Intravenous IgG Research Articles

Long-term safety and tolerability of hyaluronidase-facilitated subcutaneous immunoglobulin 10% as maintenance therapy for chronic inflammatory demyelinating polyradiculoneuropathy: Results from the ADVANCE-CIDP 3 trial.

Hyaluronidase-facilitated subcutaneous immunoglobulin (fSCIG) consists of subcutaneous human immunoglobulin G (IgG) 10% with recombinant human hyaluronidase (rHuPH20) and can be administered at the same dose and interval as intravenous IgG (IVIG). fSCIG recently received US approval as maintenance therapy for adults with chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) and European approval for adults and children with CIDP after stabilization with IVIG. ADVANCE-CIDP 3 (NCT02955355) was an open-label long-term extension of the Phase 3 double-blind randomized placebo-controlled ADVANCE-CIDP 1 study (NCT02549170) that examined fSCIG safety and efficacy as maintenance CIDP therapy. Primary outcomes were safety, tolerability, and immunogenicity. Efficacy was an exploratory outcome. The study provided 220 patient-years of follow-up data from 85 patients. Median (range) exposure was 33 (0-77) months. Patients received fSCIG every 4 weeks (88.2%) or every 3 weeks (11.8%). Median (range) 4-weekly IgG dose equivalent was 64.0 (28.0-200.0) g. Mean (standard deviation) infusion duration was 135.5 (62.8) minutes. Most adverse events (AEs) were mild or moderate and self-limiting. Of the 1406 AEs, only 48 were severe and 30 were serious. fSCIG-related AEs (n = 798) included infusion site reactions such as pain, redness, and pruritus. Three infusions (0.1%) were reduced in rate, interrupted, or stopped due to intolerability. Relapse occurred in 10 of 77 patients (13.0%); annual relapse rate was 4.5%. An anti-rHuPH20 antibody titer ≥1:160 was detected in 14 of 84 patients (16.7%); patients who tested positive (≥1:160) had similar relapse rates versus those who tested negative (16.7% vs. 12.3%, respectively). ADVANCE-CIDP 3 demonstrated favorable fSCIG long-term safety and tolerability consistent with its established safety profile, and a low relapse rate, supporting use as maintenance CIDP treatment.

Immunomodulatory and anti-inflammatory properties of immunoglobulin G antibodies.

Antibodies provide an essential layer of protection from infection and reinfection with microbial pathogens. An impaired ability to produce antibodies results in immunodeficiency and necessitates the constant substitution with pooled serum antibodies from healthy donors. Among the five antibody isotypes in humans and mice, immunoglobulin G (IgG) antibodies are the most potent anti-microbial antibody isotype due to their long half-life, their ability to penetrate almost all tissues and due to their ability to trigger a wide variety of effector functions. Of note, individuals suffering from IgG deficiency frequently produce self-reactive antibodies, suggesting that a normal serum IgG level also may contribute to maintaining self-tolerance. Indeed, the substitution of immunodeficient patients with pooled serum IgG fractions from healthy donors, also referred to as intravenous immunoglobulin G (IVIg) therapy, not only protects the patient from infection but also diminishes autoantibody induced pathology, providing more direct evidence that IgG antibodies play an active role in maintaining tolerance during the steady state and during resolution of inflammation. The aim of this review is to discuss different conceptual models that may explain how serum IgG or IVIg can contribute to maintaining a balanced immune response. We will focus on pathways depending on the IgG fragment crystallizable (Fc) as pre-clinical data in various mouse model systems as well as human clinical data have demonstrated that the IgG Fc-domain recapitulates the ability of intact IVIg with respect to its ability to trigger resolution of inflammation. We will further discuss how the findings already have or are in the process of being translated to novel therapeutic approaches to substitute IVIg in treating autoimmune inflammation.

Relapsing tumefactive demyelination lesions: A unique, distinct inflammatory brain pathology.

We report the case of a patient suffering from biopsy-proven relapsing tumefactive demyelinating lesions (TDLs) of the central nervous system who had five relapses in 16 years. No signs/symptoms suggestive of alternative pathologies emerged during the follow-up. A limited benefit was observed with intravenous (IV) high-dose steroids, while both plasma exchange and IV immunoglobulin G (IgG) administration were ineffective. A long-lasting (9 years) but transient clinical stabilization was obtained with cyclophosphamide. Our case supports the view that recurrent TDL is a relapsing brain inflammation not belonging to multiple sclerosis (MS) or myelin oligodendrocyte glycoprotein (MOG)-/AQP4-associated disorders. TDL concept and clinical features should be revised.

