Can we finally personalize MTX dosing in #RA? liquid chromatography-tandem mass spectrometry (LC-MS/MS) assay (n=59): MTX-PG3 levels ↑ with dose and age, ↓ with higher disease activity and concomitant biologics. Route (oral vs SC) didn't matter. @RheumNow #EULAR2026 POS0251