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Abstract: FR-PO819

Performance and Self-Perceived Restless Leg Syndrome Associated with Use of High-Flux Dialyzers: Results from the eMPORA III Trial

Session Information

Category: Health Maintenance, Nutrition, and Metabolism

  • 1500 Health Maintenance, Nutrition, and Metabolism


  • Larkin, John W., Fresenius Medical Care, Waltham, Massachusetts, United States
  • Griesshaber, Bettina, Fresenius Medical Care Deutschland GmbH, Bad Homburg, Hessen, Germany
  • Erlenkoetter, Ansgar, Fresenius Medical Care Deutschland GmbH Werk Sankt Wendel, Sankt Wendel, Saarland, Germany
  • Ronova, Petra, Fresenius Nephrocare Praha 9 - Vysocany, Prague, Czechia
  • Krizsan, Maria, FMC, Péterfy II. Dialízis Központ, Budapest, Hungary
  • Braun, Jennifer, Fresenius Medical Care Deutschland GmbH, Bad Homburg, Hessen, Germany
  • Stauss-Grabo, Manuela, Fresenius Medical Care Deutschland GmbH, Bad Homburg, Hessen, Germany

The eMPORA III study was a prospective, multicenter, crossover trial with 4-week randomized treatment sequences comparing the performance and hemocompatibility of dialyzers (FX CorAL 600 vs two comparators) in post-dilution online hemodiafiltration (HDF). Primary outcome was beta-2 microglobulin (B2M) removal and self-perceived restless leg syndrome (RLS) was also assessed using the International RLS Study Group Rating Scale survey.


Medically stable adult HDF patients with a functioning fistula/graft were recruited from 8 centers in Germany, Czechia, Hungary (NCT04714281). B2M removal rate (B2M RR) pre-HDF vs 240 min was measured in week 3 of each 4-week treatment period. RLS survey was administered at baseline and the end of periods. Survey captures the severity and impact of symptoms in the prior week on a 0 (no RLS) to 40 (very severe RLS) point scale, and has 2 subscales. Global RLS scores >10 points imply moderate-to-very severe RLS symptoms. Effect of dialyzers were estimated using a linear mixed model adjusted for center and patient in the intention-to-treat (ITT) group.


Study enrolled 82 subjects (76 ITT group, mean age=67.0±15.6 years, 26.3% female, 34.2% diabetes). FX CorAL 600 showed a +0.60±0.39% and +1.82±0.38% higher B2M RR vs FX CorDiax 600 (non-inferiority p<0.0001; superiority p=0.0606) and xevonta Hi 15 (non-inferiority p<0.0001; superiority p<0.0001). Mean global RLS score was 3.2±6.24 (Figure 1). FX CorAL 600 showed a +0.24±0.54 and +0.33±0.54 point change in global RLS scores vs FX CorDiax 600 (p=0.65) and xevonta Hi 15 (p=0.54); consistent findings were found for subscale scores.


FX CorAL 600 provided a higher B2M RR than comparator dialyzers. RLS symptoms were consistent between dialyzer types. Average scores indicate mild-to-no RLS among trial participants, yet some patients reported severe symptoms. Higher middle molecule clearance may not affect RLS symptoms, but more investigations are needed with longer follow-up and should consider patients with moderate-to-severe symptoms.


  • Commercial Support – Fresenius Medical Care