In-use stability of Rituximab and IVIG during intravenous infusion: Impact of peristaltic pump, IV bags, flow rate, and plastic syringes

This study investigates the impact of intravenous (IV) infusion protocols on the stability of Intravenous Immunoglobulin G (IVIG) and Rituximab, with a particular focus on subvisible particle generation. Infusion set based on peristaltic movement (Medifusion DI-2000 pump) was compared to a gravity-based infusion system (Accu-Drip) at different flow rates. The impacts of different diluents (0.9 % saline and 5.0 % dextrose) and plastic syringes with or without silicone oil (SO) were also investigated. The results from the aforementioned particular case demonstrated that peristaltic pumps generated high levels of subvisible particles (prominently < 25 µm), exacerbated by increasing flow rates, specifically in formulations lacking surfactants. Other factors, such as diluent type and syringe composition, also increased the number of subvisible particles. Strategies that can help overcome these complications include surfactant addition as well as the use of SO-free syringes and a gravity infusion system, which aid in reducing particle formation and preserving antibody monomer during administration. Altogether, these findings highlight the importance of the careful selection of formulations and infusion protocols to minimize particle generation during IV infusion both for patients’ safety and treatment efficacy.

Myeloperoxidase-ANCA IgG induces different forms of small vessel vasculitis based on type of synergistic immune stimuli

Anti-neutrophil cytoplasmic autoantibody (ANCA) vasculitis has diverse patterns of injury including microscopic polyangiitis (MPA), granulomatosis with polyangiitis (GPA), and eosinophilic granulomatosis with polyangiitis (EGPA). Necrotizing and crescentic glomerulonephritis (NCGN) occurs in all syndromes and as renal limited vasculitis (RLV). Single dose intravenous ANCA IgG-specific for mouse myeloperoxidase (MPO) causes RLV in mice. Although multiple mouse models have elucidated ANCA-IgG induced necrotizing and crescentic glomerulonephritis (NCGN), pathogenesis of ANCA-induced granulomatosis and vasculitis outside the kidney has not been clarified. To investigate this, we used intravenous MPO-ANCA IgG in the same strain of mice to induce different patterns of lung disease mirroring patients with granulomatosis with polyangiitis (GPA), microscopic polyangiitis (MPA), and eosinophilic granulomatosis with polyangiitis (EGPA). Repeated intravenous MPO-ANCA IgG induced GPA with NCGN, lung capillaritis, arteritis and granulomatosis. Lung leukocyte phenotypes were evaluated by immunohistochemical image analysis and by flow cytometry. ANCA lung capillaritis and microabscesses began within one day and evolved into granulomas in under seven days. Influenza plus single dose MPO-ANCA IgG induced MPA with NCGN, lung capillaritis and arteritis, but no granulomatosis. Allergic airway disease caused by house dust mites or ovalbumin plus single dose intravenous MPO-ANCA IgG induced EGPA with eosinophilic bronchiolitis, NCGN, capillaritis, arteritis, and granulomatosis. Thus, our study shows that the occurrence and pattern of lung lesions are determined by the same ANCA IgG accompanied by different synergistic immune factors.

New coronavirus infection SARS-CoV-2 in adult patients with inborn errors of immunity

BACKGROUND: Diagnosis and treatment of COVID-19 in patients with primary immunodeficiency, or inborn errors of immunity, are often challenging. AIM: Description of the COVID-19 course and therapy of adult patients with primary immunodeficiency treated in medical organizations of Moscow Healthcare Department. MATERIALS AND METHODS: We analyzed a cohort of 68 patients over 18 years (median ― 35 years) with primary immunodeficiency; 91% of patients have primary immunodeficiency with predominantly antibody deficiencies. Altogether 90 cases of the new СOVID-19 were analyzed: in 68 cases infection occurred for the first time, in 22 cases it recurred. The duration of the disease ranged from 3 to 80 days. Duration of PCR-positivity ranged from 0 to 59 days, median 8 days. RESULTS: Patients with Wuhan and Delta strains had more severe inflammatory signs according to C-reactive protein and lactate dehydrogenase, in patients with Wuhan lung involvement on CT-scam was larger. In demonstrated group of patients higher C-reactive protein correlated with larger lung involvement, longer duration of the disease and PCR-positivity, significant lymphopenia also correlated with higher C-reactive protein. To our data regularity of intravenous immunoglobulin therapy and IgG trough level didn’t correlate with infection severity and duration of the disease and virus-carriage. Indirectly, the change in the spectrum of medicine used in patients of the analyzed group coincided with the virus strain evolution. Anti-inflammatory therapy was mainly presented by dexamethasone and antagonists to interleukin 6 or its receptor (anti-IL-6): 55% and 73% for Wuhan, 63% and 50% for Delta, 17% and 39% for Omicron. Then, preference was gradually given to the target anti-cytokine medicine. Etiotropic antiviral therapy was more often used to treat infection caused by Wuhan and Delta strains ― 32% and 38%, respectively (in 17% for Omicron). With shifting toward immunotherapy by specific against COVID-19 immunoglobulins and monoclonal antibody to SARS-CoV-2: 5% and 9% for Wuhan, 0% and 75% for Delta, 48% and 83% for Omicron, respectively. Immune and etiotropic therapy was not carried out in Wuhan in 39%, in Delta in 43%, in Omicron in 41% of cases. The overall mortality rate from COVID-19 in the analyzed group was 3%. CONCLUSION: Patients with primary immunodeficiency represent a vulnerable group to the SARS-CoV-2 virus with a high risk of not only severe, but also a protracted and undulating course of infection, what must be taken into account for the correct interpretation of the patient's condition and the timely administration of the appropriate therapy.

