Safety and efficacy of subcutaneous human immunoglobulin in children with primary immunodeficiency

Health-related quality of life in patients with inborn errors of immunity: A systematic review and meta-analysis

BACKGROUND

Inborn Errors of Immunity (IEI) significantly affect patients' health-related quality of life (HRQOL), presenting greater challenges than those faced by the healthy population and other chronic disease sufferers. Current research lacks comprehensive integration of this critical issue.

OBJECTIVE

This study explores HRQOL in IEI patients, identifies impacting factors, and advocates for increased research focus on their quality of life.

METHODS

Following systematic review and meta-analysis guidelines, a search of Scopus and PubMed until November 15, 2023, yielded 1633 publications. We evaluated the literature, assessed study quality, and compared the HRQOL of IEI patients to that of healthy individuals and other chronic disease patients.

RESULTS

Of 90 articles and 10,971 IEI patients analyzed, study quality varied (nine good, 63 moderate, and 18 poor). The Short Form-36 (SF-36) and Pediatric Quality of Life Inventory generic core scales (PedsQL) were the primary generic instruments used among adults and children, respectively, with 12 studies each using the disease-specific instruments. Meta-analysis showed IEI patients have significantly lower scores in general health, physical and mental health, and social and emotional roles compared to healthy populations. We noted significant differences between self and proxy reports, indicating caregiver anxiety and perception disparities.

CONCLUSION

Despite limitations like small sample sizes and reliance on generic instruments, this research underscores the substantially lower HRQOL among IEI patients, emphasizing the need for a patient-centered, multidisciplinary approach to improve their life quality and calling for more focused attention on IEI patients and their caregivers' HRQOL.

Quality of Life Evaluation in Saudi Arabian Pediatric Patients with Primary Immunodeficiency Diseases Receiving 20% Subcutaneous IgG Infusions at Home

BACKGROUND AND AIMS

Subcutaneous immunoglobulin (SCIG) home infusion is widely used as an alternative to intravenous immunoglobulin (IVIG). This study aimed to determine the quality of life (QoL) of patients with primary immunodeficiency (PID) after switching to home-based SCIG.

METHODS

In this prospective open-label single-center study, QoL was determined using the validated Arabic version of the Child Health Questionnaire at baseline and 3 and 6 months after switching from IVIG to SCIG.

RESULTS

Twenty-four patients were recruited from July 2018 to August 2021, including 14 females and 10 males. The median age of the patients was 5 years (range, 0-14 years). The patients' diagnoses included severe combined immunodeficiency, combined immunodeficiency, agammaglobulinemia, Omenn syndrome, immunodysregulation, hyper-IgE syndrome, common variable immunodeficiency, and bare lymphocyte syndrome. The median duration on IVIG before inclusion was 40 months (range, 5-125 months). The QoL score showed a significant improvement in the patients' global health at 3 and 6 months compared with those at baseline and a significant improvement in the patients' general health at 3 and 6 months compared with that at baseline. The mean baseline serum IgG trough level was 8.8 ± 2.1 g/L. The mean serum IgG level was significantly higher on SCIG at both 3 and 6 months (11.7 ± 2.3 and 11.7 ± 2.5 g/L, respectively).

CONCLUSIONS

This is the first study involving an Arab population to show improvement in the QoL of patients with PID after switching from hospital-based IVIG to home-based 20% SCIG.

Subcutaneous immunoglobulin 16.5% for the treatment of pediatric patients with primary antibody immunodeficiency

INTRODUCTION

Human immunoglobulin (IG) administered intravenously (IVIG) or subcutaneously (SCIG) is used to prevent infections in patients with primary immunodeficiency diseases (PIDDs) such as primary antibody immunodeficiencies.

AREAS COVERED

This review provides an overview of PIDD with a focus on SCIG treatment, including the properties and clinical trial results of a new SCIG 16.5% (Cutaquig, Octapharma) in pediatric patients. We also discuss the various benefits of SCIG including stable serum immunoglobulin G levels, high tolerability with fewer systemic side effects, and the flexibility of self-administration.

EXPERT OPINION

Individualized treatment for PIDD in children is necessary given the different factors that affect administration of SCIG. Variables such as the dose, dosing interval, administration sites, and ancillary equipment can be adjusted to impact the long-term satisfaction with SCIG administration in pediatric patients. The successful work that has been conducted by both professional and patient organizations to increase awareness of PIDD, especially in pediatric patients, is substantial and ongoing. The importance of early diagnosis and treatment in the pediatric patient population cannot be overstated. The safety, efficacy, and tolerability of SCIG 16.5% have been demonstrated in pediatric patients with PIDDs providing an additional therapeutic option in this vulnerable population.

British Society for Immunology and United Kingdom Primary Immunodeficiency Network (UKPIN) consensus guideline for the management of immunoglobulin replacement therapy

Currently, there is no guideline to support the use of immunoglobulin replacement therapy (IgRT) in primary and secondary immunodeficiency disorders in UK. The UK Primary Immunodeficiency Network (UK-PIN) and the British Society of Immunology (BSI) joined forces to address this need. Given the paucity of evidence, a modified Delphi approach was used covering statements for the initiation, monitoring, discontinuation of IgRT as well as home therapy programme. A group of six consultant immunologists and three nurse specialists created the statements, reviewed responses and feedback and agreed on final recommendations. This guideline includes 22 statements for initiation, 22 statements for monitoring, 11 statement for home therapy, and 19 statements for discontinuation of IgRT. Further areas of research are proposed to improve future delivery of care.

Overview of subcutaneous immunoglobulin 16.5% in primary and secondary immunodeficiency diseases

Most primary immunodeficiency diseases, and select secondary immunodeficiency diseases, are treated with immunoglobulin (IG) therapy, administered intravenously or subcutaneously (SCIG). The first instance of IG replacement for primary immunodeficiency disease was a 16.5% formulation administered subcutaneously in 1952. While most SCIG products are now a 10 or 20% concentration, this review will focus on SCIG 16.5% products with a historical overview of development, including the early pioneers who initiated and refined IG replacement therapy, as well as key characteristics, manufacturing and clinical studies. In determining an appropriate IG regimen, one must consider specific patient needs, characteristics and preferences. There are advantages to SCIG, such as stable serum immunoglobulin G levels, high tolerability and the flexibility of self-administered home treatment.

