Anti-tumour necrosis factor discontinuation in inflammatory bowel disease patients in remission: study protocol of a prospective, multicentre, randomized clinical trial

Background: Patients with inflammatory bowel disease who achieve remission with anti-tumour necrosis factor (anti-TNF) drugs may have treatment withdrawn due to safety concerns and cost considerations, but there is a lack of prospective, controlled data investigating this strategy. The primary study aim is to compare the rates of clinical remission at 1?year in patients who discontinue anti-TNF treatment versus those who continue treatment. Methods: This is an ongoing, prospective, double-blind, multicentre, randomized, placebo-controlled study in patients with Crohn?s disease or ulcerative colitis who have achieved clinical remission for ?6?months with an anti-TNF treatment and an immunosuppressant. Patients are being randomized 1:1 to discontinue anti-TNF therapy or continue therapy. Randomization stratifies patients by the type of inflammatory bowel disease and drug (infliximab versus adalimumab) at study inclusion. The primary endpoint of the study is sustained clinical remission at 1?year. Other endpoints include endoscopic and radiological activity, patient-reported outcomes (quality of life, work productivity), safety and predictive factors for relapse. The required sample size is 194 patients. In addition to the main analysis (discontinuation versus continuation), subanalyses will include stratification by type of inflammatory bowel disease, phenotype and previous treatment. Biological samples will be obtained to identify factors predictive of relapse after treatment withdrawal. Results: Enrolment began in 2016, and the study is expected to end in 2020. Conclusions: This study will contribute prospective, controlled data on outcomes and predictors of relapse in patients with inflammatory bowel disease after withdrawal of anti-TNF agents following achievement of clinical remission. Clinical trial reference number: EudraCT 2015-001410-1

Long-term Efficacy and Safety of Stem Cell Therapy (Cx601) for Complex Perianal Fistulas in Patients With Crohn's Disease

Background & Aims: Therapies for perianal fistulas in patients with Crohn's disease are often ineffective in producing long-term healing. We performed a randomized placebo-controlled trial to determine the long-term efficacy and safety of a single local administration of allogeneic expanded adipose-derived stem cells (Cx601) in patients with Crohn's disease and perianal fistulas. Methods: We performed a double-blind study at 49 hospitals in Europe and Israel, comprising 212 patients with Crohn's disease and treatment-refractory, draining, complex perianal fistulas. Patients were randomly assigned (1:1) to groups given a single local injection of 120 million Cx601 cells or placebo (control), in addition to the standard of care. Efficacy endpoints evaluated in the modified intention-to-treat population (randomly assigned, treated, and with 1 or more post-baseline efficacy assessment) at week 52 included combined remission (closure of all treated external openings draining at baseline with absence of collections >2 cm, confirmed by magnetic resonance imaging) and clinical remission (absence of draining fistulas). Results: The study's primary endpoint, at week 24, was previously reported (combined remission in 51.5% of patients given Cx601 vs 35.6% of controls, for a difference of 15.8 percentage points; 97.5% confidence interval [CI] 0.5–31.2; P =.021). At week 52, a significantly greater proportion of patients given Cx601 achieved combined remission (56.3%) vs controls (38.6%) (a difference of 17.7 percentage points; 95% CI 4.2–31.2; P =.010), and clinical remission (59.2% vs 41.6% of controls, for a difference of 17.6 percentage points; 95% CI 4.1–31.1; P =.013). Safety was maintained throughout week 52; adverse events occurred in 76.7% of patients in the Cx601 group and 72.5% of patients in the control group. Conclusion: In a phase 3 trial of patients with Crohn's disease and treatment-refractory complex perianal fistulas, we found Cx601 to be safe and effective in closing external openings, compared with placebo, after 1 year. ClinicalTrials.gov no: NCT01541579

Long-term Efficacy and Safety of Stem Cell Therapy (Cx601) for Complex Perianal Fistulas in Patients With Crohn's Disease

BACKGROUND & AIMS: Therapies for perianal fistulas in patients with Crohn's disease are often ineffective in producing long-term healing. We performed a randomized placebo-controlled trial to determine the long-term efficacy and safety of a single local administration of allogeneic expanded adipose-derived stem cells (Cx601) in patients with Crohn's disease and perianal fistulas. METHODS: We performed a double-blind study at 49 hospitals in Europe and Israel, comprising 212 patients with Crohn's disease and treatment-refractory, draining, complex perianal fistulas. Patients were randomly assigned (1:1) to groups given a single local injection of 120 million Cx601 cells or placebo (control), in addition to the standard of care. Efficacy endpoints evaluated in the modified intention-to-treat population (randomly assigned, treated, and with 1 or more post-baseline efficacy assessment) at week 52 included combined remission (closure of all treated external openings draining at baseline with absence of collections >2 cm, confirmed by magnetic resonance imaging) and clinical remission (absence of draining fistulas). RESULTS: The study's primary endpoint, at week 24, was previously reported (combined remission in 51.5% of patients given Cx601 vs 35.6% of controls, for a difference of 15.8 percentage points; 97.5% confidence interval [CI] 0.5-31.2; P = .021). At week 52, a significantly greater proportion of patients given Cx601 achieved combined remission (56.3%) vs controls (38.6%) (a difference of 17.7 percentage points; 95% CI 4.2-31.2; P = .010), and clinical remission (59.2% vs 41.6% of controls, for a difference of 17.6 percentage points; 95% CI 4.1-31.1; P = .013). Safety was maintained throughout week 52; adverse events occurred in 76.7% of patients in the Cx601 group and 72.5% of patients in the control group. CONCLUSION: In a phase 3 trial of patients with Crohn's disease and treatment-refractory complex perianal fistulas, we found Cx601 to be safe and effective in closing external openings, compared with placebo, after 1 year. ClinicalTrials.gov no: NCT01541579