INTRODUCTION: We evaluated the safety of GAMMAGARD LIQUID (GGL), an IVIG 10% therapy, versus comparator IVIGs with US approval to treat chronic inflammatory demyelinating polyradiculoneuropathy (CIDP).
OBJECTIVE: Determine rates of adverse events of special interest (AESIs) in patients with CIDP initiating GGL versus comparator IVIGs by prior treatment status (immunoglobulin-naive and immunoglobulin-experienced) using real-world healthcare insurance databases.
METHODS: This nonrandomized active-comparator new-user cohort study of adults with CIDP used the Optum Clinformatics® and MarketScan® databases (Jan-1-2008–Dec-31-2019; protocol registered a priori [NCT05363358]). Treatment groups comprised GGL and US-approved comparator IVIGs for CIDP: Gammaked, Gamunex-C and Privigen (all human IVIG 10%). AESI rates (thrombotic/hemolytic events, acute kidney injury) were compared between groups within propensity score-weighted samples using hazard ratios (HR), time-specific risk ratios (RR) and risk differences (RD). Database-specific estimates were pooled with meta-analysis.
RESULTS: Data from eligible patients in Optum (GGL, n=644; comparators, n=1293) and MarketScan (GGL, n=1441; comparators, n=2708) were analyzed, with good between-group comparability after propensity score weighting. AESIs were rare across cohorts, and database-pooled estimates were consistent, with no overall differences (e.g., for patients initiating GGL versus comparator IVIGs, pooled thrombosis HR=1.35 [95% confidence interval 0.84, 2.15]; 1-year specific RR=0.86 [0.47, 1.57]; RD=−0.0008 [−0.0138, 0.0122]). Time-specific thrombosis rate estimates showed some differences; overall 1-year risk was lower for GGL versus comparators in Optum and similar in MarketScan.
SUMMARY/CONCLUSION: This large real-world study evaluated risks of rare IVIG-associated AESIs using methods to control for confounding. There were similar AESI risks for different IVIGs.
