Converting Between Glycine-Stabilized Intravenous Immune Globulin Products: Incidence of Adverse Events

Purpose: The literature describing the incidence of ADEs when converting patients between Intravenous Immune Globulin (IVIg) products is limited. The purpose of this study is to evaluate the incidence of ADE when converting between two glycine- stabilized products, Gamunex-C and Gammagard Liquid.

Methods: This prospective study included all inpatient and outpatient adult patients at our center who received Gamunex-C or Gammagard Liquid IVIg from November 2011- April 2012. The objective was to compare the incidence and significance of ADEs in adult patients converted from Gamunex to Gammagard Liquid. Patients included received at least two pre-conversion doses of Gamunex (control) and two post-conversion doses of Gammagard (intervention). Patients served as their own control, therefore, baseline demographics were identical. ADE were considered significant if patients experienced rigors, decreased oxygen (O2) saturation >5% from baseline, or become hypotensive, defined as systolic blood pressure less than 90. Patients were excluded if they received IVIG by subcutaneous route.

Results: A total of 86 patients were converted from Gamunex-C to Gammagard Liquid. The total number of infusions in each arm were 172 and 171, respectively. No Gamunex patients experienced ADEs. A total of seven patients in the Gammagard group experienced ADEs for a total of 16 ADEs (p<0.0001). One patient developed rigors, which was considered a significant ADE (p<0.0001). Seven reactions were considered minor, which were defined as pain (3 patients), fever (1 patient), chills (1 patient), tachycardia (1 patient), and an O2 decrease of <5% (1 patient) (p<0.0148). One patient who developed a reaction with the first infusion of Gammagard Liquid tolerated a second infusion, but was switched back to Gamunex based on patient preference. The percentage of significant reactions and minor reactions was 0.6% and 4.1%, respectively.

Conclusion: There is a low incidence of significant ADE when converting patients between glycine-stabilized IVIg products.