Long-Term Experience of Subcutaneous Immunoglobulin Therapy in Pediatric Primary Immunodeficient Patients with Low and Normal Body Weight

PURPOSE

The aim was to review the compliance, side effects and effectiveness of subcutaneous immunoglobulin (SCIG) supplementation in patients with primary immunodeficiencies (PID) who had previously received intravenous immunoglobulin (IVIG) therapy and subsequently switched to SCIG, as well as to compare these parameters in patients while considering body weight.

METHODS

Demographic data, clinical and laboratory findings, SCIG dose, and side effects of 87 patients were retrospectively obtained from patient files. In patients who first received IVIG and then SCIG, the monthly SCIG dose was calculated by multiplying the IVIG dose by 1.37. The total monthly SCIG dose was distributed via injection across three or four doses per month, thus every 7 or 10 days.

RESULTS

Of the 87 patients aged between one and 22 years, 50 were male (57.5%) and 37 were female (42.5%). The serum IgG levels of the SCIG group were higher and more stable than those of the IVIG group. The number of hospitalizations and infections decreased significantly after initiation of SCIG. Thirteen patients (14.9%) had low body weight (LBW) for their age, seven of whom were male (53.8%). Serum IgG levels of the LBW cohort were significantly elevated and more stable during the SCIG period than the IVIG period. Mild, local side effects were detected in 153 administrations (3.3%) in 30 patients with normal body weight, while no local reactions were recorded in the patients with LBW.

CONCLUSION

SCIG supplementation is an effective treatment for pediatric patients with PID. The preliminary data from the present study suggest that such treatment is also safe for LBW children. The numbers of patient hospitalizations and family visits to clinics were reduced, allowing our patients and their parents to live more normal lives.

Patient Preferences for Subcutaneous versus Intravenous Administration of Treatment for Chronic Immune System Disorders: A Systematic Review

BACKGROUND

For many chronic immune system disorders, the available treatments provide several options for route of administration. The objective of this systematic literature review is to inform discussions about therapy choices for individual patients by summarizing the available evidence regarding the preferences of patients with chronic immune system disorders for intravenous (IV) or subcutaneous (SC) administration.

METHODS

Searches of the MEDLINE, Embase and Cochrane Library databases were conducted using terms designed to capture studies reporting patient preferences between IV and SC therapy published in English. Relevant studies were limited to those in which mode of administration, including treatment frequency and setting, was the main difference between comparators.

RESULTS

In total, 49 studies were included in the review. Among 18 studies that compared IV and SC immunoglobulin therapy, 16 found patients to prefer the SC administration route. The results of the 31 studies comparing IV infusion and SC injection of non-immunoglobulin therapies were mixed, with patients favoring SC administration in 20, IV infusion in seven, and having no overall preference in four. Patient experience had a strong effect on preferences, with treatment-experienced patients preferring their current administration route in most studies. Patients preferring SC administration tended also to prefer treatment at home, mainly due to the convenience and comfort of home treatment and the avoidance of having to attend hospital. By contrast, patients preferring IV infusion tended to cite the lower treatment frequency and a dislike of self-injecting, and preferred hospital treatment, mainly due to the presence of healthcare professionals and resulting feelings of safety.

CONCLUSION

In general patients with chronic immune system disorders tend to be more likely to choose SC administration than IV infusion, but preferences may vary according among individuals. These findings may assist discussions around appropriate treatment choices for each patient.

Patient experience with subcutaneous immunoglobulin 20%, Ig20Gly, for primary immunodeficiency diseases: a prespecified post hoc analysis of combined data from 2 pivotal trials

BACKGROUND

Often, patients with primary immunodeficiency diseases (PID), which are marked by the absence or loss of functional antibodies, require lifelong treatment with immunoglobulin (IG) replacement therapy administered either intravenously (intravenous immunoglobulin [IVIG]) or subcutaneously (subcutaneous immunoglobulin [SCIG]). In patients with PID, the 20% SCIG product, Ig20Gly, was shown to be efficacious and well tolerated in 2 phase 2/3 trials conducted in North America and Europe. This analysis evaluated patient satisfaction with Ig20Gly therapy and treatment preferences.

METHODS

This prespecified post hoc analysis showed combined data from 2 Ig20Gly pivotal trials. Treatment satisfaction was assessed in the pre-Ig20Gly period and after ≥11 months of Ig20Gly treatment using the Life Quality Index (LQI; both studies) and the Treatment Satisfaction Questionnaire for Medication-9 (TSQM-9; North American study only). Treatment preference was assessed using a survey at the end of the European study. Median within-patient differences in LQI and TSQM-9 scores between the pre-Ig20Gly period and the end of the Ig20Gly treatment period were assessed using the Wilcoxon signed-rank test.

RESULTS

A total of 113 patients (n = 68 [North American]; n = 45 [Europe]) with PID were included in the analysis. In the combined LQI analysis (n = 110), significant improvements were observed in the treatment interference (median ∆: + 2.8; P = 0.006) and therapy setting (median ∆: + 5.6; P < 0.0001) domains, and in the item-level scores for convenience (median ∆: + 1.0; P < 0.0001) and interference with work/school (median ∆: + 1.0; P = 0.0001) categories. In the subgroup analyses, significant improvements in the treatment interference and therapy setting domains and the convenience and interference with work/school items were observed for those who had previously received treatment outside the home, those who had previously received IVIG, and those in the North American study. Significant improvements were observed in the TSQM-9 treatment convenience domain (median ∆: + 11.1; P < 0.0001) and selected item-level scores in the North American study. In the European study, most (88.9%) patients preferred to continue Ig20Gly versus other IG treatments.

CONCLUSIONS

After ≥11 months of taking Ig20Gly, patients reported high levels of treatment satisfaction, convenience, and preference for Ig20Gly, with consistent results across studies and use of multiple patient-reported outcome measures.

Primary immunodeficiency disease: a cost-utility analysis comparing intravenous vs subcutaneous immunoglobulin replacement therapy in Australia

BACKGROUND

Hospital-based intravenous immunoglobulin (IVIg) treatment has been the standard treatment mode for patients with primary immunodeficiency disease (PID). With the newer home-based subcutaneous immunoglobulin (SCIg) becoming approved for use in most countries, the question arises as to whether SCIg is a cost-effective treatment mode compared to IVIg in Australia.

MATERIALS AND METHODS

We developed a Markov cohort simulation model with six health states: PID without infection, PID with infection treated at home or hospital, bronchiectasis without infection, bronchiectasis with infection treated at home or hospital, bronchiectasis with chronic Pseudomonas aeruginosa infection, and death, from an Australian healthcare system perspective. A 10-year time horizon with weekly cycles was chosen, and the expected costs and quality-adjusted life-years (QALYs) of the two treatment options estimated.

