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Abstract: In the context of increased demand of blood components, it is highly desirable to ensure development and implementation of established standards for ethical, organisational and regulatory fields in order to guarantee the sufficiency, quality and safety of blood components and their derivatives as well as the protection of donors and recipients. In Europe, the contributions of the European public institutions is fundamental for the achievement of these goals and for the harmonisation of practices inherent to transfusional medicine activities. The Council of Europe with its 47 member states constitutes the ideal platform to tackle these themes: for half a century, its public health and bioethics experts have contributed to the elaboration of conventions and recommendations which serve as a model to elaboration of national or European regulations relevant to this field. [Copyright &y& Elsevier]

To comply with European Pharmacopoeia (Ph. Eur.) monograph Human albumin solution (0255), albumin solutions have to be tested for molecular-size distribution by size-exclusion chromatography (SEC). However, differences in interpretation of the test results continue to be observed among albumin manufacturers in Europe. A collaborative study was run by the European Directorate for the Quality of Medicines & HealthCare (EDQM), under the aegis of the Biological Standardisation Programme (BSP), to support the revision of Ph. Eur. monograph 0255 and to establish a Biological Reference Preparation (BRP) for use in the molecular-size distribution test. In 2019, Ph. Eur. Expert Group 6B proposed to include an analytical improvement of the SEC procedure in the monograph, which was then submitted for public enquiry. This publication describes the evaluation of three candidate BRPs to serve as a tool for both the system suitability test (SST) and albumin monomer and dimer peak identification according to the proposed revised methodology. Three Official Medicines Control Laboratories (OMCLs) involved in the official batch release of human albumin solution took part in the study. Based on the study results, the candidate BRPs were found suitable for purpose and were adopted by the Ph. Eur. Commission as Ph. Eur. Human albumin (molecular size) BRP batches 1, 2 and 3 concomitantly with the revised monograph Human albumin solution (0255) in November 2020., (© Council of Europe, 2021.)

Two preparations of the chimeric anti-Tumour Necrosis Factor (TNF) monoclonal antibody Infliximab were formulated and lyophilised at the National Institute for Biological Standards & Control (NIBSC) prior to evaluation in a collaborative study for their suitability to serve as a World Health Organization (WHO) International Standard (IS)/European Pharmacopoeia (Ph. Eur.) Biological Reference Preparation (BRP) for the potency assay of Infliximab. Twenty-six laboratories tested the preparations using different in vitro cell-based bioassays (TNF-α neutralisation, antibody-dependent cellular cytotoxicity and complement-dependent cytotoxicity) and binding assays. Amongst them, 19 laboratories performed cell-based bioassays. The results of this study indicated that the candidate preparation coded 16/170 was suitable to serve as an International Standard for Infliximab based on the data obtained for biological activity. This candidate standard was established in 2017 as the first International Standard for Infliximab with an assigned potency for TNF neutralisation activity of 500 IU per ampoule. In the same study, the suitability of preparation 16/170 of Infliximab to serve as the European Pharmacopoeia (Ph. Eur.) Biological Reference Preparation (BRP) for the Infliximab potency assay as described in the Ph. Eur. monograph on Infliximab concentrated solution (2928) was also evaluated. The corresponding analysis, based on the measurement of the inhibitory action of anti-human TNF (Infliximab) on the cytotoxic activity of TNF-alpha, was performed using data from a subset of 9 laboratories using the TNF-alpha-sensitive fibrosarcoma cell line WEHI-164. The results obtained were compared to those obtained from different cell-based neutralisation assays that were used by other laboratories in the context of establishing the 1st World Health Organization (WHO) International Standard (IS) for Infliximab. Based on the analyses, preparation 16/170 was adopted by the Ph. Eur. Commission in June 2018 as Infliximab BRP batch 1 with an assigned potency of 500 IU per ampoule., (© Council of Europe 2020.)

Equine influenza (EI) is an important respiratory disease of horses, with welfare and economic consequences. Vaccination remains one of the most efficient prevention methods available. Equine influenza virus (EIV) is constantly evolving and consequently EI vaccines need to be updated on a regular basis. In 2010, the World Organisation for Animal Health (OIE) Expert Surveillance Panel (ESP) on EI provided a new recommendation for EI vaccine strain composition, including the incorporation of representative EIV strains of both Florida Clade 1 and Clade 2 sub-lineages (FC1 and FC2, respectively). In this context, the European Pharmacopoeia (Ph. Eur.) - OIE reference panel for EI had to be complemented by an antiserum raised in horses against the FC2 representative EIV strain A/eq/Richmond/1/07. An international collaborative study was organised and managed by the European Directorate for the Quality of Medicines and HealthCare (EDQM) within the framework of its Biological Standardisation Programme (BSP). The study aimed at evaluating a new candidate reference for use as a common OIE International Standard/Ph. Eur. Biological Reference Preparation (BRP) horse antiserum to FC2 EIV A/equine/Richmond/1/07. The standard was to be established using the SRH and HI tests for subsequent use in immunogenicity, efficacy and batch potency assay of EI vaccines as a Ph. Eur. BRP (Ph. Eur. monograph 0249) and for use in clinical diagnostic tests as an OIE-approved International Standard Reagent (OIE chapter 3.5.7). The collaborative study confirmed the suitability of the candidate and an SRH titre was assigned. The candidate was adopted as a BRP by the Ph. Eur. Commission and approved by the OIE Biological Standards Commission as an International Standard Serum in November 2017 and February 2018, respectively., (© Council of Europe 2020.)

For acellular pertussis (aP) vaccines, the current European Pharmacopoeia (Ph. Eur.) monograph Pertussis vaccine (acellular, component, adsorbed) (1356) requires an immunogenicity assay in mice or guinea pigs to assess the potency of each lot of vaccine (Ph. Eur. general method 2.7.16. Assay of pertussis vaccine (acellular)). This biological assay, carried out on the final bulk of the vaccine lot, is based on the measurement of the specific antibody response to the 5 antigenic components (pertussis toxin (PT), Fimbrial haemagglutinin (FHA), pertactin (PRN) and Fimbriae 2 and 3 (FIM2/3)) that are present in the combined aP vaccines. In the mouse assay, serum antibody levels are measured by ELISA. The immunogenicity of a vaccine under test is estimated versus a homologous reference vaccine and a reference antiserum e.g. the first Ph. Eur. Biological Reference Preparation for Bordetella (B.) pertussis mouse anti-serum (BRP1), established in 1998, is used to normalise the titre of antibodies (expressed in ELISA Units (ELU)/mL). In anticipation of the depletion of BRP1 stocks, a project was launched in 2013 by the Biological Standardisation Programme (BSP) of the European Directorate for the Quality of Medicines & HealthCare (EDQM) in order to establish a new standardised reference serum. The project, referred to herein as BSP129, was conducted in 2 phases: 1) the production and characterisation of a mouse serum pool (using a multicomponent aP vaccine marketed in Canada similar to the vaccine used in the BRP1 production as immunogen) and of candidate BRP batches (cBRPs) and 2) an international collaborative study aimed at calibrating the cBRPs in terms of antibody levels against PT, FHA, PRN and FIM2/3. This article presents the design and results of the first phase of the collaborative study to establish the optimal conditions for immunisation and bleeding of mice in order to produce a large pool of hyper-immune serum against the 5 antigens. After the characterisation of this pool, cBRP pilot lots were manufactured by freeze-drying diluted solutions of the hyper-immune serum pool. The pilot lots were then characterised in two Official Medicines Control Laboratories (OMCLs) for their antibody contents against aP vaccine antigens using in-house ELISA (based on methods developed by 2 European vaccine manufacturers) and Multiplex Immunoassay (MIA) methods. The antibody titres recovered demonstrated that a dilution factor of 1/40 could be considered for the scaled-up manufacture of candidate reference preparations (cBRPs). Three batches (15 000 vials) of cBRP were manufactured and fully characterised. In light of the data obtained, and although titration results between the ELISA methods were sometimes discrepant, it was agreed that the establishment study (phase 2) could be launched. Real-time and accelerated stability studies were also included in the first study phase to document the stability of the cBRPs in freeze-dried form and after reconstitution and storage at -20°C±5°C. The results showed that the stability of the freeze-dried cBRPs at usual storage and shipment temperatures is acceptable and that reconstituted cBRP solutions are stable for 12 months at -20°C±5°C. It could therefore be recommended to freeze small aliquots of the 1 mL solution obtained by the reconstitution of one BRP vial in order to store them for use in separate assays. With the application of this strategy, the stocks of the BRP1 replacement batches should cover the needs of OMCLs and manufacturers for at least the next decade., (© Council of Europe 2020.)

Large numbers of mice are used in testing during the production of Clostridial vaccines. Previous work has indicated that cell line assays could replace mouse tests for certain aspects of this testing. Replacement assays have been developed for the testing of the toxins and toxoids of several clostridial species but none of these assays have been assessed in an international collaborative study. Under the common aegis of the European Partnership for Alternative Approaches to Animal Testing (EPAA) and of the European Directorate for the Quality of Medicines & HealthCare (EDQM), collaborative study BSP130 was initiated to evaluate Vero cell based alternative methods to the current mouse tests used to measure the toxicity of Clostridium septicum toxin (the minimum lethal dose (MLD) test), the freedom from toxicity of C. septicum toxoid (the MLD test) and the antigenicity of C. septicum toxoid (the total combining power (TCP) test). The principal aims of BSP130 were to determine the repeatability and reproducibility of the in vitro assays and to demonstrate concordance of the proposed in vitro and current in vivo TCP and MLD tests. 11 laboratories from 7 countries participated in the collaborative study and each tested 6 toxins and 6 toxoids. The participants' Vero cell lines were up to 1 000 times more sensitive than the mouse strains. The MLD assay in mice and on Vero cells generally ranked the toxins in a similar order in most of the laboratories. The TCP assay in mice and on Vero cells also generally ranked the toxoids in a similar order in most of the laboratories. The results demonstrate that the repeatability and reproducibility of the in vitro Vero cell based assays are no worse than that of the in vivo assays and that they are easily transferable to other laboratories. The concordance correlations between the in vivo and in vitro methods were for the MLD assays ρc=0.961 (log-transformed values) and ρc=0.921 (non-log-transformed values) and for the TCP assays ρc=0.968 (log-transformed values) and ρc=0.980 (non log-transformed values). These correlations are excellent showing that the Vero cell assays can be used as alternatives to the mouse tests for the assessment of C. septicum toxin MLD and toxoid TCP values. This study can be used by vaccine manufacturing companies as a guide for applying the same approach to other clostridial toxins and toxoids., (© Council of Europe 2020.)

This report summarizes recommendations relating to haemophilia therapy arising from discussions among experts from 36 European countries during the Kreuth III meeting in April 2013. To optimize the organization of haemophilia care nationally, it is recommended that a formal body be established in each country to include the relevant clinicians, national haemophilia patient organization, health ministry, paying authority and (if appropriate) regulatory authorities. The minimum factor VIII consumption level in a country should be 3 I.U. per capita. Decisions on whether to adopt a new product should not be based solely on cost. Prophylaxis for children with severe haemophilia is already recognized as the optimum therapy. Ongoing prophylaxis for individual adults should also be provided when required based on clinical decision making by the clinician in consultation with the patient. Children with inhibitors who have failed, or who are not suitable for, immune tolerance therapy should be offered prophylaxis with bypassing agents. Single factor concentrates should be used as therapy wherever possible in patients with rare bleeding disorders. Orphan drug designation for a factor concentrate should not be used to hinder the development, licencing and marketing of other products for the same condition which have demonstrably different protein modification or enhancement., (© 2014 John Wiley & Sons Ltd.)

Due to the diminished stocks of the 2(nd) batch of the European Pharmacopoeia (Ph. Eur.) Biological Reference Preparation (BRP) for human immunoglobulin for electrophoresis, in 2013, the European Directorate for the Quality of Medicines and HealthCare (EDQM) initiated an international collaborative study for the establishment of a replacement batch. The study was run under the aegis of the Biological Standardisation Programme (BSP). Seventeen laboratories participated in the collaborative study to verify the suitability of the candidate reference preparation according to the Ph. Eur. monographs 0338 and 0918 using the zone electrophoresis (ZE) method with either cellulose acetate and/or agarose as the testing medium. The candidate preparation was found suitable for the intended purpose and was subsequently adopted by the Ph. Eur. Commission as the human immunoglobulin for electrophoresis BRP batch 3 with an assigned range for immunoglobulin of 79.8 % to 86.4 % of the total protein content.

A joint project (coded BSP089) was run by the European Directorate for the Quality of Medicines & HealthCare (EDQM) of the Council of Europe, the National Institute for Biological Standards and Control (NIBSC) on behalf of the World Health Organization (WHO) and the Center for Biologics Evaluation and Research (CBER) of the U.S. Food and Drug Administration (FDA) to evaluate, in an international collaborative study, 3 lyophilised intravenous immunoglobulin (IVIG) preparations for their suitability to serve as Reference Preparations to standardise and control the highly variable haemagglutination testing for anti-A and anti-B in IVIG products. 23 laboratories tested candidate IVIG reference preparations consisting of a Positive control, a Negative control and a specifically formulated Limit test reference preparation to define the maximum (e.g., pharmacopoeial) limits of anti-A and anti-B haemagglutinins in IVIG products, where limits are applicable. Laboratories performed direct haemagglutination using papain-treated erythrocytes and/or indirect anti-globulin tests. For both methods, there was up to 16-fold variation in anti-A and anti-B titres, although there was good agreement over a 2-fold titre range for anti-A and anti-B between laboratories using the direct method for both the Positive control and Limit reference preparations. Comparative titration data for the Positive control and Limit reference preparations indicated that the use of a 'Limit' test reference preparation would facilitate identification of higher titre batches when the direct haemagglutination method is used. The Positive control, Negative control and Limit test preparations were adopted in November 2008 by the Commission of the European Pharmacopoeia (Ph. Eur.) as Biological Reference Preparations. The same preparations have been established as reference reagents by the WHO and the U.S FDA, including the maximal specifications defined by the Limit test preparation. This will facilitate global standardisation of haemagglutination tests for anti-A and anti-B, ensure that such tests are sufficiently sensitive and specific, and facilitate identification of batches that exceed maximum recommended levels of anti-A and anti-B antibodies.

