Intravenous immunoglobulin for chronic residual peripheral neuropathy in microscopic polyangiitis: A multicentre...

Area of Science:

• Rheumatology
• Neurology
• Immunology

Background:

• Microscopic polyangiitis (MPA) is a systemic vasculitis that can cause neuropathy.
• Glucocorticoid-refractory neuropathy presents a treatment challenge in MPA patients.
• Intravenous immunoglobulin (IVIg) is a potential therapeutic option for autoimmune neuropathies.

Purpose of the Study:

• To evaluate the efficacy and safety of IVIg in patients with glucocorticoid-refractory neuropathy associated with MPA.
• To compare the change in manual muscle test (MMT) sum scores between IVIg and placebo groups.

Main Methods:

• Phase 3, multicentre, randomised, double-blind, placebo-controlled, parallel-group trial.
• 37 patients with MPA-associated neuropathy received IVIg or placebo intravenously for 5 days at baseline and at 4 and 8 weeks.
• Primary endpoint: change in MMT sum score at 8 weeks; secondary endpoint: change at 4 weeks.

Main Results:

• The least squares mean change in MMT sum score at 8 weeks was 9.02 for IVIg and 6.71 for placebo (p=0.345).
• At 4 weeks, the MMT sum score change was 6.81 for IVIg and 2.83 for placebo (p=0.129).
• No new safety concerns were identified with IVIg treatment.

Conclusions:

• While MMT scores improved in both groups, IVIg did not demonstrate statistically significant superiority over placebo.
• The study suggests no clear efficacy of IVIg for glucocorticoid-refractory neuropathy in MPA patients.
• IVIg was found to be safe in this patient population.