#2244 Safety and efficacy of daratumumab monotherapy in lupus nephritis refractory to conventional and rescue therapies

Abstract Background and Aims Refractory lupus nephritis (LN) is defined as either no response to standard of care (SOC), i.e., failure to improve within 3–4 months or not achieving partial response within 12 months or complete response after 2 years of treatment. This condition is characterized by poor outcome, is often life-threatening, and represents a relatively unexplored clinical setting. A dysregulation of CD38 expression has been reported in Systemic lupus Erythematosus, and highly expressing CD38 plasma cells relegated in bone marrow niches inaccessible to conventional and biological agents could represent a source of repowering of the immune dysregulation. The efficacy and safety of daratumumab, a monoclonal antibody specifically directed at CD38, given without any other immunosuppressant or agents targeting B-cell-activating factor, were assessed in a discrete cohort of patients with refractory LN, in whom both SOC and rescue treatments had failed. Method Six patients (1 male and 5 females) aged 41.3 years (range 20 to 61 years) were treated with Daratumumab monotherapy. The treatment protocol consisted of 16 mg/kg daratumumab administered intravenously weekly for 8 weeks, then every two weeks 8 more times, and lastly monthly for 8 times. All patients had failed previous treatments with both SOC including either mycophenolate mofetil or cyclophosphamide-azathioprine, and rescue therapies including Rituximab, Ocrelizumab, Belimumab, and iv IgG. Results One out of six patients did not show clinical response after 6 months of therapy, and Daratumumab was discontinued. Five patients continued to be treated (total treatment maximum 22 infusions) and reached a 12-month observation. Renal biopsy performed before daratumumab administration revealed a class IV LN in 1 patient, class V LN in 1 patient, class III+V LN in 1 patient and class IV+V LN in the other 2. Three patients achieved a complete renal response and the other two a partial renal response. A significant decrease in proteinuria from 5.6 g per 24 h to 0.59 g per 24 h, 0.9 g per 24 h and 0.8 g per 24 h (P = 0.0010) at 3 months, 6 months and 12 months, respectively, was observed. The mean value of serum Creatinine (sCr) decreased from 2.3 to 1.5 mg/dl. The mean value of sCr decreased from 2.3 mg dl−1 to 1.5 mg/dl (P = 0.98) at 12 months. C3 and C4 levels increased from 72.8 (range, 0–99) to 101.6 (range, 78.0–135) mg/dl (P = 0.16) and from 9.4 (range, 5–14) to 20.4 (range, 13–30) mg/dl (P = 0.0182), respectively. A decrease in IgG mean levels from 971.7 mg dl−1 (range, 251–1546) to 512.3 mg/dl (range, 88–957), 481.7 (range, 84–878) mg/dl and 508.4 mg/dl (range, 192–685) at 3 months, 6 months and 12 months, respectively, was observed. Improvement of clinical symptoms was paralleled by seroconversion of anti-double-stranded DNA antibodies (p = 0.03), significant decrease in interferon-gamma values (p = 0.0006), BMCA-B-cell maturation antigen (p = 0.0005) and soluble CD163 levels (p = 0.045), and IL 10 levels (p = 0.0006). Clinical remission was substantiated by improvement of SLEDAI-2K score (p = 0.03). Daratumumab was generally well tolerated. Conclusion These data suggest that Daratumumab administered alone (i.e., without any other immunosuppressant or agents targeting B-cell activating factor) is highly effective in refractory LN. The multifaced effects of Daratumumab on the inflammatory burden and the interferon gamma profile could provide a restoration of the immune balance.

Greater mechanistic understanding of the cutaneous pathogenesis of Stevens-Johnson syndrome/toxic epidermal necrolysis can shed light on novel therapeutic strategies: a comprehensive review.

