Treatment Impact of Efgartigimod PH20 SC on Grip Strength Assessment in Patients with Chronic Inflammatory Demyelinating Polyradiculoneuropathy (CIDP): Post Hoc Analysis of the ADHERE/ADHERE+ Study
Richard Lewis1, Christian Eggers2, Rachel Daut3, Frank Leypoldt4, Giuseppe Lauria Pinter5, Luis Querol6, Mark Stettner7, Pieter A. van Doorn8, Simon Rinaldi9, Thomas Skripuletz10, Arie Gafson3, Geoffrey Istas3, Arne De Roeck3, Katerina Anokhina3, Jeffrey A. Allen11
1Cedars-Sinai Medical Center, 2Kepler University Hospital, 3argenx, 4Institute of Clinical Chemistry, Christian-Albrecht University of Kiel; University Medical Center Schleswig-Holstein, 5IRCCS Istituto Neurologico Carlo Besta; University of Milan, 6Hospital de la Santa Creu I Sant Pau, Universitat Autònoma de Barcelona, 7University Medicine Essen, 8Erasmus University Medical Center, 9University of Oxford, 10Hannover Medical School, 11University of Minnesota
Objective:
Assess the effect of subcutaneous (SC) efgartigimod PH20 on grip strength in CIDP.
Background:
CIDP is an immune-mediated polyradiculoneuropathy characterized by proximal and distal weakness and sensory disturbance that can lead to irreversible disability.
Design/Methods:
In ADHERE (NCT04281472), participants receiving CIDP treatment entered a ≤12-week run-in during which CIDP-treatments were withdrawn to identify participants with active disease. Participants received open-label weekly efgartigimod PH20 SC 1000 mg (stage-A). Responders were randomized (1:1) to efgartigimod or placebo for ≤48 weeks (stage-B). Participants with clinical deterioration or who completed stage-B without clinical deterioration entered ADHERE+ (NCT04280718). We report a post hoc analysis of grip strength in stage-A responders from run-in baseline through ADHERE+ Week 36 (minimal clinically important difference [MCID]: ≥8 kPa).
Results:
322 participants entered stage-A; 221 were randomized and treated in stage-B. Among participants receiving efgartigimod during stage-B (n=97), mean (SE) and median dominant hand grip strength scores at run-in baseline were 44.4 kPa (2.39) and 47.0 kPa. Mean (SE) and median changes from run-in baseline to stage-A last assessment (n=97), stage-B last assessment (n=97), and ADHERE+ Week 36 (n=76) were 9.1 kPa (1.70) and 6.0 kPa; 12.0 kPa (2.34) and 7.0 kPa; and 18.2 kPa (2.57) and 12.5 kPa, respectively. A similar trend was noted for non-dominant grip strength scores. In participants who responded to efgartigimod treatment in stage-A, mean (SE) and median changes from run-in baseline to ADHERE+ Week 36 (n=149) in dominant hand grip strength scores were 17.5 kPa (2.02) and 10.0 kPa; non-dominant hand: 17.8 kPa (2.00) and 13.0 kPa. During ADHERE+ Week 36, 50.3% (75/149) and 38.9% (58/149) of participants achieved ≥16 or ≥24 kPa improvement, respectively, in grip strength in any hand.
Conclusions:
Long-term efgartigimod PH20 SC treatment improved grip strength in participants with CIDP; a 2–3 fold improvement in MCID was reported in ~40–50% of participants.
Generative AI Usage
No, did not use generative AI in the drafting or editing in this abstract.
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