The European Pharmacopoeia (Ph. Eur.) and the World Health Organisation (WHO) require the performance of extensive quality and safety control testing before the release on the market of vaccine products for human use. Safety testing with regard to residual pertussis toxin (PT) in acellular pertussis combination vaccines is performed through assessment of fatal sensitisation of mice to histamine challenge by the vaccine product under test. Currently, use of different in-house procedures and no requirement for the inclusion of a standard reference in each assay render comparisons of results obtained for identical vaccine batches between different control laboratories very difficult. At the initiative of the European Directorate for the Quality of Medicines and HealthCare (EDQM), an international collaborative study was organised for the standardization of the Histamine Sensitizing Test (HIST) in mice and the Chinese Hamster Ovary (CHO)-cell-based assay (performed at the bulk product level) for the residual toxicity testing of acellular pertussis vaccines or acellular pertussis-based combination vaccines. The study was run under the aegis of the Biological Standardisation Programme, jointly supported by the Council of Europe and the European Commission under the project code BSP076. Ten (10) laboratories participated in the study and were requested to perform 3 independent Histamine Sensitizing Tests in mice and to report results of the lethal end-point measurement as prescribed by the Ph. Eur. monographs. Some of them also reported data from an in-house validated CHO-cell-based assay. In addition, some of the laboratories reported concomitantly data obtained by measurement of the drop in temperature induced after the histamine challenge, a method currently under investigation to be added as an alternative end-point for the HIST in the Ph. Eur. monographs for acellular pertussis-based combination vaccines in order to alleviate animal suffering (in application of the 3Rs principle). Based on the results of the collaborative study, a potency of 7500 IU/vial (International Units per vial) was assigned to the current Ph. Eur. Biological Reference Preparation (BRP) for PT. The results of the study also show that 1) intra- and inter-laboratory variations can be improved by the use of a validated standard operating procedure; 2) inclusion in each assay of a standard reference sample, calibrated in IU, can increase comparability of results among laboratories and thus help to reduce repeat testing; 3) a correlation between mortality data and temperature data was observed although, due to the limited number of data sets and the lack of a common method for the temperature end-point, further investigation of this point is required; 4) the CHO-cell-based assay did not yield comparable results and further standardisation of the assay procedure may be investigated in a follow-up project.

An international collaborative study (coded BSP083) was performed under the aegis of the Biological Standardisation Programme supported by the Council of Europe and the European Commission, with the aim of replacing the in vivo challenge assays for potency determination of combined acellular pertussis (aP) vaccines by a refined procedure also allowing reduction of animal use. This study investigates whether the immunogenicity of aP vaccine components could be assayed in a guinea pig (gp) serology model, using the same vaccine immunising doses as for D and T components potency testing, instead of using separate animals as is currently done. The BSP83 project is a follow up of 3 former collaborative studies (coded BSP019, BSP034 and BSP035) on serological methods for the potency testing of tetanus (T) and diphtheria (D) vaccines for human use. The use of gp instead of mice serology has the advantage of providing a larger volume of good quality antiserum for the assay of several vaccine components in the same sample, hence providing the opportunity for animal sparing. The results of Phase I of the study demonstrated that gp serology may be a useful method for the immunogenicity assay of acellular pertussis vaccines. This was confirmed in Phase II of the study, using 7 different combined aP vaccines in an international collaborative study involving 17 laboratories from both public and private sectors. Clear dose-response relationships were observed for different vaccines by ELISA, for antibodies against aP antigens, i.e. pertussis toxin (PT), filamentous haemagglutinin (FHA), fimbrial agglutinogens-2/3 (Fim 2/3) and pertactin (PRN). Intra- and inter-laboratory variations of aP ELISA results were found to be within an acceptable range. For some combined vaccines, however, the range of vaccine dilutions for immunisation confirmed to be optimal for D and T potency testing may not provide optimal dose-response for all aP components. Method adjustments may thus be required and suitability should therefore be demonstrated for each vaccine combination and product prior to the application of this assay. The results of this study support the use of the gp serological method for the determination of the immunogenicity of aP vaccines. The application of the method for batch release testing of combined D, T and aP vaccines could significantly contribute to the implementation of the 3R principles through reduction of animal use and improved animal welfare, whilst reducing costs. As an outcome of this study, the Group of Experts No. 15 on Sera and Vaccines of the European Pharmacopoeia (Ph. Eur.) decided in February 2009 to include the gp serological assay as an example in the Ph. Eur. General chapter 2.7.16. on acellular pertussis vaccine assay.

