A Phase 2b, Multi-center, Randomized, Double-blind, Placebo controlled Study of IMVT-1402 Treatment in Adult Participants with Chronic Inflammatory Demyelinating Polyneuropathy (CIDP)

The primary objective of this study is to evaluate the efficacy of IMVT-1402 compared to placebo in preventing relapse in adult participants with chronic inflammatory demyelinating polyneuropathy (CIDP), as assessed by the aINCAT score. This objective addresses the critical clinical need to prevent disease relapse in CIDP patients, which is associated with progressive functional deterioration and reduced quality of life.

The secondary objectives are:

• To evaluate the efficacy of IMVT-1402 compared to placebo as assessed by I-RODS (Inflammatory Rasch-built Overall Disability Scale).

• To evaluate the efficacy of IMVT-1402 compared to placebo as assessed by mean grip strength.

• To evaluate the efficacy of IMVT-1402 compared to placebo as assessed by MRC-SS (Medical Research Council Sum Score).

• To evaluate the efficacy of IMVT-1402 compared to placebo as assessed by aINCAT score.

The clinical trial enrolled a total of **92 participants** diagnosed with **Chronic Inflammatory Demyelinating Polyneuropathy (CIDP)**. The study population included both **male and female** subjects aged **18 years and older**, comprising adults and elderly individuals. Participants were required to meet clinical diagnostic criteria for typical CIDP or specific CIDP variants, including multifocal CIDP or motor CIDP, according to the 2021 European Academy of Neurology/Peripheral Nerve Society guideline. Electrodiagnostic test results supporting the diagnosis were mandatory for enrollment. A key characteristic of the trial population was that all participants were currently receiving chronic, stable doses of systemic **corticosteroids** administered as daily, every other day oral, or pulse regimens, or **immunoglobulin therapy** (intravenous or subcutaneous) with or without low-dose oral corticosteroids, for at least three months prior to screening. The selection process focused on patients with established CIDP requiring ongoing immunomodulatory treatment. No vulnerable populations were included in this trial.

This is a Phase 2b, multi-center, randomized, double-blind, placebo-controlled clinical trial evaluating the efficacy and safety of **IMVT-1402** in adult participants with **Chronic Inflammatory Demyelinating Polyneuropathy** (CIDP). The investigational medicinal product IMVT-1402 is a solution for injection containing **imeroprubart**, a human IgG1 monoclonal antibody against FcRn receptor, administered via the **subcutaneous** route. The maximum daily dose is 600 mg, with a maximum total dose of 46,800 mg over a maximum treatment period of 76 weeks. The control group receives **placebo** identical to the investigational medicinal product but without active substance. The trial is designed to evaluate the efficacy of IMVT-1402 compared to placebo in preventing relapse as assessed by adjusted Inflammatory Neuropathy Cause and Treatment (aINCAT) score.

The primary objective of the trial is to evaluate the efficacy of IMVT-1402 compared to placebo in preventing relapse as assessed by **aINCAT score**. The primary endpoint is defined as the proportion of participants remaining relapse-free by Week 24. Secondary endpoints include change from baseline to Week 24 in Inflammatory Rasch-built Overall Disability Scale (**I-RODS**), change from baseline to Week 24 in mean grip strength in the dominant hand, change from baseline to Week 24 in Medical Research Council Sum Score (**MRC-SS**), and change from baseline to Week 24 in aINCAT score.

Eligible participants must be at least 18 years of age at the time of signing the informed consent form. Participants must have met clinical diagnostic criteria for typical CIDP or one of the following CIDP variants: **multifocal CIDP** or **motor CIDP** per the 2021 European Academy of Neurology/Peripheral Nerve Society (EAN/PNS) Guideline on Diagnosis and Treatment of CIDP. **Electrodiagnostic test** results must support the diagnosis of CIDP per the EAN/PNS guideline. Participants must be currently receiving chronic, stable doses of systemic **corticosteroids** (daily or every other day oral or pulse regimen), or **immunoglobulin therapy** (intravenous immunoglobulin or subcutaneous immunoglobulin) with or without low dose oral corticosteroids, for at least 3 months for the treatment of CIDP at the time of the screening visit.

The trial includes a screening visit for assessment of eligibility criteria, followed by randomization and treatment initiation. Participants undergo regular follow-up visits for efficacy and safety assessments throughout the treatment period. The study includes visits at Week 24 for evaluation of primary and secondary endpoints. An end-of-study visit is conducted to assess final outcomes and safety parameters. The estimated recruitment start date is October 9, 2025, and the estimated end date is May 31, 2030. Participant involvement duration depends on treatment response and adherence to protocol requirements. Early termination from the study may occur due to relapse, unacceptable adverse events, withdrawal of consent, protocol violations, or investigator decision based on safety concerns.

The experimental medication **IMVT-1402** contains the active substance **imeroprubart**, a human IgG1 monoclonal antibody against the FcRn receptor. The product is formulated as a **solution for injection** and is manufactured by Immunovant Sciences GmbH. The active substance is classified as a protein of other origin. IMVT-1402 is administered via the **subcutaneous route**. The maximum daily dose is **600 mg**, with a maximum total dose of **46800 mg** over a maximum treatment period of **76 weeks**. The investigational medicinal product is administered using a medical device specifically designed for subcutaneous injection. This formulation is not a paediatric formulation.

The **placebo** used in this study is identical to the investigational medicinal product in appearance and formulation but contains no active substance. The placebo serves as the comparator treatment in this **randomized, double-blind, placebo-controlled study**. The matching placebo ensures maintenance of blinding throughout the trial, allowing for appropriate comparison of efficacy and safety outcomes between treatment groups in adult participants with **chronic inflammatory demyelinating polyneuropathy**.

Efficacy will be assessed through the evaluation of relapse prevention in participants with chronic inflammatory demyelinating polyneuropathy. The primary endpoint is the proportion of participants remaining relapse-free by Week 24, as assessed by adjusted Inflammatory Neuropathy Cause and Treatment (aINCAT) score. Secondary endpoints include change from baseline to Week 24 in Inflammatory Rasch-built Overall Disability Scale (I-RODS), change from baseline to Week 24 in mean grip strength in the dominant hand, change from baseline to Week 24 in Medical Research Council Sum Score (MRC-SS), and change from baseline to Week 24 in aINCAT score. These efficacy parameters will be measured and analyzed at the specified timepoint of Week 24 to determine the treatment effect of IMVT-1402 compared to placebo.