Modern science for better quality control of medicinal products “Towards global harmonization of 3Rs in biologicals”: The report of an EPAA workshop

Integrating 3Rs approaches in WHO guidelines for the batch release testing of biologicals: Responses from a survey of National Control Laboratories and National Regulatory Authorities

The UK National Centre for the Replacement, Refinement, and Reduction of Animals in Research (NC3Rs) is reviewing World Health Organization (WHO) manuals, guidelines and recommendations for vaccines and biotherapeutics to identify the extent to which animal-based testing methods are described. The aim is to recommend where updates to these documents can lead to an increased and more harmonised adoption of 3Rs principles (i.e. Replacement, Reduction and Refinement of animal tests) in the quality control and batch release testing requirements for vaccines and biotherapeutics. Improved adoption of 3Rs principles and non-animal testing strategies will help to reduce the delays and costs associated with product release testing. Developing recommendations that are widely applicable by both the manufacturers and national regulatory authorities for vaccines and biological therapeutics globally requires a detailed understanding of how different organisations view the opportunities and barriers to better integration of the 3Rs. To facilitate this, we developed and distributed a survey aimed at individuals who work for national regulatory authorities (NRAs) and/or national control laboratories (NCLs). In this paper, we present the key findings from this survey and how these will help inform the recommendations for wider integration of 3Rs approaches by WHO in their guidance documents applicable to the quality control and batch release testing of vaccines and biotherapeutics.

The consistency approach for the substitution of in vivo testing for the quality control of established vaccines: practical considerations and progressive vision

The aim of this letter is to share the discussions and proposals made by the VAC2VAC consortium on how to support the deployment of the "Consistency Approach" for quality control of established vaccines and thus facilitate the substitution of in vivo testing. This work answers specific questions about " what does a control strategy according to the consistency testing look like" and " how to submit a control strategy defined according to the consistency testing". Some topics were answered in a very straightforward manner. This was the case when the deployment of the consistency approach and the corresponding changes in vaccines control strategy was supported by the generic application of procedures already described in regulatory guidelines/requirements and related to the establishment or change in the control strategy of vaccines. The application of other procedures required more specific attention and some were deeply debated before reaching a proposal. The key outcomes of this work are that robust science must be used to develop a substitution strategy and generate supportive data packages. And this good science can best occur with good scientific collaboration between the different parties involved. Therefore, early interaction between manufacturers and competent authorities before and during dossier submission is critical to success. The consistency approach, when approved and in place, will ensure vaccine products of assured quality reach the patient in a more efficient manner than when relying on in vivo testing. Adapting the mindset was one of the major hurdles to a progressive vision but there is now consensus between manufacturers and competent authorities to foster the elimination of in vivo testing for routine vaccine release testing.

Integrating 3Rs approaches in WHO guidelines for the batch release testing of biologicals: Responses from a survey of vaccines and biological therapeutics manufacturers

The UK National Centre for the Replacement, Refinement, and Reduction of Animals in Research (NC3Rs) has been tasked by the World Health Organization (WHO) to review the extent to which animal-based testing methods are described in their manuals, guidelines and recommendations for vaccines and biotherapeutics. The aim is to identify and recommend where updates to these documents can lead to an increased and more harmonised adoption of 3Rs principles (i.e. Replacement, Reduction and Refinement of animal tests) in the quality control and batch release testing requirements for vaccines and biotherapeutics. Developing recommendations that are widely applicable by both the manufacturers and national regulatory authorities for vaccines and biologicals globally requires a detailed understanding of how different organisations view the opportunities and barriers to better integration of the 3Rs. To facilitate this, we developed and distributed a survey aimed at vaccine and biotherapeutics manufacturers in July 2021. In this paper, we present the key findings from this survey and how these will help inform the recommendations for wider integration of 3Rs approaches by WHO in their guidance documents applicable to the quality control and batch testing of vaccines and biotherapeutics.

