A sensitive and accurate liquid chromatography–tandem mass spectrometry method for quantitative determination of the novel hepatitis C NS5A inhibitor BMS-790052 (daclastasvir) in human plasma and urine

A liquid–liquid extraction (LLE) and liquid chromatography–tandem mass spectrometry (LC–MS/MS) methods have been developed and validated for the quantification of BMS-790052 (daclastasvir) in human plasma and urine. The samples were extracted with methyl-t-butyl ether (MTBE) before analyzing by an API 4000 mass spectrometer which was operated in a multiple reaction monitoring (MRM) mode for detection of positively charged ions of BMS-790052 and its internal standard, 13C10-BMS-790052. The standard curves ranged from 0.050 to 50.0 ng/mL for BMS-790052 in human plasma, and 1.00–1000 ng/mL in human urine. The intra-assay precision (%CV), based on four levels of analytical QCs (low, geometric mean, mid and high), was within 8.6%; inter-assay precision (%CV) was within 6.7% for both plasma and urine methods, and the mean assay accuracy (%Dev) was within ±3.0% for both plasma and urine methods. The ruggedness of this accurate, precise, and selective LLE–LC–MS/MS method has been demonstrated in the successful analysis of several thousand clinical study samples.