RESULTS

The cumulative 10-year cost per patient was 297,547 Australian dollars (A$) with IVIg and A$ 251,713 for SCIg. IVIg resulted in 5.55 QALYs and SCIg 5.57 QALYs. Thus, SCIg appears to be a cost-saving option and possibly improves QALY from the Australian healthcare system perspective (i.e., the dominant treatment option). A probabilistic sensitivity analysis showed that the SCIg option is preferred in 93.2% of simulations given willingness to pay of A$ 50,000 per QALY gained.

DISCUSSION

The results suggest that home-based SCIg is a cost-effective treatment option for patients with PID in Queensland, Australia.

Health-Related Quality of Life in Children and Adults with Primary Immunodeficiencies: A Systematic Review and Meta-Analysis

BACKGROUND

Primary immunodeficiency diseases (PIDs) are a group of diseases that have been found to have an adverse impact on quality of life and health-related quality of life (HRQOL).

OBJECTIVE

To systematically assess available evidence on the HRQOL of patients with PID.

METHODS

We performed a literature search of all studies reporting HRQOL assessments in patients with PID published in English from inception to April 11, 2017, using MEDLINE and EMBASE.

RESULTS

Of 1699 articles, 37 met the inclusion criteria. HRQOL was assessed by using various generic instruments. Child Health Questionnaire - Parent Form 50 and short-form 36 were the most frequently used (for children and adults, respectively). No PID-specific HRQOL instruments were used for children. HRQOL is significantly lower in adults with PID (mean score difference, -24.46; 95% CI, -34.57 to -14.34) and children (-10.06; 95% CI, -12.95 to -7.17) compared with the reference population and lower than in patients with other chronic conditions. There is a general agreement between child- and parent-reported data, although parents report child school-related HRQOL as more impaired than do children (6.19; 95% CI, 0.38 to 11.99). Most studies were of low to moderate quality and had methodological limitations.

CONCLUSIONS

Available evidence suggests that patients with PID have a lower HRQOL than do healthy individuals and patients with other chronic conditions, including diabetes mellitus and juvenile idiopathic arthritis. No disease-specific instruments are available for children, and few options are available for adults. This finding highlights the need for developing PID-specific instruments that would allow for a more sensitive evaluation of PID impact on patient health and psychological well-being, school/work, and social activities.

Efficacy, safety and quality of life in patients receiving subcutaneous IgG treatment: experience in Bogotá, Colombia

AIM

Investigate efficacy, safety and quality of life of Gammanorm^® 16.5% (subcutaneous immunoglobulin [SCIG]) in patients with primary immunodeficiencies (PIDs) and safety and to lesser extent efficacy in autoimmune diseases.

PATIENTS & METHODS

Medical records were extracted from 31 pediatric and 12 adult patients who received SCIG as part of the Personalized Program at University Children's Hospital, Bogotá, Colombia.

RESULTS

Mean SCIG dose was 28.7 g/month. Serious bacterial infections were observed in 7/33 patients in the PID group, most often bacterial pneumonia (3/33). There were no serious adverse events related to SCIG treatment. Drug-related adverse reactions were reported in 2/43 patients.

CONCLUSION

Self-administration of SCIG provided effective protection, favorable tolerability and improved quality of life in patients with PIDs and autoimmune diseases from Colombia.

II Brazilian Consensus on the use of human immunoglobulin in patients with primary immunodeficiencies

In the last few years, new primary immunodeficiencies and genetic defects have been described. Recently, immunoglobulin products with improved compositions and for subcutaneous use have become available in Brazil. In order to guide physicians on the use of human immunoglobulin to treat primary immunodeficiencies, based on a narrative literature review and their professional experience, the members of the Primary Immunodeficiency Group of the Brazilian Society of Allergy and Immunology prepared an updated document of the 1^st Brazilian Consensus, published in 2010. The document presents new knowledge about the indications and efficacy of immunoglobulin therapy in primary immunodeficiencies, relevant production-related aspects, mode of use (routes of administration, pharmacokinetics, doses and intervals), adverse events (major, prevention, treatment and reporting), patient monitoring, presentations available and how to have access to this therapeutic resource in Brazil.

Quality of Life, Treatment Beliefs, and Treatment Satisfaction in Children Treated for Primary Immunodeficiency with SCIg

Despite the development of subcutaneous treatment, children and adolescents with primary immunodeficiency (PID) are vulnerable to a lower quality of life (QoL) than non-clinical participants. Comparisons have been offered in rare reports with limited sample sizes. No description is available of treatment beliefs and treatment satisfaction with standard tools. The objective of this study was to describe a large sample of patients with pediatric PID on QoL, treatment beliefs and satisfaction, and identify perceived benefits and issues of treatment both in children and parents. A mail-back survey was conducted in 60 patients with PID treated with subcutaneous Ig and their parents from a clinic in Montreal (QC, Canada). We used the standardized tools to assess for QoL levels, beliefs of necessity and concerns with treatment, and dimensions of satisfaction. We collected and coded perceived benefits and issues through open-ended questions. We found lower QoL in children with PID than in healthy non-clinical participants (median d = 0.40) and similar QoL levels to children with cancer (median d = 0.12). Participants considered their treatment as less necessary and able to control the illness and less convenient than patients with other conditions. Children were more prone to consider the treatment as convenient (69 vs. 47% p = .028) but reported more discomfort (24 vs. 10% p = .043) than parents. Results suggest a lower-than-expected QoL in pediatric PID. Aspects of the illness and treatment are probably unclear to patients and their families, as necessity beliefs were lower than expected. Educational strategies should be developed and assessed to address this issue.

A cohort of French pediatric patients with primary immunodeficiencies: are patient preferences regarding replacement immunotherapy fulfilled in real-life conditions?

OBJECTIVE

To assess quality of life and satisfaction regarding immunoglobulin-replacement therapy (IgRT) treatment according to the route (intravenous Ig [IVIg] or subcutaneous Ig [SCIg]) and place of administration (home-based IgRT or hospital-based IgRT).

SUBJECTS AND METHODS

Children 5-15 years old treated for primary immunodeficiency disease (PIDD) with IgRT for ≥3 months were included in a prospective, noninterventional cohort study and followed over 12 months. Quality of life was assessed with the Child Health Questionnaire - parent form (CHQ-PF)-50 questionnaire. Satisfaction with IgRT was measured with a three-dimensional scale (Life Quality Index [LQI] with three components: factor I [F_I], treatment interference; F_II, therapy-related problems; F_III, therapy settings).