Background and Objectives: The aim of the study was to evaluate, in an international collaboration, three lyophilized intravenous immunoglobulin (IVIG) preparations for their suitability to standardize and control haemagglutination testing for anti-A and anti-B in IVIG products., Materials and Methods: Twenty-three laboratories tested candidate IVIG reference reagents consisting of a Positive control (07/306), a Negative control (07/308), and a specifically formulated Limit preparation (07/310) to define the maximum (e.g. pharmacopoeial) limits of anti-A and anti-B in IVIG products, where limits are applicable. Laboratories performed direct haemagglutination using papain-treated erythrocytes and/or indirect antiglobulin tests., Results: For both methods, there was up to 16-fold variation in anti-A and anti-B titres, although there was good agreement over a two-fold titre range for anti-A and anti-B between laboratories for both 07/306 and 07/310 using the direct method. Comparative titration data for 07/306 and 07/310 indicated that the use of a 'Limit' reference reagent would facilitate identification of higher titre batches when the direct haemagglutination method is used., Conclusions: The establishment of preparations 07/306, 07/308 and 07/310 as reference reagents by the World Health Organization will facilitate global standardization of haemagglutination tests for anti-A and anti-B, ensure that such tests are sufficiently sensitive and specific, and facilitate identification of batches that exceed maximum recommended levels of anti-A and anti-B. The Commission of the European Pharmacopoeia and the United States Food and Drug Administration have adopted the same reference reagents including the maximal specifications defined by preparation 07/310.

The European Pharmacopoeia (Ph. Eur.) and the World Health Organization (WHO) require the performance of extensive quality control testing including a potency test before a vaccine batch is released for human use. Whole cell pertussis (wP) vaccine potency is assessed by a mouse protection test (MPT) based on the Kendrick test. This test compares the vaccine dose necessary to protect 50% of mice against the effect of a lethal intracerebral dose of Bordetella pertussis and the dose of a suitable reference vaccine needed to give the same protection level. Due to the large variability in the results of this test and the severe distress which is inflicted on the many animals involved, its replacement by an alternative method is highly desirable. At the initiative of the European Directorate for the Quality of Medicines and HealthCare (EDQM) of the Council of Europe, in collaboration with the WHO and the In-vitro toxicology Unit/European Centre for the Validation of Alternative Methods (ECVAM) of the European Commission (EC) Joint Research Centre-Institute for Health and Consumer Protection (JRC-IHCP), wP vaccine specialists from all over the world were invited to present an overview of candidate alternatives at a symposium organised in Geneva (Switzerland) in March 2005. Although no alternative method was found suitable for immediate implementation of batch potency control, the Pertussis Serological Potency Test (PSPT), initially developed in mice and recently transferred to guinea pigs (gps), was identified as a model of interest. Using the PSPT in gps to test several components of combined vaccines such as Diphtheria-Tetanus-wP vaccines in the same animal series would allow further implementation of the European 3Rs policy to batch potency control, by additional method refinement and reduction of animal use. The present study evaluated 2 features of the serological response to wP vaccination: 1) the overall antibody response as measured by a "whole cell" ELISA (PSPT-wC-ELISA) which uses the B. pertussis 18323 challenge strain prescribed for the MPT to coat the assay plates and 2) the functional neutralising antibodies to pertussis toxin (PT, one of the main virulence factors of B. pertussis), as measured by the Chinese Hamster Ovary (CHO) cell assay. The results showed that 1) the gp model can be used for wP vaccine potency testing; 2) despite good repeatability and precision, the CHO cell assay did not generate results comparable to the MPT. Moreover, the CHO cell assay showed significant differences in the ability of wP vaccines to induce neutralising anti-PT antibodies, which did not correlate to the overall antibody response evaluated by PSPT-wC-ELISA; 3) comparable potencies were obtained in the MPT and the PSPT-wC-ELISA. This study, supported by the previous ones correlating the PSPT-wC-ELISA in mice with the MPT, confirms that PSPT-wC-ELISA in gps is a promising approach for batch release potency testing of wP vaccines for which consistency in production has already been demonstrated by the MPT. However, a large scale validation study is required prior to the adoption of PSPT-wC-ELISA as a compendial reference method for wP vaccines batch release control.

In 2004, the Office International des Epizooties (OIE) Expert Surveillance Panel on equine influenza recommended that the American lineage component (H3N8) of equine influenza vaccines (A/eq/Newmarket/1/93-like) be updated to an A/eq/South Africa/4/03-like virus. As a consequence the common European Pharmacopoeia (Ph. Eur.) - OIE reference for equine influenza subtype 2 American-like antiserum had to be complemented by an antiserum raised in horses against an A/eq/South Africa/4/03 strain. An international collaborative study run by the European Directorate for the Quality of Medicines (EDQM) in the frame of its Biological Standardisation Programme (BSP) under the aegis of the Ph. Eur. and the OIE was organised. The study was aimed at evaluating a candidate reference horse anti-serum using the single radial haemolysis (SRH) and haemagglutination inhibition (HI) tests. The standard was to be established for use in immunogenicity and batch potency assay of equine influenza vaccines as a Ph. Eur. BRP and for use in clinical diagnostic tests as an OIE-approved International Standard. The evaluation performed in the collaborative study enabled the suitability of the candidate to be demonstrated and an SRH value to be assigned. The candidate was adopted as a BRP by the Ph. Eur. Commission and approved by the OIE Biological Standards Commission as an International Standard Serum in June and September 2006, respectively.

