This clinical trial investigates whether the composition of dialysate influences hemodialysis-associated thromboinflammation. Specifically, it evaluates the effects of magnesium concentration and acid type in dialysate on immune cell activation and thromboinflammatory responses. Patients participating to the multicentric pilot OMAGOD trial will be invited to participate to this monocentric plus study. In the pilot OMAGOD trial, participants will undergo standard hemodialysis (3 sessions/week, 4 hours each) and receive three different dialysate compositions in a crossover design. Each treatment phase lasts two weeks (six sessions). For the local plus study, during selected sessions (3 per patient - midweek hemodialysis session of the last week of a treatment period), blood samples will be collected (at baseline, hourly, and at the end of dialysis) and additionally, after each session, the used dialysis circuit will be rinsed to recover adherent cells. The study aims to: * Assess whether the dialysate composition influences leukocyte and platelet activation . * Evaluate whether the dialysate composition influences neutrophil extracellular trap (NET) formation. * Identify novel biomarkers of thromboinflammation using transcriptomic analysis of immune cells.