RESULTS

A total of 44 children (9.7±3.2 years old) receiving IgRT for a mean of 5.6±4.5 years (median 4.1 years) entered the study: 18 (40.9%) were receiving hospital-based IVIg, two (4.6%) were receiving home-based IVIg, and 24 (54.6%) were treated by home-based SCIg. LQI F_III was higher for home-based SCIg than for hospital-based IVIg (P=0.0003), but there was no difference for LQI F_I or LQI F_II. LQI F_III significantly improved in five patients who switched from IVIg to SCIg during the follow-up when compared to patients who pursued the same regimen (either IVIg or SCIg). No difference was found on CHQ-PF50 subscales, LQI F_I, or LQI F_II.

CONCLUSION

Home-based SCIg gave higher satisfaction regarding therapy settings than hospital-based IVIg. No difference was found on other subscales of the LQI or CHQ-PF50 between hospital-based IVIG and home-based SCIG.

Update on the use of immunoglobulin in human disease: A review of evidence

Human immunoglobulin preparations for intravenous or subcutaneous administration are the cornerstone of treatment in patients with primary immunodeficiency diseases affecting the humoral immune system. Intravenous preparations have a number of important uses in the treatment of other diseases in humans as well, some for which acceptable treatment alternatives do not exist. We provide an update of the evidence-based guideline on immunoglobulin therapy, last published in 2006. Given the potential risks and inherent scarcity of human immunoglobulin, careful consideration of its indications and administration is warranted.

Does the route of immunoglobin replacement therapy impact quality of life and satisfaction in patients with primary immunodeficiency? Insights from the French cohort "Visages"

Background

IgG replacement therapy (IgRT) in primary immunodeficiencies (PID) is a lifelong treatment which may be administered intravenously (IVIg) or subcutaneously (SCIg), at hospital or at home. The objective of the VISAGE study was to investigate if route and/or place for IgRT impact patients’ satisfaction regarding IgRT and quality of life (QoL) in real-life conditions.

Methods

The study enrolled PID patients at least 15 years old receiving IgRT for at least 3 months. Satisfaction and QoL were evaluated at enrollment and over a 12-month follow-up period by Life Quality Index (LQI) which measures 3 dimensions of satisfaction: treatment interference, therapy related problems and therapy settings (factors I, II and III) and SF-36 v2 questionnaire.

Results

The study included 116 PID patients (mean age 42 ± 18 years, 44 % males, 58 % with scholar or professional occupation) receiving IgRT for a mean of 8.5 ± 8.4 years. At enrollment they were receiving either home-based SCIg (51 %), hospital-based IVIg (40 %) or home-based IVIg (9 %). Patients exhibited a high degree of satisfaction regarding IgRT whatever the route and place for administration. LQI factor I was higher for home-based SCIg (86 ± 2) than for hospital-based IVIg (81 ± 3) and home-based IVIg (73 ± 5; p = 0.02 versus home-based SCIg); no difference was found for LQI factor II; LQI factor III was higher for home-based SCIg (92 ± 2) than for hospital-based IVIg (87 ± 5) and hospital-based IVIg (82 ± 3; p = 0.005 versus home-based SCIg). By contrast, every dimension of QoL was impaired. Over the follow-up period, 10 patients switched from hospital-based IVIg to home-based SCIg and improved LQI factor I (p = 0.004) and factor III (p = 0.02), while no change was noticed in LQI factors II and QoL. Meanwhile, no change in satisfaction or QoL was found in patients with stable route of IgRT. When asked on their preferred place of treatment all but one patient with home-based treatment would choose to be treated at home and 29 % of patients treated at hospital would prefer home-based IgRT.

Conclusion

PID patients expressed a high degree of satisfaction regarding IgRT, contrasting with impaired QoL. In real-life conditions awareness of patient’s expectations regarding the route or place of IgRT may be associated with further improvement of satisfaction.

Long-Term Tolerability, Safety, and Efficacy of Recombinant Human Hyaluronidase-Facilitated Subcutaneous Infusion of Human Immunoglobulin for Primary Immunodeficiency

Purpose

Treatment of primary immunodeficiency diseases (PIDD) with subcutaneous (SC) infusions of IgG preceded by injection of recombinant human hyaluronidase (rHuPH20) (IGHy) to increase SC tissue permeability was evaluated in two consecutive, prospective, non-controlled, multi-center studies.

Methods

Subjects >4 years of age received SC IgG replacement at a weekly dose equivalent of 108 % of their previous intravenous (IV) dose, facilitated by prior injection of 75 U/g IgG of rHuPH20. Starting with weekly SC infusions, the interval was increased (ramped-up) to a 3- or 4-week schedule.

Results

Eighty-three subjects (24 < 18 years; 59 ≥ 18 years) received 2729 infusions (excluding ramp-up) at a mean dose of 0.155 g/kg/week in the pivotal and 0.156 g/kg/week in the extension study. IGHy exposure exceeded 30 months in 48 subjects.

During 187.7 subject-years of IGHy exposure, 2005 adverse events (AEs) (10.68 per subject-year) occurred. The rate of related systemic AEs during consecutive 1-year periods remained low; the rate of related local AEs decreased from 3.68/subject-year in months 1–12 to approximately 1.50/subject-year after 30 months of treatment. Fifteen subjects transiently developed anti-rHuPH20 binding antibody. There was no difference in AE rates in these subjects before and after the first titer increase to ≥1:160.

The rate of infections during IGHy exposure was 2.99 per subject-year and did not increase during the studies. Annual infection rates were 3.02 in subjects <18 years and 2.98 in subjects ≥18 years.

Conclusions

Long-term replacement therapy with IGHy was safe and effective in 83 pediatric and adult subjects with PIDD.

Electronic supplementary material

The online version of this article (doi:10.1007/s10875-016-0298-x) contains supplementary material, which is available to authorized users.

Clinical experiences in primary and secondary immunodeficiencies and immune-mediated conditions using Gammanorm(®)

Treatment for primary and secondary immunodeficiency disorders focuses on prevention and management of infections, using immunoglobulin G (IgG) replacement therapy with regular intravenous or subcutaneous IgG (SCIG) infusions. SCIG therapy has many advantages including improved efficacy and tolerability, enhanced patient satisfaction and lower costs. A number of SCIG preparations are available, including Gammanorm(®) (Octapharma AG), a ready-to-use 16.5% liquid preparation of IgG, with low viscosity, well suited to self-administration and a long history of use. Clinical experience with Gammanorm has shown that it is effective and well tolerated in children and adults, including pregnant women, for primary and secondary immunodeficiency disorders. Recent data also suggest SCIG may have a role in the treatment of certain immune-mediated conditions.

