Real-World Experiences With Facilitated Subcutaneous Immunoglobulin Substitution in Patients With Hypogammaglobulinemia, Using a Three-Step Ramp-Up Schedule

Abstract

Immunoglobulin replacement therapy with facilitated subcutaneous immunoglobulin (fSCIg) can be self-administrated at home and given at longer intervals compared to subcutaneous immunoglobulin (SCIg) therapy, but real-word experience of home-based fSCIg therapy is limited. Herein we present our real-word clinical experiences with home-based fSCIg therapy using a three-step ramp-up schedule. We registered data from all patients with immunodeficiency starting fSCIg from 01.01.2017 to 31.12.2019. For comparison we also included patients starting conventional SCIg training. Fifty-four patients followed for a median of 18 months (IQR 12, range 0–40), received fSCIg training, and 84 patients received conventional SCIg training. Out of 54 patients starting with fSCIg, 41 patients had previous experience with conventional SCIg therapy, and the main reason for starting fSCIg was ‘longer intervals between therapies’ (n=48). We found an increase in training requirement for fSCIg (3 ± 1 [2-9] days) compared to conventional SCIg (2 ± 0 [1-7] days), P< 0.001 (median ± IQR, [range]). For fSCIg training, IgG levels were stable from baseline (8.9 ± 2.3 g/L), 3-6 months (10.2 ± 2.2 g/L) and 9-12 months (9.9 ± 2.3 g/L), P= 0.11 (mean ± SD). The most common side-effect was: ‘rubor around injection site’ (n=48, 89%). No patients experienced severe adverse events (grade 3-4). Thirteen patients (24%) discontinued fSCIg therapy due to local adverse events (n=9), cognitive/psychological difficulties (n=6) and/or systemic adverse events (n=3). In conclusion, fSCIg training using a three-step ramp-up schedule is safe and well tolerated by the majority of patients, but requires longer training time compared to conventional SCIg.

A clinician’s guide for administration of high-concentration and facilitated subcutaneous immunoglobulin replacement therapy in patients with primary immunodeficiency diseases

“…Treating healthcare professionals should counsel patients that the SCIG infusion frequency may lead to more local adverse reactions. For IG-naïve patients, there are several strategies for initiating SCIG therapy [ 44 , 46 , 47 ]. These include initiation with a loading dose (SCIG or IVIG) for patients with very low IgG levels [ 44 , 46 , 47 ].…”

“…For IG-naïve patients, there are several strategies for initiating SCIG therapy [ 44 , 46 , 47 ]. These include initiation with a loading dose (SCIG or IVIG) for patients with very low IgG levels [ 44 , 46 , 47 ]. Some patients treated long-term with lower volumes of IG per site may be reluctant to try higher volumes compared with patients who started therapy with relatively higher infusion volumes per site.…”

“…Transitioning patients from IVIG to SCIG therapy, or initiating IG-naïve patients with SCIG therapy, must be initially conducted in a specialized infusion facility under the care of an experienced medical provider or by a home infusion nurse. There are multiple protocols to guide therapy for the initiating healthcare professional [ 44 , 46 , 47 ]. Patients must demonstrate the ability to self-administer SCIG therapy prior to the authorization of self-home-infusion therapy, where tolerability of SCIG therapy can be further assessed.…”

“…Knowledge of the patient’s treatment goals and expectations is important for providers as patients must receive additional guidance for managing local infusion site reactions. This is particularly crucial in patients initiating fSCIG, as recent clinical trials highlighted infusion reactions as one the primary reasons for treatment discontinuation in a small number of patients [ 44 , 45 , 52 ]. Although the number of patients was small, these dropouts occurred in highly controlled studies, with specifically selected patient populations, thorough patient training, and frequent monitoring; thus, these findings warrant consideration for patient adherence with fSCIG [ 44 , 45 , 52 ].…”

“…This is particularly crucial in patients initiating fSCIG, as recent clinical trials highlighted infusion reactions as one the primary reasons for treatment discontinuation in a small number of patients [ 44 , 45 , 52 ]. Although the number of patients was small, these dropouts occurred in highly controlled studies, with specifically selected patient populations, thorough patient training, and frequent monitoring; thus, these findings warrant consideration for patient adherence with fSCIG [ 44 , 45 , 52 ]. fSCIG initiation may require additional training and monitoring due to much higher volumes infused over a shorter timespan [ 44 , 45 ].…”