Pathogen safety of intravenous Rh immunoglobulin liquid and other immune globulin products: enhanced nanofiltration and manufacturing process overview

Serial virus filtration: A case study evaluating the product-dependent impact of control strategies on process efficiency

The production of biopharmaceutical products carries an inherent risk of contamination by adventitious viruses. Historically, these manufacturing processes have incorporated a dedicated virus filtration step to ensure product safety. However, challenging process conditions can lead to passage of small viruses to the permeate pool and an overall decrease in the desired virus logarithmic reduction value (LRV) for the process. The implementation of serial virus filtration has improved the robustness of such processes, albeit concerns about increased operating times and process complexity have limited its implementation. This work focused on optimizing a serial filtration process and identifying process control strategies to provide maximum efficiency while ensuring proper controls for process complexity. Constant TMP was identified as the optimal control strategy, which combined with the optimal filter ratio, resulted in a robust and faster virus filtration process. To demonstrate this hypothesis, data with two filters connected in series (1:1 filter ratio) are presented for a representative non-fouling molecule. Similarly, for a fouling product, the optimal setup was a combination of a filter connected in series to two filters operated in parallel (2:1 filter ratio). The optimized filter ratios bring cost- and time-savings benefits to the virus filtration step, thereby offering improved productivity. The results of risk and cost analyses performed as part of this study combined with the control strategy, offer companies a toolbox of strategies to accommodate products with different filterability profiles in their downstream processes. This work demonstrates that the safety advantages of performing filters in series can be achieved with minimal increases in time, cost, and risk.

Therapeutic Plasma Exchange in Certain Immune-Mediated Neurological Disorders: Focus on a Novel Nanomembrane-Based Technology

Therapeutic plasma exchange (TPE) is an efficient extracorporeal blood purification technique to remove circulating autoantibodies and other pathogenic substances. Its mechanism of action in immune-mediated neurological disorders includes immediate intravascular reduction of autoantibody concentration, pulsed induction of antibody redistribution, and subsequent immunomodulatory changes. Conventional TPE with 1 to 1.5 total plasma volume (TPV) exchange is a well-established treatment in Guillain-Barre Syndrome, Chronic Inflammatory Demyelinating Polyradiculoneuropathy, Neuromyelitis Optica Spectrum Disorder, Myasthenia Gravis and Multiple Sclerosis. There is insufficient evidence for the efficacy of so-called low volume plasma exchange (LVPE) (<1 TPV exchange) implemented either by the conventional or by a novel nanomembrane-based TPE in these neurological conditions, including their impact on conductivity and neuroregenerative recovery. In this narrative review, we focus on the role of nanomembrane-based technology as an alternative LVPE treatment option in these neurological conditions. Nanomembrane-based technology is a promising type of TPE, which seems to share the basic advantages of the conventional one, but probably with fewer adverse effects. It could play a valuable role in patient management by ameliorating neurological symptoms, improving disability, and reducing oxidative stress in a cost-effective way. Further research is needed to identify which patients benefit most from this novel TPE technology.

Virus filtration: A Review of Current and Future Practices in Bioprocessing

For drug products manufactured in mammalian cells, safety assurance practices are needed during production to assure that the final medicinal product is safe from the potential risk of viral contamination. Virus filters provide viral retention for a range of viruses through robust, largely size-based retention mechanism. Therefore, a virus filtration step is commonly utilized in a well-designed recombinant therapeutic protein purification process and is a key component in an overall strategy to minimize the risks of adventitious and endogenous viral particles during the manufacturing of biotechnology products. This review summarizes the history of virus filtration, currently available virus filters and prefilters, and virus filtration integrity test methods and study models. There is also discussion of current understanding and gaps with an eye toward future trends and emerging filtration technologies. This article is protected by copyright. All rights reserved.

Pathology Consultation on Patients With a Large Rh Immune Globulin Dose Requirement

OBJECTIVES

To review the differential diagnosis and laboratory issues for women with a large calculated dose of Rh immune globulin (RhIG).

METHODS

A case-based approach is used to review the differential diagnosis of patients with a large calculated dose of RhIG, RhIG dosing for women with baseline elevations in hemoglobin F, the formulations of RhIG, and issues for the transfusion medicine service with the release of large doses of RhIG.