A Comparative Study of Intravenous Immunoglobulin and Subcutaneous Immunoglobulin in Adult Patients with Primary Immunodeficiency Diseases: A Systematic Review and Meta-Analysis

Subcutaneous immunoglobulin (SCIG) is a new therapeutic procedure for patients with primary immunodeficiency (PI). This research is a systematic review of studies on the efficacy and safety of intravenous immunoglobulin (IVIG) and SCIG in adult patients with PI. This study includes a systematic review of cohorts and randomized clinical trials (24 articles) from 5 databases with no time limits. Random effects meta-analysis was performed for outcomes such as efficacy and safety. Standard mean difference (SMD) of serum immunoglobulin level was equal to 0.336 (P <0.01; 0.205-0.467) and the odds ratio (OR) of side effects was 0.497 (P=0.1; 0.180-1.371). The results indicate that SCIG leads to a higher level of immunoglobulin and a reduction in side effects but shows the same infection rate as IVIG. Our analysis shows that shifting from IVIG to SCIG therapy can have clinical benefits for PI patients.

Health-related quality of life in patients with primary immunodeficiency disease

Primary immunodeficiency disease (PIDD) with hypogammaglobulinemia is characterized by recurrent and severe bacterial infections and IgG replacement is the standard of care in many of these patients. Health-related quality of life (HRQOL) is becoming increasingly recognized as a factor that affects patient well-being and treatment preferences. In an effort to better understand what factors affect HRQOL in patients with PIDD, we reviewed the published literature that used standardized instruments for the measurement of HRQOL. We investigated HRQOL in PIDD patients compared with normal controls and patients with other chronic diseases; we also investigated the impact of treatment administration on patient satisfaction. The most commonly encountered health-related quality of life instruments were the child heath questionnaire parental form 50, short form 36, PedsQL 4.0, Lansky's play performance scale, and Life Quality Index. Patients with PIDD scored significantly lower on many of the instruments compared with normal controls. Also, while it appears that many patients appreciate home-based and subcutaneous IgG replacement therapy, patient satisfaction ultimately involves various clinical factors and individual patient preferences. By further analyzing what factors impact HRQOL, therapy adjustments can be made to maximize patient well-being and minimize disease impact on daily functioning.

Management of adverse events in the treatment of patients with immunoglobulin therapy: A review of evidence

Immunoglobulin (IG) therapy is actually used for a broad range of diseases including primary and secondary immunodeficiency disorders, and autoimmune diseases. This therapy is available for intravenous (IV) and subcutaneous (SC) administration. The efficacy of the IG therapy has been demonstrated in numerous studies and across different diseases. Generally, IG infusions are well tolerated; however some well-known adverse reactions, ranging from mild to severe, are associated with the therapy. The most common adverse reactions including headache, nausea, myalgia, fever, chills, chest discomfort, skin and anaphylactic reactions, could arise immediately during or after the infusion. Delayed events could be more severe and include migraine headaches, aseptic meningitis, haemolysis renal impairment and thrombotic events. This paper reviews all the potential adverse events related to IG therapy and establishes a comprehensive guideline for the management of these events. Moreover it resumes the opinions and clinical experience of expert endorsers on the utilization of the treatment. Published data were classified into levels of evidence and the strength of the recommendation was given for each intervention according to the GRADE system.

Current treatment options with immunoglobulin G for the individualization of care in patients with primary immunodeficiency disease

Primary antibody deficiencies require lifelong replacement therapy with immunoglobulin (Ig)G to reduce the incidence and severity of infections. Both subcutaneous and intravenous routes of administering IgG can be effective and well tolerated. Treatment regimens can be individualized to provide optimal medical and quality-of-life outcomes in infants, children, adults and elderly people. Frequency, dose, route of administration, home or infusion-centre administration, and the use of self- or health-professional-administered infusion can be tailored to suit individual patient needs and circumstances. Patient education is needed to understand the disease and the importance of continuous therapy. Both the subcutaneous and intravenous routes have advantages and disadvantages, which should be considered in selecting each patient's treatment regimen. The subcutaneous route is attractive to many patients because of a reduced incidence of systemic adverse events, flexibility in scheduling and its comparative ease of administration, at home or in a clinic. Self-infusion regimens, however, require independence and self-reliance, good compliance on the part of the patient/parent and the confidence of the physician and the nurse. Intravenous administration in a clinic setting may be more appropriate in patients with reduced manual dexterity, reluctance to self-administer or a lack of self-reliance, and intravenous administration at home for those with good venous access who prefer less frequent treatments. Both therapy approaches have been demonstrated to provide protection from infections and improve health-related quality of life. Data supporting current options in IgG replacement are presented, and considerations in choosing between the two routes of therapy are discussed.

20% subcutaneous immunoglobulin for patients with primary immunodeficiency diseases: A systematic review

BACKGROUND

Primary immunodeficiency diseases (PID) are a group of rare disorders that patients do not have normal function of the immune system. Subcutaneous immunoglobulin 20% (SCIG-20%) was a candidate when considering replacement therapy with immunoglobulin in PID, but the evidence was not clear. To understand and interpret the available evidence, we conducted a systematic review to assess the efficacy and safety of SCIG-20% for patients with PID.

METHOD

Literature searches were conducted in PUBMED, EMBASE, Cochrane Library, CBM, VIP, CNKI, WanFang, LILACS and U.S. ClinicalTrials.gov. Clinical studies published in full text that met predefined inclusion criteria were eligible irrespective of language. Reviewers independently assessed all potential studies and extracted data. The fixed-effect model was used in meta-analysis.

RESULTS

4 studies involving 100 patients were included. The pooled rate of infection was 0.80 with the annual rate of 3.74. 38% patients missed days from work/school and annual rate was 4.54days in one year per patient. Only 4% patients were hospitalized due to infection and it costs 1.57days in one year per patient. 70% patients used antibiotics during 58.4days in one year per patient. 80 patients (80.0%) who experienced 1630 AEs were considered related to SCIG-20%. Only 7 related AEs were severe, of which, 4 were local reactions and 3 were headaches. Studies on health related quality of life and satisfaction suggested that patients with SCIG-20% had a good life quality and satisfied with SCIG treatment.

