Safety and efficacy of Privigen, a novel 10% liquid immunoglobulin preparation for intravenous use, in patients with primary immunodeficiencies

fSCIG 10% in pediatric primary immunodeficiency diseases: a European post-authorization safety study

BACKGROUND

The safety, tolerability, and immunogenicity of hyaluronidase-facilitated subcutaneous immunoglobulin (fSCIG) 10% (dual-vial unit of human immunoglobulin 10% and recombinant human hyaluronidase [rHuPH20]) were assessed in children with primary immunodeficiency diseases (PIDs).

METHODS

This phase 4, post-authorization, prospective, interventional, multicenter study (NCT03116347) conducted in the European Economic Area, enrolled patients aged 2 to < 18 years with a documented PID diagnosis who had received immunoglobulin therapy for ≥ 3 months before enrollment. New fSCIG 10% starters underwent fSCIG 10% dose ramp-up for ≤ 6 weeks (epoch 1) before receiving fSCIG 10% for ≤ 3 years (epoch 2); patients pretreated with fSCIG 10% entered epoch 2 directly. The primary outcome was the number and rate (per infusion) of all noninfectious treatment-related serious and severe adverse events (AEs).

RESULTS

In total, 42 patients were enrolled and dosed (median [range] age: 11.5 [3-17] years; 81% male; 23 new starters; 19 pretreated). Overall, 49 related noninfectious, treatment-emergent AEs (TEAEs) were reported in 15 patients; most were mild in severity (87.8%). No treatment-related serious TEAEs were reported. Two TEAEs (infusion site pain and emotional distress) were reported as severe and treatment-related in a single new fSCIG 10% starter. The rate of local TEAEs was lower in pretreated patients (0.1 event/patient-year) versus new starters (1.3 events/patient-year). No patients tested positive for binding anti-rHuPH20 antibodies (titer of ≥ 1:160).

CONCLUSIONS

No safety signals were identified, and the incidence of local AEs declined over the duration of fSCIG 10% treatment. This study supports fSCIG 10% long-term safety in children with PIDs. TRIAL REGISTRATION NUMBER (CLINICALTRIALS.GOV): NCT03116347.

Initiating immunoglobulin replacement therapy helps reduce severe infections and shifts healthcare resource utilization to outpatient services among US patients with inborn errors of immunity

AIMS

Patients with inborn errors of immunity (IEI) are predisposed to severe recurrent/chronic infections, and often require hospitalization, resulting in substantial burden to patients/healthcare systems. While immunoglobulin replacement therapies (IgRTs) are the standard first-line treatment for most forms of IEI, limited real-world data exist regarding clinical characteristics and treatment costs for patients with IEI initiating such treatment. This retrospective analysis examined infection and treatment characteristics in US patients with IEI initiating IgRT with immune globulin infusion (human), 10% (IG10%). Healthcare resource utilization (HCRU) and associated costs before and after treatment initiation were compared. Additionally, the impact of COVID-19 on infection diagnoses was evaluated.

METHODS

Patients with IEI initiating IG10% between July 2012 and August 2019 were selected from Merative MarketScan Databases using diagnosis/prescription codes. Patients were followed 6 months before and after first IG10% claim date. Demographic and clinical characteristics were described. Treatment characteristics and HCRU before and after IG10% initiation were compared. Infection diagnoses during 2020 and 2019 (March-December) were compared.

RESULTS

The study included 1,497 patients with IEI diagnoses (mean age = 43.4 years) initiating IG10%, with frequently reported comorbidities like asthma (32.1%). Following IG10% initiation, fewer severe infection diagnoses (11.6% vs 19.9%), fewer infection-related inpatient (10.8% vs 19.5%) and outpatient services (71.6% vs 79.9%), and lower infection-related total healthcare costs ($7,849 vs $13,995; p < 0.001)-driven by lower inpatient costs ($2,746 vs $9,900)-were observed than before. Fewer patients had infection diagnoses during COVID-19 (22.8%) than the prior year (31.2%).

CONCLUSION

Patients with IEI are susceptible to severe infections leading to high disease burden and treatment costs. Following IG10% initiation, we observed fewer infections, lower infection-related treatment costs, and shift in care (inpatient to outpatient) leading to significant cost savings. Among patients with IEI, 27% fewer infection diagnoses were observed during the early COVID-19 lockdown period than the prior year.

Safety and Efficacy of Hizentra® Following Pediatric Hematopoietic Cell Transplant for Treatment of Primary Immunodeficiencies

Primary immunodeficiency disease (PIDD) comprises a group of disorders of immune function. Some of the most severe PIDD can be treated with hematopoietic cell transplant (HCT). Hizentra® is a 20% liquid IgG product approved for subcutaneous administration in adults and children greater than 2 years of age with PIDD-associated antibody deficiency. Limited information is available on the use of Hizentra® in children following HCT for PIDD. A multicenter retrospective chart review demonstrated 37 infants and children (median age 70.1 [range 12.0 to 176.4] months) with PIDD treated by HCT who received Hizentra® infusions over a median duration of 31 (range 4-96) months post-transplant. The most common indication for HCT was IL2RG SCID (n = 16). Thirty-two patients switched from IVIG to SCIG administration, due to one or more of the following reasons: patient/caregiver (n = 17) or physician (n = 12) preference, discontinuation of central venous catheter (n = 16), desire for home infusion (n = 12), improved IgG serum levels following lower levels on IVIG (n = 10), and loss of venous access (n = 8). Serious bacterial infections occurred at a rate of 0.041 per patient-year while on therapy. Weight percentile increased by a mean of 16% during the observation period, with females demonstrating the largest gains. Mild local reactions were observed in 24%; 76% had no local reactions. One serious adverse event (death from sepsis) was reported. Hizentra® was discontinued in 15 (41%) patients, most commonly due to recovery of B cell function (n = 11). These data demonstrate that Hizentra® is a safe and effective option in children who have received HCT for PIDD.

Exact sample size determination for a single Poisson random sample

Classical power analysis for sample size determination is typically performed in clinical trials. A "hybrid" classical Bayesian or a "fully Bayesian" approach can be alternatively used in order to add flexibility to the design assumptions needed at the planning stage of the study and to explicitly incorporate prior information in the procedure. In this paper, we exploit and compare these approaches to obtain the optimal sample size of a single-arm trial based on Poisson data. We adopt exact methods to establish the rejection of the null hypothesis within a frequentist or a Bayesian perspective and suggest the use of a conservative criterion for sample size determination that accounts for the not strictly monotonic behavior of the power function in the presence of discrete data. A Shiny web app in R has been developed to provide a user-friendly interface to easily compute the optimal sample size according to the proposed criteria and to assure the reproducibility of the results.

