Abstract Background and Aims Dialysate flow rate (Qd) has minimal effect in removal of molecules in hemodialysis, allowing to use lower amounts of dialysate with no effect in clearance of molecules. According to recent literature, Expanded hemodialysis (HDx) improves the clearance of middle size molecules, diminishing the effect of Qd in adequacy. We found no data about clearance at different dialysate flow rates in HDx. Our aim is to evaluate the clearance of middle molecules (beta 2 microglobuline [Mβ2], interleukin-6 [IL-6], interleukin-10 [IL-10 light chains (CLL-κ -λ) with HDx at different Qd using membranes TheranovaMR in patients with body weight less than 70 Kg. Method We performed an observational retrospective analysis of clearance of Mβ2, IL-6, IL-10, CLL-κ; CLL-λ in HDx using TheranovaMR filters with Qd 400 mL/min and 500 mL/min. We performed variance analysis, T student test and Wilcoxon test. Data were extracted from an HDx multicentric trial performed in Bogotá, Colombia in 2018. Results 11 (47%) patients received Qd 400 mL/min and 12 (52.1%) patients with Qd 500ml/min. Demographic data are included in table 1. We found no differences in reduction rate of mid-molecules. (Table 2) We found that lower water consume in the Qd 400 mL/min group, with water savings of 24 Liters/patient (13824 L in 12 weeks of follow up). (Table 3) Conclusion Expanded hemodialysis seems to allow diminishing Qd rate without changes in mid-size molecules clearance.