CONCLUSIONS

SCIG-20% treatment was not recommended for patients with primary immunodeficiency. Low quality of each outcome suggested that the evidence on effect of SCIG-20% for patients with PID is inadequate. Further comparative studies are urgently needed, especially in comparison with IVIG or SCIG of other concentrations.

Subcutaneous immunoglobulin replacement therapy: the European experience

PURPOSE OF REVIEW

Rapid subcutaneous immunoglobulin (SCIg) infusions have been used as an important method of delivering replacement immunoglobulin (Ig) to patients with primary immune deficiencies (PIDs) in Europe over the last 25 years. This review provides a comprehensive interpretation of the literature relating to the administration of SCIg and the services that have been developed alongside.

RECENT FINDINGS

Using rates of at least 20 ml/h per infusion site and simultaneous sites, the infusion time once per week is short (1-2 h in adults) and using small portable pumps, the child or adult is free for other activities during the therapy. The rapid SCIg infusions have been documented as well tolerated, efficacious and acceptable to infants and their parents, children, adults and elderly patients, and more recently to patients with autoimmunity requiring immunomodulatory Ig doses.

SUMMARY

As part of PID diagnostic and management services, educational programmes for self-infusion of both intravenous Ig and SCIg at home have been developed throughout Europe, resulting in increased patient compliance and patient empowerment as well as cost-savings for healthcare providers.

Dose-related regulatory effect of intravenous immunoglobulin on dendritic cells-mediated immune response

CONTEXT

Intravenous immunoglobulin (IVIG) has been successfully applied in immune-related diseases of adults and neonates, such as human immunodeficiency virus (HIV) infection and systemic lupus erythematosus (SLE).

OBJECTIVE

This study aims to investigate the distinct impacts of IVIG on cultured dendritic cells (DCs) from newborn and healthy adult.

MATERIALS AND METHODS

Blood samples were collected from eight full-term newborns and eight healthy adult volunteers. DCs from cord blood and peripheral blood were both cultured in the RPMI 1640 medium containing 10% fetal calf serum, 50 ng/ml granulocyte/macrophage colony-stimulating factor (GM-CSF) and 10 ng/ml recombinant human interleukin-4 (rhIL-4) for 5 d with therapeutic IVIG (20 mg/ml) or physiological IVIG (10 mg/ml). Lipopolysaccharides (LPSs, 1 μg/ml) were added on the fifth day to induce the maturation of immature DCs. The phagocytosis of monocytes, expression of MR (mannose receptor), CD14, CD1a, CD80, CD83, CD86 and MHC II were examined by flow cytometry. The expression of IL-4 mRNA was detected by RT-PCR, while IFN-γ, IL-12 and IL-10 were analyzed by enzyme-linked immunosorbent assay (ELISA) commercial kits.

RESULTS

IVIG of therapeutic dose inhibited the phagocytosis, differentiation and maturation of DCs, whereas physiological dose exhibited an accelerated role in vitro, especially on DCs from neonates, but aroused different effects on cytokine secretion.

DISCUSSION AND CONCLUSION

The different responses are generally due to immature immune system of neonate, which has a limit capacity to maintain immunity homeostasis. Modulation of DCs phagocytosis, differentiation, maturation and cytokine secretion by IVIG is of potential relevance to its dosage and immune status of patients.

Comparative study of subcutaneous versus intravenous IgG replacement therapy in pediatric patients with primary immunodeficiency diseases: a multicenter study in Argentina

PURPOSE

Several studies have shown that subcutaneous immunoglobulin (SCIG) infusions demonstrate similar efficacy to intravenous Ig (IVIG) in preventing infections in patients with primary immunodeficiency diseases (PID), and are safe and well tolerated in this population. This open, prospective/retrospective, multicenter study was designed to compare the effectiveness, safety and tolerability of a 16 % liquid human IgG preparation (Beriglobina P), administered SC, with previous IVIG treatment in PID pediatric patients in Argentina.

METHODS

Fifteen subjects were enrolled in the study, and a total of 13 subjects (aged 6-18 years) completed the 36-week SCIG treatment period. All children had previously received IVIG treatment. The dose of SCIG equaled the previous IVIG dose and subjects received an average weekly dose of 139 mg/kg (range 105-181) during the SCIG period.

RESULTS

Significantly higher serum IgG trough levels were recorded on SCIG treatment at 16, 24, and 36 weeks, when compared with previous IgG trough levels on steady-state IVIG treatment. The annualized infection rate was 1.4 infections/subject/year during the IVIG administration period compared with 0.4 infections/subject/year during the SCIG period. All subjects who completed the study chose to continue administering SCIG at home after the study had ended.

CONCLUSIONS

These data confirm that self-administered SCIG therapy is a well-tolerated and effective alternative to IVIG therapy for children with PID.

Evaluation of correlation between dose and clinical outcomes in subcutaneous immunoglobulin replacement therapy

The importance of serum immunoglobulin (Ig)G concentration in IgG replacement therapy for primary immunodeficiency diseases is established in certain settings. Generally, IgG is infused via the intravenous (IVIG) or subcutaneous (SCIG) route. For IVIG infusion, published data demonstrate that higher IgG doses and trough levels provide patients with improved protection from infection. The same conclusions are not yet accepted for SCIG; data from two recent Phase III studies and a recent post-hoc analysis, however, suggest the same correlation between higher SCIG dose and serum IgG concentration and decreased incidence of infection seen with IVIG. Other measures of clinical efficacy have not been considered similarly. Thus, combined analyses of these and other published SCIG studies were performed; a full comparison of the 13 studies was, however, limited by non-standardized definitions and reporting. Despite these limitations, our analyses indicate that certain clinical outcomes improve at higher SCIG doses and associated higher serum IgG concentrations, and suggest that there might be opportunity to improve patient outcomes via SCIG dose adjustment.

Subcutaneous immunoglobulin therapy: a new option for patients with primary immunodeficiency diseases

Since the 1950s, replacement of immunoglobulin G using human immunoglobulin has been the standard treatment for primary immunodeficiency diseases with defects in antibody production. These patients suffer from recurrent and severe infections, which cause lung damage and shorten their life span. Immunoglobulins given intravenously (IVIG) every 3-4 weeks are effective in preventing serious bacterial infections and improving the quality of life for treated patients. Administration of immunoglobulin subcutaneously (SCIG) is equally effective in preventing infections and has a lower incidence of serious adverse effects compared to IVIG. The tolerability and acceptability of SCIG has been demonstrated in numerous studies showing improvements in quality of life and a preference for subcutaneous immunoglobulin therapy in patients with antibody deficiencies.

