Inclusion Criteria:

• The subject or subject’s legally authorized representative is willing and able to understand and fully comply with study procedures and requirements, in the opinion of the investigator.
• The subject or the subject’s legally authorized representative has provided informed consent (that is, in writing, documented via a signed and dated ICF) and any required privacy authorization before the initiation of any study procedures.
• The subject is at least 18 years of age, inclusive, at the time of signing the ICF.
• The subject has a body weight of ≤ 150 kg.
• The subject has a documented diagnosis of typical CIDP, as confirmed by a neurologist specializing/experienced in neuromuscular diseases and consistent with the European Academy of Neurology/Peripheral Nerve Society (EAN/PNS) 2021 criteria (Van den Bergh et al., 2021).
• The subject has responded to IgG treatment in the past (documented partial or complete resolution of neurological symptoms and deficits).
• The subject has had disease activation within 18 months before screening, as documented in medical records and in the opinion of the investigator, defined as one of the following:
  • Clinically meaningful deterioration of symptoms on interruption or dose reduction of IgG treatment.
  • Clinically meaningful deterioration of symptoms requiring IgG treatment dose increase with subsequent clinical improvement.
  • Clinically meaningful deterioration of symptoms at the end of IgG treatment dose interval with improvement after next dose administration.
• The subject is on a stable dose of IGIV treatment, defined as no change greater than 10% in frequency or dose of IGIV therapy within the 12 weeks before and throughout screening within the dose range of 0.4 to 2.4 g/kg every 2 to 6 weeks (inclusive).
• The subject has an INCAT score >2 at screening.
• If the subject engages in sexual relations that carry a risk of pregnancy, they agree to use a highly effective contraceptive method (as defined in Section 10.4.2) for the period from screening until 30 days after the last dose of IP. Note: If hormonal contraceptives are used, they must be stabilized for at least 30 days before the start of the screening period.
• If the subject is capable of producing viable ova or sperm, they agree to not donate ova or sperm throughout the study period and for 30 days after the last dose of IP (see Section 5.3.4).

Exclusion Criteria: 

• The subject has a documented diagnosis of a CIDP variant per EAN/PNS 2021 criteria (Van den Bergh et al., 2021).
• The subject has any neuropathy of other causes, including the following:
  • Hereditary demyelinating neuropathies, such as hereditary sensory and motor neuropathy, Charcot-Marie-Tooth disease, and hereditary sensory and autonomic neuropathies.
  • Neuropathies secondary to infections, disorders, or systemic diseases such as Borrelia burgdorferi infection (Lyme disease), diphtheria, systemic lupus erythematosus, POEMS (polyneuropathy, organomegaly, endocrinopathy, M-protein, and skin changes) syndrome, osteosclerotic myeloma, diabetic and nondiabetic lumbosacral radiculoplexus neuropathy, lymphoma, amyloidosis.
  • Multifocal motor neuropathy.
  • Drug-, biologic-, chemotherapy-, or toxin-induced peripheral neuropathy.
  • Diabetic peripheral neuropathy.
• The subject has any chronic or debilitating disease, or central nervous disorder that causes neurological symptoms or that may interfere with assessment of CIDP or outcome measures, including (but not limited to) multiple sclerosis, arthritis, stroke, and Parkinson’s disease.
• The subject is required to take or has taken immunomodulatory/immunosuppressive agents (except IGIV) that include, but are not limited to, complement inhibitors, rituximab, efgartigimod, and chemotherapeutic drugs, within 6 months of screening.
• The subject is required to take or has taken systemic corticosteroids defined as > 10 mg/day prednisone-equivalent for > 14 days, within 6 months of screening.

Note: Subjects required to take or who have taken a dose of ≤ 10 mg/day prednisone-equivalent are eligible if their regimen has been stable for at least 3 months before screening and is expected to remain stable throughout the study.

• The subject has undergone plasma exchange within 3 months of screening.
• The subject has a history of immunoglobulin M (IgM) paraproteinemia, including IgM monoclonal gammopathy with high titer of antibody to myelin-associated glycoprotein.
• The subject has immunoglobulin A (IgA) deficiency (IgA 100 mm Hg and/or systolic blood pressure > 160 mm Hg during the screening confirmed on 2 measures > 30 minutes apart).
• The subject has an acquired or Inherited Thrombophilic Disorder, such as Protein C Deficiency, Protein S Deficiency, Antithrombin Deficiency, or Primary Antiphospholipid Antibody Syndrome.
• The subject has experienced deep vein thrombosis or arterial thromboembolic events (eg, cerebrovascular accident, pulmonary embolism) within 12 months of screening.
• The subject has any medical condition, laboratory finding, or physical examination finding that precludes participation or with clinical evidence of any significant acute or chronic disease that, in the opinion of the investigator, may interfere with successful completion of the study or place the subject at undue medical risk.
• The subject has known or suspected intolerance or hypersensitivity to the IP, closely related compounds, or any of the stated ingredients.
• The subject has a history of hypersensitivity or allergies to human blood products such as human IgG, albumin, or other blood components.
• The subject has known history of positive result for or is positive at screening for one or more of the following:
  • Hepatitis B surface antigen (HBsAg).
  • Polymerase chain reaction (PCR) for hepatitis C virus (HCV).
  • PCR for HIV Type 1 and Type 2.

Note: Cured subjects with a history of HCV infection who have a negative PCR test at screening are eligible.

• The subject has any of the following laboratory values at screening:
  • Hemoglobin (Hgb) level of < 10.0 g/dL.
  • Hemoglobin (Hgb) level of 7.0%.
  • Platelet count < 100,000 cells/µL
  • Absolute neutrophil count < 1000 cells/µL.
  • Serum aspartate aminotransferase (AST) > 2.5× the upper limit of normal (ULN).
  • Serum alanine aminotransferase (ALT) > 2.5× ULN.
  • Positive pregnancy test.
• The subject has participated in another clinical study involving an IP or investigational device within 30 days before screening or is scheduled to participate in another clinical study involving an IP or investigational device during the course of this study.
• The subject is a study site employee, an immediate family member (eg, spouse, parent, child, sibling), or is in a dependent relationship with a study site employee who is involved in conduct of this study, or may consent under duress.

Note: Other protocol defined Inclusion/Exclusion Criteria may apply.

Eligibility last updated 10/29/2024. Questions regarding updates should be directed to the study team contact.