Arthrosi Therapeutics, Inc., invested and incubated by Viva BioInnovator (VBI), is a clinical-stage biotechnology company developing treatments for gout that dissolve uric acid crystals and prevent joint damage. Recently they announced new clinical data from its phase 2 AR882-203 study in patients with tophaceous gout. The late-breaking data has been presented as an oral presentation at the American College of Rheumatology (ACR) Convergence 2023 meeting, held in San Diego, CA on November 10-15, 2023.

In the late-breaking oral presentation, Dr. Robert Keenan MD, MPH, MBA, Chief Medical Officer of Arthrosi, has unveiled compelling new clinical findings from the phase 2 trial. The data showcases the strong efficacy of AR882, demonstrating significant reduction of tophi, crystal burden, flare rates, in addition to lowering sUA among patients suffering from tophaceous gout.

In the intent-to-treat population, AR882 demonstrated a significant decrease in sUA at 3 months. Notably, in the 75 mg AR882 group, 86% and 64% of patients achieved sUA levels below 6 and 5 mg/dL, respectively, compared to 77% and 69% in the 50 mg AR882 + allopurinol group and 46% and 23% in the allopurinol group.

Significantly higher response rates in total crystal volume reduction were observed by Dual Energy Computed Tomography (DECT) imaging. Specifically, the AR882 75 mg group showed a notable reduction in total urate crystal volume (-8.3 cm3, baseline 15.6 cm3) compared to allopurinol (-1.2 cm3, baseline 11.5 cm3) or combination (-0.9 cm3, baseline 4.7 cm3) on DECT at Month 6. (Figure 1 illustrates DECT images of one severe gout patient’s crystal burden at baseline (left) and at 6 months following QD treatment of 75 mg AR882).

Consistent with DECT imaging, AR882 75 mg demonstrated significantly higher response rate of at least 1 complete target tophi dissolution by caliper measurement than allopurinol 300 mg, or allopurinol 300 mg in combination with AR882 50 mg. These clinical findings, highlighted via both DECT and caliper, underscore the effectiveness of AR882 in reducing urate crystal burden, further substantiating its potential as a groundbreaking therapeutic solution for patients.

“We are excited to share new data from our phase 2 tophaceous gout study at ACR highlighting its potential to significantly improve the standard of care for a broad range of patients living with gout,” said Arthrosi's Chief Executive Officer Litain Yeh, PhD. “Importantly, in the case of patients with tophaceous gout, there remains a high unmet need for a safe, efficacious and convenient therapy to reduce sUA levels below 5 mg/dL, which has been established in the literature as necessary to quickly resolve and reduce debilitating symptoms associated with tophi and flares.”

About Arthrosi

Arthrosi Therapeutics, Inc., headquartered in San Diego, CA, was established in 2018. The company’s goal is to develop potential treatments aimed at uric acid levels and minimizing joint damage for gout patients. Arthrosi anticipates initiating pivotal phase 3 program in early 2024.