Neurology · Clinical trials
Chronic Inflammatory Demyelinating Polyneuropathy (CIDP) Clinical Trials
Approved therapies, the pivotal-trial endpoints they were judged on, the magnitude of benefit — and the drugs that failed their endpoints, and why.
Indication overview
About chronic inflammatory demyelinating polyneuropathy (cidp) — and why its trials are hard
Chronic inflammatory demyelinating polyneuropathy (CIDP) is an acquired immune-mediated neuropathy characterized by progressive or relapsing, symmetric proximal and distal weakness with sensory loss evolving over at least eight weeks, distinguishing it from Guillain-Barré syndrome. Pathophysiology involves both cellular and humoral attack on peripheral myelin; nerve conduction studies show demyelination and CSF often shows albuminocytologic dissociation. A nodal/paranodal antibody subset (e.g., anti-neurofascin-155, anti-contactin-1) responds poorly to standard therapy. First-line disease-modifying options are well established: intravenous immunoglobulin (ICE trial), corticosteroids, and plasma exchange, with subcutaneous immunoglobulin (Hizentra, PATH trial) approved for maintenance to reduce relapse. In 2024 the FcRn antagonist efgartigimod alfa/hyaluronidase (Vyvgart Hytrulo) was approved based on the ADHERE trial, providing a targeted IgG-lowering maintenance option that significantly reduced relapse risk. Treatment aims to induce and maintain improvement while minimizing long-term corticosteroid exposure. Some patients become treatment-dependent, and accurate diagnosis is essential given frequent misdiagnosis.
Approved therapies & pivotal evidence
What's been approved — and by how much it moved the endpoint
| Drug (brand) | Approved | Setting | Pivotal trial | Primary endpoint | Magnitude of benefit |
|---|---|---|---|---|---|
| Intravenous immunoglobulin (IVIG) (Gamunex-C) | 2008 (CIDP indication) | First-line induction and maintenance | ICE (Phase 3) | Proportion improved/maintained on adjusted INCAT disability score | ~54% improved on IVIG vs ~21% placebo; established durable maintenance benefit |
| Corticosteroids (e.g., prednisone) ((generic)) | long-established | First-line induction immunotherapy | Historical RCTs; pulsed dexamethasone/methylprednisolone studies | Disability and impairment improvement | Effective first-line; limited by long-term steroid toxicity |
| Subcutaneous immunoglobulin (SCIg) (Hizentra) | 2018 | Maintenance therapy to prevent relapse | PATH (Phase 3) | CIDP relapse or withdrawal | Relapse ~33% (0.4 g/kg) and ~39% (0.2 g/kg) vs 63% placebo; enabled home-based maintenance |
| Efgartigimod alfa/hyaluronidase (Vyvgart Hytrulo) | 2024 | Maintenance therapy in adults with CIDP | ADHERE (Phase 2/3) | Time to first clinical deterioration (relapse) in randomized withdrawal | ~61% reduction in relapse risk vs placebo (hazard ratio ~0.39); FcRn antagonist lowering pathogenic IgG |
Where trials have failed
Drugs that missed their endpoint — and what contributed
The most instructive lessons in chronic inflammatory demyelinating polyneuropathy (cidp) development come from programmes that failed the endpoint that mattered.
| Drug / trial | Endpoint outcome | What contributed |
|---|---|---|
| Fingolimod — FORCIDP (Phase 3) | Terminated for futility | The S1P-receptor modulator did not reduce CIDP relapse/worsening versus placebo, and the trial was stopped early. |
| Methotrexate — RMC trial (Phase 2/3) | No significant steroid/IVIG-sparing benefit | Failed to demonstrate meaningful reduction in IVIG or corticosteroid requirement compared with placebo. |
Choosing the right endpoint
Primary endpoints that matter in chronic inflammatory demyelinating polyneuropathy (cidp) trials
- INCAT disability score (adjusted) — Ordinal arm/leg disability scale; the classic CIDP trial primary endpoint (used in ICE).
- Time to relapse / clinical deterioration — Primary endpoint in randomized-withdrawal maintenance designs such as ADHERE and PATH.
- I-RODS (Inflammatory Rasch-built Overall Disability Scale) — Patient-reported activity/participation measure increasingly used as a sensitive functional endpoint.
- Grip strength — Objective, responsive measure of neuromuscular function used as a secondary endpoint.
- MRC sum score — Composite muscle strength assessment tracking impairment change.
How iNGENū runs chronic inflammatory demyelinating polyneuropathy (cidp) trials
Physician-led design, built for FDA submission
Endpoint & biomarker strategy
Board-certified specialists design endpoints and patient selection aligned to current FDA guidance for this indication.
FDA-ready data
Built to ICH-GCP and 21 CFR 312.120, with direct FDA submission — data accepted by the FDA, EMA and MHRA.
Faster, lower-cost delivery
~4-week ethics via the TGA CTN scheme, up to 43.5% R&D rebate, and 80–90% below US CRO cost.
Request a fixed-milestone proposal and a tailored endpoint & feasibility summary for this indication.
Frequently asked questions
Chronic Inflammatory Demyelinating Polyneuropathy (CIDP) clinical trials — FAQs
How is CIDP distinguished from Guillain-Barré syndrome?
What are the standard first-line treatments?
How does efgartigimod work in CIDP?
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