Bio-Analytical Method Development and Validation for the Quantitation of Relugolix in Plasma Samples by Lc-MS/Ms: Application to Bioavailability Study in Rabbits

Abstract

A novel, sensitive, and specific LC-MS/MS technique was developed for the quantification of Relugolix in plasma and validated as per the regulatory guidelines. Elution of Relugolix and Canagliflozin was achieved on Inertsil C18 (150mm × 2.10mm i.d, 5.0 μm particles size) column with acetonitrile and 0.1% HCOOH as a mobile phasic system in the fraction of 90:10 with a flowrate of 0.8 mL/min. The sciex API 6000 triple quadrupole mass equipment was executed with the mode of multiple reactions and m/z 624.18/127.03 for Relugolix and m/z 445.14/267.12 for the Canagliflozin, were the optimized transitions. Relugolix exhibited a rectilinear plot in the range of 3.9 – 1500.0 ng/mL concentrations. The LC–MS/MS validated methodology was efficiently utilized for the assessment of Relugolix in the rabbit plasma. From the pharmacokinetics data, the mean of Cmax and Tmax were 42.01 ± 0.99 ng/mL and 5.922 ± 0.157, individually. Plasma conc. reduced with t1/2 of 8.28 ± 0.174. AUC0→Last value obtained was 303.437 ± 8.01 ng. h/ml, respectively. In short, the method that was produced has been successfully tested, and pharmacokinetic parameters were shown after healthy rabbits were given Relugolix orally.