Analysis of Relapse by Inflammatory Rasch-built Overall Disability Scale Status in the PATH Study of Subcutaneous Immunoglobulin in Chronic Inflammatory Demyelinating Polyneuropathy

Department of Neurology, Maastricht University Medical Center, Maastricht, Netherlands. Department of Neurology, Curaçao Medical Center, Willemstad, Curaçao. Department of Neurology, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, Netherlands. Spaarne Gasthuis, Haarlem, Netherlands. Department of Medicine (Neurology), University Health Network, University of Toronto, Toronto, Canada. Institute for Research and Medical Consultations, Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia. Department of Neurology, UKD and Center for Neurology and Neuropsychiatry, LVR Klinikum, Medical Faculty, Heinrich Heine University, Düsseldorf, Germany. Brain and Mind Centre, University of Sydney, Sydney, Australia. Medical University of Vienna, Vienna, Austria. Department of Neurology, Cedars-Sinai Medical Center, Los Angeles, CA, USA. Department of Neurology, Nagoya University Graduate School of Medicine, Nagoya, Japan. CSL Behring, Marburg, Germany. Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, USA.

Journal of the peripheral nervous system : JPNS. 2022
Abstract
BACKGROUND AND AIMS Clinical trials in chronic inflammatory demyelinating polyneuropathy (CIDP) often assess efficacy using the ordinal Inflammatory Neuropathy Cause and Treatment (INCAT) disability score. Here, data from the PATH study was reanalyzed using change in Inflammatory Rasch-built Overall Disability Scale (I-RODS) to define CIDP relapse instead of INCAT. METHODS The PATH study comprised an intravenous immunoglobulin (IVIG) dependency period and an IVIG (IgPro10 [Privigen®]) restabilization period; subjects were then randomized to weekly maintenance subcutaneous immunoglobulin (SCIG; IgPro20 [Hizentra®]) 0.2 g/kg or 0.4 g/kg or placebo for 24 weeks. CIDP relapse was defined as ≥1-point deterioration in adjusted INCAT, with a primary endpoint of relapse or withdrawal rates. This retrospective exploratory analysis redefined relapse using I-RODS via three different cut-off methods: an individual variability method, fixed cut-off of ≥8-point deterioration on I-RODS centile score or ≥4-point deterioration on I-RODS raw score. RESULTS Relapse or withdrawal rates were 47% for placebo, 34% for 0.2 g/kg IgPro20 and 19% for 0.4 g/kg IgPro20 using the raw score; 40%, 28% and 15%, respectively using the centile score, and 49%, 40% and 27%, respectively using the individual variability method. INTERPRETATION IgPro20 was shown to be efficacious as a maintenance therapy for CIDP when relapse was defined using I-RODS. A stable response pattern was shown for I-RODS across various applied cut-offs, indicating that any could be used in future clinical trials.
Study details
Language : eng
Credits : Bibliographic data from MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine