A simple, sensitive and reliable LC-MS/MS method for the determination of 7-bromo-5-chloroquinolin-8-ol (CLBQ14), a potent and selective inhibitor of methionine aminopeptidases: Application to pharmacokinetic studies

Abstract

CLBQ14 is an 8-hydroxyquinoline analogue that inhibits methionine aminopeptidase (MetAP), an enzyme responsible for the post-translational modification of several proteins and polypeptides. MetAP has been validated as druggable target for some infectious diseases, and its inhibitors have been investigated as potential therapeutic agents. In this study, we developed and validated a liquid chromatography tandem-mass spectrometry (LC-MS/MS) method for the quantification of CLBQ14 in solution, and in rat plasma and urine. This method was applied to the pharmacokinetic evaluation of CLBQ14 in adult male Sprague Dawley (SD) rats. Chromatographic separation was achieved using an ultra-high-performance liquid chromatography (UHPLC) system equipped with Waters XTerra MS C18 column (3.5 μm, 125Å, 2.1 × 50 mm) using 0.1% formic acid in acetonitrile/water gradient system as mobile phase. Chromatographic analysis was performed with a 4000 QTRAP® mass spectrometer using MRM in positive mode for CLBQ14 transition [M+H]+ m/z 257.919 → m/z 151.005, and IS (clioquinol) transition [M+H]+ m/z 305.783 → m/z 178.917. CLBQ14 was extracted from plasma and urine samples by protein precipitation. The retention times for CLBQ14 and IS were 1.31 and 1.40 minutes respectively. The standard curves were linear for CLBQ14 concentration ranging from 1 – 1000 ng/mL. The intra-day and inter-day accuracy and precision were found to be within 15 % of the nominal concentration. Extraction recoveries were greater than 96.3 % and 96.6 % from rat plasma and urine respectively, and there was no significant matrix effect from the biological matrices. CLBQ14 is stable in samples subjected to expected storage, preparation, and handling conditions. Pharmacokinetic studies revealed that CLBQ14 has a bi-exponential disposition in SD rats, is extensively distributed with a long plasma half-life and is eliminated primarily by liver metabolism.

Bioanalytical Assay Development and Validation for the Pharmacokinetic Study of GMC1, a Novel FKBP52 Co-chaperone Inhibitor for Castration Resistant Prostate Cancer

“…Interference of analyte signal by co-eluting PEG, used as an excipient in dosing solutions for pharmacokinetic studies, is well documented [ 19 , 20 ]. Signal interference by PEG 300 used in this study was evaluated by determining the precision and accuracy of six replicates of QC samples prepared in rat plasma spiked with 0.1% PEG 300 and 1% PEG 300, respectively.…”

<p>Pre-Clinical Pharmacokinetics, Tissue Distribution and Physicochemical Studies of CLBQ14, a Novel Methionine Aminopeptidase Inhibitor for the Treatment of Infectious Diseases</p>

“…A previously reported LC-MS/MS method was adopted for the determination of CLBQ14 in studies requiring the sensitivity and selectivity of mass spectrometry, Clioquinol was used as IS at 150 ng/mL. 29 Briefly, chromatographic separation was performed with a Shimadzu Nexera X2 UHPLC System (Columbia, MD) equipped with a Waters XTerra ® MS C 18 column (3.5 μm, 125Å, 2.1×50 mm, Milford, MA) at room temperature. A binary solvent system: Solvent A -0.2% formic acid in LC-MS grade water and Solvent B -0.2% formic acid in LC-MS grade acetonitrile was employed at a flow rate of 0.5 mL/ min.…”

“…42 Overall, the microsomal stability data suggest that the compound is primarily eliminated by liver metabolism, corroborating the observation in in vivo pharmacokinetic studies where 0.01% of the administered dose was excreted unchanged in urine. 29…”

“…Interestingly, although CLBQ14 has a high affinity for the kidneys, it is largely not excreted unchanged in urine -0.01% of the administered dose was excreted unchanged in urine in previous pharmacokinetic studies. 29 The higher concentration in the kidney may be driven by its higher perfusion; whether this will pose any safety risk is to be seen in safety lead optimization studies. In spite of this, the extensive distribution of CLBQ14 will be beneficial in chemotherapy targeting these tissues if this observation translates to humans.…”

“…We previously reported the development of an LC-MS/MS assay for the quantification of CLBQ14 and successfully applied it to estimate the intravenous pharmacokinetics of CLBQ14 following a 2, 5 and 10 mg per kg single IV bolus doses to SD rats; its pharmacokinetic parameters were estimated using a two compartmental model analysis. 29 In this study, we investigated the ADME properties of CLBQ14: intravenous (IV), oral (PO) and subcutaneous (SC) pharmacokinetic disposition, plasma and microsomal stability as well as the cytochrome P450 (CYP) enzymes involved in CLBQ14 metabolism. We evaluated the physicochemical properties of the molecule including solubility, lipophilicity and pH driven stability.…”