Stevens-Johnson syndrome/toxic epidermal necrolysis (SJS/TEN) are severe cutaneous adverse drug reactions (SCARs) characterized by widespread epithelial detachment and blistering, which affects the skin and mucocutaneous membranes. To date, therapeutic interventions for SJS/TEN have focused on systematic suppression of the inflammatory response using high-dose corticosteroids or intravenous immunoglobulin G (IgG), for example. No targeted therapies for SJS/TEN currently exist. Though our understanding of the pathogenesis of SJS/TEN has advanced from both an immunological and dermatological perspective, this knowledge is yet to translate into the development of new targeted therapies. Greater mechanistic insight into SJS/TEN would potentially unlock new opportunities for identifying or repurposing targeted therapies to limit or even prevent epidermal injury and blistering.

Three or four doses of intravenous immunoglobulin G treatment for isoimmune hemolytic disease: A case series and literature review.

Neonates affected by isoimmune hemolytic disease (HDN) are at risk of developing severe hyperbilirubinemia. Studies show that increasing levels of bilirubin impact neonatal neurodevelopment. To avoid complications associated with exchange transfusion, intravenous immunoglobulin G (IVIG) is used to treat hyperbilirubinemia. We included all infants who received more than two doses of IVIG treatment for isoimmune hemolytic disease. We analyzed the incidence of side effects associated with IVIG treatment and the rate of exchange transfusion. A retrospective chart review performed between October 2011-October 2022 at East Carolina University Health identified neonates who received more than two doses IVIG for HDN. Neonates of postmenstrual age greater than 28 days old, receiving less than three doses of IVIG or received IVIG for other indications were excluded. The occurrences of adverse events, demographics and use of other medical therapies were reviewed. Eleven neonates were included in the case series. Most common cause of severe hyperbilirubinemia was attributed to ABO incompatibility. Six patients (54%) received three doses of IVIG, and five patients (45%) received four doses of IVIG with bilirubin levels decreasing below exchange transfusion. No treatment exceeding four doses of IVIG was reported, nor adverse events during treatment. In this cohort of neonates with HDN, bilirubin levels decreased after treatment with multiple doses of IVIG. Future research on recommendations of optimal total number doses of IVIG to reduce the risk for exchange transfusion.

Successful management of severe Kell alloimmunization in pregnancy with intravenous immune globulin

Hemolytic Disease of the Fetus and Newborn (HDFN) is a condition that affects 1 to 2 out of 1000 patients during pregnancy (1). When an alloantibody is present, it is essential to identify its nature in order to organize appropriate follow-up. Kell-mediated HDFN is rare; it occurs in about 5% of Kell alloimmunized pregnant women. It is important to note that in case of anti-Kell immunization, the severity of HDFN is not correlated with maternal antibody titers, and anemia tends to occur earlier and more severely. Therefore, early diagnosing and management of this condition is crucial. In the management of severe fetal anemia due to Kell immunization, available treatments include in utero transfusion (IUT), immunoglobulin therapy. Other alternative treatments exist, such as plasmapheresis. Intravenous immunoglobulin (IVIG), a noninvasive therapeutic approach, acts through multiple mechanisms. IVIG has been evaluated in cases of RhD immunization with high maternal antibody titers and a history of pregnancies involving early hydrops or intrauterine death. Regarding the potential benefits of intravenous IgG therapy, it may delay the need for early IUT, reduce the overall reliance on IUT, and have a positive impact on obstetric outcomes. This case of IV IgG therapy of anti-Kell immunization offers a thought-provoking avenue for future exploration.

Critical Analysis of Thrombocytopenia Associated With Glycoprotein IIb/IIIa Inhibitors and Potential Role of Zalunfiban, a Novel Small Molecule Glycoprotein Inhibitor, in Understanding the Mechanism(s).

Thrombocytopenia is a rare but serious complication of the intravenous glycoprotein IIb/IIIa (GPIIb/IIIa; integrin αIIbβ3) receptor inhibitors (GPIs), abciximab, eptifibatide, and tirofiban. The thrombocytopenia ranges from mild (50 000-100 000 platelets/μL), to severe (20 000 to <50 000/μL), to profound (<20 000/μL). Profound thrombocytopenia appears to occur in <1% of patients receiving their first course of therapy. Thrombocytopenia can be either acute (<24 hours) or delayed (up to ~14 days). Both hemorrhagic and thrombotic complications have been reported in association with thrombocytopenia. Diagnosis requires exclusion of pseudothrombocytopenia and heparin-induced thrombocytopenia. Therapy based on the severity of thrombocytopenia and symptoms may include drug withdrawals and treatment with steroids, intravenous IgG, and platelet transfusions. Abciximab-associated thrombocytopenia is most common and due to either preformed antibodies or antibodies induced in response to abciximab (delayed). Readministration of abciximab is associated with increased risk of thrombocytopenia. Evidence also supports an immune basis for thrombocytopenia associated with the 2 small molecule GPIs. The latter bind αIIbβ3 like the natural ligands and thus induce the receptor to undergo major conformational changes that potentially create neoepitopes. Thrombocytopenia associated with these drugs is also immune-mediated, with antibodies recognizing the αIIbβ3 receptor only in the presence of the drug. It is unclear whether the antibody binding depends on the conformational change and whether the drug contributes directly to the epitope. Zalunfiban, a second-generation subcutaneous small molecule GPI, does not induce the conformational changes; therefore, data from studies of zalunfiban will provide information on the contribution of the conformational changes to the development of GPI-associated thrombocytopenia.

