Safety and Tolerability of Manual Push Administration of Subcutaneous IgPro20 at High Infusion Rates in Patients with Primary Immunodeficiency: Findings from the Manual Push Administration Cohort of the HILO Study

Infusion parameters, safety, and practical guidance for the manual administration of subcutaneous immunoglobulin 20% (Ig20Gly)

Primary immunodeficiency diseases (PIDs), also referred to as inborn errors of immunity, constitute a group of genetic conditions that affect the immune system. The current standard of care for patients with PIDs is lifelong immunoglobulin replacement therapy, delivered by intravenous (IVIG) or subcutaneous (SCIG) infusion. Immune globulin subcutaneous (human) 20% solution stabilized with glycine (Ig20Gly) is indicated as a replacement therapy for PIDs in adults and children of any age in Europe and in patients aged 2 years and above in the USA. Typically, Ig20Gly is administered using an infusion pump; however, delivery of Ig20Gly by manual administration has recently been approved in Europe. Practical recommendations on the use of Ig20Gly manual administration are lacking; this review therefore aims to provide guidance for use of this method of administration. Additionally, we summarize the infusion parameters, safety, patient-reported outcomes, and economic benefits associated with Ig20Gly manual administration. Manual administration of Ig20Gly was shown to permit faster rates of infusion than administration via infusion pump. Patients typically infused at two or fewer infusion sites with manual administration of Ig20Gly. Safety and tolerability profiles were similar for Ig20Gly manual administration and administration by infusion pump. Overall, there were comparable levels of patient satisfaction with manual administration and infusion pump, with patient preference deemed to be a key determinator of success for either method of administration. Economic studies identified cost savings for the healthcare system through manual administration compared with IVIG or SCIG infusion by infusion pump because of the reduced equipment costs and nurse support. For infusion of Ig20Gly by manual administration, a syringe and butterfly needle are used; patients are advised to start infusion at 1-2 mL/min to prevent discomfort. Overall, manual administration of Ig20Gly offers an effective and well-tolerated alternative to administration by infusion pump.

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.

Safety and Tolerability of Subcutaneous IgPro20 at High Infusion Parameters in Patients with Primary Immunodeficiency: Findings from the Pump-Assisted Administration Cohorts of the HILO Study

PURPOSE

To evaluate the safety and tolerability of subcutaneous IgPro20 (Hizentra^®, CSL Behring, King of Prussia, PA, USA) administered at high infusion parameters (> 25 mL and > 25 mL/h per injection site) in patients with primary immunodeficiency.

METHODS

The Hizentra^® Label Optimization (HILO) study was an open-label, parallel-arm, non-randomized study (NCT03033745) of IgPro20 using a forced upward titration design for infusion parameters. Patients experienced with pump-assisted IgPro20 infusions received weekly IgPro20 infusions at a stable dose in the Pump-Assisted Volume Cohort (N = 15; 25-50 mL per injection site) and in the Pump-Assisted Flow Rate Cohort (N = 18; 25-100 mL/h per injection site). Responder rates (percentage of patients who successfully completed ≥ 75% of planned infusions), safety outcomes, and serum immunoglobulin G (IgG) trough levels were evaluated.

RESULTS

Responder rates were 86.7% (13/15, 25 mL) and 73.3% (11/15, 40 and 50 mL) in the Volume Cohort, and 77.8% (14/18, 25 and 50 mL/h), 66.7% (12/18, 75 mL/h), and 61.1% (11/18, 100 mL/h) in the Flow Rate Cohort. Infusion compliance was ≥ 90% in all patients in the Volume Cohort and in 83.3% of patients in the Flow Rate Cohort. The number of injection sites (Volume Cohort) and the infusion duration (Flow Rate Cohort) decreased with increasing infusion parameters. The rate of treatment-emergent adverse events per infusion was low (0.138 [Volume Cohort] and 0.216 [Flow Rate Cohort]). Serum IgG levels remained stable during the study.

CONCLUSION

Pump-assisted IgPro20 infusions are feasible at 50 mL and 100 mL/h per injection site in treatment-experienced patients, which may result in fewer injection sites and shorter infusion times.

TRIAL REGISTRATION

NCT03033745 ; registered January 27, 2017.