Prevalence of Anal Fistulas in Europe: Systematic Literature Reviews and Population-Based Database Analysis.

INTRODUCTION: Despite the fact that perianal fistulas are associated with significant morbidity and impaired quality of life, their prevalence in Europe is unknown. The aim of this study was to estimate the prevalence of perianal fistulas in Europe, overall and according to etiology. METHODS: Two independent literature reviews were performed using different search strategies to maximize the identification of potentially relevant studies. Data from relevant articles were used to estimate the prevalence of perianal fistulas in Europe. The robustness of the estimate was evaluated using data from a large population-based database from the UK. RESULTS: A total of 26 studies provided epidemiological data on perianal fistulas, of which 16 provided suitable data to estimate the prevalence. Estimations using these data yielded a total prevalence of 1.69 per 10,000 population. Cryptoglandular infection and Crohn's disease (CD) were the predominant etiologies, with prevalence rates at 0.86 and 0.76 per 10,000 population, respectively. Comparison of prevalence data from the UK population-based database with the European population resulted in a standardized prevalence estimate of all perianal fistulas of 1.83 per 10,000 population, confirming the robustness of the literature-based estimate. CONCLUSION: Although in terms of incidence cryptoglandular fistulas were clearly predominant, the prevalence of fistulas in CD and cryptoglandular infection appeared more balanced. This is due to the longer duration and higher frequency of relapses of fistulas in CD. The estimated prevalence implies that perianal fistulas meet the criteria to be considered as a rare condition in Europe (prevalence less than 5 per 10,000 population). FUNDING: This study was funded by Takeda Pharmaceutical U.S.A., Inc. and TiGenix SAU.

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.

Pharmacokinetic assessment of a fast-release orodispersible tramadol tablet compared to a conventional tramadol capsule.

The purpose of this clinical trial was to compare the pharmacokinetics of a recently developed fast-release orodispersible tramadol tablet (CAS 27203-92-5, Zamadol Melt) to that of a conventional tramadol capsule. This new formulation, once placed into the mouth, disintegrates rapidly in contact with the saliva. Therefore, when the saliva is swallowed, the drug reaches the gastrointestinal tract. In an open, randomised, two-period, crossover study performed in 20 healthy volunteers, the orodispersible tramadol tablet and a conventional tramadol capsule were administered. Even although the galenics of both products are far different, statistical analysis of pharmacokinetic parameters allows concluding bioequivalence, not only for the parent molecule (tramadol), but also for its active metabolite O-desmethyl tramadol. This orally dispersible formulation, being bioequivalent to the standard capsules so far used, has the practical advantage that it can be taken without liquids. This facilitates an early treatment of emergent pain, irrespective of the place or situation where it may arise.