Preemptive intravenous human immunoglobulin G suppresses BK polyomavirus replication and spread of infection in vitro

BK polyomavirus (BKPyV) infection causes various diseases in immunocompromised patients. Cells from human lung and kidney were infected with BKPyV and treated with commercially available intravenous immunoglobulin G (IVIG). Its effects on BKPyV replication and spread of infection were investigated, focusing on administration timing. IVIG treatment 3 hours after infection suppressed BKPyV replication assessed by real-time PCR and expression of the viral capsid protein 1 and large T-antigen. IVIG effectively reduced the number of BKPyV-infected cells 2 weeks after infection in an antibody titer-dependent manner. Virus release in the culture supernatants was not influenced by IVIG treatment 6-80 hours and 3-9 days after infection. Collectively, IVIG did not affect viral release from infected cells but inhibited the spread of infection by neutralizing the released virus and blocking the new infected cell formation, indicating greater efficacy in early localized infection. BKPyV replication resumed in IVIG-treated cultures at 7 days after IVIG removal. Early prophylactic administration of IVIG is expected to reduce the growth and spread of BKPyV infection, resulting in the reduction of infected cell lesions and prevention of BKPyV-associated diseases.

Real-World Usage of Hyaluronidase-Facilitated Subcutaneous Immunoglobulin 10% in Patients with Multiple Myeloma Diagnosed with Secondary Immunodeficiency Disease

Introduction: In patients with mature B-cell malignancies such as multiple myeloma (MM), both the underlying disease and immunosuppressive therapy can result in patients developing secondary immunodeficiency disease (SID). SID often manifests in severe, recurrent, or persistent infections that can impair a patient's quality of life and are a major cause of morbidity and mortality in patients with MM, thereby resulting in significant clinical and socioeconomic burden. The use of immunoglobulin (Ig) replacement therapy is well established for the treatment of hypogammaglobulinemia in patients with primary immunodeficiency disease (PIDD). Hyaluronidase-facilitated subcutaneous immunoglobulin (fSCIG) 10% is a dual-vial unit of IgG 10% and recombinant human hyaluronidase (rHuPH20). fSCIG 10% is approved in the USA for the treatment of adults and children aged 2 years or older with PIDD, and in the EU for adults and children of any age with PIDD or SID. fSCIG 10% is not fully integrated into standard of care for patients with SID in many countries, in part owing to comparatively less familiarity of hematologists and oncologists with the evidence supporting the use of fSCIG 10% than for intravenous IgG therapy in patients with SID. Therefore, the HyMMy study (NCT05879757) aims to generate real-world evidence to gain a better understanding of patterns of fSCIG 10% use and outcomes in patients with MM and SID. Methods: HyMMy is a prospective, noninterventional, observational study that will be conducted at 30 centers in Europe and South America. It is planned for 100 patients to be enrolled and observed over a 12-month follow-up period. The overall duration of the study will be 38 months. Patients will be eligible for inclusion if they are aged 18 years or older, have a diagnosis of MM, and fulfill the diagnosis criteria for SID: patient suffers from severe, recurrent, or persistent infection despite appropriate anti-infective treatment, and has proven specific antibody failure or a serum IgG trough level of less than 4 g/L (excluding paraprotein). Patients may enter the study after being diagnosed with SID and no more than 30 days after fSCIG 10% treatment initiation, or with no more than 2 doses of fSCIG 10% already infused ( Figure). Patients newly starting fSCIG 10% have a 30-day window from enrollment to inclusion. Patients will be excluded if they have PIDD, have received Ig treatment or prophylaxis within 3 months of enrollment, have an ongoing serious infection requiring intravenous antimicrobial therapy, have a history of malignancy other than MM within 3 years of enrollment, or have had major surgery within 2 weeks of enrollment. The primary endpoint is to characterize the real-world infusion parameters of fSCIG 10% administration (dosing and administration characteristics; treatment interval; infusion volume, sites, rate, and duration; training visits; and fSCIG 10% discontinuation, interruption, or switch to other treatment). Secondary endpoints will examine the disease course and clinical management of MM (including overall survival and healthcare resource utilization) in patients treated with fSCIG 10%. The exploratory endpoints include: burden of infection; infection rate, type, duration, and severity; patient-reported outcomes pertaining to health-related quality of life, collected via questionnaire at the patients' visit; and overall physician assessment of fSCIG 10% utilization, tolerability, and effectiveness, as measured by a 5-point Likert scale questionnaire. Results: Patient recruitment started in June 2023. Interim analysis is planned after enrollment of the first 50 patients, and the estimated end of the study is 2026. Conclusions: HyMMy is the first prospective, observational study that focuses on the assessment of fSCIG 10% utilization patterns in adults with MM diagnosed with SID. The study will help to improve understanding of the treatment patterns and options available for patients with SID and hematologic malignancies, in particular MM. Takeda Development Center Americas, Inc. funded this study. Takeda Pharmaceuticals International AG funded writing support.

