Treatment with Abivax‘s ABX464 showed continuing effectiveness in ulcerative colitis patients, according to nine-month data of a maintenance clinical trial.
The company is now recruiting people with moderate-to-severe ulcerative colitis for its Phase 2b trial (NCT03760003) of ABX464, to be conducted in up to 150 sites in more than 15 countries.
ABX464 is a small molecule taken once daily by mouth. It works by targeting a group of proteins called the Cap Binding Complex, a novel mechanism of action for anti-inflammatory therapies. This leads to a series of events within cells, namely the production of microRNA-124 (miR-124). This molecule reduces the production of inflammatory signals, thus “putting the brakes” on inflammation.
The treatment was tested in a Phase 2a clinical trial (NCT03093259) in which 32 participants were randomly selected to receive either 50 milligrams of ABX464 or a placebo for eight weeks. A total 29 patients completed the trial, and 35% of those given ABX464 were in clinical remission at the study’s end.
After this study, all participants had the option to continue in an open-label extension of the study — that is, a continuation in which all patients are given the treatment, without placebos — called ABX464-102 (NCT03368118).
At the Digestive Disease Week (DDW) 2019 conference, held recently in San Diego, data was presented for 19 patients. The seven who were in clinical remission at the end of the the trial remained in that status through the nine months of the extension study.
Among the 12 patients not in clinical remission at the end of the initial study, 11 were reported to have “at least a clinical response” by the end of the extension study. None of the 12 were reported to be in remission by the extension study’s conclusion.
Additionally, levels of fecal calprotectin, a marker of inflammatory bowel disease, decreased from a median of 1044 micrograms per gram (µg/g) at the beginning of the initial induction study to a median of 24 µg/g at nine months. This is well within the range of what is considered healthy (<50µg/g), the researchers said.
“The safety and durability of the effect at this nine months interim analyses of the open label maintenance study further confirm our hypothesis that ABX464’s novel mechanism of action would result in potent and durable anti-inflammatory responses in these patients,” Jean-Marc Steens, MD, Abivax’s chief medical officer, said in a press release.
No adverse events were reported.
The researchers said only two-thirds of people with ulcerative colitis respond to currently available treatments, including biologics. Half of those seeing an effect stop responding after six to 12 months.
“[T]here is a large unmet need for effective ulcerative colitis therapies. This is a debilitating disease that greatly affects patients’ quality of life and requires expensive and cumbersome therapies,” said William Sandborn, MD, director of the Inflammatory Bowel Disease Center at University of California San Diego Health, and chief of the division of gastroenterology at UC San Diego School of Medicine.
“The innovative mechanism of action of ABX464 and data from this trial represent a promising new potential approach to the treatment of ulcerative colitis that could deliver these patients an easily administered, oral, long-term therapeutic management option,” Sandborn said.
The extension study has already been approved to continue for another year, and Abivax is actively testing ABX464 in other inflammatory diseases.