After a long, cash-strapped journey, French biotech Abivax has presented top-line data from the twin phase 3 trials of its lead ulcerative colitis candidate.
The oral small molecule, obefazimod, produced a statistically significant pooled remission rate of 16.4% across both trials, largely hitting their primary endpoints, the company announced in a July 22 release.
The trials, ABTECT-1 and ABTECT-2, enrolled a combined 1,275 patients from around the world and tested two daily doses of obefazimod, 50 mg and 25 mg, compared to placebo. The primary endpoint of both trials was the remission rate after eight weeks of treatment as measured by a modified version of the Mayo Score.
In ABTECT-1, both the 50-mg and 25-mg groups had remission rates significantly higher than the placebo group, but, in ABTECT-2, only the 50-mg group saw a significant difference. While further analyses of the data are forthcoming, the company attributed this to the specific patient population that was randomized to the 25-mg group in ABTECT-2.
“The patient population randomized to the 25-milligram dose in ABTECT-2 was the most difficult to treat population across both ABTECT-1 and ABTECT-2,” Fabio Cataldi, M.D., Abivax’s chief medical officer, said on a July 22 investor call. “Based on baseline disease characteristics, we believe this type of patient might require more than eight weeks to achieve clinical remission.”
Obefazimod’s safety profile in the trials was similar to past studies, Abivax said in the release, with no new safety issues. Several patients did experience headaches, which multiple analysts asked the company about on the investor call.
“It was in a small number of people, smaller than we saw with the earlier phase studies, and was not durable,” David Rubin, M.D., a gastroenterologist and director of the Inflammatory Bowel Disease Center at the University of Chicago Medicine, said in response. “It lasts for a short period of time, in the first few days or week of treatment, and goes away.”
A maintenance trial, which will follow patients from both ABTECT-1 and ABTECT-2 until 2030, is currently ongoing. That trial’s primary completion will be in 2026. Abivax is also testing obefazimod in a phase 2 Crohn’s disease trial.
Abivax plans to submit obefazimod to both the FDA and the European Medicines Agency for approval in the second half of 2026, the company said in the release.
Originally under development for HIV, Abivax pivoted obefazimod to colitis after midstage HIV trial results proved lackluster. The company posted positive phase 2 colitis data in 2018 before entering a prolonged period of financial struggle.
An investment from Sofinnova in the summer of 2019 extended the biotech’s cash runway out to 2020, with further funds raised from a 2022 European stock sale and a 2023 initial public offering staving off disaster.
The company’s cash runway is, however, set to run out by the fourth quarter of 2025, Chief Financial Officer Didier Blondel said on the call.
“We know we need to raise money in the short term,” Blondel said. “What we want to do at minimum is to be able to fund the company until the maintenance data readout,” which is scheduled for the second quarter of 2026.
Should Abivax stay afloat and get obefazimod across the finish line, it would be a first-in-class option for patients with ulcerative colitis. The molecule is designed to boost the levels of microRNA-124 in the intestines, which helps control inflammation.
“We have no other therapies in our field that treat the disease the way this mechanism is believed to work,” Rubin said on the call. “The way I like to explain it is that rather than targeting specific active inflammation, it shuts it off at the source, resetting a balance of the immune system.”
It would, however, enter a competitive space should it see approval, with a series of major Big Pharmas—including AbbVie, Johnson & Johnson, Takeda, Pfizer and Bristol Myers Squibb—already marketing big-selling immunotherapies for colitis, as well as other indications, and biosimilars also on the market.