Interchangeability of biosimilars: A study of expert views and visions regarding the science and substitution

Healthcare systems have reached a critical point regarding the question of whether biosimilar substitution should become common practice. To move the discussion forward, the study objective was to investigate the views of experts from medicines agencies and the pharmaceutical industry on the science underpinning interchangeability of biosimilars. We conducted an empirical qualitative study using semi-structured interviews informed by a cross-disciplinary approach encompassing regulatory science, law, and pharmaceutical policy. In total 25 individuals with experience within biologics participated during September 2018-August 2019. Eight participants were EU national medicines authority regulators, and 17 had pharmaceutical industry background: five from two originator-only companies, four from two companies with both biosimilar and originator products, and eight from seven biosimilar-only companies. Two analysts independently conducted inductive content analysis, resulting in data-driven themes capturing the meaning of the data. The participants reported that interchangeability was more than a scientific question of likeness between biosimilar and reference products: it also pertained to regulatory practices and trust. Participants were overall confident in the science behind exchanging biosimilar products for the reference products via switching, i.e., with physician involvement. However, their opinions differed regarding the scientific risk associated with biosimilar substitution, i.e., without physician involvement. Almost all participants saw no need for additional scientific data to support substitution. Moreover, the participants did not believe that switching studies, as required in the US, were appropriate for obtaining scientific certainty due to their small size. It is unclear why biosimilar switching is viewed as scientifically safer than substitution; therefore, we expect greater policy debate on biosimilar substitution in the near future. We urge European and UK policymakers and regulators to clarify their visions for biosimilar substitution; the positions of these two frontrunners are likely to influence other jurisdictions on the future of biosimilar use.

Reduction of Numbers of Animals Used in the Quality Control of Biologicals

Laboratory animals are used for the quality control of vaccines. In particular, the potency testing of batches of inactivated vaccine requires large numbers of animals. The possibilities for reduction have been evaluated, and the results are summarised in this paper. Several approaches were studied, including the retrospective analysis of test data, with the objectives of determining the minimum number of animals required per vaccine dilution group, and evaluating the feasibility of a single-dose potency test. Other studies focused on the development of serology-based models and the use of genetically uniform animals. Based on the outcome of these studies, a substantial reduction in the number of animals used for the potency testing of toxoid vaccines has been achieved or will be achieved in the near future. As reduction alternatives can generally be explored in a relatively simpler and less time-consuming way than replacement alternatives, more emphasis should be placed on reduction strategies than at present.

Biological agents and biosimilars: Essential information for the internist

Biologics embrace a wide range of substances synthesized by cells or living organisms by means of different biological processes, including recombinant DNA technology, controlled gene expression, or antibody technologies. A biosimilar establishes similarity to the reference medicinal product in terms of quality characteristics, biological activity, safety, and efficacy based on a comprehensive comparability exercise. Minimizing development costs and accelerating their market access create a convergence of interests between health services, worried about sustainability, and generic manufacturers. While the demonstration of bioequivalence is sufficient for small synthetic molecules, this approach is not scientifically applicable to a copy of biological drug constituted by large and complex molecules, which are similar but not identical to the originator and are also subject to different post-translational processes. Internists should be confident that the development process of biosimilars ensures a comparable risk-to-benefit balance with the originators. On the basis of available evidence and pharmacovigilance network, there are no grounds to believe that the use of a biosimilar carries more risks for the patient than the use of an originator. Since the first biosimilar was authorized in Europe in 2006, no clinical alerts have raised red flags about the established EMA biosimilar pathway. In this article, we discuss some of the most frequent concerns raised by clinicians about biosimilars and try to explains the scientific principles underlying the biosimilar concept established in the EU in order to license biosimilar drugs.

[Main direction of harmonization of Russian and international requirements on providing of biological safety when handling pathogenic biological agents]

The actuality of harmonization of Russian and international requirements when handling with pathogenic biological agents (PBA) is caused by the need to ensure biological security on the basis of control of biorisks. One of the basic conditions for harmonization is development and implementation of the Russian standard for biorisk management based on international standard CWA 15793:2008.

Stability studies needed to define the handling and transport conditions of sensitive pharmaceutical or biotechnological products

Many pharmaceutical or biotechnological products require transport using temperature-controlled systems to keep their therapeutic properties. There are presently no official guidelines for testing pharmaceutical products in order to define suitable transport specifications. After reviewing the current guidance documents, this paper proposes a methodology for testing pharmaceutical products and defining appropriate transport conditions.