A study was carried out by the European Directorate for the Quality of Medicines (EDQM) as part of the joint Biological Standardisation Programme of the Council of Europe and the European Commission with the aim to establish replacement batches of the European Pharmacopoeia (Ph. Eur.) human immunoglobulin Biological Reference Preparation (BRP) batch 2. Twenty-eight laboratories participated in this study. The suitability of the candidate reference preparations to serve as working references in the tests for distribution of the molecular size, anticomplementary activity and Fc function, in accordance with the specifications of the Ph. Eur. monographs Human normal immunoglobulin for intravenous administration (0918), Human normal immunoglobulin (0338) and Anti-T lymphocyte immunoglobulin for human use, animal (1928) was demonstrated. The candidates were therefore established as human immunoglobulin BRP batch 3 and Human immunoglobulin (molecular size) BRP batch 1. The prescribed use of the latter BRP is limited to the test for distribution of molecular size.

An international collaborative study was organised to establish a European Pharmacopoeia (Ph. Eur.) Biological Reference Preparation (BRP) and United States (US) Food and Drug Administration (FDA) reference preparation for the test for anti-D (anti-Rho) antibodies in human normal immunoglobulin for intravenous administration (IGIV). A candidate positive control (IGIV+anti-D) and negative control IGIV were compared to corresponding World Health Organization (WHO) International Reference Reagents using a direct haemagglutination reference method. Sixteen (16) laboratories participated in the collaborative study. Further to completion of the study, the materials assayed in the study were granted the status of Ph. Eur. and US FDA reference preparations for controlling the levels of anti-D in IGIV.

Thirty laboratories participated in a collaborative study to calibrate replacements for the 1st International Standard for Low Molecular Weight Heparin and the European Pharmacopoeia Low-molecular-mass heparin for assay Biological Reference Preparation. Two freeze-dried materials and one liquid preparation were included in the study. All three samples gave excellent intra- and inter-laboratory variations (majority of mean % geometric coefficient of variation < 10 %) when assayed against the 1st International Standard by both anti-Xa and anti-IIa assays. There were no major differences found between potency estimates using all methods and that obtained using European Pharmacopoeia method only. Overall, this study showed that the differences between the candidates are marginal. Based on the results of the study Sample B, 01/608 was established as the 2nd International Standard for Low Molecular Weight Heparin. Sample A, 01/592 and sample C, the liquid preparation, were established as replacements for the European Pharmacopoeia 'Low-molecular-mass heparin for assay' Biological Reference Preparation.

The preparation and establishment of the 2nd European Pharmacopoeia (Ph. Eur.) Biological Reference Preparation (BRP) for erythropoietin was the goal of a project run within the framework of the European Biological Standardisation Programme. The project, coded BSP062, was carried out between October 2002 and July 2003. The candidate preparation (cBRP2) was prepared in a similar manner to the first BRP batch (BRP1), as follows: -50:50 (weight/weight) blending of the two erythropoietin preparations currently available on the European market (epoietin-alpha and epoietin-beta), -lyophilisation using a protein-free carrier formulation to allow use of the standard for both biological and physico-chemical assay methods, -each vial contains approximately 250 microg erythropoietin. The cBRP2 was analysed in a collaborative study, carried out with the following aims: -to calibrate cBRP2 by in vivo bioassay in terms of the International Standard for erythropoietin, and assign a unitage, -to demonstrate continuity of unitage with BRP1, -to evaluate the suitability of cBRP2 to serve as a reference material for physico-chemical tests of erythropoietin. The collaborative study involved 14 laboratories both from Europe, and from Australia, Canada, South-Korea and the United States of America. Participants carried out biological and physicochemical assays on the candidate BRP batch 2, using BRP 1 and the 2nd World Health Organization (WHO) International Standard (IS) for recombinant erythropoietin as the reference standards. It was demonstrated that: -an assigned potency of 32,500 U per vial would maintain continuity between BRP1 and BRP2 in terms of the IS for erythropoietin, -the replacement batch was appropriate for use as erythropoietin BRP in the context of the control of erythropoietin concentrated solutions according to the Ph. Eur. monograph 1316. In July 2003, the Ph. Eur. Commission established the proposed standard as 'Erythropoeitin BRP batch 2' for use as a reference preparation for the polycythaemic and normocythaemic mouse bioassay, with an assigned potency of 32,500 U/vial, the identification by capillary zone electrophoresis (CZE), by polyacrylamide gel electrophoresis, immunoblotting and peptide mapping and as a reference for checking the system suitability of size exclusion chromatographic procedures used in the test for 'Dimers and related substances of higher molecular mass'.

