Atom Bioscience has revealed positive results from its China Phase IIa clinical trial of ABP-671, its URAT1 inhibitor for chronic gout.
The randomised, double-blind, placebo-controlled trial enrolled 54 patients with gout or across six cohorts, with seven randomised to ABP-671 and two to placebo per cohort.
“The results from our Phase IIa clinical trial in China are consistent with the findings from our Phase IIa trial in Australia, indicating that ABP-671 can effectively reduce uric acid levels significantly and safely compared to currently marketed gout drugs, which have been associated with serious adverse side effects,” said Dr William Shi, CEO and Chairman of Atom Bioscience.
“The consistency of these positive results from our back-to-back clinical trials is encouraging, and we look forward to advancing ABP-671 into pivotal trials in the US and other countries later this year.”
The study successfully reached its main endpoints. At a dose of 1mg ABP-671 once daily (QD), 86% of patients reached serum uric acid (sUA) levels below 6mg/dL.
Furthermore, 100% of patients achieved sUA levels below 6mg/dL in multiple higher tested doses. At doses of 6mg and 12mg ABP-671 QD, 100% of patients saw their sUA levels drop below 5mg/dL, and 57% and 100% respectively achieved sUA levels below 4mg/dL.
The Phase IIa Australian study also met its primary objective of lowering sUA levels to below 6mg/dL and was well tolerated.
Much higher doses needed
The American College of Rheumatology recommends sUA levels below 6mg/dL for the prevention of gout flares and long-term joint damage. The British Society of Rheumatology and the European Alliance of Associations for Rheumatology recommend a target sUA level of < 5mg/dL for tophaceous gout.
Current medications in the gout therapeutics market require much higher doses to control chronic gout and are generally accompanied by serious side effects, such as severe hepatotoxicity, nephrotoxicity, higher risk of sudden death, heart disease, or gastrointestinal discomfort.
ABP-671 is a small molecule inhibitor of the urate transporter 1 (URAT1) protein, which is involved in the reabsorption of uric acid by the kidneys. In gout patients, ABP-671 reduces the reabsorption of uric acid, increasing its excretion in urine.