Systemic IgG exposure and safety in patients with primary immunodeficiency: a randomized crossover study comparing a novel investigational wearable infusor versus the Crono pump

Aim: A novel, Investigational Wearable Infusor (IWI) was evaluated in a randomized, controlled, crossover, open-label study to determine if its delivery of subcutaneous immunoglobulin (IgPro20) achieved a comparable area under the concentration-time curve (AUC) for immunoglobulin G (IgG) versus the Crono S-PID-50 infusion pump (CP). EudraCT: 2016-003798-16. Materials & methods: Patients with primary immunodeficiency (PID) were randomized to receive IgPro20 in Sequence 1 (CP/IWI) or 2 (IWI/CP). The primary end point was AUC for IgG during the final week of each 4-week period. Results: 23 patients were enrolled. Evaluation of area under the concentration-time curve from time 0 (pre-infusion) to 7 days after infusion (AUC_0-7 days) (IWI: 1806 h*g/l; CP: 1829 h*g/l) and geometric mean ratio indicated comparable AUCs for IgG for both devices. Conclusion: Similar IgG exposure, indicated by AUC values, can be achieved with IgPro20 using the IWI or CP in PID.

Infection rates and tolerability of three different immunoglobulin administration modalities in patients with primary immunodeficiency diseases

Aim: This post hoc analysis evaluated the efficacy and overall tolerability of immunoglobulin (Ig) treatment modalities (intravenous Ig [iv.Ig], subcutaneous Ig [sc.Ig] and facilitated sc.Ig [fsc.Ig]). Materials & methods: A total of 30 participants with primary immunodeficiency diseases aged ≥2 years sequentially received iv.Ig, sc.Ig and fsc.Ig during consecutive clinical studies. Results: For iv.Ig, sc.Ig and fsc.Ig, rates of validated acute serious bacterial infections/participant-year (0, 0.09 and 0.04, respectively) and all infections/participant year (4.17, 3.68 and 2.42, respectively) were similarly low; rates of systemic and local causally related adverse events/participant-year were 5.60, 1.93 and 0.88, respectively and 0.13, 0.92 and 1.57, respectively. Conclusion: fsc.Ig provided similar efficacy to iv.Ig and sc.Ig. Clinical Trial registration: NCT00546871, NCT00814320, NCT01175213 (ClinicalTrials.gov).

Functionality of the human antibody response to Candida albicans

Candida albicans is a common commensal on human mucosal surfaces, but can become pathogenic, e.g. if the host is immunocompromised. While neutrophils, macrophages and T cells are regarded as major players in the defense against pathogenic C. albicans, the role of B cells and the protective function of their antibodies are less well characterized. In this study, we show that human serum antibodies are able to enhance the association of human THP-1 monocyte-like cells with C. albicans cells. Human serum antibodies are also capable of inhibiting the adherence and damage dealt to epithelial cells. Furthermore, human serum antibodies impair C. albicans invasion of human oral epithelial cells by blocking induced endocytosis and consequently host cell damage. While aspartic proteases secreted by C. albicans are able to cleave human IgG, this process does not appear to affect the protective function of human antibodies. Thus, humans are equipped with a robust antibody response to C. albicans, which can enhance antifungal activities and prevent fungal-mediated epithelial damage.

A systematic review of population pharmacokinetic analyses of polyclonal immunoglobulin G therapy

BACKGROUND

Population pharmacokinetics (popPK) using the nonlinear mixed-effect (NLME) modeling approach is an essential tool for guiding dose individualization. Several popPK analyses using the NLME have been conducted to characterize the pharmacokinetics of immunoglobulin G (IgG).

OBJECTIVE

To summarize the current information on popPK of polyclonal IgG therapy.

METHOD

A systematic search was conducted in the PubMed and Web of Science databases from inception to December 2020. Additional relevant studies were also included by reviewing the reference list of the reviewed articles. All popPK studies that employed the NLME modeling approach were included and data were synthesized descriptively.

RESULTS

This review included seven studies. Most of the popPK models were developed in patients with primary immunodeficiency (PID). IgG pharmacokinetics was described as a two-compartment model in five studies, while it was described as a one-compartment model in two other studies. Among all tested covariates, weight was consistently identified as a significant predictor for clearance (CL) of IgG. Whereas, weight and disease type were found to be significant predictors for the volume of distribution in central compartment (Vc). In a typical 70 kg adult, the median estimated values of Vc and CL were 4.04 L and 0.144 L/day, respectively. The between subject variability of Vc was considered large. Only two studies evaluated their models using external data.

CONCLUSIONS

Seven popPK studies of IgG were found and discussed, with only weight being a significant covariate across all studies. Future studies linking pharmacokinetics with pharmacodynamics in PID and other patient populations are required.

Efficacy, Safety and Tolerability of a New 10% Intravenous Immunoglobulin for the Treatment of Primary Immunodeficiencies

We report here the results of a phase 3 study to assess the efficacy, safety, and tolerability of GC5107, a new 10% liquid intravenous immunoglobulin (IVIG) in preventing serious bacterial infections in patients with primary immunodeficiency (ClinicalTrials.gov: NCT02783482). Over a 12-month study period, 49 patients aged 3 to 70 years with a confirmed diagnosis of primary immunodeficiency received GC5107 at doses ranging from 319 to 881 mg/kg body weight every 21 or 28 days, according to their previous IVIG maintenance therapy. A total of 667 infusions of GC5107 were administered comprising a total of 45.86 patient-years of treatment. A single acute serious bacterial infection occurred during the study, resulting in an incidence of 0.02 events per patient-year (upper 99% one-sided confidence interval limit: 0.21), meeting the prespecified primary efficacy endpoint. The mean incidence of infections other than acute serious bacterial infections was 2.9 infections per patient-year. Efficacy was also demonstrated by the low mean annualized rate of hospitalizations due to infection (0.1 day) and the mean annualized duration of hospitalizations (0.1 day). The mean rate of intravenous and oral antibiotic use was 0.1 day and 13.2 days, respectively. There was a mean of 7.1 days of missed work, school, or daycare days. The proportion of infusions with temporally associated adverse events (TAAEs) occurring during or within 72 hours after GC5107 infusion was 0.24 (upper 95% one-sided confidence interval limit: 0.31), meeting the pre-specified primary safety endpoint. Overall, 149 of 667 infusions (22%) were associated with TAAEs. The most common TAAE was headache, reported by 49% of patients. More than 98% (731/743) of all adverse events that occurred throughout the 12-month study period were mild or moderate. More than 98% of infusions were completed without discontinuation, interruption or rate reduction. There were no treatment-emergent serious adverse events related to GC5107 or study discontinuations due to an adverse event. Overall, pharmacokinetic parameters for GC5107 were within the range of those reported in studies of other marketed IVIG products. Results of the present study demonstrate that GC5107 is an effective, safe and well-tolerated treatment for patients with primary immunodeficiency.

Population pharmacokinetic modelling of intravenous immunoglobulin in patients with predominantly antibody deficiencies

AIMS

There is considerable interpatient variability in the pharmacokinetics (PK) of intravenous immunoglobulin G (IVIG), causing difficulty in optimizing individual dosage regimen. This study aims to estimate the population PK parameters of IVIG and to investigate the impact of genetic polymorphism of the FcRn gene and clinical variability on the PK of IVIG in patients with predominantly antibody deficiencies.