An international collaborative study aimed at establishing a global standard for the potency assay of anti-D immunoglobulin was started in 2002. 25 laboratories participated in this study run under the common aegis of the World Health Organization, the United States Food and Drug Administration (US-FDA) and the European Directorate for the Quality of Medicines (EDQM). The potencies of three candidate materials and the US-FDA standard (lot 3) included for comparison were evaluated using AutoAnalyzer, competitive enzyme-linked immunoassay (competitive EIA), flow cytometric methods or own "in-house" methods. Critical reagent, standardised procedures and standardised assay design were provided for either method, where appropriate. Central statistical evaluation of the potency data submitted by the participants was performed using a parallel line model. Agreement between laboratories and assay methods for all samples was observed. Intra-laboratory variability was lowest for laboratories performing flow cytometry and highest for laboratories that performed their in-house methods. Inter-laboratory variability was acceptable for all samples when assayed by AutoAnalyzer, competitive (EIA) and flow cytometric methods. It was concluded that sample A is most suitable to serve as a global standard and that sample C could serve as a reserve European Pharmacopoeia (Ph. Eur.) Biological Reference Preparation (BRP) batch provided that suitable stability is demonstrated. Sample A was adopted by the Ph. Eur. Commission at its 115th session (March 2003) as the first Ph. Eur. BRP (available from the EDQM: catalog number Y0000219) with the assigned potency of 285 IU/ampoule.

A collaborative study on the evaluation of an alternative functional assay, the Vero cell method, to the Ph. Eur. in vivo challenge procedures for potency determination of diphtheria toxoid in 6 different combined vaccines was initiated in January 2001. The study was an extension of a previous study for the validation of serological methods for potency testing of tetanus toxoid vaccines for human use. To allow interim evaluation of test results and to monitor study progress, the project was divided into three consecutive phases. The results of Phase I and II studies are presented in this report. Pre-validation (Phase I) study, performed in two laboratories, indicated that comparable diphtheria potency estimates were obtained in the Ph. Eur. direct intradermal challenge assay in guinea pigs, in Vero cell assay and in indirect ELISA for five vaccines of different potencies (range of estimates: ca. 20-200 IU/ml). The correlation coefficients between the challenge assay and the Vero cell assay corresponded to those between the challenge assay and ELISA, confirming that the antibodies play an important role in protection and that predominantly protective/neutralising antibodies are present in guinea pigs, at the time point investigated. It was observed, for Vero cell assays, that about 16-35 (9-28 in Phase II study) fold lower titre of individual serum samples were obtained when using equine, rather than guinea pig reference serum. The study also provided preliminary information that sera from the same guinea pigs may be used for potency determination of both diphtheria and tetanus toxoid components of vaccines. In Phase II, another five laboratories analysed a subset of the vaccines included in Phase I study plus an additional vaccine. Four laboratories performed the lethal challenge assay and one laboratory carried out the intradermal challenge assay. All laboratories also performed the Vero cell assay and both ELISA for diphtheria antitoxin and ELISA for tetanus antitoxin. One laboratory also performed the tetanus ToBI assay. The correlation coefficient (r) between Vero cell assay and ELISA for diphtheria antitoxin ranged from 0.76 to 0.91 in the different laboratories. The correlation between diphtheria serological assays and challenge assays were confirmed satisfactory as ca. 90 per cent of serum-estimates lead to correct prediction of mortality. All laboratories had identical rankings of the vaccines in all serological assays and in the valid challenge assays. The ranking order was identical to assumed/provided potency for the highest and the lowest vaccine. Two of the vaccines had an inversion in some assays and laboratories. As these two vaccines have almost identical potencies in all assays, these inversions are not significant. As the vaccine doses were optimised for the diphtheria component, serum anti-tetanus toxoid/toxin activities varied widely between the vaccines, making it questionable to apply a parallel line model to calculate exact potencies. However, the dose levels used showed a clear regression and good linearity in general. DTaP vaccines containing the IPV component did not always meet the present Ph. Eur. requirements in the serological assays. It should be further investigated in the Phase III study if this is a general feature of such combined vaccines. Preliminary investigations on samples from two laboratories indicate that the neutralising activity of type 1, 2 and 3 polioviruses can also be detected, in a dose-dependent way. Further studies are in progress with serum samples from other laboratories. In the light of results obtained in the first two phases, it is recommended to proceed with Phase III study to investigate reliability of the in vitro assays. In Phase III it will also be further investigated whether the serological assays for D and T components are suitable for the control of the multi-component vaccines currently marketed in Europe.

Phase I of BSP034 collaborative study was extended in two laboratories to include correlation of serology with in vivo toxin neutralisation test (TNT) using 2 separate sets of 20 serum pools, produced in-house. The study investigated the extent to which the in vitro methods for diphtheria antibodies, Vero cell assay and diphtheria enzyme-linked immunosorbent assay for diphtheria antitoxin (D-ELISA), can detect neutralising antibodies by comparison with TNT in guinea pigs. The study was also performed to compare the antibody neutralising potency obtained in relation to guinea pig (GP) or equine (DI) antitoxin standard. In addition, the study provided an opportunity to compare ELISA for tetanus antitoxin (T-ELISA) and TNT assay for detection of anti-tetanus antibodies, from the same set of serum pools. The data obtained show that antitoxin potency obtained by Vero cell assay, D-ELISA and T-ELISA using the same GP standard, highly correlated with neutralising potency as determined in respective TNT assays. Vero cell assay with DI provided estimates that also correlated with neutralising potency, but were of significantly lower titre. Since reference to DI standard is widely used in serodiagnosis, as well as in clinical studies where diphtheria antitoxin titres obtained in the Vero cell method are taken as surrogate markers for vaccine efficacy, it should be investigated if a similar difference is also observed for human serology.

