being 12.5 nM, at a starting dose of 10 mg/m2 infused intravenously over 1 h in a Phase I clinical trial in adult patients with solid tumors.
authors.affiliation: Developmental Therapeutics Department, Medicine Branch, Division of Clinical Sciences, National Cancer Institute, Bethesda, MD 20889, USA.
authors.forename: E B
authors.initials: EB
authors.lastname: Agnew
authors.forename: R H
authors.initials: RH
authors.lastname: Wilson
authors.forename: J L
authors.initials: JL
authors.lastname: Grem
authors.forename: L
authors.initials: L
authors.lastname: Neckers
authors.forename: D
authors.initials: D
authors.lastname: Bi
authors.forename: C H
authors.initials: CH
authors.lastname: Takimoto
mesh_terms: D000903:Antibiotics, Antineoplastic / Q000097:blood* / Q000627:therapeutic use; D016227:Benzoquinones; D002851:Chromatography, High Pressure Liquid / Q000379:methods* / Q000592:standards; D017321:Clinical Trials, Phase I as Topic; D004355:Drug Stability; D006801:Humans; D047029:Lactams, Macrocyclic; D015394:Molecular Structure; D011809:Quinones / Q000737:chemistry / Q000592:standards; D012015:Reference Standards; D017828:Rifabutin / Q000031:analogs & derivatives / Q000097:blood* / Q000737:chemistry / Q000627:therapeutic use
chemical_list: D000903:Antibiotics, Antineoplastic; D016227:Benzoquinones; D047029:Lactams, Macrocyclic; D011809:Quinones; D017828:Rifabutin; C112765:tanespimycin; C001277:geldanamycin