METHODS

Patients were recruited from four hospitals. Clinical data were recorded and blood samples were taken for PK and genetic studies. Population PK parameters were estimated by nonlinear mixed-effects modelling in Monolix®. Models were evaluated using the difference in objective function value, goodness-of-fit plots, visual predictive check and bootstrap analysis. Monte Carlo simulation was conducted to evaluate different dosing regimens for IVIG.

RESULTS

A total of 30 blood samples were analysed from 10 patients. The immunoglobulin G concentration data were best described by a one-compartment model with linear elimination. The final model included both volume of distribution (Vd) and clearance (CL) based on patient's individual weight. Goodness-of-fit plots indicated that the model fit the data adequately, with minor model mis-specification. Genetic polymorphism of the FcRn gene and the presence of bronchiectasis did not affect the PK of IVIG. Simulation showed that 3-4-weekly dosing intervals were sufficient to maintain IgG levels of 5 g L-1 , with more frequent intervals needed to achieve higher trough levels.

CONCLUSIONS

Body weight significantly affects the PK parameters of IVIG. Genetic and other clinical factors investigated did not affect the disposition of IVIG.

Safety and tolerability of IgPro10 in Japanese primary immunodeficiency patients: a registrational study

Studies investigating the safety of IgPro10 (Privigen^®, CSL Behring, King of Prussia, PA, USA) in Japanese patients with primary immunodeficiency (PID) are lacking. This study evaluated safety and tolerability of IgPro10 in Japanese patients with PID. In this prospective, open-label, single-arm, registrational study for Japan, IgPro10 was administered intravenously at pre-study doses of 138-556 mg/kg body weight per 3-/4-weekly dosing cycle for up to 4 months. Frequency and intensity of adverse events (AEs), their relationship to IgPro10 and AE rate per infusion (AERI) were evaluated. Of 11 enrolled patients, 10 completed the study. The median (range) total duration of exposure was 16.14 (4.1-16.3) weeks. Eight patients reported 19 AEs, none severe (based on maximum severity), giving an AERI of 0.442. One AE was deemed related to IgPro10 treatment. Three patients experienced temporally associated AEs. No serious AEs or deaths were reported. Nine patients (90%) who completed the study tolerated flow rates of ≥ 8 mg/kg/min; 5 tolerated 12 mg/kg/min (7.2 mL/kg/h), translating into a threefold decrease in mean infusion time. IgPro10 was well tolerated at a flow rate of up to 12 mg/kg/min. Safety and tolerability findings were consistent with previously reported studies in non-Japanese patients with PID.

Efficacy and safety of human intravenous immunoglobulin 5% (Ig VENA) in pediatric patients affected by primary immunodeficiency

Patients affected by primary immunodeficiencies are characterized for high susceptibility for severe infections. Our data demonstrate Kedrion 5% intravenous immunoglobulin G (IVIg) treatment effective and safe as replacement therapy for children and adolescents affected by primary immunodeficiency. The particularities of our study are the selection of a long period of follow-up (71 patient-years of follow-up), and to the best of our knowledge, our study is one of few that assesses the safety and efficacy of intravenous immunoglobulin treatment of primary immunodeficiency specifically in a pediatric population.

A Systematic Review and Meta-regression Analysis on the Impact of Increasing IgG Trough Level on Infection Rates in Primary Immunodeficiency Patients on Intravenous IgG Therapy

PURPOSE

We conducted a systematic review and meta-regression analysis to evaluate the impact of increasing immunoglobulin G (IgG) trough levels on the clinical outcomes in patients with PID receiving intravenous immunoglobulin G (IVIG) treatment.

METHODS

Systematic search was conducted in PubMed and Cochrane. Other relevant articles were searched by reviewing the references of the reviewed article. All clinical trials with documented IgG trough levels and clinical outcome of interest in patients receiving IVIG treatment were eligible to be included in this review. Meta-regression analysis was conducted using Comprehensive Meta-analysis Software. Additional sensitivity analyses were undertaken to evaluate the robustness of the overall results.

RESULTS

Twenty-eight clinical studies with 1218 patients reported from year 2001 to 2018 were included. The mean IVIG dose used ranges from 387 to 560 mg/kg every 3 to 4 weekly, and mean IgG trough obtained ranges from 660 to 1280 mg/dL. Random-effects meta-regression slope shows that IgG trough level increases significantly by 73 mg/dL with every increase of 100 mg/kg dose of IVIG (p < 0.05). Overall infection rates reduced significantly by 13% with every increment of 100 mg/dL of IgG trough up to 960 mg/dL (p < 0.05).

CONCLUSION

This meta-analysis concludes that titrating the IgG trough levels up to 960 mg/dL progressively reduces the rate of infections, and there is less additional benefit beyond that. Further studies to validate this result are required before it can be used in clinical practice.

A New Intravenous Immune Globulin: Novel or Not?

OBJECTIVE

To assess the clinical use and determine the place in therapy for immune globulin intravenous (IV), human-slra, a recently approved IV immune globulin for the treatment of primary immune deficiency diseases (PIDD).

DATA SOURCES

A PubMed and MEDLINE search (2010 to April 2020) was conducted for relevant articles. Data were also obtained from the package insert.

STUDY SELECTION AND DATA EXTRACTION

English language publications regarding the clinical efficacy and safety of immune globulin-slra were analyzed. Publications focused on use of immune globulin products were also included.

DATA SYNTHESIS

Immune globulin-slra is indicated for patients with PIDD and was specifically developed to include donor plasma with high respiratory syncytial virus (RSV) antibody titers. Efficacy was demonstrated through favorable incidence of infections and infection-related complications. Patients treated with immune globulin-slra had increases in anti-RSV neutralizing antibody titers compared with baseline. Adverse events occurred at rates similar to or less than other available immune globulin products.

RELEVANCE TO PATIENT CARE AND CLINICAL PRACTICE

This review describes a new immune globulin product available for use in patients with PIDD. A novel approach to managing patients at risk of serious infections may be to utilize products with formulations proven to not only boost IgG levels, but also antibodies to specific pathogens.

CONCLUSIONS

The choice of which immune globulin product to select for a patient or formulary is complex. Each product is unique, and differences between products should be taken into consideration, along with cost and availability.

Pharmacometric Analysis of IgPro10 in Japanese and Non-Japanese Patients With Primary Immunodeficiency

PURPOSE

Immunoglobulin (Ig) G replacement therapy, administered intravenously (IVIG) or subcutaneously (SCIG), is the standard treatment in patients with primary immunodeficiencies (PID). We aimed to characterize the pharmacokinetic (PK) characteristics of serum IgG following administration of IgPro10 every 3 or 4 weeks in Japanese patients with PID, and compare with PK in non-Japanese patients. A previously developed population PK (PPK) model was validated, and predicted parameters were compared with the results from the clinical study.

METHODS

The previously developed PPK model, containing IgG concentration data from 5 non-Japanese studies, was supplemented with data from 3 Japanese studies of IgPro10 or IgPro20 to compare the IgG PK parameters between Japanese and non-Japanese patients. The model was externally validated by simulating IgG concentration-time profiles in Japanese patients to predict serum IgG PK characteristics and to compare them with observed Japanese PK data from Study IgPro10_3004.

