Healthy volunteer samples
Venous blood was collected from three healthy Thai volunteers given a single dose of IVM (400 µg/kg) (NCT02568098) (Kobylinski et al., 2020). The blood samples were collected in sodium heparin tubes at 24 hours post IVM ingestion and kept frozen at -80°C until LC-MS/MS analysis. For metabolite extraction, whole blood samples were thawed at ambient temperature, vortexed briefly, and centrifuged at 3000×g for 5 min at 20°C. 50 µL of plasma was transferred into a new microcentrifuge tube and mixed with 200 µL of cold acetonitrile. Tubes were vortexed for 10 minutes at ambient temperature and centrifuged at 1100×g for 5 min at 20°C. The supernatant was collected, evaporated in speed vacuum, and kept at -80°C freezer until LC-MS/MS analysis.