LC-MS quantification of protein drugs: validating protein LC-MS methods with predigestion immunocapture.

A refinement of protein LC-MS bioanalysis is to use predigestion immunoaffinity capture to extract the drug from matrix prior to digestion. Because of their increased sensitivity, such hybrid assays have been successfully validated and applied to a number of clinical studies; however, they can also be subject to potential interferences from antidrug antibodies, circulating ligands or other matrix components specific to patient populations and/or dosed subjects. The purpose of this paper is to describe validation experiments that measure immunocapture efficiency, digestion efficiency, matrix effect and selectivity/specificity that can be used during method optimization and validation to test the resistance of the method to these potential interferences. The designs and benefits of these experiments are discussed in this report using an actual assay case study.

Empagliflozin (BI 10773), a Potent and Selective SGLT2 Inhibitor, Induces Dose-Dependent Glucosuria in Healthy Subjects.

Empagliflozin is an orally available, selective inhibitor of sodium glucose cotransporter 2. In this study, single oral doses of empagliflozin from 0.5 to 800 mg were not associated with any clinically significant safety concerns in healthy male volunteers. The incidence of adverse events (AEs) was similar in subjects receiving placebo (22.2%) or empagliflozin (25.0%) in the single rising dose part of the study and after 50 mg empagliflozin under fed (28.6%) or fasted (28.6%) conditions. The most frequent AE was headache. No clinically relevant changes in laboratory or electrocardiogram (ECG) measurements were observed. Single oral doses of empagliflozin were rapidly absorbed, reaching peak levels after 1.0-2.1 hours. Increases in empagliflozin exposure were roughly dose-proportional and a dose-dependent increase in urinary glucose excretion was observed for empagliflozin doses up to 100 mg. After ingestion of 50 mg empagliflozin in conjunction with a high-fat, high-calorie meal, no clinically relevant changes in exposure were found, indicating that empagliflozin can be administered independent of food. Empagliflozin up to 800 mg did not generate clinically significant safety concerns in healthy male subjects. The pharmacokinetic properties of empagliflozin support once daily administration independent of food.