Arthrosi to Present More Positive Phase 2 Data for AR882 at 26th APLAR Congress

Arthrosi Therapeutics, Inc., a biotechnology firm in its late stages of development, recently shared promising results from a sub-population analysis of its Phase 2 clinical program focused on gout patients in the Asia-Pacific region. These findings were presented at the 26th Asia-Pacific League of Associations for Rheumatology Congress in Singapore.

The company's Chief Medical Officer, Dr. Robert T. Keenan, expressed enthusiasm about the new data, underscoring the significant unmet needs of gout patients worldwide. He highlighted that AR882, the company's investigational drug, shows strong potential to reduce serum urate levels and tophi, while maintaining a favorable safety profile compared to current standard treatments. Notably, 83% of patients receiving a 75mg dose of AR882 achieved serum urate levels below 5 mg/dL, crucial for resolving tophi and reducing flare-ups. Arthrosi plans to continue evaluating AR882 in its ongoing Phase 3 REDUCE 2 study and another confirmatory Phase 3 study set to begin later this year.

The Phase 2 program involved 68 gout patients from Australia, New Zealand, and Taiwan. Of these, 53 patients were part of a study where participants were randomized into three groups to receive either a 50mg dose of AR882, a 75mg dose of AR882, or a placebo daily for 3 months. The other 15 patients participated in a Phase 2b study focused on subcutaneous tophi, receiving either 75mg of AR882, a combination of 50mg AR882 with 300mg allopurinol, or 300mg allopurinol followed by a combination with 75mg AR882 for a total of 12 months. Serum urate levels were monitored at intervals of 3, 6, and 12 months, with caliper measurements and dual energy computed tomography (DECT) conducted at baseline, 6, and 12 months. Safety was continuously assessed throughout the study.

Key findings from these studies include:
- Both the 75mg AR882 group and the 50mg AR882 plus allopurinol group exhibited significant and lasting reductions in serum urate levels over 3, 6, and 12 months.
- The mean baseline serum urate level was 8.7 mg/dL. After three months, median serum urate levels dropped to 4.9 mg/dL in the 50mg AR882 group and 3.4 mg/dL in the 75mg AR882 group, representing reductions of 43.3% and 63.7%, respectively.
- A notable 83% of patients on 75mg AR882 monotherapy achieved serum urate levels below 5 mg/dL.
- Patients on AR882, either alone or in combination with allopurinol, showed better responses in serum urate levels than those on allopurinol alone.
- The DECT findings revealed a 50% reduction in urate crystal volume in the 75mg AR882 group after 6 months, compared to a 25% reduction in the allopurinol group.
- AR882 was generally well-tolerated, with gout flare being the most common adverse event, occurring less frequently in the AR882 groups than in the control group.

This promising data underscores the potential of AR882 as a highly effective treatment for gout, particularly with its sustained efficacy and improved safety profile. The ongoing and upcoming Phase 3 studies aim to further validate these findings, potentially offering a new standard of care for millions of gout sufferers.

In the broader context, gout affects an estimated 13 million people in the U.S., with over 90% of cases resulting from underexcretion of uric acid by the kidneys. This underexcretion leads to elevated serum urate levels and the formation of uric acid crystals in joints and soft tissues, causing painful flare-ups and chronic conditions. Managing serum urate levels is critical in treating and preventing gout.

Arthrosi Therapeutics, based in San Diego, is dedicated to developing AR882, a next-generation URAT1 inhibitor. With promising Phase 2 results, the company is now advancing this potential best-in-class treatment through pivotal Phase 3 trials, aiming to improve the quality of life for gout patients.