Accelerating Global Deletion of the Abnormal Toxicity Test for vaccines and biologicals. Planning common next steps. A workshop Report

This online workshop Accelerating Global Deletion of the Abnormal Toxicity Test for vaccines and biologicals. Planning common next steps was organized on October 14th, 2021, by the Animal Free Safety Assessment Collaboration (AFSA), the Humane Society International (HSI), the European Federation of Pharmaceutical Industries and Associations (EFPIA), in collaboration with the International Alliance of Biological Standardization (IABS). The workshop saw a participation of over a hundred representatives from international organizations, pharmaceutical industries and associations, and regulatory authorities of 28 countries. Participants reported on country- and region-specific regulatory requirements and, where present, on the perspectives on the waiving and elimination of the Abnormal Toxicity Test. With AFSA, HSI, EFPIA and IABS representatives as facilitators, the participants also discussed specific country/global actions to further secure the deletion of ATT from all regulatory requirements worldwide.

Integrating 3Rs approaches in WHO guidelines for the batch release testing of biologicals

Animal testing has long been integral to the development of biologicals, including vaccines. The use of animals can provide important information on potential toxicity, insights into their mechanism of action, pharmacokinetics and dynamics, physiologic distribution, and potency. However, the use of these same methods is often adopted into the post-licensure phase of the product life cycle for the monitoring of product qualities, such as potency or safety, as part of their routine batch release. The UK National Centre for the Replacement, Refinement, and Reduction of Animals in Research (NC3Rs) and the World Health Organization (WHO) are collaborating on a project to review animal-based testing methods described in WHO manuals, guidelines and recommendations for biologicals to identify where updates can lead to a more harmonised adoption of 3Rs principles (i.e. Replacement, Reduction, and Refinement of animal tests) in batch release testing requirements. An international working group consisting of more than 30 representatives from pharmaceutical and biotechnology companies, national control laboratories and regulatory bodies is performing this review. This project aims to address concerns about inconsistencies in the guidance for the scientifically justified use of animal methods required for the post-licensure quality control and batch release testing of biologicals, and the near absence of recommendations for the application of 3Rs principles within the relevant guidelines. Improved adoption of 3Rs principles and non-animal testing strategies will help to reduce the delays and costs associated with product release testing and help support faster access to products by the global communities who need them most urgently.

Determining the Specific Activity of Anti-Rabies Sera and Immunoglobulin Using Atomic Force Microscopy of Cell Cultures

BACKGROUND

Mouse neutralization test is widely used to determine the level of anti-rabies antibodies, but it is labor-intensive and time consuming. Alternative methods for determining the neutralizing activity of anti-rabies sera and immunoglobulin in cell cultures are also known. Methods such as FAVN and RFFIT involve the use of fluorescent diagnostics. Determination of Cytopathic Effect (CPE) is often complicated due to features of rabies virus replication in cells. Atomic Force Microscopy (AFM) is able to detect the interaction of the virus with the cell at an early stage. Therefore, in this study, a method has been developed for determining the specific activity of anti-rabies sera and immunoglobulin using AFM of cell cultures.

METHODS

The method is based on the preliminary interaction of rabies virus with samples of rabies sera or immunoglobulin drug, adding the specified reaction mixture to cell culture (Vero or BHK-21), and then measuring the surface roughness of the cells using AFM. AFM was carried out in the intermittent contact mode by the mismatch method in the semi-contact mode. The results were compared with the values obtained in the mouse neutralization test. The consistency of the results obtained by both methods was evaluated by Bland-Altman method.

RESULTS

The increment in the surface roughness of the cells is a consequence of the damaging effect of the virus, which is weakened as a result of its neutralization by rabies antibodies. A dilution allowing 50% suppression of the increase in the surface roughness of cells was selected as the titer of rabies sera or immunoglobulin. In this case, the recommended range for determining the antibody titer is from 1:100 to 1:3000.

CONCLUSION

For the first time, a new methodological approach in virology and pharmaceutical research is presented in this study. The use of the proposed methodological technique will reduce the time from 21 to 2 days to obtain results in comparison with the mouse neutralization test; also, fewer laboratory animals are required in this approach which is in agreement with 3 R Principle.