FINDINGS

The analysis included 4502 serum IgG concentration values (from 34 Japanese and 168 non-Japanese patients). PPK estimates from the current analysis demonstrated a clearance (CL) of 0.139 L/d, central volume (V2) of 4.01 L, inter-compartmental clearance (Q) of 0.30 L/d, and peripheral volume of 3.51 L. These results were consistent with those from the previously published PPK model, with similar bootstrap means and 95% CIs. Goodness-of-fit criteria indicated that the final PPK model was consistent with observed data, with no systemic bias in model prediction. Prediction-corrected visual predictive checks confirmed a good description of data on both SCIG and IVIG. PK parameters were equivalent between Japanese and non-Japanese patients. Body weight was determined to be a significant covariate on both CL and V2. Simulated and observed AUC and maximum and minimum serum IgG concentrations were similar, with 90% CIs overlapping between simulated and observed IgG concentrations in Japanese patients.

IMPLICATIONS

PK parameter estimates of serum IgG were similar between Japanese and non-Japanese patients with PID. The PPK model, updated with Japanese data, was consistent with the previously published PPK model and could accurately predict both individual and population serum IgG concentration-time profiles following IgPro10 IV infusions every 3 or 4 weeks. EudraCT identifier: 2016-001631-12.

Pharmacokinetic properties of Privigen® in Japanese patients with primary immunodeficiency

This prospective, Phase 3, open-label, study (EudraCT: 2016-001631-12) evaluated pharmacokinetic (PK) characteristics of 3-/4-weekly Privigen^® (IgPro10, CSL Behring, King of Prussia, PA, USA) in Japanese patients with PID. PK parameters including serum trough immunoglobulin (IgG) level before next infusion during the wash-in/wash-out phase (C_trough), area under the concentration-time curve from time point zero to the last time point with quantifiable concentration (AUC_0-last), dose-adjusted AUC_0-last (dAUC), lowest and highest observed IgG levels (C_min, C_max), time to reach C_max (T_max), and total clearance (CL) were analyzed for both regimens of Privigen^® (dose: 138-554 mg/kg body weight). Ten patients were included in this analysis (3-/4-weekly: n = 2/n = 8). C_trough levels achieved ranged 7.96-10.05 g/L. C_max was observed approximately 1 h after the start of the infusion in both regimens. Mean (SD [not applicable for 3-weekly data]) PK parameters: C_max, 16.60 and 14.20 (5.53) g/L; C_min, 10.60 and 8.53 (3.89) g/L; AUC_0-last, 5971 and 6591 (2633) g*h/L; dAUC, 0.41 and 0.46 (0.19) g*h/L/mg; CL, 2.53 and 2.53 (1.00) mL/h and median T_max was 1.19 and 1.14 h, for 3-/4-weekly dosing regimens, respectively. Privigen^® PK characteristics in Japanese patients were similar between dosing regimens and to previously-reported results in non-Japanese patients with PID.

Longitudinal changes in measles antibody titers in plasma donors and minimum antibody levels of immunoglobulin products for treatment of primary immunodeficiency

BACKGROUND

To ensure that immunoglobulin (Ig) products have adequate functional antibody, the US Food and Drug Administration (FDA) requires that Ig lots contain minimum levels of measles neutralizing antibody; the current minimum is 0.48 x US Reference Ig 176.

STUDY DESIGN AND METHODS

In the first part of the study, measles antibody titers were measured in donor plasma samples collected in 2007, 2011, and 2017. In the second part, trough or steady-state serum levels of measles neutralizing antibody were measured in two studies of patients with primary immunodeficiency (PID) who were treated with intravenous (Study 1; N = 46) or subcutaneous (Study 2; N = 18) Ig replacement therapy, meeting previous requirements for lot potency (≥0.6 x US Reference Ig 176). Serum measles neutralizing antibody titers were then estimated for conditions in which the potency of the Ig replacement product was 0.48 or 0.30 x US Reference Ig 176.

RESULTS

Measles antibody titers in donated plasma samples declined in donors born after 1963. In the two studies of patients with PID who were treated with intravenous or subcutaneous Ig replacement therapy, all patients exhibited trough (intravenous Ig) or steady-state (subcutaneous Ig) measles neutralizing antibody titers above 0.12 IU/mL, which has been shown to protect against clinical measles in the general population. Estimates suggest that all patients except one would have continued to meet this standard if the Ig lot potency had been 0.48 or 0.30 x US Reference Ig 176.

CONCLUSION

These studies provide supporting evidence that the lot release specification can be safely lowered from 0.48 to 0.30 x US Reference Ig 176, which will accommodate declining measles neutralizing antibody levels in donor plasma.

Treatment Satisfaction with Subcutaneous Immunoglobulin Replacement Therapy in Patients with Primary Immunodeficiency: a Pooled Analysis of Six Hizentra® Studies

Purpose

Primary immunodeficiency diseases (PIDDs) are a heterogenous group of disorders characterized by intrinsic impairment in the immune system. Most patients with PIDD require life-long immunoglobulin G replacement therapy, which has been shown to reduce the rate of infections and, related hospitalizations and reduce health-related quality of life (HRQOL). Here, treatment satisfaction and HRQOL in patients with PIDD was evaluated upon switching from intravenous (IVIG) or subcutaneous immunoglobulins (SCIGs) to 20% SCIG (Hizentra®), and during long-term steady-state Hizentra® treatment.

Methods

Analyses were based on two pivotal (switch) and four extension/follow-up (maintenance) Phase III studies of Hizentra® conducted in Europe (EU), Japan (JP), and the United States (US). Two validated questionnaires were used: Life Quality Index (LQI) for assessment of IgG-specific perceptions of HRQOL and Short Form 36 version 2 (SF-36v2).

Results

In the EU and JP switch studies, there was significant and meaningful improvement from Screening in LQI domain scores at all time points, largely driven by patients switching from IVIG to SCIG. In the EU switch study, there were also significant increases in mean SF-36v2 domain scores for Physical Function and General Health from Screening to Week 12. These improvements were observed also at Week 24. Overall, LQI and SF-36v2 domain scores were generally sustained in the maintenance studies.

Conclusions

These results showed that switching patients from IVIG to SCIG improves patient self-reported health status and IgG-specific HRQOL perception. The maintenance studies generally showed no deterioration of this improved health status over a long follow-up period.

Electronic supplementary material

The online version of this article (10.1007/s10875-018-0562-3) contains supplementary material, which is available to authorized users.

