Placebo effect in chronic inflammatory demyelinating polyneuropathy: The PATH study and a systematic review.

Journal Article (Journal Article;Systematic Review)

The Polyneuropathy And Treatment with Hizentra (PATH) study required subjects with chronic inflammatory demyelinating polyneuropathy (CIDP) to show dependency on immunoglobulin G (IgG) and then be restabilized on IgG before being randomized to placebo or one of two doses of subcutaneous immunoglobulin (SCIG). Nineteen of the 51 subjects (37%) randomized to placebo did not relapse over the next 24 weeks. This article explores the reasons for this effect. A post-hoc analysis of the PATH placebo group was undertaken. A literature search identified other placebo-controlled CIDP trials for review and comparison. In PATH, subjects randomized to placebo who did not relapse were significantly older, had more severe disease, and took longer to deteriorate in the IgG dependency period compared with those who relapsed. Published trials in CIDP, whose primary endpoint was stability or deterioration, had a mean non-deterioration (placebo effect) of 43%, while trials with a primary endpoint of improvement had a placebo response of only 11%. Placebo is an important variable in the design of CIDP trials. Trials designed to show clinical improvement will have a significantly lower effect of this phenomenon than those designed to show stability or deterioration.

Full Text

Duke Authors

Cited Authors

  • Lewis, RA; Cornblath, DR; Hartung, H-P; Sobue, G; Lawo, J-P; Mielke, O; Durn, BL; Bril, V; Merkies, ISJ; Bassett, P; Cleasby, A; van Schaik, IN; PATH study group,

Published Date

  • September 2020

Published In

Volume / Issue

  • 25 / 3

Start / End Page

  • 230 - 237

PubMed ID

  • 32627277

Pubmed Central ID

  • PMC7497019

Electronic International Standard Serial Number (EISSN)

  • 1529-8027

Digital Object Identifier (DOI)

  • 10.1111/jns.12402


  • eng

Conference Location

  • United States