Sanofi and Teva Pharmaceutical Industries have reported positive long-term data from the RELIEVE UCCD Phase 2b program showing that their investigational anti-TL1A monoclonal antibody, duvakitug, delivered durable clinical and endoscopic benefits in patients with ulcerative colitis (UC) and Crohn’s disease (CD) who initially responded to induction therapy.
Results from the RELIEVE UCCD long-term extension (LTE) study (NCT05668013) demonstrated that efficacy was maintained over an additional 44 weeks of treatment, reinforcing findings from the earlier 14-week Phase 2b induction study (NCT05499130), where duvakitug achieved clinically meaningful responses compared with placebo. The LTE trial is a double-blind, randomized study evaluating the long-term efficacy, safety and tolerability of duvakitug in UC and CD, the two most common forms of inflammatory bowel disease (IBD).
The LTE enrolled 130 patients who had responded to duvakitug during the induction phase and entered a 44-week maintenance period, bringing total exposure to up to 58 weeks. Participants were re-randomized to receive either 450 mg or 900 mg of subcutaneous duvakitug every four weeks.
At week 44 of maintenance, 58% of UC patients receiving the 900 mg dose and 47% receiving the 450 mg dose achieved the primary endpoint of clinical remission based on the modified Mayo score. In the Crohn’s disease cohort, 55% of patients in the 900 mg arm and 41% in the 450 mg arm achieved the primary endpoint of endoscopic response as measured by the Simple Endoscopic Score for Crohn’s Disease. Across both indications, additional efficacy endpoints showed consistent benefit, supporting the durability of response over nearly one year of therapy.
Both dose regimens were reported to be well tolerated. The most common adverse events, occurring in at least 5% of patients across pooled doses, included upper respiratory tract infection, nasopharyngitis, Crohn’s disease and hypertension. The safety profile was consistent with that observed in the induction study, and no new safety concerns were identified. Detailed data from the LTE study are expected to be presented at a forthcoming medical meeting.
Duvakitug targets TL1A, a cytokine implicated in intestinal inflammation and fibrosis, positioning it as a potential disease-modifying therapy in IBD. The Phase 2b findings support the advancement of duvakitug into ongoing Phase 3 programs in both ulcerative colitis and Crohn’s disease.
Inflammatory bowel disease is a chronic autoimmune condition marked by persistent inflammation of the gastrointestinal tract. Globally, an estimated 4.9 million people are living with IBD, and incidence is increasing in several regions. Ulcerative colitis and Crohn’s disease are characterized by cycles of relapse and remission, with common symptoms including persistent diarrhea, rectal bleeding, abdominal pain, weight loss and fatigue. Prolonged inflammation can lead to structural damage such as fibrosis, which involves excessive scar tissue formation in the intestinal wall and may result in narrowing or obstruction. There is currently no cure for IBD, and treatment strategies focus on inducing and maintaining remission while preventing disease flares.
The RELIEVE UCCD Phase 2b program consists of a 14-week randomized, double-blind, dose-ranging induction study and an ongoing long-term extension. The induction trial employed a basket study design that enrolled adults with moderate-to-severe UC or CD and evaluated efficacy, safety, pharmacokinetics and tolerability of duvakitug. It is the first randomized, blinded, placebo-controlled Phase 2 study to investigate the role of TL1A inhibition in Crohn’s disease. Patients who completed the induction phase and achieved response were eligible to enter the 44-week double-blind maintenance period, with the option to continue into an open-label extension after completing maintenance. The program includes study sites across the United States, Europe, Israel and Asia.
The long-term maintenance results further strengthen the clinical profile of duvakitug as a potential new therapeutic option targeting TL1A in inflammatory bowel disease, with late-stage development now underway.
