Validation of a sensitive simultaneous LC-MS/MS method for the quantification of novel anti-cancer thiazolidinedione and quinazolin-4-one derivatives in rat plasma and its application in a rat pharmacokinetic study.

Thiazolidinediones and quinazolin-4-ones compounds, previously known for their activity against Type 2 diabetes and antifungal activity respectively, are currently being investigated for their anti-cancer activity. The determination of pharmacokinetic parameters for these two classes of compounds using a simultaneous chromatographic method with a low detection limit is a challenge. In this study, a highly sensitive and simultaneous LC-MS/MS-based bioanalytical method was developed and validated in rat plasma for the estimation of four novel anti-cancer compounds, BIT-15-67 and BNT-11, belonging to the Thiazolidinedione class, and BNUA-108 and BNUA-48, from the quinazolin-4-one class. The analytes were extracted from plasma samples by protein precipitation and separated on a short reverse phase Hypersil Phenyl BDS, 50 × 4.6 mm, 2.4 µm column at a column oven temperature of 40 °C. An isocratic mobile phase, a 20:80 (v/v) mixture of 5 mM ammonium acetate solution and acetonitrile containing 0.1% formic acid, was used for the elution at a flow rate of 0.4 mL/min. The analytes and internal standard, sulfaphenazole, were quantified in the multiple reaction monitoring mode using positive electrospray ionization with specific pair of mass by charge ratio. All standard validation parameters were assessed as per current bioanalytical method validation guidelines in rat plasma. The area response for the four analytes was found to be linear over the concentration range of 1.00 to 1000 ng/mL in rat plasma. The signal to noise at LLOQ of 1 ng/mL was adequate for application to different pre-clinical studies. The intra- and inter-day precision were <11% and accuracy deviated -1.8 to 9.60% from the nominal. The mean recovery was high (about 90%) and consistent for all the analytes over the linear dynamic range of the method. This simple, robust and validated method can be employed to determine the rat plasma concentrations of the four selected anticancer compounds in preclinical studies such as the pharmacodynamic and the pharmacokinetic studies including tissue distribution and excretion, and the toxicokinetic studies. In this study, pharmacokinetic parameters were determined using this method for all the four compounds individually following intravenous administration in rats.

In vitro metabolism, disposition, preclinical pharmacokinetics and prediction of human pharmacokinetics of DNDI-VL-2098, a potential oral treatment for Visceral Leishmaniasis.

The in vitro metabolism and in vivo pharmacokinetic (PK) properties of DNDI-VL-2098, a potential oral agent for Visceral Leishmaniasis (VL) were studied and used to predict its human pharmacokinetics. DNDI-VL-2098 showed a low solubility (10µM) and was highly permeable (>200nm/s) in the Caco-2 model. It was stable in vitro in liver microsomes and hepatocytes and no metabolite was detectable in circulating plasma from dosed animals suggesting very slow, if any, metabolism of the compound. DNDI-VL-2098 was moderate to highly bound to plasma proteins across the species tested (94-98%). DNDI-VL-2098 showed satisfactory PK properties in mouse, hamster, rat and dog with a low blood clearance (<15% of hepatic blood flow except hamster), a volume of distribution of about 3 times total body water, acceptable half-life (1-6h across the species) and good oral bioavailability (37-100%). Allometric scaling of the preclinical PK data to human gave a blood half-life of approximately 20h suggesting that the compound could be a once-a-day drug. Based on the above assumptions, the minimum efficacious dose predicted for a 50kg human was 150mg and 300mg, using efficacy results in the mouse and hamster, respectively.