RESULTS

A large fetomaternal bleed after delivery requiring multiple doses of RhIG is rare. Such patients may require intravenous RhIG to avoid multiple injections. Patients with a large percentage of circulating fetal RBCs should be evaluated for a disorder of hemoglobin synthesis and, if present, should have quantification of the circulating fetal RBCs by flow cytometry.

CONCLUSIONS

Accurate laboratory evaluation of women with large fetomaternal bleeds is essential for appropriate RhIG administration.

Virus safety of plasma products using 20 nm instead of 15 nm filtration as virus removing step

During the manufacture of human plasma derivatives, a series of complementary measures are undertaken to prevent transmission of blood-borne viruses. Virus filtration using 15 nm (Planova15N) filters has successfully been implemented in manufacturing processes for various plasma derivatives primarily because virus filtration is a technique, mild for proteins, that can effectively remove even small non-lipid-enveloped viruses, such as HAV and parvovirus B19. However, the use of 15 nm filters has limitations with regard to protein capacity of the filters and the process flow, resulting in an expensive manufacturing step. Therefore, studies were performed to test whether the use of 20 nm (Planova20N) filters, having different characteristics compared to 15 nm filters, can be an alternative for the use of 15 nm filters. It is shown that 20 nm filtration can be an alternative for 15 nm filtration. However, the virus removal capacity of the 20 nm filters depends on the plasma product that is filtered. Therefore, an optimisation study must be performed with regard to process parameters such as pressure, pH and protein concentration for each plasma product. In this study, using optimised conditions, the virus removal capacity of 20 nm filters appears to be comparable or even better when compared to that of 15 nm filters.

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.

Viral safety characteristics of Flebogamma DIF, a new pasteurized, solvent-detergent treated and Planova 20 nm nanofiltered intravenous immunoglobulin

A new human liquid intravenous immunoglobulin product, Flebogamma DIF, has been developed. This IgG is purified from human plasma by cold ethanol fractionation, PEG precipitation and ion exchange chromatography. The manufacturing process includes three different specific pathogen clearance (inactivation/removal) steps: pasteurization, solvent/detergent treatment and Planova nanofiltration with a pore size of 20 nm. This study evaluates the pathogen clearance capacity of seven steps in the production process for a wide range of viruses through spiking experiments: the three specific steps mentioned above and also four more production steps. Infectivity of samples was measured using a Tissue Culture Infectious Dose assay (log(10) TCID(50)) or Plaque Forming Units assay (log(10) PFU). Validation studies demonstrated that each specific step cleared more than 4 log(10) for all viruses assayed. An overall viral clearance between > or =13.33 log(10) and > or =25.21 log(10), was achieved depending on the virus and the number of steps studied for each virus. It can be concluded that Flebogamma DIF has a very high viral safety profile.

Efficacy, pharmacokinetics, safety, and tolerability of Flebogamma 10% DIF, a high-purity human intravenous immunoglobulin, in primary immunodeficiency

BACKGROUND

Flebogamma 10% DIF represents an evolution of intravenous immune globulin from the previous 5% product to be administered at higher rates and with smaller infusion volumes. Pathogen safety is enhanced by the combination of multiple methods with different mechanisms of action.

OBJECTIVE

The objective of this study as to evaluate the efficacy, pharmacokinetics, and safety of Flebogamma 10% DIF for immunoglobulin replacement therapy in primary immunodeficiency diseases (PIDD).

METHODS

Flebogamma 10% DIF was administered to 46 subjects with well-defined PIDD at a dose of 300-600 mg/kg every 21-28 days for 12 months.

RESULTS

Serious bacterial infection rate was 0.025/subject/year. Half-life in serum of the administered IgG was approximately 35 days. No serious treatment-related adverse event (AE) occurred in any patient. Most of the potentially treatment-related AEs occurred during the infusion, accounting for 20% of the 601 infusions administered.

CONCLUSIONS

Flebogamma 10% DIF is efficacious and safe, has adequate pharmacokinetic properties, and is well-tolerated for the treatment of PIDD.