Could Intravenous Immunoglobulin Collected from Recovered Coronavirus Patients Protect against COVID-19 and Strengthen the Immune System of New Patients?

The emergence of the novel coronavirus in Wuhan, China, which causes severe respiratory tract infections in humans (COVID-19), has become a global health concern. Most coronaviruses infect animals but can evolve into strains that cross the species barrier and infect humans. At the present, there is no single specific vaccine or efficient antiviral therapy against COVID-19. Recently, we showed that intravenous immunoglobulin (IVIg) treatment reduces inflammation of intestinal epithelial cells and eliminates overgrowth of the opportunistic human fungal pathogen Candida albicans in the murine gut. Immunotherapy with IVIg could be employed to neutralize COVID-19. However, the efficacy of IVIg would be better if the immune IgG antibodies were collected from patients who have recovered from COVID-19 in the same city, or the surrounding area, in order to increase the chance of neutralizing the virus. These immune IgG antibodies will be specific against COVID-19 by boosting the immune response in newly infected patients. Different procedures may be used to remove or inactivate any possible pathogens from the plasma of recovered coronavirus patient derived immune IgG, including solvent/detergent, 60 °C heat-treatment, and nanofiltration. Overall, immunotherapy with immune IgG antibodies combined with antiviral drugs may be an alternative treatment against COVID-19 until stronger options such as vaccines are available.

Naturally occurring autoantibodies against α-synuclein rescues memory and motor deficits and attenuates α-synuclein pathology in mouse model of Parkinson's disease.

It has been suggested that aggregation of α-synuclein (α-syn) into oligomers leads to neurodegeneration in Parkinson's disease (PD), but intravenous immunoglobulin (IVIG) which contains antibodies against α-syn monomers and oligomers fails to treat PD mouse model. The reason may be because IVIG contains much low level of antibodies against α-syn, and of which only a small part can penetrate the blood-brain barrier, resulting in an extremely low level of effective antibodies in the brain, and limiting the beneficial effect of IVIG on PD mice. Here, we first isolated naturally occurring autoantibodies against α-syn (NAbs-α-syn) from IVIG. Our further investigation results showed that NAbs-α-syn inhibited α-syn aggregation and attenuated α-syn-induced cytotoxicity in vitro. Compared with vehicles, NAbs-α-syn significantly attenuated the memory and motor deficits by reducing the levels of soluble α-syn, total human α-syn and α-syn oligomers, decreasing the intracellular p-α-synser129 deposits and axonal pathology, inhibiting the microgliosis and astrogliosis, as well as the production of proinflammatory cytokines, increasing the levels of PSD95, synaptophysin and TH in the brain of A53T transgenic mice. These findings suggest that NAbs-α-syn overcomes the deficiency of IVIG and exhibits a promising therapeutic potential for the treatment of PD.

Validation and implementation of Planova™ BioEX virus filters in the manufacture of a new liquid intravenous immunoglobulin in China.

There is a continuous need to improve the viral safety of plasma products, and we here report the development and optimization of a manufacturing-scale virus removal nanofiltration step for intravenous immunoglobulin (IVIG) using the recently introduced Planova™ BioEX filter. IVIG throughput was examined for various operating parameters: transmembrane pressure, temperature, protein concentration, and prefiltration methods. The developed procedure was based on filtering undiluted process solution (50.0 g/l IVIG) under constant transmembrane pressure filtration at 294 kPa and 25 °C following prefiltration with a 0.1 µm MILLEX VV filter. The recovery of IgG was approximately 98%, and no substantial changes in biochemical characteristics were observed before and after nanofiltration in scaled-up production. A viral clearance validation study with parvovirus under worst-case conditions performed at the National Institutes for Food and Drug Control of China (NIFDC) showed PPV logarithmic reduction value (LRV) > 4. Improved viral safety of IVIG can be assured by implementing a Planova BioEX nanofiltration step to ensure effective parvovirus clearance under conditions providing excellent protein recovery and no detectable impact on product biochemical properties. This plasma-derived IVIG product is the first to be certified for parvovirus safety by the NIFDC in China.

HPLC fingerprinting approach for raw material assessment and unit operation tracking for IVIG production from Cohn I+II+III fraction.

