Intravenous Immunoglobulin in Idiopathic Inflammatory Myopathies: a Practical Guide for Clinical Use

Area of Science:

• Rheumatology
• Immunology
• Neurology

Background:

• Idiopathic inflammatory myopathies (IIM) are autoimmune disorders impacting muscles and skin, leading to significant morbidity.
• Optimal treatment strategies for IIM remain uncertain, necessitating exploration of effective therapeutic options.

Purpose of the Study:

• To provide a practical guide for using intravenous immunoglobulin (IVIG) and subcutaneous immunoglobulin (SCIG) in managing IIM.
• To summarize considerations for IVIG use in special circumstances like dysphagia, ILD, calcinosis cutis, and pregnancy.
• To discuss IVIG safety, formulations, and associated costs in IIM management.

Main Methods:

• Review of recent literature and clinical experience.
• Focus on practical application of IVIG/SCIG in various IIM subtypes (DM, PM, IMNM, IBM).
• Inclusion of special circumstances and safety/cost considerations.

Main Results:

• IVIG has demonstrated safety and efficacy in IIM, supported by recent high-impact studies, including a Phase III trial in DM.
• IVIG is effective for both muscular and extra-muscular manifestations across various IIM types.
• IVIG can be used as a first-line, steroid-sparing agent or as an adjunct therapy, tailored to clinical scenarios.

Conclusions:

• IVIG is a well-tolerated treatment with a good safety profile for IIM.
• Accessibility and cost remain barriers to widespread IVIG use.
• Recent evidence supports IVIG as a valuable therapeutic option in the management of IIM.