Dosing and therapy utilization: a discussion of updates on PI treatment guidelines

Treatment decisions made in clinical practice, based on current guidelines, often conflict with decisions by third-party payors that restrict the ability of patients with primary immunodeficiency disease (PI) to adhere to appropriate treatment. This is seen by many physicians as potentially placing the health of patients at risk. Key treatment decisions challenged by third-party payors and discussed here include dosing, product safety, and routes of administration. Data on safety issues emphasize that IgG products are not generic drugs and each of the products currently licensed by the Food and Drug Administration (FDA) must be regarded as an individual therapy, given the products' different manufacturing processes and stabilizing ingredients. The issue of switching patients to a different product needs careful consideration as evidence shows that infusion-related adverse events in many patients are frequently related to this activity. Decisions regarding the route of therapy should also be individualized to the patient, weighing such factors as side effects, adherence with therapy, and lifestyle.

Subcutaneous immunoglobulin replacement therapy with Hizentra, the first 20% SCIG preparation: a practical approach

To reduce the risk of infection in adults and children with primary immunodeficiencies, replacement therapy with IgG, which can be administered to patients intravenously or subcutaneously, is required. Although intravenous administration of IgG (IVIG) has been the therapy of choice in the US and widely used in Europe for many years, subcutaneous administration of IgG (SCIG) has recently gained considerable acceptance among patients and doctors. SCIG therapy achieves high and stable serum IgG levels, is well tolerated, and can be self-administered. Hizentra (IgPro20; CSL Behring, Berne, Switzerland) is the first, ready-to-use 20% liquid preparation of human IgG specifically formulated for subcutaneous infusions. The high concentration (20%) might allow shorter infusion times due to smaller infusion volumes, with potential improvement in the convenience of SCIG therapy. Hizentra is well tolerated and has been shown to protect adult and pediatric primary immunodeficiency patients against serious bacterial infections. In addition, it is easy to handle and can be stored at a temperature up to 25°C. In summary, Hizentra is an advance in the field of immunoglobulin replacement therapy, which might offer benefits for home therapy patients.

Efficacy and safety of home-based subcutaneous immunoglobulin replacement therapy in paediatric patients with primary immunodeficiencies

Subcutaneous immunoglobulin infusions are effective, safe and well tolerated in the treatment of primary immunodeficiencies, but only limited data on the treatment of children are available. We investigated the efficacy, safety and pharmacokinetics of home therapy with a 16% liquid human immunoglobulin G preparation (Vivaglobin®) when administered subcutaneously in children with primary immunodeficiencies. Data were analysed from 22 children (2-<12 years) who participated in two prospective, open-label studies (one in Europe/Brazil, one in North America). All children had previously received intravenous immunoglobulins. They started weekly subcutaneous immunoglobulin infusions with an approximately 3-month wash-in/wash-out period, followed by a 6-month (Europe/Brazil) or 12-month (North America) efficacy evaluation period. In Europe/Brazil, subcutaneous doses generally equalled the previous weekly equivalent intravenous doses. In North America, subcutaneous doses during the efficacy evaluation period were 126% (median) of the previous weekly equivalent intravenous doses. Efficacy end-points in both studies included the occurrence of serious bacterial infections and any infections, and serum immunoglobulin G trough levels. Median serum immunoglobulin G trough levels exceeded those during previous intravenous therapy by 13% (North America) and 16% (Europe/Brazil). During the efficacy evaluation period of both studies, none of the children had a serious bacterial infection; the mean overall infection rate/patient year was 4·7 in Europe/Brazil and 5·6 in North America, concurring with previous reports in adults. The adverse event profile was comparable to previous reports in adults. Both studies confirmed the efficacy and safety of subcutaneous immunoglobulin therapy with Vivaglobin in children with primary immunodeficiencies.

Pharmacokinetics and safety of subcutaneous immune globulin (human), 10% caprylate/chromatography purified in patients with primary immunodeficiency disease

Subcutaneous administration of intravenous immunoglobulin G (IgG) preparations provides an additional level of patient convenience and more options for patients with poor venous access or a history of intravenous IgG reactions. An open-label, pharmacokinetic trial (n = 32) determined the non-inferiority of the subcutaneous versus intravenous route of 10% caprylate/chromatography purified human immune globulin intravenous (IGIV-C; Gamunex®) administration by comparing the steady-state area under the concentration-versus-time curve (AUC) of total plasma IgG in patients with primary immunodeficiency disease. Patients on stable IGIV-C received two intravenous infusions (administered 3 or 4 weeks apart). Seven to 10 days after the second intravenous infusion, all patients switched to a weekly infusion of subcutaneous IGIV-C, with the dose equal to 137% of the previous weekly equivalent intravenous dose, for up to 24 weeks. Samples for pharmacokinetic analysis were collected during steady state for intravenous and subcutaneous IGIV-C treatments. The AUC(0-) τ geometric least-squares mean ratio was 0·89 (90% confidence interval, 0·86-0·92) and met the criteria for non-inferiority. The overall mean steady-state trough concentration of plasma total IgG with subcutaneous IGIV-C was 11·4 mg/ml, 18·8% higher than intravenous IGIV-C (9·6 mg/ml). Subcutaneous IGIV-C was safe and well tolerated. Subcutaneous IGIV-C infusion-site reactions were generally mild/moderate and the incidence decreased over time. No serious bacterial infections were reported. Weekly subcutaneous IGIV-C infusion using 137% of the weekly equivalent intravenous immunoglobulin dose provides an AUC comparable to intravenous administration, thus allowing patients to maintain the same IgG preparation/formulation if switching between intravenous and subcutaneous infusions.

[Subcutaneous immunoglobulin substitution and therapy]

Patients with combined primary immunodeficiency or B-cell deficiency with low serum concentration of immunoglobulin G can be efficiently treated with immunoglobulin G concentrates. From the 1950s IgG was used intramuscularly, and from the 1980s intravenous immunoglobulin (IVIG) replacement has become widely available for replacement therapy. Among the potential side effects of IVIG (including anaphylaxis), further disadvantages of IVIG are hospitalization during treatment and varying concentrations of IgG. Over the past ten years, subcutaneous IgG (SCIG) preparations have become reasonable alternatives to IVIG. SCIG given weekly assures a more balanced serum IgG level, side affects are mostly local and temporary; systemic, severe adverse events have not been observed. In addition, SCIG can be used for home treatment of patients which improves their quality of life remarkably.