The plasma-derived IgG used either for diagnostic purpose or intravenous application (in form of IVIG) in various medical therapies is certainly gaining more and more attention on annual basis. Different manufacturing processes are used to isolate immunoglobulins from human plasma. However, a quest for alternative paths in IgG isolation not only requires development of the most efficient isolation process, but also a rapid and reliable analytics to track the purification. Fast and reliable fingerprint-based method for characterization of IgG prepared from Cohn I+II+III paste is presented in this paper. The fingerprint method bases on partial separation of proteins in linear gradient on CIMac™ quaternary amine, strong anion exchange group (QA) 0.1 mL column. Partial separation of proteins does not allow simple quantitative analysis of the samples during the IgG isolation from Cohn I+II+III fraction paste, but very accurate qualitative information about the composition of the sample can be obtained in less than 5 min. From the differences in the chromatograms of various samples, the ratio between IgG and impurities in each sample can be easily assessed. The method is suitable for input material control, in-line monitoring of the downstream processing, final control of the products, as well as in stability studies and enables taking fast and accurate decisions during fractionation process.

The dynamics of contract plasma fractionation.

Plasma Derived Medicinal Products (PMDPs) are an essential component of the modern therapeutic armamentarium. They are differentiated from most other medicines in several ways, particularly the unique nature of the raw material used for their manufacture. Human plasma has been fractionated to PDMPs for the past 75 years, and the economics of manufacturing requires currently that as many products are harvested from each litre as is feasible and reflective of clinical needs. PDMPs may be purchased on the open market from the various commercial and not-for-profit (NFP) manufacturers. They may also be manufactured under contract (CM) from plasma supplied by government and similar agencies as a product of blood transfusion services. Clients for CM aspire to make full use of donated plasma, hence maximizing the donors' gift after the standard components of transfusion have been harvested. Many such countries also aspire to making their national clinical needs self-sufficient in PDMPs, attempting to acquire strategic independence from the vagaries of the commercial open market. The increasing commercial imperatives operating in the PMDP sector generate a tension with such ethical aspirations which are not easily resolved. In particular, the need to harvest as many proteins as possible may generate products which are surplus to national needs, necessitating an ethical paradigm for the optimal provision of such products. In addition, traditional relationships between blood services and domestic fractionation agencies may come under stress as a result of the competitive processes underpinning such transactions, which are now subject to international norms of free trade. Blood services engaged in the supply of hospital transfusion components are detached from the pharmaceutical Good Manufacturing Practices (GMP) culture needed for the production of plasma for CM, while the generation of such plasma through extraction from whole blood donations deflects the focus from that of a dedicated raw material for CM to a byproduct of the donation process. We review the field of CM, assess the current tensions within the sector, and offer suggestions for the strategic positioning of governments and other clients to ensure optimal outcomes for all the stakeholders involved.

A new manufacturing process to remove thrombogenic factors (II, VII, IX, X, and XI) from intravenous immunoglobulin gamma preparations.

Coagulation factors (II, VII, IX, X, and particularly XIa) remaining in high concentrations in intravenous immunoglobulin (IVIG) preparations can form thrombi, causing thromboembolic events, and in serious cases, result in death. Therefore, manufacturers of biological products must investigate the ability of their production processes to remove procoagulant activities. Previously, we were able to remove coagulation factors II, VII, IX, and X from our IVIG preparation through ethanol precipitation, but factor XIa, which plays an important role in thrombosis, remained in the intermediate products. Here, we used a chromatographic process using a new resin that binds with high capacity to IgG and removes procoagulant activities. The procoagulant activities were reduced to low levels as determined by the thrombin generation assay: <1.56 mIU/mL, chromogenic FXIa assay: <0.16 mIU/mL, non-activated partial thromboplastin time (NaPTT): >250 s, FXI/FXIa ELISA: <0.31 ng/mL. Even after spiking with FXIa at a concentration 32.5 times higher than the concentration in normal specimens, the procoagulant activities were below the detection limit (<0.31 ng/mL). These results demonstrate the ability of our manufacturing process to remove procoagulant activities to below the detection limit (except by NaPTT), suggesting a reduced risk of thromboembolic events that maybe potentially caused by our IVIG preparation.

Effects of the manufacturing process on the anti-A isoagglutinin titers in intravenous immunoglobulin products.

