Kuwabara S, et al. – An analysis was performed to examine the efficacy and safety of longer–term intravenous immunoglobulin (Ig) therapy in patients with chronic inflammatory demyelinating polyneuropathy (CIDP) for 52 weeks. For patients with CIDP, maintenance treatment with 1.0 g/kg intravenous Ig every 3 weeks was an efficacious therapy, and almost 70% of them had a sustained remission for 52 weeks. Thrombotic complications had to be carefully monitored, especially in elderly patients with vascular risk factors.

• The authors conducted an open-label phase 3 clinical trial conducted in 49 Japanese tertiary centres.
• They included 49 patients with CIDP who fulfilled diagnostic criteria.
• Intravenous Ig therapy (0.4 g/kg/day for five consecutive days), maintenance dose intravenous Ig (1.0 g/kg) was given every 3 weeks for up to 52 weeks after an induction.
• The responder rate at week 28 and relapse rate at week 52 were the primary outcome measures.
• They defined the response and relapse with the adjusted Inflammatory Neuropathy Cause and Treatment scale.

• The responder rate was 77.6% (38/49 patients at week 28; 95% CI 63% to 88%), and the 38 responders continued the maintenance therapy.
• 4 of the 38 (10.5%) had a relapse (95% CI 3% to 25%) at week 52.
• 34 (69.4%) of the 49 enrolled patients had a maintained improvement during 52 weeks.
• The authors observed adverse events in 94% of the patients; 2 patients (66-year-old and 76-year-old men with hypertension or diabetes) developed cerebral infarction (lacunar infarct with good recovery), and the other adverse effects were mild and resolved by the end of the study period.