Helminths and MS: A Recent Review Paper

This past September, an article[i] was published about using helminths as a treatment for multiple sclerosis.  It has several tidbits I found particularly interesting.  Here are 5 highlights:

1. Research was done in the French West Indies over 20 years, which showed a marked increase in the incidence of MS as the population was treated for helminth infection.  In fact, in other research, scientists noted that when 10% or more of a given population had Trichuris trichuria (human whipworm), MS rates significantly go down.
2. A great sentence – one which I wish would become a more prevailing understanding: “Moreover, infections are primarily asymptomatic and mortality is rare.   It is suggested that this phenomenon has occurred due to the long evolutionary coadaptation between these parasites and man.”  Considering that all of mankind had helminths for all of our evolutionary history up until 100 years ago or so, this makes sense.  Were we sick or dead, we’d not have lasted long as a species!
3. There have been 12 animal studies on the effects of helminths on autoimmune encephalomyelitis (EAE), which mimics the key features of MS, like paralysis and demyelination. 11 of these showed that helminths protected the animals from developing EAE.  One thing that became apparent during these studies is that not every helminth worked equally well.
4. A 2007 study of MS patients with helminths showed that over 4.5 years, these individuals had a dramatic and sustained reduction in MRI changes. A follow up study done over the next 5-7 years showed that once helminths were cleared (via anti-helminth drugs), patients rapidly declined to a level similar to those who were uninfected.
5. “To date, all phase 1 studies have shown that treatment with the helminths is safe….Over the last three years, two double-blinded, placebo-controlled phase 2 trials have been undertaken. One of these is still ongoing (HINT2) and although the second (WIRMS) is completed; the results have not yet been published. These studies will provide a comprehensive and meaningful outcome and determine the future of live worm therapeutics.”

Rest assured, I will write about the results of these studies as soon as they become available.

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[i] Dixit, A, Tanaka, A, Greer, J, Donnelly, S. Novel Therapeutics for Multiple Sclerosis Designed by Parasitic Worms.  International Journal of Molecular Sciences. 2017, 18(10), 2141; doi:10.3390/ijms18102141