BACKGROUND: The first intravenous immunoglobulin G (IVIG) preparations for clinical use were produced from human plasma by Cohn-like fractionation processes. To achieve higher purity and yield, chromatography-based processes were developed. Using two products as examples, we compare the capacity of these two manufacturing processes to reduce the levels of anti-A and anti-B isoagglutinins in IVIG, which are believed to be responsible for rare hemolytic adverse events. STUDY DESIGN AND METHODS: The isoagglutinin levels of Sandoglobulin (lyophilized, sucrose-stabilized IVIG produced by Cohn-like fractionation) and Privigen (10% l-proline-stabilized IVIG produced by a chromatography-based process) were measured by the indirect agglutination test (IAT). The intrinsic isoagglutinin reduction capacity of each fractionation step was assessed in laboratory- and industry-scale experiments using the IAT and a flow cytometry-based immunoglobulin-binding assay, respectively. RESULTS: The median anti-A isoagglutinin titer recorded in 248 Sandoglobulin lots was three titer steps lower than the one measured in 651 Privigen lots (1:2 vs. 1:16). Over the entire process, we measured a five-titer-step isoagglutinin reduction in laboratory-scale Cohn-like fractionation; the largest reduction was observed between Fraction (F)II+III and FII. An overall four-titer-step reduction was recorded in the industry-scale process. In contrast, none of the steps of the chromatography-based manufacturing process caused any decrease in anti-A isoagglutinin content. Similar results were obtained for anti-B isoagglutinin reduction. CONCLUSION: Unlike Cohn-like fractionation, chromatography-based IVIG manufacturing processes do not have an intrinsic capacity for isoagglutinin reduction. The addition of dedicated isoagglutinin reduction steps may help minimize the potential risk of hemolysis in IVIG-treated patients.

Anti-A and anti-B hemagglutinin depletion during Cohn purification process of 5% immunoglobulin.

BACKGROUND: Polyvalent immunoglobulin G (IgG) products obtained by fractionation of human plasma are widely used to treat a broad range of conditions, including immunodeficiency syndromes and autoimmune, inflammatory, and infectious diseases. For high-quality products and to minimize adverse events related to the use of intravenous IgG (IVIG) it is very important to perform detailed analyses of their components. One of these components, that in rare cases can cause severe hemolytic conditions, is the amount of hemagglutinins, natural antibodies that bind A and/or B (anti-A or -B) antigens present in red blood cells (RBCs). STUDY DESIGN AND METHODS: To characterize different IgG batches and to monitor the efficacy of the production procedure in the hemagglutinin reduction, a direct agglutination test (DAT) and a new flow cytometry (FC)-based assay were used for measuring the activity and the content of hemagglutinins in IgG samples obtained at different stages of the purification process. RESULTS: A total of 113 batches of 5% IVIG, produced in 2013 by Kedrion Biopharma, were analyzed for the ability to agglutinate RBCs by DAT. All batches tested were within the limits set by the European Pharmacopoeia. Three batches of 5% IVIG were analyzed for their hemagglutinin levels. The finished products and the production intermediates were evaluated by the DAT and the FC assay. A significant decrease of anti-A and anti-B titer after the Fraction (F)III precipitation was observed in all batches tested and an evaluation of the results obtained by the two methods was performed. CONCLUSIONS: This study shows that the hemagglutinin titer, accurately measured in a high number of 5% IVIG batches, is within the allowed limits for the DAT method. The specific production process employed, in particular the FIII precipitation step, successfully removes IgM and significantly reduces IgG class hemagglutinins.

Isoagglutinin reduction by a dedicated immunoaffinity chromatography step in the manufacturing process of human immunoglobulin products.

BACKGROUND: The passive transfer of antibodies specific to blood groups A and B (also called isoagglutinins) contained in immunoglobulin (Ig)G products for intravenous administration (IVIG) is believed to be largely responsible for rare but sometimes serious IVIG-related hemolytic events. We present in this work a modification of the manufacturing process of Privigen-a 10% l-proline-stabilized IVIG product-that allows extensive reduction of isoagglutinin concentrations in the final product. STUDY DESIGN AND METHODS: An additional immunoaffinity chromatography (IAC) step was introduced toward the end of the manufacturing process of Privigen. Isoagglutinin titers were measured using the indirect agglutination method and a published flow cytometry-based binding assay. Quality attributes, such as microorganism counts and concentration of endotoxins, IgG, IgA, IgM, aggregates, and so forth were measured using standardized procedures. RESULTS: The introduction of an IAC step in the manufacturing process of Privigen resulted in an 88% to 90% reduction in isoagglutinins between the feed of the chromatography column and the flow-through fraction. All other product quality attributes measured were nearly identical before and after IAC. This process modification resulted in a three-titer-step reduction in isoagglutinin levels in the final IgG product compared to Privigen lots produced by the unmodified process. CONCLUSION: Introducing an isoagglutinin-specific IAC step in the manufacturing process of Privigen is an efficient strategy for reduction of anti-A and anti-B titers. Such reductions might help minimize the risk of hemolytic events in patients receiving IVIG therapy.

