Researchers at the University of Nottingham in the UK are launching a Phase II clinical trial to investigate the potential of hookworm infestation to mitigate the effects of multiple sclerosis (MS).

A team at the university led by Professor David Pritchard has been looking at whether the parasitic worms may have utility in autoimmune conditions such as MS, asthma, allergies or Crohn’s disease. The hypothesis draws on evidence that people infected with hookworms in endemic regions such as Africa seem less susceptible to autoimmune disease.

Led by Professor Pritchard and Professor Cris Constantinescu, the Worms for Immune Regulation in MS (WIRMS) study is part of a three-year, £400,000 project funded by the MS Society. It will explore whether infection with a small and harmless number of hookworms can ease the severity of multiple sclerosis over a 12-month period.

The 25 microscopic worms will be introduced through a patch in the patient’s arm and then flushed out after nine months.

“It sounds like science fiction, but it has been shown in a previous small study that people with MS who also had gut parasite infections had fewer relapses,” commented Jayne Spink, director of research at the MS Society.

“Over time, parasitic worms have evolved to be able to survive an immune system attack and have been linked to a reduction in the severity of the symptoms of MS, which can be debilitating,” she added. The theory is that hookworms may play a role in damping down the immune system, which is overactive in people with MS.

WIRMS is a randomised, placebo-controlled Phase II study in people with relapsing, remitting multiple sclerosis. It will be carried out at multiple centres across the UK.