title: A validated HPLC assay for the determination of R-(-)-gossypol in human plasma and its application in clinical pharmacokinetic studies.
abstract: R-(-)-gossypol acetic acid (AT-101), a natural BH3 mimetic, is investigated in a Phase I/II clinical trial for the treatment of advanced solid tumor malignancies. Gossypol undergoes rapid degradation in solution phase, which causes major technical difficulty for its quantitation in plasma. We developed and validated a sensitive HPLC assay for pharmacokinetic evaluation of gossypol. Acetonitrile deproteinization method was chosen for sample preparation and Schiff's base derivative, R-(-)-gossypol-diamino-propanol (GDP), was used as internal standard. Chromatographic separation of gossypol in plasma was performed using a Zorbax Eclipse XDB column C(18) at 30 °C. The mobile phase consists of 10 mmol/L KH(2)PO(4) (pH 3.0) and acetonitrile (20:80) at 1.0 mL/min flow rate. Linearity ranged over 56-3585 ng/mL (R(2)=0.9997±0.0003, n=4), and the limit of detection was 28 ng/mL. The intra- and inter-assay precision was less than 13.7% and the bias ranged from -7.4 to 7.0%. The method was successfully applied to characterize the pharmacokinetics of AT-101 in a Phase I clinical trial. The validated assay is accurate, and sensitive with minimum loss and rapid analysis time and suitable for quantification of gossypol for pharmacokinetics evaluation.
authors.affiliation: The Cancer Institute of New Jersey, Robert Wood Johnson Medical School, University of Medicine and Dentistry of New Jersey, 195 Little Albany Street, New Brunswick, NJ 08901, USA.
authors.forename: Hongxia
authors.initials: H
authors.lastname: Lin
authors.forename: Murugesan K
authors.initials: MK
authors.lastname: Gounder
authors.forename: Joseph R
authors.initials: JR
authors.lastname: Bertino
authors.forename: Ah-Ng Tony
authors.initials: AN
authors.lastname: Kong
authors.forename: Robert S
authors.initials: RS
authors.lastname: DiPaola
authors.forename: Mark N
authors.initials: MN
authors.lastname: Stein
mesh_terms: D000972:Antineoplastic Agents, Phytogenic / Q000493:pharmacokinetics*; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D006072:Gossypol / Q000031:analogs & derivatives* / Q000493:pharmacokinetics; D006801:Humans; D057230:Limit of Detection; D009369:Neoplasms / Q000188:drug therapy; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013997:Time Factors
chemical_list: D000972:Antineoplastic Agents, Phytogenic; D006072:Gossypol; C028178:gossypol acetic acid