Safety of a Novel Dialyzer Containing a Fluorinated Polyurethane Surface-Modifying Macromolecule in Patients with End-Stage Kidney Disease

Abstract

Background: By inhibiting the adsorption of protein and platelets, surface-modifying macromolecules (SMMs) may improve the hemocompatibility of hemodialyzers. This trial aims to assess the performance and safety of a novel dialyzer with a fluorinated polyurethane SMM, Endexo™.

Methods: This prospective, sequential, multicenter, open-label study (NCT03536663) was designed to meet regulatory requirements for clinical testing of new hemodialyzers, including assessment of the in vivo ultrafiltration coefficient (Kuf). Adults prescribed thrice-weekly hemodialysis were eligible for enrollment. After completing 12 hemodialysis sessions with an Optiflux® F160NR dialyzer, patients received 38 sessions with the dialyzer with Endexo. Evaluated parameters included the in vivo Kuf of the dialyzer with Endexo extent of removal of urea, albumin, and β2-microglobulin (β2M), as well as complement activation.

Results: Twenty-three patients received 268 hemodialysis treatments during the Optiflux period, and 18 patients received 664 hemodialysis treatments during the Endexo period. Three serious adverse events were reported, and none of them were considered device related. No overt complement activation was observed with either dialyzer. Both dialyzers were associated with comparable mean increases in serum albumin levels from pre- to posthemodialysis (Optiflux: 7.9%; Endexo: 8.0%). These increases can be viewed in the context of a mean increase in hemoglobin of approximately 5% and a mean ultrafiltration volume removed of approximately 2.2 L. The corrected mean β2M removal rate was 47% higher during the Endexo period (67.73%). Mean treatment times (208 vs. 205 min), blood flow rates (447.7 vs. 447.5 mL/min), dialysate flow rates (698.5 vs. 698.0 mL/min), urea reduction ratio (82 vs. 81%), and spKt/V (2.1 vs. 1.9) were comparable for the Endexo and Optiflux periods, respectively. The mean (SD) Kuf was 15.85 (10.33) mL/h/mm Hg during the first use of the dialyzer with Endexo (primary endpoint) and 16.36 (9.92) mL/h/mm Hg across the Endexo period.

Conclusions: The safety of the novel dialyzer with Endexo was generally comparable to the Optiflux dialyzer, while exhibiting a higher β2M removal rate.

Keywords: Chronic hemodialysis; Dialyzer; Surface-modifying macromolecule; β2-Microglobulin.

Conflict of interest statement

A.A.Z., M.T., C.-H.H., S.A., C.M., and R.J.K. are or were employees of the Fresenius Medical Care Renal Therapies group during the study.

© 2021 The Author(s). Published by S. Karger AG, Basel.

Figures

Fig. 1

Study design and select schedule of assessments. Not all visits and assessments are listed. F/U, follow-up; HD hemodialysis; BUN, blood urea nitrogen; β2M, beta-2 microglobulin; CBC, complete blood count; TMP, transmembrane pressure; UFR, ultrafiltration rate; V, visit; AEs, adverse events.

Fig. 2

Box plot of β2M removal rates by the dialyzer in the analysis population. Box represents interquartile range and median (horizontal line); whiskers represent adjacent values (i.e., highest value within Q3 + [1.5 × IQR] and lowest value within Q1 + [1.5 × IQR]); +, mean value; □, outlier value. Removal rate calculated as (pre-HD β2M − corrected post-HD β2M)/pre-HD β2M × 100. HD, hemodialysis; IQR, interquartile range; β2M, beta-2-microglobulin.

Fig. 3

Box plot of percentage changes in serum albumin concentration by the dialyzer (pre-HD to post-HD) in the analysis population. Box represents interquartile range and median (horizontal line); whiskers represent adjacent values (i.e., highest value within Q3 + [1.5 × IQR] and lowest value within Q1 + [1.5 × IQR]); +, mean value; □, outlier value. Percent change = (post-HD − pre-HD)/pre-HD × 100. HD, hemodialysis; IQR, interquartile range.