Human normal immunoglobulin in the treatment of primary immunodeficiency diseases

Antigen-Antibody Complexes

In vertebrates, immunoglobulins (Igs), commonly known as antibodies, play an integral role in the armamentarium of immune defense against various pathogens. After an antigenic challenge, antibodies are secreted by differentiated B cells called plasma cells. Antibodies have two predominant roles that involve specific binding to antigens to launch an immune response, along with activation of other components of the immune system to fight pathogens. The ability of immunoglobulins to fight against innumerable and diverse pathogens lies in their intrinsic ability to discriminate between different antigens. Due to this specificity and high affinity for their antigens, antibodies have been a valuable and indispensable tool in research, diagnostics and therapy. Although seemingly a simple maneuver, the association between an antibody and its antigen, to make an antigen-antibody complex, is comprised of myriads of non-covalent interactions. Amino acid residues on the antigen binding site, the epitope, and on the antibody binding site, the paratope, intimately contribute to the energetics needed for the antigen-antibody complex stability. Structural biology methods to study antigen-antibody complexes are extremely valuable tools to visualize antigen-antibody interactions in detail; this helps to elucidate the basis of molecular recognition between an antibody and its specific antigen. The main scope of this chapter is to discuss the structure and function of different classes of antibodies and the various aspects of antigen-antibody interactions including antigen-antibody interfaces-with a special focus on paratopes, complementarity determining regions (CDRs) and other non-CDR residues important for antigen binding and recognition. Herein, we also discuss methods used to study antigen-antibody complexes, antigen recognition by antibodies, types of antigens in complexes, and how antigen-antibody complexes play a role in modern day medicine and human health. Understanding the molecular basis of antigen binding and recognition by antibodies helps to facilitate the production of better and more potent antibodies for immunotherapy, vaccines and various other applications.

Quality of Life Differences for Primary Immunodeficiency Patients on Home SCIG versus IVIG

Background

Patients with primary immunodeficiency disease (PIDD) and antibody deficiency require lifelong immunoglobulin replacement therapy. While both subcutaneous immunoglobulin (SCIG) and intravenous immunoglobulin (IVIG) replacement therapy are effective in preventing infection, patients with PIDD still experience worse health-related quality of life (hrQOL) outcomes.

Objective

Assess differences in hrQOL for PIDD patients receiving home SCIG versus IVIG.

Methods

SF-36 surveys were administered by a specialty pharmacy to 630 PIDD patients receiving home SCIG and IVIG at baseline and then every 3 months between 2014 and 2016. Results were analyzed using two-sample t tests and linear mixed effects model. Analysis was repeated for different age categories and trended over time.

Results

Patients receiving SCIG reported statistically significant higher energy fatigue scores (+ 9 points, p < 0.001) but lower perceived role limitations due to physical health scores (− 14 points, p < 0.001). These differences were only observed in patients > 36 years of age. There were no differences in the composite SF-36 score for patients receiving SCIG versus IVIG (+ 1, p = 0.66). Immunoglobulin-naïve patients all improved their hrQOL, but a larger improvement was seen in those initiating SCIG versus IVIG.

Conclusion

Patients with PIDD on home IVIG versus SCIG have similar composite hrQOL scores as measured by the SF-36. In the adult population, initiating immunoglobulin replacement with SCIG may result in more hrQOL improvement compared with IVIG, although personal preferences should also be considered.

Clinical Implications

Patients with PIDD on home IVIG versus SCIG have similar composite health-related quality of life scores as measured by the SF-36.

Capsule Summary

Patients with primary immune-deficiency on home IVIG versus SCIG have similar composite health-related quality of life scores as measured by the SF-36. Personal preferences are important in deciding whether to treat with IVIG or SCIG.

Electronic supplementary material

The online version of this article (10.1007/s10875-019-00705-5) contains supplementary material, which is available to authorized users.

What Is the Burden of Immunoglobulin Replacement Therapy in Adult Patients With Primary Immunodeficiencies? A Systematic Review

Background

Primary immunodeficiency disorders (PIDs) are a group of heterogeneous rare disorders, whereby the immune system is missing or not functioning adequately. For patients requiring treatment, the most common option is immunoglobulin replacement therapy (Ig). Treatment of PIDs is simultaneously associated with both improvements in health-related quality of life (HRQoL) and increased treatment burden.

