Epaminurad: A Promising hURAT1 Inhibitor for Effective and Safe Gout Management – Insights from a Phase 2b Dose-Finding Trial

Study Background and Disease Burden

Gout represents the most prevalent form of inflammatory arthritis globally, characterized by recurrent episodes of joint inflammation due to deposition of monosodium urate crystals facilitated by hyperuricemia. Effective management hinges on sustained lowering of serum urate (sUA) levels to prevent flares and long-term joint damage. Despite advances, currently approved urate-lowering therapies such as xanthine oxidase inhibitors (e.g., allopurinol, febuxostat) and uricosurics carry limitations including incomplete efficacy, adverse reactions, and contraindications in subsets of patients. Therefore, there remains a significant unmet need for novel, effective, and well-tolerated agents for hyperuricemia management in gout.

Epaminurad is a recently developed selective inhibitor of human urate transporter 1 (hURAT1), a renal transporter responsible for reabsorption of urate in the proximal tubule. By inhibiting hURAT1, epaminurad enhances renal uric acid excretion, thereby lowering serum uric acid levels. Previous phase 1 studies demonstrated promising urate-lowering effects in healthy volunteers. The current phase 2b study aimed to evaluate the efficacy and safety of epaminurad at varying doses compared with placebo in patients with gout and elevated sUA, and to establish an optimal dosing regimen.