A comprehensive evaluation of arginine and its derivatives as protein formulation stabilizers

Arginine and its derivatives (such as arginine ethyl ester and acetyl arginine) have varying degrees of protein aggregation suppressor effect across different protein solutions. To understand this performance ambiguity, we evaluated the activity of arginine, acetyl arginine, and arginine ethyl ester for aggregation suppressor effect against human intravenous immunoglobulin G (IgG) solution at pH 4.8. Both arginine and its cationic derivative arginine ethyl ester in their hydrochloride salt forms significantly reduced the colloidal and conformational stability (reduced kd and Tm) of IgG. Consequently, the monomer content was decreased with an increase in subvisible particulates after agitation or thermal stress. Furthermore, compared to arginine, arginine ethyl ester with one more cationic charge and hydrochloride salt form readily precipitated IgG at temperatures higher than 25 °C. On the contrary, acetyl arginine, which mostly exists in a neutral state at pH 4.8, efficiently suppressed the formation of subvisible particles retaining a high amount of monomer owing to its higher colloidal and conformational stability. Concisely, the charged state of additives significantly impacts protein stability. This study demonstrated that contrary to popular belief, arginine and its derivatives may either enhance or suppress protein aggregation depending on their net charge and concentration.

Clinical features of non-cirrhotic portal hypertension in patients with common variable immunodeficiency

We wished to summarize the clinical features of common variable immunodeficiency (CVID) complicated by non-cirrhotic portal hypertension (NCPH) and to deepen our understanding of it. The case data of CVID complicated with NCPH admitted to Peking Union Medical College Hospital from January 1983 to May 2021 were analyzed retrospectively to summarize their clinical characteristics. Six patients with CVID combined with NCPH (three of each sex; 16-45 years) were assessed. Four patients had portal hypertension. All patients had anemia, splenomegaly, a normal serum level of albumin and transaminases, and possibly increased levels of alkaline phosphatase and gamma-glutamyl transpeptidase. Two patients were diagnosed with esophagogastric fundic varices by gastroscopy. Two patients underwent splenectomy (which improved hematologic abnormalities partially). Four patients had autoimmune disease. Two cases were diagnosed with nodular regenerative hyperplasia (NRH) upon liver biopsy. Six patients were administered intravenous immunoglobulin-G (0.4-0.6 g/kg bodyweight) once every 3-4 weeks as basic therapy. Often, CVID complicated with NCPH has: (1) The manifestations of portal hypertension as the primary symptom. (2) Autoimmune-related manifestations. Imaging can provide important diagnostic clues. The etiology may be related to hepatic NRH and splenomegaly due to recurrent infections.

Continuous cold ethanol precipitation of immunoglobulin G from human plasma

Currently intravenous immunoglobulin G (IVIG) is manufactured by cold ethanol precipitation in batch, which results in a slow process with a high footprint due to the use of large tanks. A batch precipitation method using ethanol for the production of IVIG from “cryo-poor plasma”, a starting material obtained after removal of cryoprecipitate from thawed fresh frozen plasma was rendered into a continuous method using a tubular reactor. This reactor consisted of double jacketed stainless-steel tubes filled with static mixers for efficient cooling, because the heat transfer in stainless steel is very high. The pH adjusted, precooled plasma and ethanol were fed into a tubular reactor and cooled down to − 7 °C and precipitation was induced and completed after having left the reactor. The precipitate at the reactor effluent was harvested by tandem precoat filtration or pseudo continuous batch centrifugation. Yield and purity were in the same range as the batch precipitation method, with 95% yield. Even with a residence time of one minute, complete precipitation with same yield and purity could be achieved. A tubular reactor with a length of 3.5 m and 3.7 cm internal diameter would be suited to process 4000 L of plasma per day. This concept will be the basis to substantially shrink the plant footprint of new plants or be a way to intensify existing manufacturing plants.