Evaluation of intravenous anthrax immune globulin for treatment of inhalation anthrax.

Bacillus anthracis toxins can be neutralized by antibodies against protective antigen (PA), a component of anthrax toxins. Anthrivig (human anthrax immunoglobulin), also known as AIGIV, derived from plasma of humans immunized with BioThrax (anthrax vaccine adsorbed), is under development for the treatment of toxemia following exposure to anthrax spores. The pharmacokinetics (PK) of AIGIV was assessed in naive animals and healthy human volunteers, and the efficacy of AIGIV was assessed in animals exposed via inhalation to aerosolized B. anthracis spores. In the clinical study, safety, tolerability, and PK were evaluated in three dose cohorts (3.5, 7.1, and 14.2 mg/kg of body weight of anti-PA IgG) with 30 volunteers per cohort. The elimination half-life of AIGIV in rabbits, nonhuman primates (NHPs), and humans following intravenous infusion was estimated to be approximately 4, 12, and 24 days, respectively, and dose proportionality was observed. In a time-based treatment study, AIGIV protected 89 to 100% of animals when administered 12 h postexposure; however, a lower survival rate of 39% was observed when animals were treated 24 h postexposure, underscoring the need for early intervention. In a separate set of studies, animals were treated on an individual basis upon detection of a clinical sign or biomarker of disease, namely, a significant increase in body temperature (SIBT) in rabbits and presence of PA in the serum of NHPs. In these trigger-based intervention studies, AIGIV induced up to 75% survival in rabbits depending on the dose and severity of toxemia at the time of treatment. In NHPs, up to 33% survival was observed in AIGIV-treated animals. (The clinical study has been registered at ClinicalTrials.gov under registration no. NCT00845650.).

Inhibitory effect of IVIG on IL-17 production by Th17 cells is independent of anti-IL-17 antibodies in the immunoglobulin preparations.

PURPOSE: Th17 cells and their cytokines play a critical role in the pathogenesis of various autoimmune and inflammatory diseases. Recently, we have demonstrated that intravenous immunoglobulin (IVIG) suppresses differentiation, amplification, and functions of human Th17 cells. In this report we investigated whether IVIG inhibits IL-17 production by Th17 cells cultured in the presence of IL-23 and whether the inhibitory effect of IVIG on IL-17 production implicates anti-IL-17 antibodies. METHODS: Naive CD4(+) T cells were stimulated in the presence of TGF-ß, IL-21, and IL-23 for the differentiation of Th17 cells. Memory CD4(+) T cells were stimulated with IL-1ß, IL-6, and IL-23 for the amplification of Th17 cells. IVIG (0.15 mM) was added to the cells 12 h after initiation of cultures. IL-17A cytokine and anti-IL-17 antibodies were measured by ELISA. RESULTS: IL-23 did not deter the inhibitory effect of IVIG on IL-17 production from the differentiating and expanding Th17 cells. Further, suppression of IL-17 by IVIG did not implicate anti-IL-17 antibodies in the immunoglobulin preparations. CONCLUSION: The effect of IVIG on the inhibition of IL-17 production by Th17 cells is a consequence of modulation of Th17 cells and their intracellular signaling pathways and not due to passive neutralization of IL-17 by anti-IL-17 antibodies in the immunoglobulin preparations.

Flebogamma(®) DIF (intravenous immunoglobulin) purification process effectively eliminates procoagulant activities.

BACKGROUND: Studies have demonstrated that traces of activated factor XI (FXIa) present in specific brands of intravenous immunoglobulin (IVIG) concentrates may pose a thrombogenic risk. AIM: To characterize procoagulant activity during fractionation and the elimination capacity of the Flebogamma(®) DIF (Grifols' IVIG) manufacturing process. METHODS: Flebogamma(®) DIF fractionation steps included cryoprecipitate supernatant (Cryo/S), Fraction (Fr) I supernatant, and Fr II + III suspension. Purification steps included ultrafiltrate I, acid treatment, and pasteurization. Samples were assessed for total protein, IgG, and procoagulant activation markers. RESULTS: Cryo/S showed no procoagulant activity for prekallikrein activator (PKA), kallikrein-like, and non-activated partial thromboplastin time (NaPTT) with normal (-PPP) or FXI-deficient (-FXI) platelet poor plasma. Thrombin generation test (TGT)-PPP and TGT-FXI were <83-148 and <53-197 nM thrombin, respectively. Shortened NaPTTs (100-296 s), high PKA (51-119 IU/mL), kallikrein-like activities (0.043-0.075 ΔAU/min), positive TGTs (98-298 nM), and FXIa (9.5-14.0 ng/mL) were detected in Fr II + III. After pasteurization, no residual evidence of any procoagulant activity marker was observed, including the final IVIG concentrate at 5% or 10% protein. Results were similar in Fr II + III from different IVIG manufacturing facilities. CONCLUSIONS: The Flebogamma(®) DIF production process is capable of eliminating procoagulant activity because of its purification steps.