Objectives

This review sought to review studies investigating the burden of Ig treatment, synthesize evidence in relation to administration routes (subcutaneous or intravenous) and instruments used, as well as make recommendations for clinical and research applications in this area for patients aged 16 years and older.

Methods

We searched Medline, EMBASE, and The Cochrane Library. Sifting of titles was performed by two reviewers, and the assessment of full-text articles by three. From a database which contained 3,770 unique results, 67 full texts were reviewed. Eventually, 17 studies were found to meet the inclusion criteria, and included in this review. Due to data heterogeneity, a narrative, descriptive synthesis of the evidence was undertaken.

Results

Most studies were carried out in the USA/North America, used a prospective observational design and involved patients with common variable immune deficiency. Four studies measured the burden of receiving IVIg therapy and 13 measured SCIg therapy. A wide range of measures, primarily designed to measure aspects of treatment satisfaction (e.g., life quality index or a slightly modified version) and HRQoL (e.g., The Short Form-36) had been used.

Conclusion

Lack of a parallel control group in most studies meant that changes in outcomes could be due to factors other than changes in the treatment regimen. However, overall, PID patients appeared to report little Ig treatment burden and were satisfied with either modality. However, patient preference appeared to be the delivery of the Ig treatment in the patient's home and SCIg was preferred after switching from IVIg therapy. Individual differences appeared to affect treatment preference and therefore understanding the decision support needs of PID patients facing IG treatment choices would be valuable. Using a questionnaire specifically designed to measure the burden of Ig treatment from the patient's perspective is recommended in future research.

Pharmacokinetics of a novel human intravenous immunoglobulin 10% in patients with primary immunodeficiency diseases: Analysis of a phase III, multicentre, prospective, open-label study

Intravenous immunoglobulin (IVIG) therapy is commonly used to treat patients with primary antibody deficiency. This prospective, open-label, non-randomised, multicentre, phase III trial investigated the pharmacokinetics of a new 10% liquid IVIG product (panzyga®; Octapharma) in 51 patients aged 2-75 years with common variable immunodeficiency (n = 43) or X-linked agammaglobulinaemia (n = 8). Patients were treated with IVIG 10% every 3 (n = 21) or 4 weeks (n = 30) at a dose of 200-800 mg/kg for 12 months. Total immunoglobulin G (IgG) and subclass concentrations approximately doubled from pre- to 15 min post-infusion. The maximum concentration of total IgG (mean ± SD) was 21.82 ± 5.83 g/L in patients treated 3-weekly and 17.42 ± 3.34 g/L in patients treated 4-weekly. Median trough IgG concentrations were nearly constant over the course of the study, remaining between 11.0 and 12.2 g/L for patients on the 3-week schedule and between 8.10 and 8.65 g/L for patients on the 4-week schedule. The median terminal half-life of total IgG was 36.1 (range 18.5-65.9) days, with generally similar values for the IgG subclasses (26.7-38.0 days). Median half-lives for specific antibodies ranged between 21.3 and 51.2 days for anti-cytomegalovirus, anti-Haemophilus influenzae, anti-measles, anti-tetanus toxoid, anti-varicella zoster virus antibodies, and anti-Streptococcus pneumoniae subtype antibodies. Overall, IVIG 10% demonstrated pharmacokinetic properties similar to those of other commercial IVIG 10% preparations and 3- or 4-weekly administration achieved sufficient concentrations of IgG, IgG subclasses, and specific antibodies, exceeding the recommended level needed to effectively prevent serious bacterial infections.