WHO Expert Committee on biological standardization

This report presents the recommendations of a WHO Expert Committee commissioned to coordinate activities leading to the adoption of international recommendations for the production and control of vaccines and other biologicals and the establishment of international biological reference materials. The report starts with a discussion of general issues brought to the attention of the Committee and provides information on the status and development of reference materials for various antibodies, antigens, blood products and related substances, cytokines, growth factors, and endocrinological substances. The second part of the report, of particular relevance to manufacturers and national regulatory authorities, contains WHO recommendations and guidelines on Japanese encephalitis vaccine (inactivated), human; regulatory preparedness for human pandemic influenza vaccines; and clinical evaluation of meningococcal C conjugate vaccines. Also included are a list of recommendations, guidelines and other documents for biological substances used in medicine, and of international standards and reference reagent for biological substances.

Allergen source materials: state-of-the-art

A variety of positive outcomes can be realized from validation and risk management activities (see Table 4). They are dependent on the participation of multiple functional groups including the quality unit, regulatory and legal affairs, engineering and production operations, research and development, and sales and marketing. Quality risk management is receiving increased attention in the area of public health, pharmacovigilance, and pharmaceutical manufacturing. Recent examples of its regulatory use in our industry include the assessment of the potential risks of transmissible spongiform encephalopathies (TSE) agents through contaminated products], the risks of precipitates in allergenic extracts, and the revision of the potency limits for standardized dust mite and grass allergen vaccines. Its application to allergen source material process validation activities allowed for a practical strategy, especially in a complex manufacturing environment involving hundreds of products with multiple intended uses. In addition, the use of tools such as FMEA was useful in evaluating proposed changes made to manufacturing procedures and product specifications, new regulatory actions, and customer feedback or complaints. The success of such a quality assurance programs will ultimately be reflected in the elimination or reduction of product failures, improvement in the detection and prediction of potential product failures, and increased confidence in product quality.

Physicochemical characterization of allergens: quantity, identity, purity, aggregation and conformation

Allergens and allergoids can be characterized by means of physicochemical methods, resulting in a description of the protein on different structural levels. Several techniques are available and their suitability depends on the composition of the particular sample. Current European legislation on allergen products demands characterization of final products in particular focusing on identity, degree of modification (for allergoids) and stability of the composition. Structural parameters of allergens may be used to investigate the stability of an allergen product. The challenge is to identify and optimize techniques that allow determination of protein structure in the context of a formulated pharmaceutical product. As the majority of the products currently marketed are formulated with aluminium hydroxide or aluminium phosphate as a depot, most of the methods and techniques used for protein characterization in solution are not applicable. An additional hurdle is that allergen products are based on natural extracts, comprising a mixture of proteins, both allergens and non-allergens, sometimes in the presence of other uncharacterized components from the raw material. This paper describes which methods are suitable for the different stages of allergen product manufacturing, and how these relate to the current regulatory requirements. Some of the techniques are demonstrated using a model allergen, cod parvalbumin, and a chemically modified form thereof. We conclude that a variety of methods is available for characterization of proteins in solution, and that a limited number of techniques appear to be suitable for modified allergens (allergoids). Adaptation of existing methods, e.g. mass spectroscopy and infrared spectroscopy may be helpful to obtain protein parameters of allergens in a formulated allergen product. By choosing a combination of techniques, including those additional to physicochemical approaches, relevant parameters of allergens in formulated allergen products can be assessed in order to achieve a well-characterized pharmaceutical product.

Safety evaluation of natural flavour complexes

Natural flavour complexes (NFCs) are chemical mixtures obtained by applying physical separation methods to botanical sources. Many NFCs are derived from foods. In the present paper, a 12-step procedure for the safety evaluation of NFCs, 'the naturals paradigm', is discussed. This procedure, which is not intended to be viewed as a rigid check list, begins with a description of the chemical composition of the commercial product, followed by a review of the data on the history of dietary use. Next, each constituent of an NFC is assigned to one of 33 congeneric groups of structurally related substances and to one of three classes of toxic potential, each with its own exposure threshold of toxicological concern. The group of substances of unknown structure is placed in the class of greatest toxic potential. In subsequent steps, for each congeneric group the procedure determines the per capita intake, considers metabolic pathways and explores the need and availability of toxicological data. Additional toxicological and analytical data may be required for a comprehensive safety evaluation. The procedure concludes with an evaluation of the NFC in its entirety, also considering combined exposure to congeneric groups. The first experiences with the use of this procedure are very promising. Future safety evaluations of larger numbers of NFCs will indicate the usefulness of the system, either in its present form or in a form modified on the basis of experience.