Animal testing for vaccines. Implementing replacement, reduction and refinement: challenges and priorities

Transition to in vitro alternative methods from in vivo in vaccine release testing and characterization, the implementation of the consistency approach, and a drive towards international harmonization of regulatory requirements are most pressing needs in the field of vaccines. It is critical for global vaccine community to work together to secure effective progress towards animal welfare and to ensure that vaccines of ever higher quality can reach the populations in need in the shortest possible timeframe. Advancements in the field, case studies, and experiences from Low and Middle Income Countries (LMIC) were the topics discussed by an international gathering of experts during a recent conference titled "Animal Testing for Vaccines - Implementing Replacement, Reduction and Refinement: Challenges and Priorities". This conference was organized by the International Alliance for Biological Standardization (IABS), and held in Bangkok, Thailand on December 3 and 4 2019. Participants comprised stakeholders from many parts of the world, including vaccine developers, manufacturers and regulators from Asia, Europe, North America, Australia and New Zealand. In interactive workshops and vibrant panel discussions, the attendees worked together to identify the remaining barriers to validation, acceptance and implementation of alternative methods, and how harmonization could be promoted, especially for LMICs.

Nitric Oxide Production and Fc Receptor-Mediated Phagocytosis as Functional Readouts of Macrophage Activity upon Stimulation with Inactivated Poultry Vaccines In Vitro

Vaccine batches must pass routine quality control to confirm that their ability to induce protection against disease is consistent with batches of proven efficacy from development studies. For poultry vaccines, these tests are often performed in laboratory chickens by vaccination-challenge trials or serological assays. The aim of this study was to investigate innate immune responses against inactivated poultry vaccines and identify candidate immune parameters for in vitro quality tests as alternatives for animal-based quality tests. For this purpose, we set up assays to measure nitric oxide production and phagocytosis by the macrophage-like cell line HD11, upon stimulation with inactivated poultry vaccines for infectious bronchitis virus (IBV), Newcastle disease virus (NDV), and egg drop syndrome virus (EDSV). In both assays, macrophages became activated after stimulation with various toll-like receptor agonists. Inactivated poultry vaccines stimulated HD11 cells to produce nitric oxide due to the presence of mineral oil adjuvant. Moreover, inactivated poultry vaccines were found to enhance Fc receptor-mediated phagocytosis due to the presence of allantoic fluid in the vaccine antigen preparations. We showed that inactivated poultry vaccines stimulated nitric oxide production and Fc receptor-mediated phagocytosis by chicken macrophages. Similar to antigen quantification methods, the cell-based assays described here can be used for future assessment of vaccine batch-to-batch consistency. The ability of the assays to determine the immunopotentiating properties of inactivated poultry vaccines provides an additional step in the replacement of current in vivo batch-release quality tests.

Removal of the innocuity test from The International Pharmacopoeia and WHO recommendations for vaccines and biological products

The innocuity test was indicated as a quality control test to release pharmaceutical and biological products to the market. The test was intended to detect possible extraneous toxic contaminants derived from the manufacturing processes of the product. The test was included in WHO Recommendations and Guidelines for vaccines, biotherapeutics and blood products and in some monographs on antibiotics in The International Pharmacopoeia. Over the past years, the requirements in WHO Recommendations/Guidelines for conducting the test evolved such that it could be waived for routine release of product once consistency of production was established to the satisfaction of the NRA, or that the need for this test should be discussed and agreed with the NRA. However, some users of WHO written standards for biologicals (i.e., Recommendations, Guidelines) and WHO specifications for pharmaceuticals (i.e., The International Pharmacopoeia) requested that the innocuity test be deleted from WHO written standards based on its lack of specificity and scientific relevance. In response to that request, we studied the history of this test and its use by the member states of WHO, and the recommendations in WHO written standards. The outcomes of the study were reviewed by the relevant WHO Expert Committee on Biological Standardization and Expert Committee on Specifications for Pharmaceutical Products who then decided to discontinue this test in WHO Recommendations for vaccines and biologicals and to omit the test from The International Pharmacopoeia.