Long-Term Efficacy and Safety of Hizentra® in Patients with Primary Immunodeficiency in Japan, Europe, and the United States: a Review of 7 Phase 3 Trials

Many patients with primary immunodeficiency (PID) require immunoglobulin G (IgG) replacement therapy, delivered as intravenous IgG (IVIG) or subcutaneous IgG (SCIG). We aim to identify trends in efficacy and safety that would not be evident in individual studies of small patient numbers. Seven open-label, Phase 3, prospective, multicenter studies of the efficacy and safety of Hizentra® (a SCIG), conducted in Japan, Europe, and the US were summarized. Overall, 125 unique patients received 15,013 weekly infusions during a total observation period of 250.9 patient-years. Mean weekly doses of Hizentra® were 83.22–221.3 mg/kg body weight; infusion rates per patient (total body rate) were 25.2–49.3 mL/h across studies. The rates of infections and serious bacterial infections were 3.10 and 0.03 events per patient/year, respectively. Annualized rates of days hospitalized due to infection, out of work/school, and prophylactic antibiotic use were 0.95, 5.14, and 36.78 per patient, respectively. For the equivalent monthly dose, weekly Hizentra® SCIG administration resulted in expectedly-increased serum IgG trough levels in patients switching from IVIG, and maintained levels in patients switching from previous SCIG. Adverse events (AEs) totaled 5039 (events/infusion 0.094–0.773), almost all of which were mild/moderate. Three thousand one hundred ninety-seven were considered treatment-related, the most common of which were injection site reactions (2919 events; 0.001–0.592 AEs per infusion). Systemic AEs were very uncommon. The results from these seven studies indicate that Hizentra® therapy was both efficacious and well tolerated during long-term treatment. This is particularly important in patients with PID, who may require lifelong IgG replacement therapy.

Individualized immunoglobulin treatment in pediatric patients with primary humoral immunodeficiency disease

Primary immunodeficiency diseases (PIDD) are a group of genetic conditions that are generally considered to be under-diagnosed, and gaps may exist in the knowledge of treatment options. This review focuses on the diagnosis of pediatric patients with primary antibody deficiency and considerations for treatment with immunoglobulin (IgG) to optimize multiple dosing variables and minimize adverse events. The possibility of individualizing IgG therapy in clinical practice represents, in this field, the next pivotal step with the goal of improving the quality of life of pediatric patients with PIDD.

Surveillance study on the tolerability and safety of Flebogamma® DIF (10% and 5% intravenous immunoglobulin) in adult and pediatric patients

Direct comparisons of tolerability and safety of concentrated intravenous immunoglobulin (IVIG) versus less concentrated products are scarce. In this postauthorization, prospective, observational, multicenter study, a systematic comparison of 10% and 5% concentrations of Flebogamma® DIF IVIG was performed in both adult and pediatric patients treated with the studied IVIG products according to the approved indications under routine conditions. Dose of product administered, adverse events (AEs), physical assessments, laboratory tests, and concomitant therapy were analyzed. Patient recruitment in the 10% and 5% product groups was, respectively, 34 (32 analyzed, 13 of them children, receiving 130 IVIG infusions) and 35 (34 analyzed, receiving 135 IVIG infusions). Twenty‐four infusions (18.5%; 95% CI: 11.8, 25.1) with the 10% product and 3 (2.2%; 95% CI: −0.3, 4.7) with the 5% product were associated with potentially treatment‐related AEs (P < 0.0001). Nine patients (28.1%) infused with the 10% product and 3 (8.8%) infused with the 5% product presented, respectively, 33 and 8 treatment‐related AEs (of which 7 and 6, respectively, were serious AEs, experienced by only three hypersensitive patients). The profile of AEs occurring with the infusion of 10% and 5% products were comparable. The most frequent treatment‐related AEs were headache (n = 17, 3 patients; 15 episodes, 1 patient) and pyrexia (n = 6, 4 patients). In conclusion, no unpredictable risk was detected for both Flebogamma DIF 10% and 5% concentrations, which were therefore deemed as safe and well‐tolerated IVIG in the studied population. The frequency of infusions associated with treatment‐related AEs was lower with the 5% concentration.

Efficacy and Safety of Human Intravenous Immunoglobulin 10% (Panzyga®) in Patients with Primary Immunodeficiency Diseases: a Two-Stage, Multicenter, Prospective, Open-Label Study

PURPOSE

To assess the efficacy and safety of panzyga® (intravenous immunoglobulin 10%) in preventing serious bacterial infections (SBIs) in patients with primary immunodeficiency diseases (PIDs), a prospective, open-label, multicenter, phase 3 study and an open-label extension study were undertaken.

METHODS

Initially, the study drug (infusion rate ≤0.08 mL/kg/min) was administered at intervals of 3 or 4 weeks for 12 months, followed by 3 months of panzyga® at infusion rates increasing from 0.08 to 0.14 mL/kg/min. The primary endpoint in the main study was the rate of SBIs per patient-year on treatment. Secondary outcomes included non-serious infections, work/school absence, episodes of fever, quality of life, and adverse events (AEs).

RESULTS

The main study enrolled 51 patients (35% female, mean age 26.8 years), with 21 participating in the extension study. The rate of SBIs per patient-year was 0.08 in the total population; there were four SBIs in the 4-weekly treatment group (2/30 patients) and none in the 3-weekly group (n = 21). Compared with 4-weekly treatment, 3-weekly treatment was associated with a higher rate of upper respiratory tract infections (RTIs), ear infections, and work/school absences, but a lower rate of lower RTIs and fever. Treatment was generally well tolerated; no AE led to treatment withdrawal or death.

CONCLUSIONS

Overall, the use of panzyga® in patients with antibody-deficient PID was associated with a low rate of AEs and was effective in preventing SBIs, exceeding US FDA and European Medicines Agency recommendations for efficacy.

A multicentre, prospective, non-randomized, sequential, open-label trial to demonstrate the bioequivalence between intravenous immunoglobulin new generation (IGNG) and standard IV immunoglobulin (IVIG) in adult patients with primary immunodeficiency (PID)

OBJECTIVES

To demonstrate the bioequivalence between 2 intravenous immunoglobulin (IVIG) preparations, TEGELINE^® and ClairYg^®, a ready-to-use 5% IVIG, in primary immunodeficiency (PID). Secondary objectives were to assess the efficacy, safety and pharmacokinetics of ClairYg^®.

METHODS

Twenty-two adult PID patients receiving stable doses of TEGELINE^® (5% lyophilized IVIG) were switched to ClairYg^® for 6 months. ClairYg^® was administered under the same conditions as TEGELINE^®, either every 3 or 4 weeks. The primary endpoint was mean average total IgG trough level at steady state with ClairYg^® versus TEGELINE^®. Clinical efficacy was also assessed in terms of infections and associated events.

RESULTS

Bioequivalence was established with a mean average total IgG trough level at steady state being 8.05g/L with TEGELINE^® and 9.17g/L with ClairYg^® (i.e. geometric mean for the difference between ClairYg^® and TEGELINE^® was 1.136; [90% CI: 1.092-1.181] P<0.001), within the pre-specified margin to establish bioequivalence (0.80-1.25). Total IgG trough levels remained clinically adequate (>4-6g/L) throughout the study. No patient was hospitalized for infection or had serious bacterial infections while receiving ClairYg^®. The median annualized infections rate per patient was similar for both products: 4.35 [0; 21.8] for TEGELINE^® and 4.30 [0; 15.1] for ClairYg^®. Infections were less common with higher IgG trough levels (>8.16g/L). ClairYg^® showed good safety, in particular good hepatic and renal tolerance, and did not induce hemolysis. ClairYg^® pharmacokinetics profile was comparable to that of TEGELINE^®.

CONCLUSION

ClairYg^® is safe and effective in the treatment of adult PID.

