Chronic Inflammatory Demyelinating Polyneuropathy (CIDP) is a rare, long-lasting autoimmune disease that can worsen over time. CIDP occurs when the immune system mistakenly attacks the covering of some nerve cells in the arms and legs. CIDP can lead to difficulty walking or performing typical daily tasks without help.

The Emvigorate study is designed to evaluate how the investigational study drug* may work (also known as efficacy) and how safe it is for the use in adults living with CIDP. This study will evaluate the investigational study drug compared to the current standard-of-care intravenous immunoglobulin (IVIg).

*The investigational study drug, empasiprubart, is not approved by any regulatory agency for the use in CIDP as efficacy and safety have not been established.

You may be eligible to participate if you are:

• At least 18 years old
• Not pregnant or actively trying to get pregnant
• Diagnosed with CIDP

Additional criteria to participate apply which the study doctor will discuss with you.

The study will be conducted in two parts, Part A and Part B.

Part A: 6 months. In part A, enrolled participants will be randomly assigned to two separate treatment groups to receive either:

• Empasiprubart plus placebo IVIg, or
• IVIg plus placebo.

You will never receive placebo-only treatments. The placebo will always be combined with either investigational study drug or IVIg.

The investigational study drug (or its placebo) will be administered monthly, the IVIg (or its placebo) treatment schedule will remain the same as the standard treatment routine you were on prior to starting the study. Both are given through an infusion into a vein in your arm (intravenously).

You will be randomly assigned to one of the groups, and neither you nor your study doctor will know which group you are in. You have a 50% chance to receive the investigational study drug. In case of an emergency, you will receive medical care, and if needed, the study doctor can quickly find out which treatment group you were in to ensure your safety.

Part B: All participants will receive the investigational study drug for up to 24 months to evaluate safety and efficacy. You will not receive IVIg during part B.

For up to 15 months after you complete Part B, the study team will continue to monitor you for safety. This will include physical check-ups, blood work and urine tests, and answering health-related questions.