A novel electrophoretic immunoblot as antigen desorption and quantification method for alum-adjuvanted veterinary rabies vaccines

Rabies vaccines for domestic animals are adjuvanted with aluminum salts. A particular challenge for in-vitro batch potency tests with these products is the fact that the antigens are firmly adsorbed to the aluminum salt matrix and thus are not easily available for antigen quantification. In the current manuscript we describe a versatile technique to quantify antigens in aluminum adsorbed vaccine formulations. A combined electrophoretic desorption and blotting method is presented that transfers the antigens to a nitrocellulose membrane followed by an immunoblot quantification of the transferred rabies antigens. For the immunoblot a rabies G-protein specific, monoclonal antibody is used that by itself has neutralizing activity. This ensures that only relevant antigens are quantified. By comparing end products with non-adjuvanted in-process material it can be demonstrated that the antigens are quantitatively desorbed from the adjuvant matrix. Resuts of the new antigen quantification method were compared with the outcome of the serological batch potency test as described in the European Pharmacopoeia. It is demonstrated that the new antigen quantification method reveals relevant differences between experimental vaccine batches formulated with increasing antigen loads. This proves the broad detection range of the method. In general, the results show that this highly versatile technique can serve as an important component of a comprehensive consistency test strategy and may be applied in a modified form to any alum-adjuvanted vaccine.

Erysipelothrix Spp.: Past, Present, and Future Directions in Vaccine Research

Erysipelothrix spp. comprise a group of small Gram-positive bacteria that can infect a variety of hosts including mammals, fish, birds, reptiles and insects. Among the eight Erysipelothrix species that have been described to date, only Erysipelothrix rhusiopathiae plays a major role in farmed livestock where it is the causative agent of erysipelas. E. rhusiopathiae also has zoonotic potential and can cause erysipeloid in humans with a clear occupational link to meat and fish industries. While there are 28 known Erysipelothrix serovars, over 80% of identified isolates belong to serovars 1 or 2. Vaccines to protect pigs against E. rhusiopathiae first became available in 1883 as a response to an epizootic of swine erysipelas in southern France. The overall vaccine repertoire was notably enlarged between the 1940s and 1960s following major outbreaks of swine erysipelas in the Midwest USA and has changed little since. Traditionally, E. rhusiopathiae serovar 1a or 2 isolates were inactivated (bacterins) or attenuated and these types of vaccines are still used today on a global basis. E. rhusiopathiae vaccines are most commonly used in pigs, poultry, and sheep where the bacterium can cause considerable economic losses. In addition, erysipelas vaccination is also utilized in selected vulnerable susceptible populations, such as marine mammals in aquariums, which are commonly vaccinated at regular intervals. While commercially produced erysipelas vaccines appear to provide good protection against clinical disease, in recent years there has been an increase in perceived vaccine failures in farmed animals, especially in organic outdoor operations. Moreover, clinical erysipelas outbreaks have been reported in animal populations not previously considered at risk. This has raised concerns over a possible lack of vaccine protection across various production species. This review focuses on summarizing the history and the present status of E. rhusiopathiae vaccines, the current knowledge on protection including surface antigens, and also provides an outlook into future directions for vaccine development.

One science-driven approach for the regulatory implementation of alternative methods: A multi-sector perspective

EU regulations call for the use of alternative methods to animal testing. During the last decade, an increasing number of alternative approaches have been formally adopted. In parallel, new 3Rs-relevant technologies and mechanistic approaches have increasingly contributed to hazard identification and risk assessment evolution. In this changing landscape, an EPAA meeting reviewed the challenges that different industry sectors face in the implementation of alternative methods following a science-driven approach. Although clear progress was acknowledged in animal testing reduction and refinement thanks to an integration of scientifically robust approaches, the following challenges were identified: i) further characterization of toxicity pathways; ii) development of assays covering current scientific gaps, iii) better characterization of links between in vitro readouts and outcome in the target species; iv) better definition of alternative method applicability domains, and v) appropriate implementation of the available approaches. For areas having regulatory adopted alternative methods (e.g., vaccine batch testing), harmonised acceptance across geographical regions was considered critical for broader application. Overall, the main constraints to the application of non-animal alternatives are the still existing gaps in scientific knowledge and technological limitations. The science-driven identification of most appropriate methods is key for furthering a multi-sectorial decrease in animal testing.