Safety and efficacy of helminth treatment in relapsing-remitting multiple sclerosis: Results of the HINT 2 clinical trial

Abstract

Background: The hygiene hypothesis suggests that microbial replacement may be therapeutic in allergic and autoimmune diseases. Nevertheless, the results of helminth treatment, including in multiple sclerosis (MS), have been inconclusive. Objective: To assess safety and brain magnetic resonance imaging (MRI) activity in subjects with relapsing-remitting multiple sclerosis (RRMS) during oral administration of ova from the porcine whipworm, Trichuris suis (TSO). Methods: A total of 16 disease-modifying treatment (DMT) naive RRMS subjects were studied in a baseline versus treatment (BVT) controlled prospective study. MRI scans were performed during 5 months of screening-observation, 10 months of treatment, and 4 months of post-treatment surveillance. Results: No serious symptoms or adverse events occurred during treatment. For the cohort, there was a trend consistent with a 35% diminution in active lesions when observation MRIs were compared to treatment MRIs (p = 0.08), and at the level of individuals, 12 of 16 subjects improved during TSO treatment. T regulatory lymphocytes were increased during TSO treatment. Conclusion: TSO is safe in RRMS subjects. Potentially favorable MRI outcomes and immunoregulatory changes were observed during TSO treatment; however, the magnitude of these effects was modest, and there was considerable variation among the responses of individual subjects.