Efficacy and Safety of RO7790121 Induction Therapy in Moderately to Severely Active Crohn's Disease: A Phase III, Multicenter, Double-Blind, Placebo-Controlled Study

The primary objective of this study is to evaluate the **efficacy** of RO7790121 compared with placebo in inducing response with respect to clinical remission and endoscopic response in patients with moderately to severely active Crohn's Disease. This is clinically relevant as achieving clinical remission and endoscopic response are critical endpoints in the management of Crohn's Disease, potentially leading to improved patient outcomes and quality of life.

Secondary objectives include:

• Evaluating the efficacy of RO7790121 compared with placebo in inducing response with respect to symptomatic remission, endoscopic remission, ulcer-free endoscopy, average daily number of liquid or very soft stools, and average daily abdominal pain scores.
• Assessing the efficacy in terms of Crohn's Disease-related symptoms and health-related quality of life.
• Evaluating efficacy in tumor necrosis factor-like ligand 1A (TL1A) biomarker-defined subgroups.
• Assessing the efficacy in inducing response with respect to clinical and symptomatic response.
• Evaluating efficacy in terms of the participant’s global impressions and general well-being.
• Assessing the safety of RO7790121 compared with placebo.

The clinical trial involves a total of **204 participants** diagnosed with **Moderately to Severely Active Crohn's Disease (CD)**. The study population includes both male and female subjects, aged between 18 and 80 years, with the possibility of including individuals aged 16 to 18 years where local regulations permit. Participants are required to have a body weight of at least 40 kg and a confirmed diagnosis of CD, supported by clinical, endoscopic, and histopathological evidence. The trial population was selected based on specific criteria, including the involvement of the ileum and/or colon, with at least four colonic segments traversable by an endoscope, or three segments for those who have undergone bowel resection. The study does not specify particular lifestyle considerations such as diet or physical activity. The trial includes a vulnerable population, ensuring comprehensive representation of the disease's impact across different demographics.

The clinical trial is a **Phase III**, multicenter, double-blind, placebo-controlled study designed to evaluate the efficacy and safety of induction therapy with RO7790121 in patients with moderately to severely active **Crohn's disease**. The primary objective is to assess the efficacy of RO7790121 compared to placebo in inducing clinical remission and endoscopic response. The trial is expected to commence recruitment on March 1, 2025, and conclude by December 31, 2030. Participants will be randomly assigned to receive either the investigational product or a placebo, ensuring the study's double-blind nature.

The trial will include several study visits, beginning with an inclusion (screening) visit to confirm eligibility based on criteria such as age, body weight, and a confirmed diagnosis of Crohn's disease. Participants must have a centrally-read Simple Endoscopic Score for Crohn's Disease (SES-CD) of ≥ 6 (or ≥ 4 for isolated ileal disease) and a Crohn's Disease Activity Index (CDAI) between 220 and 450. Follow-up visits will be scheduled to monitor the participants' response to the treatment, assess any adverse events, and ensure compliance with the study protocol. The end-of-study visit will evaluate the primary and secondary endpoints, including clinical and endoscopic remission, symptomatic response, and overall change in Crohn's disease symptoms.

Participant involvement is expected to last throughout the trial duration, with specific timelines for each phase of the study. Conditions that may lead to early termination from the study include the occurrence of serious adverse events, adverse events leading to study treatment discontinuation, or any other safety concerns as determined by the study investigators. The trial will adhere to rigorous ethical standards and regulatory requirements to ensure the safety and well-being of all participants.

The clinical trial involves the evaluation of **RO7790121**, an investigational medication developed by F. Hoffmann-La Roche Ltd. This experimental drug is identified by the sponsor product code RO 779-0121/F05-01 and is classified under the European Union medicinal product number PRD11147706. The active substance in RO7790121 is of protein origin, specifically categorized as "Protein - Other." The pharmaceutical form, dosage, route, and frequency of administration for RO7790121 are not explicitly detailed in the provided data. However, it is implied that the medication is intended for induction therapy in patients with moderately to severely active **Crohn's Disease**. The trial aims to assess the efficacy of RO7790121 in inducing clinical remission and endoscopic response.

In addition to the experimental treatment, a **placebo** is utilized as a comparator in this double-blind, placebo-controlled study. The placebo serves as a control to evaluate the true efficacy of RO7790121 by providing a baseline for comparison. The specific details regarding the composition, form, and administration of the placebo are not provided in the data. The study design ensures that neither the participants nor the investigators are aware of the treatment assignments, thereby minimizing bias and enhancing the reliability of the trial outcomes.

The efficacy of the investigational product RO7790121 in patients with moderately to severely active **Crohn's Disease** will be assessed through a series of primary and secondary endpoints. The primary endpoints include clinical remission, defined as a Crohn's Disease Activity Index (CDAI) score of less than 150, and endoscopic response, characterized by a decrease of at least 50% in the Simple Endoscopic Score for Crohn's Disease (SES-CD) from baseline. Secondary endpoints encompass a range of measures, including symptomatic remission, endoscopic remission, ulcer-free endoscopy, and clinical and symptomatic responses among biomarker-defined subgroups. Additional secondary endpoints involve overall changes in Crohn's Disease symptoms, as measured by the Patient Global Impression of Change (PGIC) and the Patient Global Impression of Severity (PGIS), as well as assessments of general well-being and the incidence and severity of adverse events.