Three Rs potential in the development and quality control of immunobiologicals

Immunobiologicals (vaccines, immunoglobulins and -sera) are considered to be the most cost-effective tools in the prevention of infectious diseases. Their importance will further increase due to various eradication programmes of the WHO and EU and the emergence of new infectious diseases or the re-emergence of diseases as diphtheria and tuberculosis. The production and quality control of immunobiologicals are regulated by monographs and guidelines, which are issued by international or national Pharmacopoeias (e.g. Ph. Eur.), international organisations (e.g. WHO, O.I.E.) and international regulatory bodies (e.g. EMEA). Their purpose is to assure the quality of the product, i.e. its safety and potency. It is estimated that 10 millions of laboratory animals are world-wide used for the production and quality control of immunobiologicals, of which 80% are needed for the safety and potency testing of the finished product (batch control). In recent decades, the use of Three Rs principles has been recognised by the above mentioned organisations and various national competent authorities and been incorporated into general monographs and guidelines. Several tests with questionable relevance have been deleted from Ph. Eur. monographs (e.g. abnormal toxicity test, extraneous agents testing of viral vaccines for carnivores) or are now carried out during production. Reduction of the number of animals used could be achieved by introducing single-dilution tests. A large number of immunochemical tests have been developed, which could completely or partly replace the use of animals for potency testing, however, only a few have been validated so far (e.g. ToBI and ELISA for potency testing of human and veterinary tetanus vaccine; ELISA for potency testing of erysipelas vaccine). Regulatory acceptance of validated alternative methods is still a critical step. In particular, the period between successful validation and the implementation appears to be far too long. Reasons for this could be the slow process of multinational agreement to revise pharmacopoeial monographs and guidelines, and the time-consuming and expensive production of sufficient reference material (antigen, sera etc) for the new test systems. The shift in the quality control concept from reliance on final batch testing to the concept of consistency of production offers the opportunity to reduce the numbers of animals being used and promote the use of alternative methods. Emphasis is put on a combination of in vitro tests, which could make it possible to monitor batch-to-batch consistency. This new concept of quality control is already in place for the new well-defined vaccines. In most cases, non-animal methods are used for monitoring consistency at critical steps in the production and testing of a vaccine. Whether the concept of consistency of production could be also applied to the conventional, less-defined products, should be investigated. Only little progress has been achieved with regard to international harmonisation. Most of the manufacturers produce for the world market, so harmonisation of the requirements or mutual recognition of tests would help to reduce the use of animals. There is agreement that for the time being animals will still be needed for the development of vaccines in order to gain best knowledge on the disease, the pathogen and the specific immune response, including: pathogenesis, identification of the protective antigens, the way the antigen is processed, the dynamics of the immune response, the induction of memory, and the selection of the best adjuvant. With regard to routine batch release of conventional products, a number of Three Rs approaches are already available and should further be developed and validated. Whereas routine batch release of new products should be based on in vitro methods already established during their development.

Isolation of endogenous anticoagulant N-sulfated glycosaminoglycans in human plasma from healthy subjects

Endogenous N-sulfated glycosaminoglycans (GAGs) comigrating with standard heparin and sensitive to nitrous acid treatment were isolated from plasma of healthy donors. The amount of these compounds was 7-10 microg/ml, and activated partial thromboplastin time, anti-Xa and anti-IIa activities were similar to those of standard heparin of high molecular mass. Analysis with gradient PAGE of the putative endogenous heparin showed a mean molecular mass of 12 kD. These N-sulfated GAGs could be isolated only after removal of binding peptides that impaired purification by ion-exchange chromatography. We used SDS-PAGE as a tool to separate peptides from endogenous GAGs. N-sulfated GAGs exited the gel before peptides when the electrophoresis was overrun. Endogenous GAGs could be recovered by ion-exchange chromatography of the SDS-PAGE buffer, 'free' from associating peptides. These results strongly support the hypothesis that endogenous heparin is associated in vitro with a variety of proteins and that this association could be responsible for modification of both heparin and protein activities.

Human biological materials in research: ethical issues and the role of stewardship in minimizing research risks

Recent scientific and technologic advances generated from the human genome project have increased the ability of researchers to study human biological materials. This has enhanced the ease with which highly personal information such as genetic makeup can be revealed about individuals, families, and communities. In addition, a change in the societal value of human biological tissue from waste to commercial resource has occurred. A new model of stewardship is developed that can be used as a guide for protecting human research participants who are involved in studies that include collecting and handling human biological samples. Nursing implications to ensure protection of human research participants are discussed.