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.

Effect of IVIG Formulation on IgG Binding to Self- and Exo- Antigens In Vitro and In Vivo

In relation to the recent trials of Intravenous Immunoglobulin (IVIG) in Alzheimer’s Disease (AD) it was demonstrated that different IgG preparations contain varying amounts of natural anti-amyloid β (Aβ) antibodies as measured by ELISA. We therefore investigated the relevance of ELISA data for measuring low-affinity antibodies, such as anti-Aβ. We analysed the binding of different commercial Immunoglobulin G (IgG) preparations to Aβ, actin and tetanus toxoid in different binding assays to further investigate the possible cause for observed differences in binding to Aβ and actin between different IgG preparations. We show that the differences of commercial IgG preparations in binding to Aβ and actin in ELISA assays are artefactual and only evident in in vitro binding assays. In functional assays and in vivo animal studies the different IVIG preparations exhibited very similar potency. ELISA data alone are not appropriate to analyse and rank the binding capacity of low-affinity antibodies to Aβ or other endogenous self-antigens contained in IgG preparations. Additional analytical methods should be adopted to complement ELISA data.

Efficacy, Safety, and Pharmacokinetics of a New 10 % Liquid Intravenous Immunoglobulin Containing High Titer Neutralizing Antibody to RSV and Other Respiratory Viruses in Subjects with Primary Immunodeficiency Disease

PURPOSE

Immune globulins for IgG supplementation have been produced for over 35 years with essentially no differentiating features regarding their specific antibody composition. Furthermore, the compositions of plasma donor pools used for IG manufacturing are not standardized. While all immune globulin products meet the specifications set by the US FDA for antibodies to pathogens like measles and polio, they have variable levels of antibodies to other important viruses and infectious pathogens, particularly respiratory syncytial virus (RSV).

METHODS

An IVIG was developed that satisfies the requirements for treating patients with primary immune deficiency disease (PIDD) and also has standardized elevated levels of RSV neutralizing antibodies (RI-002). Plasma donors who have naturally occurring high circulating levels of neutralizing anti-RSV antibody were selected as the source for manufacturing IVIG to treat patients with PIDD to prevent serious bacterial infections. While the introduction of the monoclonal antibody Palivizumab has had a dramatic impact in diminishing the burden of RSV disease in the pediatric population, it does not meet the standards for replacing the deficient immune compartments of patients with PIDD.

RESULTS

Fifty-nine patients with PIDD at 9 different sites across the US were enrolled in this study and received regular infusions of RI-002 over the course of 1 year.

CONCLUSIONS

There were zero serious bacterial infections, thus meeting the primary endpoint for this trial. The secondary endpoints including days missed from work due to infection, unscheduled visits to the physician, and days of hospitalization due to infection compared favorably to published reports of other IVIG products.

Recombinant human hyaluronidase facilitated subcutaneous immunoglobulin treatment in pediatric patients with primary immunodeficiencies: long-term efficacy, safety and tolerability

AIM

To assess the long-term efficacy, safety and tolerability of recombinant human hyaluronidase-facilitated subcutaneous infusion of immunoglobulin (Ig) (fSCIG; HYQVIA(®); IGHy) in children aged <18 years.

PATIENTS & METHODS

Patients with primary immunodeficiency diseases were included in the studies. IGHy was administered every 3 or 4 weeks.

RESULTS

Validated acute serious bacterial infections were reported at 0.08/patient-year (four pneumonia episodes in three patients). No serious adverse drug reaction (ADR) was reported, and rates of local and systemic ADRs were low (0.09/infusion and 0.1/infusion). Infection rates were low (3.02/patient-year) with sustained Ig trough levels (median: 1009 mg/dl). Of 674 IGHy infusions, 97.2% required no change of administration due to ADR, in most (82.5%) with one infusion site. No patient developed neutralizing anti-rHuPH20 antibodies. Postpivotal study, 100% of patients aged <14 years or their caregivers and 85.7% of patients aged 14 to <18 years expressed preference for IGHy compared with Ig administered intravenously or Ig administered subcutaneously.

CONCLUSION

These studies, with the longest (maximum: 3.3 years) duration of any reported Ig replacement trials in children with primary immunodeficiency diseases, showed low infection, local and systemic reaction rates along with well-tolerated infusions given in a single site.

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.

Efficacy and safety of Gammaplex(®) 5% in children and adolescents with primary immunodeficiency diseases

This open-label multi-centre study evaluated Gammaplex(®) 5%, a human intravenous immunoglobulin (IVIG) 5% liquid, in 25 children and adolescent patients (aged 3-16 years) with primary immunodeficiency diseases (PIDs). Subjects received Gammaplex 5% (at doses of 300-800 mg/kg/infusion) for 12 months, with a 3-month follow-up. The primary efficacy end-point was the incidence of serious acute bacterial infections (SABIs) during the 12-month treatment period. Secondary objectives assessed safety and tolerability. Nineteen males and six females were treated using the same infusion schedule as their prior IVIG treatment (14 and 11 subjects on 21- and 28-day dosing schedules, respectively). Two SABIs of pneumonia were reported, resulting in an annual SABI event rate of 0·09 [upper one-sided 99% confidence interval (CI) = 0·36]. Twenty-one subjects (84%) experienced ≥ 1 infection during the study, with a median infective episode per subject/year of 3·08 (range  = 0-10·4). Sixteen subjects (64%) missed ≥ 1 day of nursery or school because of infection or other illness. All trough immunoglobulin G levels exceeded 7·00 g/l after 15 weeks (mean = 9·69 g/l; range = 7·04-15·35 g/l). Product-related adverse events occurred in 14 subjects (56%); none were serious. Of 368 total infusions, 97 (26%) were associated temporally with an adverse event (≤ 72 h after infusion), regardless of causality. Laboratory test results and adverse-reaction data showed no evidence of product-related haemolysis or thromboembolic events. These data demonstrate that Gammaplex 5% is effective in preventing SABIs and well tolerated in children and adolescents with PID.

[A place of intravenous immunoglobulins in current clinical practice: Privigen is a novel 10% immunoglobulin]

Intravenous immunoglobulins (IVIGs) were initially designed to treat patients with primary immunodeficiencies (PID). Due to the multidirectional effect of IVIGs on the immune system, a range of nosological entities, in which these agents are successfully administered, is steadily expanding. As of now, IVIGs are successfully used in neurology, rheumatology, hematology, and oncology and they are essential drugs for many patients. In spite of the long experience with IVIGs, their mechanism of action remains unclear, numerous investigations for their clinical introduction are being continued. Therefore, there is a growing need to increase the production of the drugs, which gives rise to the emergence of novel medications, which differ in their composition and manufacture technologies, on the pharmacological market. The 10% intravenous immunoglobulin privigen, the safety and efficacy of which has been proven in foreign practice, is a novel drug on the Russian market.

Quantitative Evidence of Wear-Off Effect at the End of the Intravenous IgG (IVIG) Dosing Cycle in Primary Immunodeficiency

PURPOSE

Intravenous IgG (IVIG) treatment wear-off is commonly experienced by patients, who report increased susceptibility to infection, and decreased quality of life towards the end of their 3- or 4-week dosing cycle, when serum IgG levels approach their trough. We quantified IVIG wear-off in terms of treatment efficacy and patient well-being.

