High-throughput bioanalytical method using automated sample preparation and liquid chromatography-atmospheric pressure ionspray mass spectrometry for quantitative determination of glybenclamide in human serum.

A liquid chromatographic-mass spectrometric (LC-MS) method with rapid automated sample preparation was developed and validated for determination of glybenclamide in human serum. Glybenclamide and its deuterated labelled internal standard were extracted from human serum samples by automated solid-phase extraction. The extract was injected into the LC-MS system for analysis. Glybenclamide and its internal standard were measured in multiple ion monitoring mode. The method was validated over a range of 10-1000 ng/ml with good accuracy and precision and was applicable for pharmacokinetic studies.

Phase I pharmacokinetic studies evaluating single and multiple doses of oral GW572016, a dual EGFR-ErbB2 inhibitor, in healthy subjects.

GW572016 is a dual EGFR-ErbB2 inhibitor that has promise as an anticancer agent. Two phase I studies were conducted to determine the safety, tolerability and pharmacokinetics of single and multiple doses given to healthy subjects. The single dose study evaluated two groups of eight subjects in an ascending dose, 4-way cross-over, while the multiple dose study evaluated twenty-seven healthy volunteers in an ascending dose, double-blind, randomized, placebo-controlled, staggered parallel design. No serious adverse events were seen in either study. The most common adverse events for subjects receiving GW572016 were headache, diarrhea, rash, cold symptoms, gastrointestinal symptoms, and elevated LFTs, which were similar between treatment and placebo groups. Absorption of single doses of GW572016 was slightly delayed, with median t(lag) of 15 minutes (range 0-90 minutes) and achieved peak serum concentrations at a median of three hours (range 1.5-6 hours) post-dose. Serum concentrations after multiple doses of GW572016 demonstrated no significant accumulation at the 25 mg dose, and approximately 50% accumulation at the 100 mg and 175 mg doses, achieving steady state in six to seven days. A modest time-dependent increase in serum concentrations also was detected with multiple doses of GW572016. Single and multiple oral doses of GW572016 were well tolerated in healthy subjects, and resulted in dose-related systemic exposure of GW572016.

Increasing throughput of parallel on-line extraction liquid chromatography/electrospray ionization tandem mass spectrometry system for GLP quantitative bioanalysis in drug development.

An approach is described with turbulent flow on-line extraction liquid chromatography/electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS) for GLP quantitative bioanalysis of a drug candidate. Two systems were built in-house with standard laboratory parts and equipments. One system consisted of one gradient HPLC pump, one isocratic pump, one ten-port valve, two turbulent flow columns, one analytical column, one autosampler and one mass spectrometer. Using this system, an injection-to-injection cycle time of 0.8 min was achieved. By adding an additional valve, another analytical column and an isocratic pump, the injection-to-injection cycle time decreased to 0.4 min. Validation results from the two systems showed that precision and accuracy were acceptable for GLP quantitative analyses. The system was utilized to support sample bioanalysis of a drug candidate in a first-time in-human clinical trial.