Abstract
Patients with chronic inflammatory demyelinating polyneuropathy (CIDP) received immune globulin intravenous, 10% caprylate/chromatography purified (IGIV‐C, Gamunex; n = 59) or placebo (n = 58) every 3 weeks for up to 24 weeks (first period) in a randomized, double‐blind, parallel‐group, response‐conditional, crossover study. Motor and sensory nerves were assessed at baseline and endpoint/week 24. A nonsignificant trend toward improvement in the proximal amplitude of the most severely affected motor nerve was observed with IGIV‐C (0.69 ± 1.86 mV) versus placebo (0.47 ± 2.29 mV), and a greater improvement of 1.08 ± 2.15 mV with IGIV‐C versus 0.46 ± 2.03 mV with placebo (P = 0.089) was observed with exclusion of data from Erb's point stimulation. Greater improvements from baseline favoring IGIV‐C were observed for 127/142 electrophysiologic parameters. The averaged motor amplitudes from all motor nerves significantly improved with IGIV‐C versus placebo [treatment difference, 0.62 mV; 95% confidence interval (CI), 0.05, 1.20; P = 0.035], and conduction block decreased significantly (treatment difference, −5.54%; 95% CI, −10.43, −0.64; P = 0.027), particularly in the lower limbs. Overall, the data suggest that IGIV‐C improves electrophysiologic parameters in CIDP. Muscle Nerve, 2009