IVIG in the Treatment of Autoimmune Small Fiber Neuropathy With TS-HDS, FGFR-3, or Plexin D1 Antibodies

Official title

Intravenous Immunoglobulin (IVIG) in the Treatment of Small Fiber Neuropathy Due to TS-HDS, FGFR-3, or Plexin D1 Antibodies: a Double Blinded Placebo-controlled Phase II Trial

Overview

This study will enroll patients with small fiber neuropathy (SFN). The study will look at an intravenous immunoglobulin (IVIG) called Panzyga. Panzyga is approved by the FDA as a therapy for Primary humoral immunodeficiency (PI) in patients 2 years of age and older; Chronic immune thrombocytopenia (ITP) in adults and Chronic inflammatory demyelinating polyneuropathy (CIDP) in adults. It has not been approved by the FDA for use in SFN. There is mounting evidence that Intravenous Immunoglobulin (IVIG) can cause pain reduction and improve objective nerve fiber densities on skin biopsies in great numbers in SFN patients. The primary outcome is quantified improvement in intraepidermal nerve fiber density (IENFD) on repeat skin punch biopsy after 6 months of IVIG treatment.

Detailed description

Small fiber neuropathy (SFN) is an increasingly prevalent diagnosis in neurology and neuromuscular centers. Modern diagnostic techniques, including skin biopsies and autonomic nervous testing are helping to find SFN in many patients with undiagnosed pain syndromes including fibromyalgia. The prevalence is rising for SFN, and an immune etiology may underlie 19%-34% of cases. While there is no standard of care treatment, current treatment strategies for SFN include long-term steroid therapy which come with a host of side effects. There is mounting evidence that Intravenous Immunoglobulin (IVIG) can cause pain reduction and improve objective nerve fiber densities on skin biopsies in great numbers in SFN patients, as well as improving validated questionnaire scores monitoring symptom burden and disability. However, neither IVIG nor any other immunosuppressant has been studied in a sufficiently powered and adequately dosed controlled, randomized clinical trial to demonstrate efficacy.

Interventions

• Drug Panzyga IVIG
  Immune Globulin Infusion 10% (Human)
• Drug Placebo
  0.9% NaCl prepared as the calculated dose equivalent volume to IVIG.

Primary outcome measures

• quantified change in intraepidermal nerve fiber density (IENFD) [Time frame: Week 24]

Secondary outcome measures (4)

• Change in visual analogue pain scale responses [Time frame: baseline and Week 28]
• Change in Small Fiber Neuropathy-Rasch Overall Disability Scale (SFN-RODS) score [Time frame: baseline and Week 28]
• Change in Small Fiber Neuropathy-Symptom Inventory Questionnaire (SFN-SIQ) score [Time frame: baseline and Week 28]
• Change in Utah Early Neuropathy Scale (UENS) examination scores [Time frame: baseline and Week 28]

Eligibility criteria

Inclusion criteria

• Patients ≥ age 18
• Patient with clinical and biopsy evidence of pure small fiber neuropathy (with or without dysautonomia) as evidenced by reduced IENFD on skin biopsy using PGP 9.5 as the immunostain. Biopsy must have been performed within 12 months of study enrollment. If biopsies were not done at CRL, they will be repeated and done at 3 sites (upper and lower thigh, lower calf), to have consistent and equivalent biopsy data with the follow up biopsy done after 6 mos of treatment
• Patients must have elevated and/or abnormal titers of autoantibodies to TS-HDS-IgM, FGFR3-IgG, or Plexin-D1 measured by the Washington University Neuromuscular Laboratory (St Louis) within 12 mos of enrollment
• Patients must have a baseline pain score on a visual analogue scale (VAS) of Greater or equal to 4/10
• Patients must have a baseline Utah Early Neuropathy Scale (UENS) score of Greater or equal to 4/10
• Small Fiber Neuropathy Screening List (SFNSL) score of 11/84 or greater
• Non-pregnant, non-lactating female. Females of reproductive potential must use 2 forms of contraception or continuously abstain from heterosexual sex during treatment

