Effect of Oral Absorbent Therapy on Kidney Progression According to the Cause of CKD

Background: Oral absorbent therapy with DW-7202 (Renemezin®) and AST-120 (Kremezin®) slows the progression of CKD. The aim of this study is to investigate whether the mitigating effect of oral absorbents on CKD progression varies according to the etiology of CKD. Methods: This retrospective study included 490 patients at Konkuk University Medical Center who took absorbents for over three months between January 1, 2016, and August 31, 2023. Serum Cr levels were compared annually from the start of treatment until April 30, 2024, or the initiation of renal replacement therapy. The slope of serum Cr was compared among CKD patients with different causes using multilevel mixed-effects linear regression. Results: The most common cause of CKD was DM (54.9%), followed by HTN (22.7%), GN (7.7%), ADPKD (2.8%), and unknown etiology (11.9%). Baseline Cr levels were not significantly different among the groups (P=0.39), but were significantly different after one year (P=0.02). After drug administration, serum Cr levels significantly increased compared to baseline in all groups (Figure 1, p<0.05), with the highest increase observed in the GN group. Compared to the GN group, the slope of serum Cr increases was significantly lower in the HTN, DM, ADPKD, and unknown etiology groups (Table 1, p<0.01). Conclusion: These findings suggest that oral absorbent therapy has different effects depending on the cause of CKD. The treatment significantly alleviated CKD progression in patients with HTN, DM, ADPKD, and unknown etiology compared to those with GN. Funding: Commercial Support - DAEWOONG PHARMACEUTICAL CO.,LTDFigure 1. Changes in Serum Cr Before and After Drug Therapy Over One Year in Each Etiology Group Table 1. Comparison of the Slope of Creatinine Increase in Each Etiology Group Following Oral Absorbent Therapy - Cause of CKD Slope of Creatinine increase (µmol/L/year) (95% CI) p Value HTN 19.3 (4.63 - 33.8) <0.01 DM 28.3 (18.3 - 38.3) <0.01 GN 84.4 (62.2 - 106.6) Reference ADPKD 22.9 (-12.7 - 58.4) <0.01 Unknown 19.6 (-1.48 - 40.7) <0.01