Immunoglobulin therapies for primary immunodeficiency diseases (part 2): considerations for dosing strategies.

Immunoglobulin G (IgG) dosing in treating primary immunodeficiency diseases (PIDs) is individualized, which often involves regular monitoring of IgG levels, and considers patient experiences with immunoglobulin therapies, their clinical status and physician judgment. The frequency and dose(s) of intravenously (IVIG) and subcutaneously (SCIG) administered IgGs (including hyaluronidase-facilitated SCIG) require rigorous evaluation to maximize therapeutic benefits. Monitoring serum IgG levels represents an integral part of diagnosing primary immunodeficiency diseases and determining or adjusting IgG dosing strategies to meet individual patient needs, but cannot be conducted in isolation. This review discusses the current state and future perspectives on dosing strategies for different types of IgG therapies, as well as dosing considerations for specific patient populations, immunoglobulin-naive patients and patients switching between IVIG and SCIG.