Arthrosi Therapeutics, Inc., a late-stage biotechnology company, announced that it has successfully completed patient enrollment in its pivotal Phase 3 REDUCE 1 trial for pozdeutinurad (formerly AR882). This investigational therapy is a highly potent, selective next-generation URAT1 inhibitor designed to reduce serum urate (sUA) levels, prevent flares, and dissolve tophi in patients with gout and tophaceous gout.
A Major Milestone in the REDUCE Program
- REDUCE 1 enrollment completed ahead of schedule: 750 patients enrolled worldwide.
- REDUCE 2 already fully enrolled earlier in Q1 2025.
- Both trials target patients with inadequate response to existing urate-lowering therapies (ULTs).
Dr. Robert T. Keenan, Chief Medical Officer at Arthrosi, called this milestone “a critical step toward delivering a much-needed, differentiated treatment option for patients with gout and tophaceous gout.”
He emphasized the strong demand among both clinicians and patients for safer, more effective therapies.
Arthrosi expects to report data:
- REDUCE 2 results → Q2 2026.
- REDUCE 1 results → Q4 2026.
- Both trials will support a planned NDA submission for pozdeutinurad.
Inside the REDUCE 1 Study
- Design: 12-month, randomized, double-blind, placebo-controlled.
- Participants: 750 global patients (majority are inadequate responders to ULTs).
- Treatment arms:
- Pozdeutinurad 50 mg
- Pozdeutinurad 75 mg
- Placebo - Primary endpoint: Reduction of serum urate (sUA) by Month 6.
- Secondary endpoints: Reduction of tophi and flares.
The company anticipates a comprehensive data update in late 2026.
Why Pozdeutinurad Matters
Pozdeutinurad has already shown encouraging efficacy and safety in Phase 2 trials. Notable results include:
- Stronger performance versus standard of care (SOC).
- Achievement of complete resolution of tophi in a Phase 2b study.
Its selective URAT1 inhibition offers the potential for best-in-class performance in lowering urate, reducing painful flares, and resolving tophi, which remain major challenges in treating advanced gout.
Understanding Gout and Tophaceous Gout
- Prevalence: ~13 million Americans have gout. Of these, about 2 million suffer from tophaceous gout.
- Impact: A painful form of inflammatory arthritis that reduces mobility, functionality, and quality of life.
- Cause: Crystallization of uric acid in joints and soft tissues, leading to painful flare-ups and chronic symptoms.
- Role of kidneys: Normally filter and excrete uric acid. In over 90% of gout patients, underexcretion leads to elevated sUA levels and crystal deposits.
Monitoring and controlling sUA levels is essential for both prevention and long-term management.
About Arthrosi Therapeutics
Headquartered in San Diego, CA, Arthrosi Therapeutics is advancing pozdeutinurad through its pivotal Phase 3 program. The company’s mission is to deliver a safer, more effective treatment for patients struggling with gout and tophaceous gout, addressing a significant unmet medical need.
Bottom Line
With both REDUCE 1 and REDUCE 2 fully enrolled, Arthrosi is on track to deliver late-stage clinical data by 2026. If successful, pozdeutinurad could become a best-in-class option for gout patients, particularly those who do not respond well to existing urate-lowering therapies.
