Capacity of the manufacturing process of Flebogamma® DIF, a new human high purity intravenous immunoglobulin, to remove a TSE model-agent

Integration of Planova filters in manufacturing processes of biologicals improve the virus safety effectively: A review of publicly available data

The capacity to remove viruses by Planova filters produced by Asahi Kasei, primarily by small virus-retentive filters, were compiled from data in peer-reviewed publications and, partly, publicly available data from presentations at conferences (Planova workshops). Data from more than 100 publications and presentations at conferences covering Planova filters were assessed. The data were grouped according to the different virus filters regarding mean pore sizes and viruses of different sizes for plasma and cell culture derived products. Planova 15N and 20N filters removed parvoviruses below the limit of detection of viruses in the filtrate in approx. 50% of all studies and mean LRFs (log reduction factors) for viruses detected in the filtrate were above 4, demonstrating effective parvovirus reduction. Parvovirus removal capacity increased for Planova BioEX filters as well as for 2 Planova 20N in series. Large viruses as retroviruses (e.g., HIV and MuLV), herpesviruses, flaviviruses and togaviruses were removed effectively by Planova 15N, 20N and BioEX filters and also by Planova 35N filters. Flow interruption, transmembrane pressure, volume and protein concentration per filter area had had no substantial impact on virus removal capacity at manufacturing specification. In conclusion, the incorporation of Planova filters in manufacturing processes of biologicals remove, depending on the filter pore size, small and large viruses from the feed stream reliably. This virus reduction step with an orthogonal mechanism integrated in the manufacturing processes of biologicals, based primarily on size exclusion of viruses, improves the virus safety of these biopharmaceutical products considerably.

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.

Pathogen Safety of a New Intravenous Immune Globulin 10% Liquid

BACKGROUND

The manufacturing process of a new intravenous immune globulin (IVIG) 10% liquid product incorporates two dedicated pathogen safety steps: solvent/detergent (S/D) treatment and nanofiltration (20 nm). Ion-exchange chromatography (IEC) during protein purification also contributes to pathogen safety. The ability of these three process steps to inactivate/remove viruses and prions was evaluated.

OBJECTIVES

The objective of this study was to evaluate the virus and prion safety of the new IVIG 10% liquid.

METHODS

Bovine viral diarrhea virus (BVDV), human immunodeficiency virus type 1 (HIV-1), mouse encephalomyelitis virus (MEV), porcine parvovirus (PPV), and pseudorabies virus (PRV) were used as models for common human viruses. The hamster-adapted scrapie strain 263K (HAS 263K) was used for transmissible spongiform encephalopathies. Virus clearance capacity and robustness of virus reduction were determined for the three steps. Abnormal prion protein (PrP^Sc) removal and infectivity of the samples was determined.

RESULTS

S/D treatment and nanofiltration inactivated/removed enveloped viruses to below detection limits. IEC supplements viral safety and nanofiltration was highly effective in removing non-enveloped viruses and HAS 263K. Overall virus reduction factors were: ≥9.4 log₁₀ (HIV-1), ≥13.2 log₁₀ (PRV), ≥8.2 log₁₀ (BVDV), ≥11.7 log₁₀ (MEV), ≥11.6 log₁₀ (PPV), and ≥10.4 log₁₀ (HAS 263K).

CONCLUSION

Two dedicated and one supplementing steps in the manufacturing process of the new IVIG 10% liquid provide a high margin of pathogen safety.

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.

Safety and efficacy of a 10% intravenous immunoglobulin preparation in patients with immune thrombocytopenic purpura: results of two international, multicenter studies

AIM

To assess safety and efficacy of a 10% intravenous immunoglobulin in patients with primary immune thrombocytopenic purpura (ITP).

PATIENTS & METHODS

ITP patients in two multicenter studies (Trials A/B) were treated with 2 g/kg Flebogamma^® 10% DIF (over 2-5 days) and were followed up to 1-3 months.

RESULTS

18 patients in Trial A and 58 in Trial B were enrolled (12 children in Trial B). The response rate (platelet count ≥50 × 10⁹/l) was 72.2% (Trial A) and 76.1/100% (adults/children; Trial B). Most patients improved bleedings (83.3% Trial A; 88.9% Trial B). Potential treatment-related adverse events were reported by 38.9% (Trial A) and 30.4/83.3% (adults/children; Trial B) of patients. All serious adverse events (five patients) resolved without sequelae.

CONCLUSION

Flebogamma 10% DIF was effective and safe in patients with primary ITP.

The safety of treatments for angioedema with hereditary C1 inhibitor deficiency

INTRODUCTION

Angioedema is a localized and self-limiting edema of the subcutaneous and submucosal tissue. Hereditary angioedema with C1 inhibitor deficiency (C1-INH-HAE) is the best characterized form of hereditary angioedema. In C1-INH-HAE, the reduced plasma levels of C1-INH cause instability of the contact system with release of bradykinin, the key mediator of angioedema. C1-INH-HAE is characterized by recurrent skin swelling, abdominal pain, and potentially life-threatening upper airways obstruction. Knowledge of the molecular mechanisms leading from C1-INH deficiency to angioedema allowed the development of several therapies.

AREAS COVERED

The aim of this review article is to discuss the safety of currently available treatments of C1-INH-HAE. The authors give an insight on the mechanism of action and safety profile of drugs for treatment of acute attacks and for short- and long-term prophylaxis. Evidence from systematic reviews, clinical trials, retrospective studies, and case reports is summarized in this review.

EXPERT OPINION

C1-INH-HAE is a disabling, life-threatening condition that lasts life-long. Different therapeutic approaches with different drugs provide significant benefit to patients. Safety profiles of these therapies are critical for optimal therapeutic decision and need to be known by C1-INH-HAE treating physicians for appropriate risk/benefit evaluation.

