Bioanalysis.
The analysis of FMGX and MGX in acidified EDTA 4-mL plasma samples was performed at the Bioanalytical Laboratory of ICON (formerly PRA Health Sciences, Assen, The Netherlands) using a validated liquid chromatography-mass spectrometry/mass spectrometry (LC-MS/MS) method. Quality control procedures and acceptance criteria were based on the U.S. FDA Guidance for Industry-Bioanalytical Method Validation (