Background and Objectives: The aim of the study was to evaluate a lyophilized anti-D immunoglobulin preparation to serve as a global standard for potency assays of anti-D immunoglobulin products., Materials and Methods: The candidate global standard, 01/572, was calibrated against the World Health Organization (WHO) International Reference Preparation (IRP) for anti-D immunoglobulin, human (68/419), along with two reserve candidate reference preparations, in an international collaborative study involving 25 laboratories in 15 countries. The United States Food and Drug Administration (US-FDA) Center for Biologics Evaluation and Research (CBER) Standard for anti-D immunoglobulin, Lot 3, was included for comparison. Most laboratories (20/25) performed AutoAnalyser methodology, competitive enzyme-linked immunoassay (EIA) and/or flow cytometry., Results: The overall mean potency of the candidate global standard, 01/572, was 284.5 international units (IU)/ampoule, with an interlaboratory variability, expressed as a percentage geometric coefficient of variation (% gcv), of 9.7. The mean potency of the US Standard was 859.4 IU/ml with an interlaboratory variability of 9.5% gcv, excluding an outlier. The mean potencies of the reserve preparations per ampoule/vial were 110.6 IU and 106.7 IU when calibrated against the IRP, and 112.2 IU and 106.6 IU when calibrated against 01/572, respectively, with interlaboratory % gcv values of 9.6-18.3 (excluding outliers)., Conclusions: Preparation 01/572 proved more suitable for use as a global standard than the reserve candidate preparations and was established, with an assigned potency of 285 IU/ampoule, by the WHO as the 2nd International Standard for anti-D immunoglobulin; by FDA-CBER as the Standard for anti-D immunoglobulin, Lot 4; and by the European Directorate for the Quality of Medicines (EDQM) as the 1st Biological Reference Preparation for anti-D immunoglobulin.

The European Directorate for the Quality of Medicines (EDQM) has organised an international collaborative study, divided in two phases, aimed at producing and establishing a suitable reference serum for serological potency testing of clostridial vaccines for batch consistency demonstration. In phase 1 a series of pools produced from sera provided by each manufacturer and raised against the broadest range of antigens possible were blended to obtain TN titres which were representative of the range normally elicited by the vaccines under test. Detailed statistical analysis of the data was not possible since only a few laboratories were able to participate and because limited replication of the assays was possible. Nevertheless, sufficient data were collected to conclude that the blend of sera would provide a suitable reference material for use by all manufacturers and regulatory authorities in respect of in vitro assay methods for the five components for which it was primarily designed, i.e. Clostridium (C.) perfringens beta and epsilon, septicum, novy and tetani. On the basis of these results a production scale blend of the serum pools was prepared, filled and freeze-dried by EDQM as a single batch, referred to as candidate (c) Ph. Eur. Biological Reference Preparation (BRP). In phase 2 of the study a larger group of laboratories, including both manufacturers and official medicines control laboratories (OMCL), were invited to participate in a study comparing the activity of the proposed rabbit multicomponent reference serum with the existing equine monovalent World Health Organization (WHO) International Standard (IS). These studies necessarily were conducted according to the methods described in the currently applicable monographs i.e. by toxin neutralisation test in mice (TN) to provide a definitive value for the antitoxin activity of the reference preparation in respect of the five components studied.

The European Directorate for the Quality of Medicines (EDQM) has organised an international collaborative study, divided into two phases, aimed at producing and establishing two suitable reference sera for serological potency testing of tetanus vaccines for veterinary use for batch consistency demonstration. In phase I pools of sera were produced by immunising guinea pigs and rabbits with tetanus toxoid using the immunisation schedule prescribed by the European Pharmacopoeia (Ph. Eur.) for potency testing of tenanus vaccines for veterinary use. Following aliquoting and freeze-drying, characterization of the materials by immunochemical and biological assays enabled us to conclude that the sera should be suitable reference materials in respect of in-vitro assay methods for Clostridium (C.) tetani. The candidate (c) Ph. Eur. Biological Reference Preparations (BRP) were calibrated by Toxin Binding Inhibition test (ToBI) in phase II of the study by a large group of laboratories, including both manufacturers and official medicines control laboratories (OMCL). The activity of the proposed reference sera was determined by comparison with the existing equine monovalent World Health Organization (WHO) International Standard (IS). This study enabled us to provide a definitive value for the antitoxin activity of the reference preparations in respect of their anti-tetanus antibody content.