A systematic search of PubMed and Clinicialtrials.gov was conducted using pre-specified keywords following the PRISMA guidelines. RCTs studying the Inflammatory Neuropathy Cause And Treatment (INCAT) disability score, Inflammatory Rasch-built Overall Disability Scale (I-RODS), Medical Research Council (MRC) Sum score, Grip strength scores and relapse rates as primary outcomes were selected.

Five RCTs filled the necessary criteria and were included in the systematic review [n=284, male= 178(62.7%)]. A 0.2g/kg weekly dosing showed higher relapse rates (33-50%), and mild to no significant improvement in the post-treatment INCAT, I-RODS, Grip strength, and MRC SUM scores. A 0.4g/kg weekly SCIG showed significant clinical improvement and lesser relapses in patients (10-19%). Monthly maintenance therapy with hyaluronidase facilitated SCIG 10% also reduced the relapse rates by 9.7% [95% CI 4.5%, 19.6%]. Adverse events included local skin reactions (22% to 38.7%), infections (10% to 24.4%), headaches (7% to 35%), fatigue (12% to 35%), gastrointestinal issues such as nausea and diarrhoea (12% to 19.4%), CIDP worsening (18%), and hypertension (6.4%).