METHODS

Data were collected from patients enrolled in three Phase III trials of Sandoglobulin NF Liquid or Privigen, treated every 3- or 4- weeks. Pooled analyses of raw patient data compared the rate of infection and other clinical outcomes during the course of the dosing cycle. Subjective symptoms of wear-off were quantified by comparing patient-reported overall well-being scores.

RESULTS

The probability of a first infection in the final week of the IVIG cycle was 1.26 (95% confidence intervals [CI]: 0.76-2.11; p = 0.3621) and 1.55 (95% CI: 1.04-2.32; p = 0.0314) times higher than in the first week, for patients on a 3-week cycle and 4-week dosing cycles, respectively. Wear-off, as manifested by a decrease in overall well-being, was experienced in 10% of all cycles and reported at least once by 61% of the patients on a 3-week cycle, and 43% of those on a 4-week cycle.

CONCLUSIONS

These findings confirm the existence of decreased efficacy (treatment wear-off) towards the end of a 3-4 week IVIG dosing cycle, and provide a quantifiable evaluation to a phenomenon typically reported anecdotally. For patients experiencing wear-off, increasing the IgG dose or shortening the dosing interval and/or a switch to SCIG may be beneficial.

The history and evolution of immunoglobulin products and their clinical indications

The history of providing antibodies to treat diseases began in the 19th century with the discovery of tetanus and diphtheria toxins and the demonstration that immunity to tetanus and diphtheria infections could be transferred by immune sera. Characterization of the mediators of this immunity resulted in the discovery that antibodies are proteins that can be isolated and used to protect against infectious diseases. Development of a method to isolate antibodies from human plasma that could be safely injected into people initiated the development of human gamma globulin preparations to provide antibodies to patients with inherited antibody deficiencies. To overcome the limitations imposed by intramuscular injection of gamma globulin, intravenous gamma globulin preparations were developed that began to be used in a wide variety of clinical conditions. Thus the original clinical indication for infection prevention was expanded to several other indications that employ large doses to suppress inflammatory and autoimmune disorders. The most recent development in immunoglobulin therapy is the production of concentrated immune globulins for subcutaneous injection. Home infusions of subcutaneous immunoglobulin are increasingly used to treat immunodeficient patients and are being studied for other clinical applications.

Efficacy and tolerability of 16% subcutaneous immunoglobulin compared with 20% subcutaneous immunoglobulin in primary antibody deficiency

Multiple subcutaneous immunoglobulin (SCIG) products are available to treat primary antibody deficiency (PAD). The efficacy and tolerability of 16% SCIG (Vivaglobin(®) ) was compared with 20% SCIG (Hizentra(®) ) in PAD subjects. The study was a prospective, single-centre, open-label study of PAD subjects transitioning Vivaglobin to equivalent Hizentra doses, rounded to the nearest vial size. Comparisons included immunoglobulin (Ig)G levels; tetanus, varicella and Streptococcus pneumoniae titres; adverse events (AEs), annual infection rate and quality of life during 8 weeks of Vivaglobin and 24 weeks of Hizentra. Thirty-two subjects (aged 2-75 years) participated. Rounding to the nearest Hizentra vial size resulted in a 12·8% (± 2·9%) increase in SCIG dose. Median immunoglobulin (Ig)G level following 8 weeks of Vivaglobin was similar to 24 weeks of Hizentra (1050 versus 1035 mg/dl, respectively; P = 0·77). Both products had similar protective titres to tetanus, varicella and serotypes of S. pneumoniae, which were variable but well above protective levels. After 12 weeks of Hizentra, subjects reported fewer local site reactions compared with Vivaglobin. Switching products resulted in increased systemic AEs in some subjects but, overall, not significantly higher than during Vivaglobin treatment. Average infusion time decreased from 104·7 min (3·3 sites) with Vivaglobin to 70·7 min (2·2 sites) with Hizentra (P = 0·0005). Acute serious bacterial infections were similar. Treatment satisfaction was superior with Hizentra. Hizentra and Vivaglobin have similar pharmacokinetics and efficacy. Although transition to a different SCIG product initially increased AEs, Hizentra is well tolerated and can be infused more rapidly and with fewer sites compared to Vivaglobin.

Subcutaneous Immunoglobulin Replacement Therapy with Hizentra® is Safe and Effective in Children Less Than 5 Years of Age

BACKGROUND

Hizentra® (IGSC 20%) is a 20% liquid IgG product approved for subcutaneous administration in adults and children 2 years of age and older who have primary immunodeficiency disease (PIDD). There is limited information about the use of IGSC 20 % in very young children including those less than 5 years of age.

METHODS

A retrospective chart review involved 88 PIDD infants and children less than 5 years of age who received Hizentra®.

RESULTS

The mean age at the start of Hizentra® was 34 months (range 2 to 59 months). IGSC 20 % was administered weekly to 86 infants (two additional infants received twice weekly and three times weekly infusions, respectively) and included an average of 63 infusions (range 6-182) for an observation period up to 45.5 months. Infusion by manual delivery occurred in 15 patients. The mean dose was 674 mg/kg/4 weeks. The mean IgG level was 942 mg/dL while on IGSC 20 %, compared to a mean trough IgG level of 794 mg/dL (p < 0.0001) during intravenous or subcutaneous IgG administration prior to IGSC 20 %. Average infusion time was 47 (range 5-120) minutes, and the median number of infusion sites was 2 (range 1-4). Local reactions were mostly mild and observed in 36/88 (41%) children. No serious adverse events were reported. A significant increase in weight percentile (7 % ± 19.2, p = 0.0012) among subjects was observed during IGSC 20% administration. The rate of serious bacterial infections was 0.067 per patient-year while receiving IGSC 20%, similar to previously reported efficacy studies.

CONCLUSIONS

Hizentra® is effective in preventing infections, and is well tolerated in children less than age 5 years.

Enhancing Patient Flexibility of Subcutaneous Immunoglobulin G Dosing: Pharmacokinetic Outcomes of Various Maintenance and Loading Regimens in the Treatment of Primary Immunodeficiency

Introduction

Standard treatment for patients with primary immunodeficiency (PID) is monthly intravenous immunoglobulin (IVIG), or weekly/biweekly subcutaneous immunoglobulin (SCIG) infusion. We used population pharmacokinetic modeling to predict immunoglobulin G (IgG) exposure following a broad range of SCIG dosing regimens for initiation and maintenance therapy in patients with PID.

Methods

Simulations of SCIG dosing were performed to predict IgG concentration–time profiles and exposure metrics [steady-state area under the IgG concentration–time curve (AUC), IgG peak concentration (C_max), and IgG trough concentration (C_min) ratios] for various infusion regimens.

