Consumption of gluten with gluten-degrading enzyme by celiac patients: A pilot-study

AIM:To assesses the safety and efficacy of Aspergillus niger prolyl endoprotease(AN-PEP)to mitigate the im-munogenic effects of gluten in celiac patients.METHODS:Patients with initial diagnosis of celiac disease as confirmed by positive serology with subtotal or total villous atrophy on duodenal biopsies who adhere to a strict gluten-free diet(GFD)resulting in normalised antibodies and mucosal healing classified as Marsh 0 orⅠwere included.In a randomised double-blind placebo-controlled pilot study,patients consumed toast(approximately 7 g/d gluten)with AN-PEP for 2 wk(safety phase).After a 2-wk washout period with adherence of the usual GFD,14 patients were randomised to gluten intake with either AN-PEP or placebo for 2 wk(efficacy phase).Measurements at baseline included complaints,quality-of-life,serum antibodies,immunophenotyping of T-cells and duodenal mucosa immunohistology.Furthermore,serum and quality of life questionnaires were collected during and after the safety,washout and efficacy phase.Duodenal biopsies were collected after the safety phase and after the efficacy phase.A change in histological evaluation according to the modified Marsh classification was the primary endpoint.RESULTS:In total,16 adults were enrolled in the study.No serious adverse events occurred during the trial and no patients withdrew during the trial.The mean score for the gastrointestinal subcategory of the celiac disease quality(CDQ)was relatively high throughout the study,indicating that AN-PEP was well tolerated.In the efficacy phase,the CDQ scores of patients consuming gluten with placebo or gluten with AN-PEP did not significantly deteriorate and moreover no differences between the groups were observed.During the efficacy phase,neither the placebo nor the AN-PEP group developed significant antibody titers.The IgA-EM concentrations remained negative in both groups.Two patients were excluded from entering the efficacy phase as their mucosa showed an increase oftwo Marsh steps after the safety phase,yet with undetectable s