On February 22, 2025, researchers from Sanofi and Teva took the stage at ECCO 2025 in Berlin to share encouraging results from the RELIEVE UCCD trial, a randomized 14-week phase 2b study testing duvakitug in moderate-to-severe ulcerative colitis and Crohn’s disease. This is the first randomized and placebo controlled study targeting the TL1A pathway in these two most common forms of inflammatory bowel disease.

In ulcerative colitis the data showed clear benefit. At week 14, 36 percent of patients receiving 450 milligrams of duvakitug achieved clinical remission compared to 20 percent with placebo. For those on the higher 900 milligram dose remission rose to 48 percent. In other words the higher dose offered a placebo-adjusted benefit of 27 percent.

What stands out is that duvakitug showed similar advantages across patients regardless of their prior exposure to advanced therapies. Among those who had not been treated with advanced therapies before, nearly 53 percent reached remission on the higher dose, compared with 20 percent of placebo patients. Patients who had previously used advanced therapies still saw substantial improvements with duvakitug.

Beyond remission, other markers also improved. Clinical response rate rose above 70 percent even at the lower dose and a striking 81 percent at the higher dose, compared with just 52 percent on placebo. Endoscopic improvement and mucosal healing also favored duvakitug, confirming benefits across several biological layers.

In the Crohn’s disease arm the results were equally encouraging. Endoscopic response at week 14 was seen in 48 percent of patients on the higher dose compared to just 13 percent with placebo. That represents a placebo-adjusted improvement of 35 percent. Even at the lower dose the response rate of 26 percent showed a meaningful benefit over placebo.

Prior treatment history did not dull the effect. Both treatment experienced and treatment naïve subgroups saw gains. Furthermore clinical remission and response rates based on CDAI and PRO2 measures also leaned in favor of duvakitug.

Safety is always a concern, and duvakitug did not raise any red flags. The treatment was generally well tolerated with no noticeable pattern of dose dependent side effects, serious adverse events or treatment discontinuations reported.

Dr Walter Reinisch from the Medical University of Vienna, lead investigator on the ulcerative colitis cohort, remarked that duvakitug’s ability to reduce inflammation so effectively may mark a genuine turning point for patients who have faced repeated cycles of relapse and remission. For the Crohn’s disease cohort, Dr Vipul Jairath from Western University expressed optimism that the strong endoscopic response seen in the trial might translate into a much needed new therapeutic option.

These data pave the way toward a phase 3 development program due to launch in the second half of 2025, according to Sanofi and Teva. This stage will be crucial to confirm duvakitug’s clinical potential and build toward regulatory filings.

Beyond science the collaboration between the two companies merits mention. Sanofi and Teva are co-developing and co-commercializing duvakitug. Sanofi is leading the phase 3 program, and will handle commercialization in North America, Japan and some parts of Asia. Teva will take charge in Europe, Israel and select other markets. The companies share both the development costs and profits.

If subsequent trials uphold these phase 2b findings, duvakitug could become a best-in-class treatment targeting TL1A, offering hope to patients whose disease has not been controlled by existing therapies and addressing an important unmet medical need.