Relapsing MS: hookworm treatment misses the mark in WIRMS trial

  • Tanasescu R & al.
  • JAMA Neurol
  • 15 Jun 2020

  • curated by Susan London
  • Clinical Essentials
Access to the full content of this site is available only to registered healthcare professionals. Access to the full content of this site is available only to registered healthcare professionals.

Takeaway

  • Among patients with relapsing multiple sclerosis (MS), hookworm treatment was safe but did not affect lesion findings on MRI.

Why this matters

  • Approaches that modify the innate immune response are attractive.
  • Editorial: Despite safety, efficacy "appears modest, making it unlikely to be a sufficient stand-alone treatment for MS."
    • Also notes concerns about helminths as add-on, "given the potential increase in infection rates when used with concomitant immunomodulating medications.”

Key results

  • During months 3 to 9 postinfection, no significant difference was detected between hookworm and placebo groups in total number of new T2 lesions, newly enhancing T1-weighted lesions, or T2 enlarging lesions:
    • Median: 0 vs 1.5.
    • Mean: 4.1 vs 3.8.
  • Hookworm group:
    • Somewhat less likely to have any MRI activity (OR, 0.33; 95% CI, 0.11-1.02).
    • Higher percentage of CD4+CD25highCD127neg T cells in peripheral blood (4.4% vs 3.9%; P=.01).
    • Lower relapse rate per patient (14.3% vs 30.6%).
  • No withdrawals for adverse effects.
  • Only differing adverse event was more application-site skin discomfort in hookworm group (82.86% vs 27.78%).

Study design

  • UK single-center phase 2 randomized controlled trial among 71 adults with relapsing MS not receiving disease-modifying treatment (WIRMS trial).
  • Randomization: single transcutaneous administration of live, infective hookworms (25 Necator americanus larvae) vs placebo.
  • Main outcome: new/enlarging/enhancing MRI lesions.
  • Funding: MS Society of Great Britain and Northern Ireland; Bayer-Schering; others.

Limitations

  • Choice of main outcome measure.
  • Fairly short treatment duration.
  • Unclear generalizability to progressive MS.