Subcutaneous IgG loading achieves favorable outcomes in immunodeficiency
MedWire News: Giving patients newly diagnosed with primary immunodeficiency (PI) a loading dose of subcutaneous immunoglobulin (Ig)G (SCIG) enables them to achieve rapid and sustained stabilization of IgG levels, a prospective, multicenter study shows.
The treatment provided consistent protection against infection and clear improvements in several measures of health-related quality of life (HRQL), particularly in children.
"These data may challenge the existing recommendations of an intravenous loading phase before starting SCIG therapy in previously untreated patients," Michael Borte (University of Leipzig, Germany) and colleagues comment in the Journal of Clinical Oncology.
The SCIG formulation Vivaglobin, a ready-to-use 16% IgG solution, is established as an effective and well-tolerated treatment, allowing flexibility through self-administration at home.
However, although the relatively stable IgG levels achieved with SCIG avoids drawbacks of intravenously administered IgG (ie, increased risks for adverse events and infections during IgG peaks and troughs) there is a relative delay in achieving therapeutic plasma levels with SCIG alone.
Borte et al initiated a prospective, open-label, multicenter, 6-month study to evaluate a new regimen of initiating IgG therapy with SCIG, involving a short initial period of daily subcutaneous infusions instead of initial intravenous treatment, in 18 previously untreated patients with PI.
In the loading phase, Vivaglobin SCIG at 100 mg/kg was administered daily for 5 consecutive days (total loading dose 500 mg/kg), while during the maintenance phase patients self-infused SCIG 100 mg/kg/week at home.
Borte et al report that 17 (94%) of 18 patients in the intention-to-treat population achieved the primary efficacy endpoint of IgG trough levels of 5 g/L or greater on day 12 after treatment with five daily doses of SCIG.
During the study, 34 infection episodes in 10 of 18 patients were reported, with an annualized rate of 3.95 infections per patient.
Vivaglobin SCIG treatment was well tolerated, with no related serious adverse events (AEs), although 9 (50%) patients had 58 mild AEs considered at least possibly related to Vivaglobin administration (rate 0.105 AEs per infusion).
There were also improvements in several HRQL subscales, with changes being more pronounced in children.
Discussing the findings, Borte et al say Vivaglobin SCIG "provides independence and sense of control to the patient, improves HRQL, and reduces healthcare costs and resource use."
"It is particularly suitable for children because it obviates venous access and allows integration of treatment in school and sport activities," they write.
By MedWire Reporters