Chikungunya virus and the safety of plasma products.

BACKGROUND: Chikungunya virus (CHIKV) outbreaks were previously restricted to parts of Africa, Indian Ocean Islands, South Asia, and Southeast Asia. In 2007, however, the first autochthonous CHIKV transmission was reported in Europe. High-level viremia, a mosquito vector that is also present in large urban areas of Europe and America, and uncertainty around the resistance of this Alphavirus toward physiochemical inactivation processes raised concerns about the safety of plasma derivatives. To verify the safety margins of plasma products with respect to CHIKV, commonly used virus inactivation steps were investigated for their effectiveness to inactivate this newly emerging virus. STUDY DESIGN AND METHODS: Pasteurization for human serum albumin (HSA), vapor heating for Factor VIII inhibitor bypassing activity, solvent/detergent (S/D) treatment for intravenous immunoglobulin (IVIG), and incubation at low pH for IVIG were investigated for their capacity to inactivate CHIKV and the closely related Sindbis virus (SINV). The obtained results were compared to previous studies with West Nile virus and the commonly used model virus bovine viral diarrhea virus. RESULTS: The data generated demonstrate the effective inactivation of CHIKV as well as SINV by the inactivation steps investigated and thereby support results from earlier validation studies in which model viruses were used. CONCLUSION: High inactivation capacities with respect to CHIKV were demonstrated. This provides solid reassurance for the safety of plasma products and the results verify that the use of model viruses is appropriate to predict the inactivation characteristics of newly emerging viruses when their physicochemical properties are well characterized.

Virus reduction in an intravenous immunoglobulin by solvent/detergent treatment, ion-exchange chromatography and terminal low pH incubation.

Virus reduction by several steps in the manufacturing process for the intravenous immunoglobulin Vigam(®), has been investigated. The solvent/detergent step based on treatment with 0.3% tri-n-butyl phosphate and 1% polysorbate 80 at 37 °C, was confirmed to be effective for a range of enveloped viruses. Virus infectivity was undetectable i.e. >6 log inactivation within 30 min of the standard 6 h process. This was consistent over the range of conditions tested i.e. solvent/detergent and protein concentration, temperature and pH. The ion-exchange chromatography step in the process was also able to remove some viruses. Virus spiked followed by blank column runs confirmed the effectiveness of the sanitisation step for ensuring there was no virus cross contamination between column runs. The terminal low pH incubation step was also able to inactivate enveloped viruses, as well as some non-enveloped viruses. The combination of these three steps ensures a high margin of virus safety for this product.

Pharmacokinetics and safety of Intragam 10 NF, the next generation 10% liquid intravenous immunoglobulin, in patients with primary antibody deficiencies.

BACKGROUND AND AIMS: Intragam® 10 NF is the next generation 10% intravenous immunoglobulin with three pathogen reduction steps and a noncarbohydrate stabiliser. This open label, cross-over study in patients with primary immunodeficiency was designed to evaluate whether Intragam 10 NF differed in its pharmacokinetics (PK) compared with Intragam P and to assess Intragam 10 NF safety and tolerability. METHODS: Nineteen primary immunodeficiency patients were administered one cycle of their existing Intragam P dose (0.2-0.8 g/kg 3-4 weekly), followed by seven cycles of Intragam 10 NF administered at the same dosing schedule as Intragam P. The primary objective was to compare serum immunoglobulin G (IgG) trough levels. Secondary endpoints were PK variables, safety and tolerability. RESULTS: There was no significant within-patient difference in the average trough immunoglobulin G concentration between Intragam P and Intragam 10 NF (8.76 g/L, 8.55 g/L respectively) (geometrical mean ratio 1.034; 95% confidence interval 0.996-1.073; P = 0.079). Mean PK parameters for both products were similar, with all 95% confidence interval encompassing 1.0 except for time to maximum concentration. Time to maximum concentration occurred earlier with Intragam 10 NF compared with Intragam P, with a shorter infusion time (mean 1.75 h vs 2.52 h respectively; P < 0.05). Headache was the most frequent treatment-related event following both products. There were no study withdrawals, deaths, or notable changes in laboratory values or vital signs. CONCLUSION: Intragam 10 NF was well tolerated and exhibited similar PK to Intragam P, with the advantage of a 45 min shorter infusion time.

