A Multidisciplinary Roadmap for an Oral Therapeutic Strategy to Lower Protein-Bound Uremic Toxins in Chronic Kidney Disease

Background. Chronic kidney disease (CKD) is a major global health burden; recent estimates place the adult prevalence at approximately 0.79 billion people (95% uncertainty interval 0.74–0.84 billion), with approximately 4.6 million receiving kidney replacement therapy and about 1.5 million deaths attributable to CKD each year. Among the retained solutes that drive progression and cardiovascular morbidity, the protein-bound uremic toxins (PBUTs) indoxyl sulfate (IS) and p-cresyl sulfate (PCS) are pivotal. Both are more than 90% bound to human serum albumin (HSA) and are eliminated mainly by proximal tubular secretion through organic-anion transporters, a function that haemodialysis cannot replicate because only the small unbound fraction crosses the membrane.Objective and approach. This is a conceptual, hypothesis-generating roadmap. We propose an oral strategy that pairs (i) a high-affinity albumin-binding displacer (a polyphenol such as salvianolic acid B) to increase the clearable free fraction of IS and PCS, with (ii) a co-formulated intestinal sorbent that captures gut-derived precursors and enterally handled toxin for faecal elimination, delivered by a pH-responsive enteric nanoparticle. The design is developed with AI-guided medicinal chemistry, nanotechnology, and systems pharmacology.Findings (model-based, no empirical data). A competitive-binding model with assumed affinities predicts a 33–56% reduction in albumin-bound toxin over a plausible displacer window; an illustrative two-compartment pharmacokinetic model with reduced clearance sustains exposure over 24 h; and a Monte-Carlo analysis (±20% parameter variation) indicates moderate output dispersion (area-under-curve coefficient of variation ≈7%). These are transparent model outputs contingent on assumed parameters, not experimental or in-vivo results.Conclusions. We frame the concept as a conditional-benefit hypothesis rather than a general-purpose therapeutic claim: it is applicable only to the subset of CKD patients in whom a functioning clearance sink exists (residual tubular secretion, hepatobiliary handling, intradialytic removal, or gut adsorption), and it is explicitly not proposed for fully anuric patients without dialysis support, in whom displacement alone could increase tissue toxin exposure rather than lower it. Within that defined population, the concept is best regarded as a candidate dialysis-sparing adjunct rather than a dialysis replacement. Its central, falsifiable premise—that raising the free toxin fraction yields net elimination rather than redistribution—must be confirmed in vitro and in vivo before any claim of benefit is warranted. We outline explicit falsification criteria and call for collaborative preclinical validation.