Efficacy and Safety of Duvakitug for Maintenance Therapy in Participants with Moderately to Severely Active Crohn’s Disease: A Phase 3, Randomized, Placebo-Controlled Study

The primary objective of this study is to evaluate the efficacy of duvakitug as maintenance therapy compared to placebo in participants with moderately to severely active Crohn's disease (5).

Secondary objectives include:

• Assessment of efficacy using multiple measures of disease activity.
• Evaluation of pharmacokinetics (6) and immunogenicity.
• Assessment of safety (4) of duvakitug as maintenance therapy compared to placebo.
• Evaluation of the safety of long-term administration of duvakitug.

This study involves 465 patients diagnosed with Crohn's disease. The study population includes both male and female individuals. Participants are within an age range typically spanning from adolescents to older adults, specifically those aged 18 to 80 years, though individuals aged 16 to <18 years meeting specific developmental criteria may be included where locally permissible. Eligible subjects must have achieved a clinical response and completed an endoscopy during a preceding study phase. The cohort includes individuals with immune system diseases and encompasses vulnerable populations.

This is a multicenter, multinational, randomized, double-blind, placebo-controlled, Phase 3 maintenance study designed to evaluate the efficacy and safety of duvakitug in participants with moderately to severely active Crohn’s disease. The investigation involves the administration of duvakitug or a matched placebo via subcutaneous injection. The primary objective is to assess the proportion of participants achieving clinical remission and endoscopic response at Week 40. Participants must have achieved a clinical response and completed endoscopy at the conclusion of the STARSCAPE-1 study to be eligible for the pivotal maintenance sub-study. An open-label extension sub-study is also available for those completing the pivotal maintenance phase or the TV48574-IMM-20038 study. The total estimated duration of the trial spans from May 2026 to July 2034. Secondary endpoints include measures of ulcer-free endoscopy, corticosteroids free remission, and the incidence of treatment-emergent adverse events.

The experimental medication consists of duvakitug, provided as a solution for injection. This substance is administered via subcutaneous injection to participants with moderately to severely active Crohn’s disease.

The comparator treatment is a matched placebo designed to be identical to the test product for the purposes of maintaining the double-blind design of the study.

The efficacy of duvakitug in participants with moderately to severely active Crohn’s disease is evaluated through several primary and secondary endpoints at Week 40. The co-primary endpoints for regulatory assessment include the proportion of participants achieving clinical remission as measured by the Crohn's Disease Activity Index (CDAI) or the PRO-2, alongside the proportion of participants achieving endoscopic response via the Simple Endoscopic Score for Crohn's Disease (SES-CD).

Secondary efficacy parameters include:

• Proportion of participants achieving CDAI clinical response or SES-CD endoscopic remission at Week 40.
• Combined achievement of clinical remission and endoscopic remission using CDAI or PRO-2 scales.
• Proportion of participants achieving corticosteroid-free clinical remission per CDAI or PRO-2.
• Proportion of participants achieving ulcer-free endoscopy in the subset with ulcers at baseline.
• Maintenance of clinical remission per CDAI or PRO-2 in participants who were in remission at Week 0.
• Change from baseline in the PROMIS-Fatigue Short Form 7a T-score and the Inflammatory Bowel Disease Questionnaire (IBDQ) total score.
• Proportion of participants with no bowel urgency as measured by the Numerical Rating Scale (NRS).
• Incidence of disease-related hospitalization.
• Serum concentrations of duvakitug measured over time.