Production of hyperimmune anti-SARS-CoV-2 intravenous immunoglobulin from pooled COVID-19 convalescent plasma.

Background: This study assesses the feasibility of producing hyperimmune anti-COVID-19 intravenously administrable immunoglobulin (C-IVIG) from pooled convalescent plasma (PCP) to provide a safe and effective passive immunization treatment option for COVID-19. Materials & methods: PCP was fractionated by modified caprylic acid precipitation followed by ultrafiltration/diafiltration to produce hyperimmune C-IVIG. Results: In C-IVIG, the mean SARS-CoV-2 antibody level was found to be threefold (104 ± 30 cut-off index) that of the PCP (36 ± 8.5 cut-off index) and mean protein concentration was found to be 46 ± 3.7 g/l, comprised of 89.5% immunoglobulins. Conclusion: The current method of producing C-IVIG is feasible as it uses locally available PCP and simpler technology and yields a high titer of SARS-CoV-2 antibody. The safety and efficacy of C-IVIG will be evaluated in a registered clinical trial (NCT04521309).

Efficacy of intravenous immunoglobulin (IVIG) affinity-purified anti-desmoglein anti-idiotypic antibodies in the treatment of an experimental model of pemphigus vulgaris.

Pemphigus vulgaris is a rare life-threatening autoimmune bullous disease caused by immunoglobulin G (IgG) autoantibodies directed against desmogleins 1 and 3. Previously, we showed that intravenous immunoglobulin (IVIG) ameliorates anti-desmoglein-induced experimental pemphigus vulgaris in newborn naive mice. The aim of this study was to examine the efficacy of anti-anti-desmoglein-specific IVIG in a similar model. Pemphigus-vulgaris-specific IVIG (PV-sIVIG) was affinity-purified from IVIG on a column of single-chain variable fragment (scFv) anti-desmogleins 1 and 3. The anti-idiotypic activity of PV-sIVIG was confirmed by enzyme-linked immunosorbent assay, inhibition assay. After induction of pemphigus by injection of anti-desmogleins 1 and 3 scFv to newborn mice, the animals were treated with PV-sIVIG, IVIG (low or high dose) or IgG from a healthy donor (n = 10 each). The skin was examined 24-48 h later, and samples of affected areas were analysed by histology and immunofluorescence. In vitro study showed that PV-sIVIG significantly inhibited anti-desmogleins 1 and 3 scFv binding to recombinant desmoglein-3 in a dose-dependent manner. Specificity was confirmed by inhibition assay. In vivo analysis revealed cutaneous lesions of pemphigus vulgaris in mice injected with normal IgG (nine of 10 mice) or low-dose IVIG (nine of 10 mice), but not in mice treated with PV-sIVIG (none of 10) or high-dose IVIG (none of 10). On immunopathological study, PV-sIVIG and regular IVIG prevented the formation of acantholysis and deposition of IgG in intercellular spaces. In conclusion, the PV-sIVIG preparation is more effective than native IVIG in inhibiting anti-desmoglein-induced pemphigus vulgaris in mice and might serve as a future therapy in patients with the clinical disease.

Intravenous immunoglobulin G: trends in production methods, quality control and quality assurance.

Intravenous immunoglobulin G (IVIG) is now the leading product obtained by fractionation of human plasma. It is the standard replacement therapy in primary and acquired humoral deficiency, and is also used for immunomodulatory therapy in various autoimmune disorders and transplantation. Over the last 30 years, the production processes of IVIG have evolved dramatically, gradually resulting in the development of intact IgG preparations safe to administer intravenously, with normal half-life and effector functions, prepared at increased yield, and exhibiting higher pathogen safety. This article reviews the developments that have led to modern IVIG preparations, the current methods used for plasma collection and fractionation, the safety measures implemented to minimize the risks of pathogen transmission and the major quality control tests that are available for product development and as part of mandatory batch release procedures.