Most primary immunodeficiency diseases (PIDDs) resulting in antibody deficiency require intravenous or subcutaneous immunoglobulin G (SCIG) replacement therapy. The flow and distribution of SCIG to the vasculature is impeded by the glycosaminoglycan hyaluronan in the extracellular matrix, which limits the infusion rate and volume per site, necessitating frequent infusions and multiple infusion sites. Hyaluronidase depolymerizes hyaluronan and is a spreading factor for injectable biologics. Recombinant human hyaluronidase (rHuPH20) increases SCIG absorption and dispersion. In patients with PIDD, SCIG facilitated with rHuPH20 (IGHy) has been shown to prevent infections, be well-tolerated and reduce infusion frequency and number of infusion sites as compared with conventional SCIG. This article reviews IGHy clinical studies and real-world practice data in patients with PIDD.
Keywords: immunoglobulin; intravenous administration of immunoglobulin; primary immunodeficiency disease; rHuPH20-facilitated subcutaneous infusion of IG; recombinant human hyaluronidase; subcutaneous administration of immunoglobulin.