To evaluate the safety and efficacy of subcutaneous immunoglobulin (SCIg) as a maintenance therapy for patients with chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) by analyzing data from randomized controlled trials (RCTs).

CIDP is a peripheral nerve disorder characterized by progressive weakness and sensory loss. SCIg has emerged as a maintenance therapy for CIDP patients responsive to intravenous immunoglobulin (IVIG). However, there is limited data on the long-term efficacy and safety of SCIg in larger trials.

A systematic search of major databases was conducted. The included studies were analyzed on Revman 5.3 using the random effects meta-analysis model. Mean differences (MD) were calculated for continuous outcomes (efficacy), while odds ratios (ORs) were determined for dichotomous outcomes (relapse rates and safety).

Four RCTs with 559 subjects were included in this meta-analysis. SCIg significantly reduced the odds of relapse compared to placebo (OR = 0.26, 95% CI: 0.14–0.48, p < 0.0001). SCIg also decreased the Inflammatory Neuropathy Cause and Symptom (INCAT) score (MD = -0.8, 95% CI: -1.22 to -0.38, p = 0.0002), increased the Medical Research Council Muscle (MRC) sum score (MD = 2.22, 95% CI: 1.16 to 3.28, p < 0.0001), and improved the Inflammatory Rasch-Built Overall Disability Scale (iRODS) score (MD = 4.06, 95% CI: 0.03 to 8.09, p = 0.05). SCIg was associated with higher odds of infusion site reactions (OR = 11.24, 95% CI: 2.99–42.28, p = 0.0003), but other safety parameters were not significant.

SCIg demonstrates efficacy in reducing relapse rates and improving clinical scores such as INCAT and iRODS, while also being well tolerated by most patients. These findings support the potential of SCIg as a viable long-term maintenance therapy for CIDP, with its favorable safety profile and ease of administration. Larger trials are warranted to confirm these results and better understand its role in CIDP management.