Results

The equivalent of a weekly SCIG maintenance dose administered one, two, three, five, or seven times per week, or biweekly produced overlapping steady-state concentration–time profiles and similar AUC, C_max, and C_min values [95% confidence interval (CI) for ratios was 0.98–1.03, 0.95–1.09, and 0.92–1.08, respectively]. Administration every 3 or 4 weeks resulted in higher peaks and lower troughs; the 95% CI of the AUC, C_max, and C_min ratios was 0.97–1.04, 1.07–1.26, and 0.86–0.95, respectively. IgG levels >7 g/L were reached within 1 week using a loading dose regimen in which the weekly maintenance dose was administered five times in the first week of treatment. In patients with very low endogenous IgG levels, administering 1.5 times the weekly maintenance dose five times in the first week of treatment resulted in a similar response.

Conclusions

The same total weekly SCIG dose can be administered at different intervals, from daily to biweekly, with minimal impact on serum IgG levels. Several SCIG loading regimens rapidly achieve adequate serum IgG levels in treatment-naïve patients.

Electronic supplementary material

The online version of this article (doi:10.1007/s13554-014-0018-0) contains supplementary material, which is available to authorized users.

Clinical experience with an L-proline–stabilized 10 %intravenous immunoglobulin (Privigen®): real-life effectiveness and tolerability

Purpose

This retrospective study evaluated the effectiveness and tolerability in clinical practice of an L-proline–stabilized 10 % intravenous immunoglobulin (IVIG; Privigen®) in patients with primary (PID) or secondary immunodeficiency (SID).

Methods

Patients from 6 centers in Europe and the US were treated with individually determined regimens of Privigen® for ≥3 months. Serum immunoglobulin G (IgG) trough levels, annualized rates of infection, hospitalization and antibiotics use, and the incidence of adverse events (AEs) were analyzed.

Results

Of 72 patients, three infants with severe combined immunodeficiency (SCID) were analyzed separately. The remaining 69 patients (52.2 % male; median age 38 years [range: 0.1–90.0]) with PID (82.6 %) or SID (17.4 %) received a mean (±standard deviation) Privigen® dose of 532 ± 250 mg/kg/month resulting in trough serum IgG levels of 407–1,581 mg/dL (median: 954 mg/dL). Ten patients (14.5 %) experienced 11 serious bacterial infections over 22.0 ± 15.0 months of treatment (0.087 events/patient/year, upper one-sided 99 % confidence interval: 0.170), the most common being pneumonia (11.6 %). The rates for any infection and hospitalization were 1.082 events/patient/year and 3.63 days/patient/year, respectively. Two patients with severe disease accounted for 303 of 460 hospital days. Across all 72 patients, 13 (18.1 %) patients experienced AEs, including 10 (13.9 %) patients with AEs at least possibly related to Privigen®, including headache (8.3 %), fever, and chills (2.8 % each). No related serious AEs were reported. One infant with SCID died due to severe viral infection.

Conclusions

Despite the heterogeneous population, effectiveness and tolerability of Privigen® in clinical practice closely matched those reported in clinical studies.

A 10% liquid immunoglobulin preparation for intravenous use (Privigen®) in paediatric patients with primary immunodeficiencies and hypersensitivity to IVIG

BACKGROUND

The objective of this study was to evaluate safety and efficacy of Privigen®, a 10% intravenous immunoglobulin (IVIG), in a particular group of paediatric patients (highly sensitive to previous IVIG infusion) affected with Primary Immunodeficiencies (PID).

MATERIAL AND METHODS

Patients (n=8) from 3 to 17 years old diagnosed of PID who often suffered from adverse events related to the infusion to previous IVIG were switched to Privigen® in an open protocol. Data were prospectively collected regarding Privigen® administration: infusion, safety and efficacy. In parallel, data on safety and tolerance were retrospectively collected from medical charts regarding the previous 10% IVIG product used.

RESULTS

50% of the patients required premedication with previous IVIG. At the end of the study none required premedication with Privigen®. The infusion rate was lower than that recommended by the manufacturer. All patients had suffered through adverse events during previous IVIG infusion being severe in three patients and recurrent in the rest. With Privigen® only three patients suffered from an adverse event (all cases were milder than previous related). Trough levels of IgG remained stable. None suffer from any episode of bacterial infection.

CONCLUSION

The present work shows that Privigen® was safe in a group of hypersensitive paediatric patients who did not tolerate the administration of a previous 10% liquid IVIG by using a particular infusion protocol slower than recommended. The number of adverse effects was smaller than published, and all cases were mild. No premedication was needed. Privigen® was also effective in this small group.

A review on guidelines for management and treatment of common variable immunodeficiency

Common variable immunodeficiency (CVID) is the most common symptomatic primary immunodeficiency in adults. As symptoms of CVID are usually heterogeneous and unspecific, diagnosis and follow-up of CVID can be challenging. In light of this, a broad review of advances in management and treatment of CVID is performed here in order to reach a distinct protocol. However, it should be noted that owing to the nature of the disease, it can only be treated symptomatically but not cured. There is little evidence to guide appropriate or universal guidelines to improve the current status of management of the disease. The most satisfactory treatments of CVID could be achieved by the use of immunoglobulin replacement, antibiotics, immunosuppressants and hematopoietic stem cell transplantation. This review is written based on the importance of clinical surveillance of asymptomatic CVID cases and early recognition of different clinical complications. Moreover, for each complication, appropriate interventions for improving outcomes are mentioned.

Efficacy and safety of Privigen(®) in patients with chronic inflammatory demyelinating polyneuropathy: results of a prospective, single-arm, open-label Phase III study (the PRIMA study)

This prospective, multicenter, single-arm, open-label Phase III study aimed to evaluate the efficacy and safety of Privigen(®) (10% liquid human intravenous immunoglobulin [IVIG], stabilized with L-proline) in patients with chronic inflammatory demyelinating polyneuropathy (CIDP). Patients received one induction dose of Privigen (2 g/kg body weight [bw]) and up to seven maintenance doses (1 g/kg bw) at 3-week intervals. The primary efficacy endpoint was the responder rate at completion, defined as improvement of ≥1 point on the adjusted Inflammatory Neuropathy Cause and Treatment (INCAT) disability scale. The preset success criterion was the responder rate being ≥35%. Of the 31 screened patients, 28 patients were enrolled including 13 (46.4%) IVIG-pretreated patients. The overall responder rate at completion was 60.7% (95% confidence interval [CI]: 42.41%-76.43%). IVIG-pretreated patients demonstrated a higher responder rate than IVIG-naïve patients (76.9% vs. 46.7%). The median (25%-75% quantile) INCAT score improved from 3.5 (3.0-4.5) points at baseline to 2.5 (1.0-3.0) points at completion, as did the mean (standard deviation [SD]) maximum grip strength (66.7 [37.24] kPa vs. 80.9 [31.06] kPa) and the median Medical Research Council sum score (67.0 [61.5-72.0] points vs. 75.5 [71.5-79.5] points). Of 108 adverse events (AEs; 0.417 AEs per infusion), 95 AEs (88.0%) were mild or moderate in intensity and resolved by the end of study. Two serious AEs of hemolysis were reported that resolved after discontinuation of treatment. Thus, Privigen provided efficacious and well-tolerated induction and maintenance treatment in patients with CIDP.