Immunoglobulin for Hypogammaglobulinemia Due to Chimeric Antigen Receptor T Cell Therapy

Chimeric antigen receptor (CAR) T cells are patient-derived T cells engineered to express a fusion protein that directs them to target a tumor-associated antigen. The tumor-associated antigen CD19 is expressed on tumor cells in these conditions as well as on healthy cells of the B cell lineage. This results the "on-target off-tumor" effect of profound B cell depletion in these patients often with attendant hypogammaglobulinemia (HGG). Serious infections are common in this patient population and represent the main cause of non-relapse related mortality in CAR T cell treated patients.

Treatment of HGG with immunoglobulin replacement therapy (IRT) is a core component of infection prevention. Standard of care IRT can be administered intravenously (IVIG) or subcutaneously (SCIG). The proposed project will investigate frequency of bacterial infections, quality of life, treatment satisfaction, and adverse events in patients treated with CAR T-cell therapy who are treated with IVIG and SCIG.

Inclusion criteria

• Age ≥18 years
• Severe HGG defined as total IgG <4 g/L (after subtracting the IgG paraprotein fraction, if present)
• Treated with CD19 targeted CAR T cell therapy in the past 6 months
• Consent to receive plasma-derived productions
• Ability to provide informed consent

Exclusion criteria

• Inability to comply with study procedures
• Pregnancy or planning to conceive
• Breastfeeding
• Protein-losing conditions that may contribute to HGG (e.g., protein-losing enteropathy, nephrotic syndrome)
• SCIG infusion in the prior 3 months.
• History of allergy or severe reactions to immune globulin productions