Abivax has recruited the first patient for a Phase IIb clinical trial assessing oral, once-daily ABX464 to treat moderate to severe active ulcerative colitis (UC).

ABX464 is an anti-inflammatory molecule that binds to the cap-binding complex (CBC) and boosts its function in cellular RNA biogenesis.

The drug candidate is said to improve the selective splicing of a single long non-coding RNA to allow the production of an anti-inflammatory microRNA called miR-124.

miR-124 downregulates pro-inflammatory cytokines and chemokines to block inflammation.

According to previous data, ABX464 led to a seven-to-ten times rise in miR124 levels in the peripheral blood mononuclear cells (PBMCs) of healthy people and in colorectal biopsies of patients with UC.

The randomised, double-blind, placebo-controlled, dose-ranging Phase IIb study will compare 25mg/day, 50mg/day and 100mg/day doses of ABX464 with placebo in a total of 232 patients.

It comprises an induction phase of 16 weeks and a subsequent open-label maintenance study.

The primary endpoint of the trial is a decrease in the modified Mayo Score at week eight, while secondary endpoints include clinical remission, endoscopic improvement, and biomarker faecal calprotectin.

Abivax CEO Hartmut Ehrlich said: “The objectives of this Phase IIb study are to confirm that ABX464’s novel mechanism of action will result in potent and durable anti-inflammatory responses in a much larger patient population, and to define the optimal dose for subsequent Phase III testing.

“We look forward to developing and potentially marketing ABX464 as a well-tolerated and highly efficacious oral treatment for the large population of ulcerative colitis patients who currently have only limited treatment options.”

The study has secured approvals in nine countries and is set to be performed at up to 150 sites across Europe and Canada.

Top-line data from the induction phase of the trial is expected to be reported by the end of next year.