Performance and Hemocompatibility of a Novel Polysulfone Dialyzer: A Randomized Controlled Trial

Abstract

Background: High-flux dialyzers shall effectively remove uremic toxins and be hemocompatible to minimize intradialytic humoral and cellular stimulation and long-term impact on patient outcomes. A new dialyzer with a modified membrane surface has been tested for performance and hemocompatibility. Methods: This multicenter, prospective, randomized, cross-over study applied for one week each the new polysulfone-based FX CorAL 600 (Fresenius Medical Care, Bad Homburg, Germany), the polyarylethersulfone-based Polyflux 170H (Baxter Healthcare Corporation, Deerfield, IL, USA) and the cellulose-triacetate-based SureFluxTM 17UX (Nipro Medical Europe, Mechelen, Belgium) to assess non-inferiority of removal rate of β2-microglobulin of the FX CorAL 600. Performance was assessed by removal rate and clearance of small and middle molecules. Hemocompatibility was assessed through markers of complement, cell activation, contact activation and coagulation. Results: Of 70 patients, 58 comprised the intention-to-treat population. The removal rate of β2-microglobulin of the FX CorAL 600 was non-inferior to both comparators (P<0.0001 vs SureFluxTM 17UX; P=0.0006 vs Polyflux 170H), and superior to SureFluxTM 17UX. The activation of C3a and C5a with FX CorAL 600 was significantly lower 15 min after treatment start than with SureFluxTM 17UX. The activation of sC5b-9 with FX CorAL 600 was significantly lower over the whole treatment than with SureFluxTM 17UX, and lower after 60 min than with Polyflux 170H. The treatments with FX CorAL 600 were well tolerated. Conclusions: FX CorAL 600 efficiently removed small and middle molecules, showed a favorable hemocompatibility profile and was associated with a low frequency of adverse events in the present study with a limited patient number and follow-up time. Further studies with longer observation times are warranted to provide further evidence supporting the use of the new dialyzer in a wide range of therapeutic options and long-term treatments of hemodialysis patients to minimize the potential impact on inflammatory processes.

Randomized comparison of three high-flux dialyzers during high-volume online hemodiafiltration—the comPERFORM study

“…The β2-m RRs in the comPERFORM study were somewhat higher (range 72.7–75.5%) than in an earlier study comparing FX CorAL 600 with Polyflux 170H and SUREFLUX-17UX (70.3% and 67.7% for the two dialyzers with synthetic membranes; 51.3% for the cellulose-based dialyzer) [ 13 ]. This difference is explained by different treatment modalities and confirms observations of other authors that higher RRs can be obtained with higher substitution and blood flow rates [ 16 , 21 , 22 ].…”

“…This difference is explained by different treatment modalities and confirms observations of other authors that higher RRs can be obtained with higher substitution and blood flow rates [ 16 , 21 , 22 ]. In the study reported by Ehlerding et al [ 13 ], substitution flow rates were set manually to around 70 mL/min, whereas in comPERFORM they were automatically set by the dialysis machines and reached a mean of 92 mL/min. In addition, blood flow was slightly higher in the comPERFORM study (∼325 mL/min versus 305 mL/min).…”

“…For the primary variable β2-m RR, the non-inferiority margin of −2% and the standard deviation were taken from earlier studies with FX CorAL 600 dialyzer and the number of patients needed for this cross-over study was estimated accordingly [ 13 , 14 ]. A total of independent patients were required, fixing the error level at α = 2.5% for a one-sided test and aiming at a power of 1 − β = 80%.…”

“…Two earlier clinical trials evaluated the safety and performance of FX CorAL [ 13 ]. The first compared FX CorAL with two other dialyzers of the FX series (FMC) while the second compared FX CorAL to SUREFLUX by Nipro and Polyflux by Baxter/Gambro (Deerfield, IL, USA).…”

“…Moreover, haemocompatibility analyses showed significantly lower C5a and sC5b-9 complement activation for FX CorAL than for two comparators from the FX series. Compared with Polyflux and SUREFLUX, FX CorAL activated complement sC5b-9 significantly less [ 13 ].…”