Socio-Medical Studies of Individuals Self-Treating with Helminths Suggest That Most Clinical Trials Assessing Helminth Therapy May Be Designed to Fail

Abstract

The virtually complete loss of intestinal worms, known as helminths, from Western society has resulted in elimination of a range of helminth-induced morbidities. Unfortunately, that loss has also led to inflammation-associated deficiencies in immune function, ultimately contributing to widespread pandemics of allergies, autoimmunity, and neuropsychiatric disorders. Several socio-medical studies have examined the effects of intentional reworming, or self-treatment with helminths, on a variety of inflammation-related disorders. In this study, the latest results from ongoing socio-medical studies are described. The results point toward two important factors that appear to be overlooked in some if not most clinical trials. Specifically, (a) the method of preparation of the helminth can have a profound effect on its therapeutic efficacy, and (b) variation between individuals in the effective therapeutic dosage apparently covers a 10-fold range, regardless of the helminth used. These results highlight current limits in our understanding of the biology of both hosts and helminths, and suggest that information from self-treatment may be critical in moving the field forward into mainstream medicine.

Authors’ response to Graham Rook’s commentary

“…Contrary to the assertion by Rook, results from these systematic studies are not anecdotal in nature, except on occasion where appropriate for the study design. These studies conclusively affirm results from Correale’s studies, providing clear explanations for differences between the impressive results of natural exposures reported by Correale and the negative results of several clinical trials [ 2 ]. These issues were reviewed in our original manuscript, and hence are not recounted here.…”

Between a hygiene rock and a hygienic hard place

“…Further, lack of interest in the field is likely encouraged by lackluster results of clinical studies that, although time consuming and costly, were probably not designed appropriately to evaluate the use of helminths as a therapeutic agent. For example, two primary concerns with prior studies are that (i) they do not take into account large variations in the amount of exposure to helminths necessary for beneficial effects in humans and (ii) they do not take into account potential nuances in the production and storage of living organisms that might affect their clinical efficacy [27,75]. A further complicating problem is that the selection of helminth species for use in clinical trials thus far has been haphazard, dictated by convenience rather than by a systematic search for a benign helminth that effectively regulates immune function [76].…”

“…Indeed, benign helminths are already available which can be evaluated for their potential to reverse the effects of biota alteration [30,68,76,79]. Unfortunately, clinical trials with 'helminth therapy' to date have been problematic, not taking into account nuances with the cultivation of helminths, selection of helminths with the best benefit-to-risk ratios and the wide range of individual-to-individual variation in the effective treatment regimens [27,75]. Action is urgently needed given the importance of immune function, not only for immunological tolerance to our own bodies and harmless environmental antigens, but also for effective, self-preserving responses against current and future pathogens.…”