Characterization of Thrombate III®, a pasteurized and nanofiltered therapeutic human antithrombin concentrate

Thrombate III(®) is a highly purified antithrombin concentrate that has been used by clinicians worldwide for more than two decades for the treatment of hereditary antithrombin deficiency. The manufacturing process is based on heparin-affinity chromatography and pasteurization. To modernize the process and to further enhance the pathogen safety profile of the final product, despite the absence of infectious disease transmission, a nanofiltration step was added. The biochemical characterization and pathogen safety evaluation of Thrombate III(®) manufactured using the modernized process are presented. Bioanalytical data demonstrate that the incorporation of nanofiltration has no impact on the antithrombin content, potency, and purity of the product. Scaledown models of the manufacturing process were used to assess virus and prion clearance under manufacturing setpoint conditions. Additionally, robustness of virus clearance was evaluated at or slightly outside the manufacturing operating limits. The results demonstrate that pasteurization inactivated both enveloped and non-enveloped viruses. The addition of nanofiltration substantially increased clearance capacities for both enveloped and non-enveloped viruses by approximately 4-6 log10. In addition, the process achieves 6.0 log10 ID50 prion infectivity clearance. Thus, the introduction of nanofiltration increased the pathogen safety margin of the manufacturing process without impacting the key biochemical characteristics of the product.

Protein sieving characteristics of sub-20-nm pore size filters at varying ionic strength during nanofiltration of Coagulation Factor IX

Nanofiltration assures that protein therapeutics are free of adventitious agents such as viruses. Nanofilter pores must allow passage of protein drugs but be small enough to retain viruses. Five nanofilters have been evaluated to identify those that can be used interchangeably to yield a high purity Coagulation Factor IX product. When product preparations prior to nanofiltration were analyzed using electrophoresis, Western blot, liquid chromatography - tandem mass spectrometry and size exclusion HPLC, factor IX, inter - α - trypsin inhibitor and C4b binding protein (C4BP) were observed. C4BP was removed from product by all five nanofilters when nanofiltration was performed at physiological ionic strength. However, at high ionic strength, C4BP was removed by only two nanofilters. HPLC indicated that the Stokes radius of C4BP was larger at low ionic strength than at high ionic strength. The results suggest that C4BP exists in an open conformation at physiological ionic strength and is removed by nanofiltration whereas, at high ionic strength, the protein collapses to an extent that allows passage through some nanofilters. Manufacturers should be aware that protein contaminants in other nanofiltered protein drugs could behave similarly and conditions of nanofiltration must be evaluated to ensure consistent product purity.

Pathogen safety of human C1 esterase inhibitor concentrate

BACKGROUND

Human plasma-derived products--such as C1 esterase inhibitor (C1-INH) concentrate, used to treat hereditary angioedema--carry with them the risk of transmitting blood-borne viruses and, theoretically, prion proteins. To minimize this risk, three complementary approaches are implemented: selection and testing of plasma donations for the absence of pathogenic blood-borne viruses, similarly testing and releasing the plasma pool for fractionation, and ensuring that the manufacturing process includes validated steps for pathogen inactivation and removal.

STUDY DESIGN AND METHODS

This article describes the selection of plasma for the production of C1-INH and the studies used to confirm the pathogen reduction capacity of the manufacturing process: three independent virus reduction steps--pasteurization, hydrophobic interaction chromatography (HIC), and virus filtration--and two prion reduction steps. Samples of product intermediates from the manufacturing steps were spiked with a panel of enveloped and nonenveloped viruses and two prion preparations and subjected to a valid scaled-down version of the respective manufacturing steps resulting in the quantification of the pathogen reduction factors.

RESULTS

Validation studies demonstrated overall virus reduction factors for all viruses of more than 15 log, considerably exceeding the potential amount of virus present in a plasma pool for fractionation. Prion proteins were also efficiently removed by the manufacturing process, as currently determined in evaluating the prion removal capacity of the ammonium sulfate precipitation and HIC steps.

CONCLUSION

The pathogen reduction capacity demonstrated here indicates that the manufacturing process of the C1-INH Berinert is highly effective for reducing enveloped and nonenveloped viruses and prion proteins.

Comparison of nanofiltration efficacy in reducing infectivity of centrifuged versus ultracentrifuged 263K scrapie-infected brain homogenates in "spiked" albumin solutions

BACKGROUND

The safety of plasma-derived products is of concern for possible transmission of variant Creutzfeldt-Jakob disease. The absence of validated screening tests requires the use of procedures to remove or inactivate prions during the manufacture of plasma-derived products to minimize the risk of transmission. These procedures need proper validation studies based on spiking human plasma or intermediate fractions of plasma fractionation with prions in a form as close as possible to that present in blood.

STUDY DESIGN AND METHODS

Human albumin was spiked with low-speed or high-speed supernatants of 263K scrapie-infected hamster brain homogenates. Spiked albumin was then passed through a cascade of filters from 100 nm down to 20 to 15 nm. Residual infectivity was measured by bioassay.

RESULTS

The overall removal of infectivity spiked into albumin through serial nanofiltration steps was 4 to 5 logs using low-speed supernatant and 2 to 3 logs with high-speed supernatant.

CONCLUSION

These findings confirm the utility of nanofiltration in removing infectivity from plasma (or other products) spiked with scrapie brain homogenate supernatants. However, efficiency is diminished using supernatants that have been ultracentrifuged to reduce aggregated forms of the infectious agent. Thus, filtration removal data based on experiments using "standard" low-speed centrifugation supernatants might overestimate the amount of prion removal in plasma or urine-derived therapeutic products.