Exclusion criteria

• Any other known cause for small fiber neuropathy other than the presence of the elevated titers of TS-HDS-IgM, FGFR3-IgG, or Plexin-D1 autoantibodies
• Patients with generalized, severe musculoskeletal conditions other than SFN that prevent a sufficient assessment of the patient by the physician
• Electromyography/nerve conduction study (EMG/NCS) evidence of large fiber polyneuropathy, to be confirmed by study PI
• Underlying severe heart, kidney, liver disease, or HIV infection, (Note: If there is no previous HIV test result documented within the last 5 years, a test may be performed in order to confirm eligibility)
• Patients with a history of deep vein thrombosis within the last year prior to baseline visit or pulmonary embolism ever; patients with susceptibility to embolism or deep vein thrombosis
• Known significant IgA deficiency with antibodies to IgA
• History of hypersensitivity, anaphylaxis or severe systemic response to immuno-globulin, blood or plasma derived products, or any component of IVIG 10%
• Known blood hyperviscosity, or other hypercoagulable states
• Use of IgG products within six months prior to enrollment
• Patients with a history of drug or alcohol abuse within the past five years prior to enrollment
• Patients unable to understand or unwilling or unable to comply with the study protocol

Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.

Healthy volunteers: No

Study design

Allocation

Randomized

Model

Parallel assignment

Masking

Double blind

Primary purpose

Treatment

Study locations

United States · 1 center

• Endeavor Health — Glenview

Publications

• Peters MJ, Bakkers M, Merkies IS, Hoeijmakers JG, van Raak EP, Faber CG. Incidence and prevalence of small-fiber neuropathy: a survey in the Netherlands. Neurology. 2013 Oct 8;81(15):1356-60. doi: 10.1212/WNL.0b013e3182a8236e. Epub 2013 Aug 30. PMID 23997150
• Antoine JC, Boutahar N, Lassabliere F, Reynaud E, Ferraud K, Rogemond V, Paul S, Honnorat J, Camdessanche JP. Antifibroblast growth factor receptor 3 antibodies identify a subgroup of patients with sensory neuropathy. J Neurol Neurosurg Psychiatry. 2015 Dec;86(12):1347-55. doi: 10.1136/jnnp-2014-309730. Epub 2015 Jan 27. PMID 25628376
• Darabi K, Abdel-Wahab O, Dzik WH. Current usage of intravenous immune globulin and the rationale behind it: the Massachusetts General Hospital data and a review of the literature. Transfusion. 2006 May;46(5):741-53. doi: 10.1111/j.1537-2995.2006.00792.x. PMID 16686841
• Singleton JR, Bixby B, Russell JW, Feldman EL, Peltier A, Goldstein J, Howard J, Smith AG. The Utah Early Neuropathy Scale: a sensitive clinical scale for early sensory predominant neuropathy. J Peripher Nerv Syst. 2008 Sep;13(3):218-27. doi: 10.1111/j.1529-8027.2008.00180.x. PMID 18844788
• Souayah N, Chin RL, Brannagan TH, Latov N, Green PH, Kokoszka A, Sander HW. Effect of intravenous immunoglobulin on cerebellar ataxia and neuropathic pain associated with celiac disease. Eur J Neurol. 2008 Dec;15(12):1300-3. doi: 10.1111/j.1468-1331.2008.02305.x. PMID 19049545
• Levine TD, Kafaie J, Zeidman LA, Saperstein DS, Massaquoi R, Bland RJ, Pestronk A. Cryptogenic small-fiber neuropathies: Serum autoantibody binding to trisulfated heparan disaccharide and fibroblast growth factor receptor-3. Muscle Nerve. 2020 Apr;61(4):512-515. doi: 10.1002/mus.26748. Epub 2019 Nov 6. PMID 31650561
• Bitzi LM, Lehnick D, Wilder-Smith EP. Small fiber neuropathy: Swiss cohort characterization. Muscle Nerve. 2021 Sep;64(3):293-300. doi: 10.1002/mus.27340. Epub 2021 Jun 16. PMID 34075618
• de Greef BTA, Hoeijmakers JGJ, Gorissen-Brouwers CML, Geerts M, Faber CG, Merkies ISJ. Associated conditions in small fiber neuropathy - a large cohort study and review of the literature. Eur J Neurol. 2018 Feb;25(2):348-355. doi: 10.1111/ene.13508. Epub 2017 Dec 18. PMID 29112785

Identifiers

NCT: NCT04153422 · 2025-0046

Primary sources (government registries)

• ClinicalTrials.gov (US NIH)

View this study on ClinicalTrials.gov ↗