English translation of the original Korean article: 통풍 신약 ‘에파미뉴라드’, 아시아 임상 3상서 표준치료제보다 우수한 효과 확인
South Korean pharmaceutical company JW Pharmaceutical announced on August 11 that its investigational gout drug candidate ‘Epaminurad’ (URC102) demonstrated superior uric-acid-lowering efficacy compared to the standard treatment in a multinational Phase 3 trial in Asia. The result could open a new treatment option for gout patients in Korea.
Why It Matters
Gout is a metabolic disease in which elevated blood uric acid levels cause urate crystals to accumulate in the joints, triggering intensely painful acute inflammatory arthritis. Driven by Westernized diets, an aging population, and rising rates of metabolic syndrome, the number of gout patients in Korea has been steadily increasing. While urate-lowering drugs such as febuxostat are widely prescribed, a significant share of patients in real-world practice still fail to reach their target serum uric acid level, sustaining demand for new therapeutic options.
What the Trial Found
The Phase 3 trial was conducted at 52 institutions across five Asian countries — South Korea, Taiwan, Thailand, Malaysia, and Singapore — enrolling 612 gout patients. It was a multicenter, randomized, double-blind, active-controlled study comparing two doses of Epaminurad (6mg and 9mg) against febuxostat (40mg and 80mg), the most widely prescribed standard treatment in Korea.
The primary 6mg dose demonstrated not just non-inferiority but statistical superiority over febuxostat 40mg in reducing blood uric acid levels. The target serum uric acid response rate was 50.0%, with 76 of 152 patients meeting the threshold. The 9mg dose, however, did not meet the statistical non-inferiority criterion for the primary endpoint versus febuxostat 80mg, though the gap in target response rates was narrow — 59.6% (87/146) for the 9mg group versus 63.3% (95/150) for febuxostat 80mg, a difference of roughly 4 percentage points.
The Mechanism
Epaminurad belongs to a class of drugs known as uricosurics, which work by selectively inhibiting URAT1, the kidney transporter responsible for reabsorbing uric acid back into the bloodstream. This mechanism differs from existing xanthine oxidase inhibitors such as febuxostat and allopurinol, which instead reduce uric acid production — raising the possibility that Epaminurad could serve as a combination or alternative option for patients who do not respond adequately to current treatments.
Limitations and Open Questions
The failure of the 9mg dose to meet the non-inferiority bar for its primary endpoint suggests further dose optimization work remains. The results disclosed so far are topline figures; detailed adverse-event data and long-term follow-up have not yet been released. Even after trial completion, regulatory review and post-marketing safety monitoring still lie ahead before the drug reaches patients.
Outlook and Everyday Impact
JW Pharmaceutical said it aims to file for domestic regulatory approval in Korea by 2027 based on these results. If approved, the drug would give gout patients who do not respond well to — or experience side effects from — existing treatments a new option. Because gout tends to recur and, if left untreated, can lead to chronic joint damage and kidney complications, a domestically developed new drug could also improve treatment accessibility and affordability.
Phase 3 Results at a Glance
| Metric | Epaminurad 6mg | Epaminurad 9mg |
|---|---|---|
| Comparator | Febuxostat 40mg | Febuxostat 80mg |
| Primary endpoint | Non-inferiority and superiority met | Non-inferiority not met |
| Target uric acid response rate | 50.0% (76/152) | 59.6% (87/146) vs. 63.3% comparator |
References
- Hankyung, “JW Pharmaceutical succeeds in global Phase 3 trial of gout drug” (Aug 11, 2026)
- KPA News, “JW Pharmaceutical’s gout drug Epaminurad demonstrates efficacy of 6mg dose in Phase 3” (Aug 12, 2026)
- JW Pharmaceutical press release (Aug 11, 2026)
