Scientific Abstract

Proposal No. IBD-0184
Principal Investigator:   Paul J. Fortun, BM BCh
Applicant Organization:  University of Nottingham (United Kingdom)
Project Title: Hookworm infestation as therapy in Crohn's disease
Period of Award:  August 14, 2006 – August 13, 2008

We propose a controlled clinical trial of the effect of hookworm infestation on disease activity in patients with Crohn’s disease.  Suitable patients will be those with a Crohn’s Disease Activity Index between 220 and 450.  They will be randomized to receive a single dose of 10 Necator americanus hookworm larvae or placebo.  The active treatment and placebo will be administered under a sticking plaster applied for 24 hours.  The placebo plaster will be impregnated with histamine to replicate the itch sometimes associated with hookworm and help to maintain blinding.  Patients will be seen every three weeks for 12 weeks, and at 24 weeks.  Analysis will be based upon comparison in the Crohn’s disease Activity Index at week 12 in those with and without active treatment.  This will be supplemented by a number of secondary measures including other inflammatory indices, patient global assessment, quality of life and detailed immunological studies of underlying mechanistic changes.

By studying 56 patients, the study will have 90% power to detect sufficient difference of 98 and 80% power to detect a difference of 85 in the CDAI scale. The successful study would pave the way for a larger clinical trial of hookworm infestation and ultimately the discovery of a therapeutic product derived from hookworm. The study will also provide important immunological data for interpretation of the mechanisms underpinning the effect of hookworms on Crohn’s disease.