Abivax posts ulcerative colitis data, commits to phase 2b

Ulcerative colitis.
Abivax is pushing ABX464 into phase 2b in ulcerative colitis. (KGH/CC-BY-SA-3.0)

Abivax has posted data from a phase 2a trial in patients with moderate-to-severe ulcerative colitis that are refractory to anti-TNF antibodies or corticosteroids. The trial linked ABX464 to improvements in mucosal healing and performance on a symptom scale, leading Abivax to commit to a phase 2b.

ABX464 first entered the clinic as a treatment for HIV, but Abivax’s work on the candidate suggested it may have anti-inflammatory effects. Abivax thinks ABX464 triggers these effects by binding to the cap-binding complex. This is thought to enhance the splicing of two types of RNA, one of which is associated with increased expression of anti-inflammatory microRNA miR124.

Mixed mid-phase data has raised doubts about Abivax’s case for ABX464 in HIV, ramping up the importance of the ulcerative colitis program to the French biotech’s prospects. 

Abivax now has top-line data ready from the first big test of ABX464 in ulcerative colitis. The 32-patient trial was primarily designed to look at the safety of ABX464. But, with ABX464 having already generated safety data in HIV, attention has focused on the early efficacy data generated in the trial and what it may mean for the drug’s prospects.

ABX464 outperformed placebo against a clutch of efficacy endpoints. Half of participants who took ABX464 for eight weeks experienced mucosal healing, as compared to 11% of people in the control arm. Abivax also reported improvements in clinical remission and response.

Abivax sees the data as positive enough to move the drug into phase 2b in the indication, but scope for doubt about the potential of the asset will remain until the results of larger trials are available. The phase 2a tested ABX464 in a small number of patients and the level of competition in ulcerative colitis means it will need strong data to carve out a niche. Abivax will now work to gather that data. 

“Based on these exciting results, Abivax will initiate without any delay a phase 2b dose-ranging study in Europe, with potential input from U.S. KOLs and FDA on study design. Furthermore, these data strongly encourage us to pursue phase 2 clinical trials in other inflammatory indications including Crohn’s disease,” Abivax CEO Hartmut Ehrlich, M.D., said in a statement.