Aims: This double-blind, randomized, parallel, placebo-controlled investigation evaluated the effects of cross-linked polyelectrolyte (CLP) on serum potassium and measures of congestion in patients with heart failure (HF) and chronic kidney disease (CKD).
Methods and results: The primary endpoint was change in serum potassium over time. Exploratory endpoints included: weight, physician and patient assessment of exertional dyspnoea, effect on N-terminal pro brain natriuretic peptide (NT-proBNP) levels, New York Heart Association (NYHA) classification, 6 min walk test (6MWT), and quality of life by Kansas City Cardiomyopathy Questionnaire (KCCQ). Serum potassium was similar in CLP (n =59) and placebo (n =52) groups throughout the 8-week study. Weight loss was greater in the CLP than in the placebo group at Weeks 1 (P =0.014) and 2 (P =0.004), and this trend continued until the end of the study. After 8 weeks, by physician assessment, the percentage of patients experiencing marked or disabling dyspnoea tended to be lower in the CLP than in the placebo group (7.3% vs. 23.9%, P =0.128). Fewer patients in the CLP than in the placebo group had NT-proBNP levels >1000 pg/mL at Week 4 (P =0.039) and Week 8 (P =0.065). The proportion of patients improving by at least one NYHA functional class over the study was higher in the CLP than in the placebo group (48.8% vs. 17.4%; P =0.002). Effects on 6MWT at Week 8 (p =0.072) and quality of life (overall KCCQ score) at Week 4 (p =0.005) and 8 (P =0.062) all favoured the CLP cohort. Four treatment-unrelated deaths occurred in the CLP group and none in the placebo group (P =0.056).
Conclusion: In advanced, symptomatic HF with CKD, CLP is associated with beneficial clinical effects without significant serum potassium changes.
Trial registration: NCT01265524.