Hemolytic events after the administration of lyophilized versus liquid immune globulin: an analysis of a single manufacturer's safety database

Intravenous immunoglobulin-induced acute thrombocytopenia

BACKGROUND

Intravenous immunoglobulin (IVIG) has known efficacy in various hematologic conditions, including immune thrombocytopenic purpura.

STUDY DESIGN AND METHODS

We present the clinical course of a patient with splenic marginal zone lymphoma, who developed acute thrombocytopenia on three consecutive episodes, with nadir counts of 27 × 10⁹ , 50 × 10⁹ , and 9 × 10⁹ /L, upon administration of Intratect IVIG for hypogammaglobulinemia. An immunofluorescence test applying flow cytometry and monoclonal antibody immobilization of platelet antigens (MAIPA) assay were used to evaluate the reaction between IgG present in the IVIG preparations and the patient's or healthy donors' platelets (PLTs).

RESULTS

A strong direct binding reaction was observed between the patient's PLTs and Intratect IgG using both methods. A similar reaction failed to materialize with controls. Binding was not antigen specific according to MAIPA.

CONCLUSIONS

This is the first reported case of thrombocytopenia as a possible adverse effect of IVIG.

10% liquid human immunoglobulin (KIOVIG®) for immunomodulation in autoimmune disorders

Intravenous immunoglobulins have been used to treat autoimmune disorders (ADs) for over 50 years. The etiologies of various ADs are not fully understood and although intravenous immunoglobulin treatment has proved its immunomodulatory properties, the roles of proposed mechanisms of action also remain a matter of speculation. A systemic search of the literature regarding KIOVIG® (Baxalta US, Inc., MA, USA) use in clinical trials on patients with ADs and a detailed review of retrieved articles revealed eight relevant publications. These articles reported KIOVIG use in multifocal motor neuropathy, chronic inflammatory demyelinating polyneuropathy, idiopathic thrombocytopenic purpura, Kawasaki disease, Guillain–Barré syndrome and other autoimmune and neurologic disorders and showed that KIOVIG is an effective, safe and well-tolerated treatment in the studied populations. Nevertheless, further studies on larger patient cohorts are needed.

Demonstration of safety of intravenous immunoglobulin in geriatric patients in a long-term, placebo-controlled study of Alzheimer's disease

INTRODUCTION

We present safety results from a study of Gammagard Liquid intravenous immunoglobulin (IGIV) in patients with probable Alzheimer's disease.

METHODS

This was a placebo-controlled double-blind study. Subjects were randomized to 400 mg/kg (n = 127), 200 mg/kg (n = 135) IGIV, or to 0.25% human albumin (n = 121) administered every 2 weeks ± 7 days for 18 months.

RESULTS

Elevated risk ratios of IGIV versus placebo included chills (3.85) in 9.5% of IGIV-treated subjects (all doses), compared to 2.5% of placebo-treated subjects, and rash (3.08) in 15.3% of IGIV-treated subjects versus 5.0% of subjects treated with placebo. Subjects in the highest IGIV dose group had the lowest proportion of SAEs considered related to product (2 of 127 [1.6%]). Subjects treated with IGIV experienced a lower rate of respiratory and all other infections compared to placebo.

DISCUSSION

IGIV-treated subjects did not experience higher rates of renal failure, lung injury, or thrombotic events than the placebo group. There were no unexpected safety findings. IGIV was well tolerated throughout 18 months of treatment in subjects aged 50-89 years.

The effect of exposure misclassification in spontaneous ADR reports on the time to detection of product-specific risks for biologicals: a simulation study

BACKGROUND AND OBJECTIVE

The availability of accurate product-specific exposure information is essential in the pharmacovigilance of biologicals, because differences in the safety profile may emerge between products containing the same active substance. In spontaneous adverse drug reaction (ADR) reports, drug exposure may, however, be misclassified, that is, attributed to the incorrect product. The aim of this study was to explore the effect of exposure misclassification on the time to detection of product-specific risks in spontaneous reporting systems.

METHODS

We used data simulations to explore the effect of exposure misclassification. We simulated an active substance-specific subset of a spontaneous reporting system and used the proportional reporting ratio for signal detection. The effect of exposure misclassification was evaluated in three test cases representing product-specific ADRs that may occur for biologicals and studied in relative terms by varying the model parameters (market share and relative risk).

RESULTS

We found that exposure misclassification results in the largest delay in identification of risks that have a weak association (relative risk < 2 or 3) with the product of interest and in situations where the product associated with the unique risk has a large (>50%) market share. The absolute public health impact of exposure misclassification, in terms of cases/time to detection, varied considerably across the test cases.

CONCLUSION

Exposure misclassification in ADR reports may result in a delayed detection of product-specific risks, particularly in the detection of weak drug-event associations. Our findings can help inform the future implementation and refinement of product-specific and batch-specific signal detection procedures.