Biochemical Characterization of a New 10% IVIG Preparation [IgG Next Generation (BT595)/Yimmugo®] Obtained from a Manufacturing Process Preserving IgA/IgM Potential of Human Plasma.

Human plasma is used for the generation of several life-saving drugs and contains valuable antibodies from the immunoglobulin classes IgG, IgM and IgA. Purified intravenous IgG solutions (IVIGs) form the majority of plasma-derived medicine to treat patients with various forms of immunodeficiencies. In conventional IVIG manufacturing processes, immunoglobulin classes IgM and IgA are often discarded as contaminants, but these antibody classes have been proven to be effective for the treatment of acute bacterial infections. Considering the increase in demand for human plasma-derived products and the ethical value of the raw material, a more resource-saving usage of human plasma is needed. Intensive research over the last decades showed that adverse reactions to IVIGs depend on the presence of thrombogenic factors, partially unfolded proteins, non-specific activation of the complement system, and blood group specific antibodies. Therefore, new IVIG preparations with reduced risks of adverse reactions are desirable. A new manufacturing process that yields two biologics was established and quality attributes of the new IVIG solution (Yimmugo®) obtained from this process are presented. Here, we provide a biochemical characterization of Yimmugo®, a new 10%IVIG preparation. It is derived from human blood plasma by a combined manufacturing process, where IgM and IgA are retained for the production of a new biologic (trimodulin, currently under investigation in phase III clinical trials). Several improvements have been implemented in the manufacturing of Yimmugo® to reduce the risk of adverse reactions. Gentle and efficient mixing by vibration (called "vibromixing") during a process step where proteins are at risk to aggregate was implemented to potentially minimize protein damage. In addition, a dedicated process step for the removal of the complement system activator properdin was implemented, which resulted in very low anticomplementary activity levels. The absence of measurable thrombogenic activity in combination with a very high degree of functional monomeric antibodies predict excellent efficacy and tolerability. Yimmugo® constitutes a new high quality IVIG preparation derived from a novel manufacturing process that takes advantage of the full therapeutic immunoglobulin potential of human plasma.

Surveillance of anti-SARS-CoV-2 antibodies in plasma pools and in immunoglobulin medicinal products manufactured since 2020 has shown high neutralizing activity against SARS-CoV-2 and current variants

BackgroundPatients with primary and secondary immunodeficiencies have shown an impaired humoral immune response to COVID-19 vaccination. It is therefore of paramount importance to investigate anti-SARS-CoV-2 antibody levels in plasma pools and in immunoglobulin (IgG) products used to treat these patients. AIM: To assess the evolution of anti-SARS-CoV-2 antibodies (S protein) in plasma pools and IgG products and its neutralizing activity to original-type virus (Wuhan) and the variants of concern (VOC), including Omicron. MethodsHealthy donors plasma pools collected in the US and Europe, and the subsequent intravenous (Flebogamma DIFand Gamunex-C, Grifols) and subcutaneous (Xembify, Grifols) IgG manufactured batches were followed from March 2020. Anti-SARS-CoV-2 S protein IgG titers were determined in plasma pools and in IgG batches by ELISA. Neutralization assays analyzed the capacity of IgG products to neutralize original-type virus and VOC (Alpha, Beta, Delta, Omicron BA.1 and BA.5), using pseudo viruses expressing S protein. Results were expressed as the dilution producing 50% neutralization (ID50). ResultsIn plasma pools, anti-SARS-CoV-2 S antibodies continuously increased throughout the study period regardless of the geographic origin. In the US, the first positive plasma pools were collected at the end of 2020. Since July 2021, an exponential increase over 30-fold of anti-SARS-CoV-2 S antibodies was reported. This trend continued increasing until the end of study period. Similarly, IgG products showed a similar evolution of anti-SARS-CoV-2 S antibodies. As expected, IgG batches released at the end of 2020 presented low SARS-CoV-2 neutralization activity. However, IgG products manufactured since August 2021 showed high neutralization activity against original-type virus and the rest of VOC. Regarding Omicron BA.5, a 5 to 10-fold increase was observed over time. ConclusionThis study reported the onset of elevated anti-SARS-CoV-2 antibody titers in plasma pools and IgG products since mid-2021, reflecting the evolution of the pandemic and vaccine campaigns. Intravenous and subcutaneous IgG products efficiently neutralized the current circulating VOC, Omicron BA.5. Further research is warranted to assess whether a clinical protective titer against SARS-CoV-2 and passive immunization is achieved in patients with immunodeficiencies treated with IgG products.