Rapid infusions of human normal immunoglobulin 50g/l are safe and well tolerated in immunodeficiencies and immune thrombocytopenia

Intravenous immunoglobulin (IVIg) is accepted as an effective and well-tolerated treatment for primary and secondary immunodeficiencies (ID) and immune thrombocytopenia (ITP). Adverse reactions of IVIg are usually mild, comprising transient flu-like symptoms, change in blood pressure and tachycardia. However IVIg therapy can be burdensome for both patients and healthcare facilities, since the infusion may take up to 4h to administer. The objective of our multicentre, prospective, open-label phase III trial was to evaluate the tolerability and safety of human normal immunoglobulin 50g/l (Ig VENA) at high intravenous infusion rates in adult patients with ID and ITP who had previously tolerated IVIg treatment, by progressively increasing infusion rate up to 8ml/kg/hr. 39 ID patients received three infusions, 5 ITP patients received up to a maximum of 5 infusions for a maximum of 5days. Overall 55 adverse events were reported in 18 patients, and all were mild and self-limiting. Two serious adverse events occurred in ID patients and 1 in an ITP patient; none was fatal or treatment-related. No clinically significant changes or abnormalities were observed in vital signs, laboratory results and HRQoL. In summary, in this study, more rapid IVIg infusions were well tolerated by ID and ITP patients, while maintaining their quality of life, helping to minimise the time spent in outpatient hospital visiting to potentially optimise adherence to treatment.

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.

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.

Primary immunodeficiency diseases: a primer for PCPs

Primary care providers (PCPs) play a key role in identifying patients with primary immunodeficiency diseases (PIDDs). This diagnosis has implications for PCPs, as patients continue to require primary care and management after a PIDD diagnosis has been made. This review presents essential information for PCPs regarding PIDDs.

Improving current immunoglobulin therapy for patients with primary immunodeficiency: quality of life and views on treatment

BACKGROUND

Subcutaneous or intravenous immunoglobulin replacement is the mainstay of treatment for most patients with primary immunodeficiency disease (PID). The purpose of this study was to gain an understanding of how existing PID therapies affect patient lives and to identify desired improvements to immunoglobulin treatments.

METHODS

An online questionnaire was made available through the International Patient Organisation for Primary Immunodeficiencies to patients with PID and their caregivers regarding current treatment satisfaction, living with PID, and patient preferences using a conjoint approach. Health-related quality of life was canvassed via questionnaires using the Short Form 12 Health Survey and EuroQoL 5 Dimensions.

RESULTS

A total of 300 responded to the survey (72% patients with PID and 28% caregivers) from across 21 countries, mostly the UK, Sweden, Canada, France, Germany, and Spain. Fifty-three percent and 45% of patients received intravenous and subcutaneous therapy, respectively. Most respondents (76%) were satisfied with their current treatment, reflecting the benefits that immunoglobulin therapy provides for patient health and well-being. However, patients remained below the physical and mental well-being norms for health-related quality of life as determined by the questionnaire. All respondents expressed a desire for 4-weekly infusions, the ability to administer these at home, self-administration, shorter duration of administration, and fewer needle sticks.

CONCLUSION

The results of this survey highlight the importance of providing access to different treatment options and modes of administration to ensure individual patient needs are best met.

Analysis of the landscape of biologically-derived pharmaceuticals in Europe: dominant production systems, molecule types on the rise and approval trends

A thorough sort of the human drugs approved by the European Medicines Agency (EMA) between its establishment in 1995 until June 2012 is presented herein with a focus on biologically-derived pharmaceuticals. Over 200 (33%) of the 640 approved therapeutic drugs are derived from natural sources, produced via recombinant DNA technology, or generated through virus propagation. A breakdown based on production method, type of molecule and therapeutic category is presented. Current EMA approvals demonstrate that mammalian cells are the only choice for glycoprotein drugs, with Chinese hamster ovary cells being the dominant hosts for their production. On the other hand, bacterial cells and specifically Escherichia coli are the dominant hosts for protein-based drugs, followed by the yeast Saccharomyces cerevisiae. The latter is the dominant host for recombinant vaccine production, although egg-based production is still the main platform of vaccine provision. Our findings suggest that the majority of biologically-derived drugs are prescribed for cancer and related conditions, as well as the treatment of diabetes. The approval rate for biologically-derived drugs shows a strong upward trend for monoclonal antibodies and fusion proteins since 2009, while hormones, antibodies and growth factors remain the most populous categories. Despite a clear pathway for the approval of biosimilars set by the EMA and their potential to drive sales growth, we have only found approved biosimilars for three molecules. In 2012 there appears to be a slow-down in approvals, which coincides with a reported decline in the growth rate of biologics sales.