Home-based subcutaneous immunoglobulin G replacement therapy under real-life conditions in children and adults with antibody deficiency

Background

Subcutaneous immunoglobulin (SCIG) therapy is an alternative to intravenous immunoglobulin (IVIG) therapy.

Methods

We evaluated the efficacy and safety of the SCIG Vivaglobin^® (formerly known as Beriglobin^® SC) under real-life conditions in a post-marketing observational study in 82 patients with primary or secondary antibody deficiencies. Health-related quality of life (HRQoL) was evaluated in a subset of 30 patients previously treated with IVIG (including 11 children < 14 years) using the Short Form 36 (SF-36) for patients ≥ 14 years of age (adults) and the Child Health Questionnaire - Parental Form 50 (CHQ-PF50) for children < 14 years of age. Treatment preferences were assessed in adults.

Results

The mean serum immunoglobulin G (IgG) trough level during SCIG treatment (7.5 g/L) was higher than during previous IVIG treatment (6.6 g/L; p < 0.01). The investigators assessed the efficacy of SCIG therapy as "excellent" in 89% of patients. No systemic adverse drug reactions were observed. Improvements by ≥ 5 points were observed in 5 of 8 SF36 subscales and in 6 of 12 CHQ-PF50 subscales. Statistically significant improvements (p ≤ 0.05) were observed for the SF-36 subscales of bodily pain, general health perceptions, and vitality (adults), and for the CHQ-PF50 subscales of general health perceptions, parental impact - time, parental impact - emotional, and family activities (children). Patients preferred SCIG over IVIG therapy (92%) and home therapy over therapy at the clinic/physician (83%).

Conclusion

This study confirms that therapy with Vivaglobin^® at home is effective, safe, well tolerated, and improves quality of life in patients with antibody deficiency.

Economic evaluation of immunoglobulin replacement in patients with primary antibody deficiencies

Lifelong immunoglobulin replacement is the standard, expensive therapy for severe primary antibody deficiencies. This treatment can be administrated either by intravenous immunoglobulin (IVIG) or subcutaneous infusions (SCIG) and delivered at home or in an out-patient setting. This study aims to determine whether SCIG is cost-effective compared with IVIG from a French social insurance perspective. Because both methods of administration provide similar efficacies, a cost-minimization analysis was performed. First, costs were calculated through a simulation testing different hypothesis on costs drivers. Secondly, costs were estimated on the basis of field data collected by a questionnaire completed by a population of patients suffering from agammaglobulinaemia and hyper-immunoglobulin (Ig)M syndrome. Patients' satisfaction was also documented. Results of the simulation showed that direct medical costs ranged from 19 484 euro for home-based IVIG to 25 583 euro for hospital-based IVIG, with home-based SCIG in between at 24 952 euro per year. Estimations made from field data were found to be different, with significantly higher costs for IVIG. This result was explained mainly by a higher immunoglobulin mean dose prescribed for IVIG. While the theoretical model showed very little difference between SCIG and hospital-based IVIG costs, SCIG appears to be 25% less expensive with field data because of lower doses used in SCIG patients. The reality of the dose difference between both routes of administration needs to be confirmed by further and more specific studies.

Pathogenesis, diagnosis, and management of primary antibody deficiencies and infections

Primary antibody deficiencies are the most common primary immunodeficiency diseases. They are a heterogeneous group of disorders with various degrees of dysfunctional antibody production resulting from a disruption of B-cell differentiation at different stages. While there has been tremendous recent progress in the understanding of some of these disorders, the etiology remains unknown for the majority of patients. As there is a large spectrum of underlying defects, the age at presentation varies widely, and the clinical manifestations range from an almost complete absence of B cells and serum immunoglobulins to selectively impaired antibody responses to specific antigens with normal total serum immunoglobulin concentrations. However, all of these disorders share an increased susceptibility to infections, affecting predominantly the respiratory tract. A delay of appropriate treatment for some diseases can result in serious complications related to infections, while timely diagnosis and adequate therapy can significantly decrease morbidity and increase life expectancy and quality of life.

Subcutaneous immunoglobulin therapy in pediatric primary antibody deficiency

Subcutaneous immunoglobulin (SCIG) therapy is recognized as a standard treatment for primary antibody deficiency. SCIG is efficacious for the prevention of infections and is associated with a lower risk of systemic side effects, improved quality of life for patients and families and is preferred by children when compared with intravenous immunoglobulin replacement. For pediatric patients, SCIG is an ideal treatment modality that affords children and families more freedom and less disruption of important childhood activities. This article reviews the characteristics of SCIG to provide the pediatric practitioner with an understanding of the experiences their patients receiveing SCIG may encounter.

Immunoglobulin replacement therapy in children

The benefit of immunoglobulin (IG) replacement in primary antibody deficiencies is unquestionable. Many of these congenital disorders present early in life and this therapy is often first implemented in the young. This article focuses on the indications of IG replacement in children, with an emphasis on the specific diagnostic problems encountered in this population. Also presented is an overview of the practical aspects of IG administration in the pediatric setting, including the recognition and management of adverse reactions. Finally, the advent of subcutaneous IG, a therapeutic IG modality with the potential to have a great impact on the quality of life of children with antibody deficiencies and their families, is discussed.

Subcutaneous immunoglobulin replacement therapy for primary antibody deficiency: advancements into the 21st century

OBJECTIVES

To provide a review of the world literature and discuss the clinical role of subcutaneous immunoglobulin (SCIG) therapy for primary antibody deficiency.

DATA SOURCES

English-language publications on SCIG therapy were identified through MEDLINE and through the reference list of the initially identified publications.

STUDY SELECTION

Articles pertaining to SCIG for the treatment of immunodeficiency, particularly primary antibody deficiency, were selected.

RESULTS

SCIG therapy has been shown to be effective and safe for the treatment of primary immunodeficiency. The risk of systemic reactions during infusion is generally reported to be less than 1%. Many patients prefer SCIG over conventional intravenous immunoglobulin therapy because of increased convenience and independence associated with SCIG therapy. Publications show SCIG therapy to be advantageous in selected patient populations, such as children, pregnant women, and patients with poor intravenous access.

CONCLUSION

SCIG therapy has been widely used in some European countries for a number of years, but a Food and Drug Administration-approved product was only recently introduced into the United States in 2006. SCIG therapy offers unique advantages that are applicable to many patients receiving immunoglobulin therapy for primary immunodeficiency.