The restorative effect of immunoglobulin G on indicators of cellular immunity in patients with co-infection drug-resistant tuberculosis/HIV with a CD4 lymphocyte cоunt from 200 to 50 cells/μL

Objective — to study the restorative effect of immunoglobulin G (IgG) in patients on indicators of cellular immunity in patients with drug-resistant tuberculosis (DR-TB)/HIV co-infection at the level of CD4+ lymphocytes from 200 to 50 cells/μL. Materials and methods. The study involved 52 patients aged 20 to 55 years, the average age was (37.2 ± 7.8) years. All patients were HIV-positive with laboratory-confirmed DR-TB with mycobacterium resistance to first- and second-line drugs. Patients on DR-TB/HIV were divided as follows: Group 1 (cont­rol) — 26 patients with DR-TB/HIV with the CD4 lymphocyte count from 200 to 50 cells/μL, who received standard treatment with second-line antimycobacterial therapy (AMBT) and antiretroviral therapy (ARVT); Group 2 (basic) — 26 patients with DR-TB/HIV with a CD4 lymphocyte count from 200 to 50 cells/μL, who also received standard treatment of second-line AMBD and ARVT, with the addition of complex therapy with intravenous IgG. Results and discussion. In patients of Group 2, at the end of the 20th month of treatment, the normalization of T-helpers level was noted in 69.2 % of people, which reached the average values of (830.0 ± 15.2) cells/μL, with an increase to a subnormal level (408,0 ± 1.6) cells/μL in 30.8 % of patients (p &lt; 0.05). Normalization of the T-helpers indicator in Group 1 was noted on the 20th month only in 42.3 % of people, and it amounted to (670.0 ± 14.5) cells/μL (р &lt; 0.05). The relative (percentage) level of the T-helpers indicator in the 20th month reached normal values in 61.5 % (р &lt; 0.05) of patients of Group 2, among patients of Group 1 — in 34.6 % of people (р &lt; 0.05 ). The absolute number of T-suppressors at the end of the 20th month decreased to the norm in 76.9 % of patients and 46.2 % of patients in Groups 2 and 1, respectively (p &lt; 0.05). In patients of Group 2, on the 20th month of treatment, the physiological level of the T-suppressors indicator (19—35) % was reached in 65.4 % of cases (р &lt; 0.05); in Group 1, the normal level was registered in 38.5 % of patients (p &lt; 0.05). The CD4+/CD8+ Ratio was below the norm in 100 % of patients of Group 1 during 14 months inclusive, and only on the 20th month it reached the norm in 23.1 % of patients (p &lt; 0.05). Group 2 patients had normalization in 57.7 % of cases at the 20th month (р &lt; 0.05). Conclusions. The additional use of intravenous IgG in the complex treatment of patients with DR-TB/HIV contributed to a faster recovery of the cellular link of immunity, which makes it possible to prescribe antiretroviral therapy to patients with DR-TB/HIV at an earlier time, prevent the development of systemic inflammation and improve the prognosis for survival.

Immunoglobulin for hemolytic jaundice in Japan: A retrospective survey.

Intravenous immunoglobulin G (IVIG) is used to treat blood-type incompatibility hemolytic disease of newborns (BTHDN). Although IVIG's efficacy for treating BTHDN has been challenged, as an updated systematic review suggests, IVIG could significantly reduce exchange transfusions. We conducted a mail-in questionnaire survey to ascertain actual use of IVIG for BTHDN in Japan. The survey, conducted in 2014, included infants born between January 1, 2009, and December 31, 2013. Questionnaires were sent to the heads of neonatal intensive care units (NICUs) at perinatal centers of the Japan Neonatologist Association. A total of 195 centers (64.6%) responded to the questionnaire. During the study period, 170 centers (87.2%) reported incidences of BTHDN. Among these centers, there were 1726 diagnosed cases of BTHDN in neonates. Of these cases, 419 infants were treated with IVIG in 127 centers, representing approximately 74.7% of all centers. After the exclusion of cases with missing data and those where consent for data usage was not obtained,a total916 infants were included in this study. Of these, 219 (23.9%) were treated with IVIG after phototherapy, and 187 (20.4%) of these infants did not require further blood exchange transfusion. The IVIG dosages ranged from 40 to 1200 mg/kg/dose, but the majority were between 500 and 1000 mg/kg/dose, with a median of 800 mg/kg/dose. About 20% of the infants treated with IVIG showed late-onset anemia and required treatment. Adverse events were reported in less than 1% of infants. For the treatment of BTHDN, IVIG administration was widely used in NICUs in Japan without severe adverse events.