Final rule

The Food and Drug Administration (FDA) is issuing a final rule to require human cells, tissue, and cellular and tissue-based product establishments to register with the agency and list their human cells, tissues, and cellular and tissue-based products. FDA is also amending the registration and listing regulations that currently apply to human cells, tissues, and cellular and tissue-based products regulated as drugs, devices, and/or biological products. These actions are being taken to establish a unified registration and listing program for human cells, tissues, and cellular and tissue-based products.

qNMR--a versatile concept for the validation of natural product reference compounds

The validation of reference compounds for natural products is a domain of the same physico-chemical methods that are used for their isolation, especially those techniques involving coupled high-resolution chromatography. Acknowledging the great problem of co-eluting impurities contained in the 'biogenetic cocktail' of a plant extract, there is a strong demand for non-chromatographic alternatives in the quality assessment of reference compounds. Because of this, the concept of qNMR is introduced as a versatile tool based on qualitative and quantitative 1H-NMR allowing the precise and simultaneous determination of both the compound content as well as the amount and nature of the impurities. As opposed to measuring carbons, 1H-NMR benefits from much higher sensitivity and is far more versatile for routine analysis with respect to time and cost. Since quantification of impurities is reliant upon their identification and, therefore, limited by knowledge about their structure, the concept emphasizes the high demand for qualitative reference dossiers including quality NMR data for profiling potential impurities which may be analogues, isomers, or degradation or oxidation products of the reference compounds. The qNMR concept is developed with focus on its potential in the certification and quality control of reference compounds. Taking into account published work in the field of quantitative NMR, selected natural products are analysed in order to elaborate suitable experimental parameters and to obtain preliminary validation data. The method is discussed with respect to sensitivity, precision and selectivity. Typical relative errors are found to be below 2% for the quantification of both the major analyte and the minor impurities even when the latter are contained at the 1% level only. Documentation of the conformity of signal integration and precision is based on measurements of a certified reference standard. Determination of the natural 13C isotope is suggested as an elegant method of validation because the content values could be reproduced with errors below 1%. The qNMR concept offers a rapid and efficient way to assess the purity of natural products in a single analytical step without the need of performing multiple analyses, while still offering the option to retain the substance. Thus, qNMR pays tribute to the increasing demands in reference compound certification, but also holds out the prospect of easy access to the valid characterisation of natural products tested in vitro or in vivo for their biological and pharmacological effects.

[Regulation of natural medicines in Israel and abroad]

Hand-in-hand with the public's growing interest in health care, there has been an increasing demand for natural health products considered both safe and medically effective. But many such products have not been shown to meet efficacy and safety criteria and therefore can not be registered as pharmaceuticals. On the other hand, it is quite clear that some products do have pharmacological activity and are being used for therapeutic or preventive effects. In Israel, the marketing rules for food or dietary supplements prevent their manufacturers from claiming medicinal/healing properties that the product might have, and allow only limited health statements. But great demand for these products has created massive publication attributing medicinal indications for products whose quality, efficacy and safety have neither been examined nor proven according to accepted medical criteria. We review the regulation and supervision of natural health products in Israel and other developed countries and find a broad range of opinions about natural health products. They range from acceptance as conventional drugs reimbursable by health insurance, as in Switzerland and Germany, to their status as dietary supplements requiring no significant authorization or supervision, as in the USA. Analysis of the current situation in Israel and the western world would indicate that some natural health products do possess pharmacological activity and therefore manufacturers should be allowed to make limited claims for specified therapeutic properties. A stricter set of registration regulations are needed for proof of safety, efficacy and quality of these products, but more lenient than those for registering a pharmaceutical product.

WHO Expert Committee on Biological Standardization: highlights of the 50th meeting, October 1999

Biological medicines, which include vaccines, blood products and biological therapeutics, have historically played a dominant role in improving world health and are expected to make an increasingly important contribution to public health in the 21st century. Recent scientific and biotechnological developments have opened the way to novel products, new production methods and to highly sensitive assay procedures. However, the nature of biologicals, and especially new vaccines, blood products and therapeutics, raises particular questions regarding their standardization and quality control. These relate both to efficacy and to safety not only for the individual recipient but also for the population at large. Such advances highlight the complex issues surrounding standardization and control of biologicals, issues that need to be addressed on an international level.

European regulatory issues

Current EU regulations do not cover all aspects of the manufacture and control of blood products. Recent legislation coming into force on 1 January 1995 has established the European Medicines Evaluation Agency and introduced revised systems for approving pharmaceutical products, including blood products. There remains a need for comprehensive harmonized legislation covering plasma collection and screening, virus validation studies, and batch release.

[The sterility of blood products manufactured in Ukraine]

The author reports results of examination for sterility of 3100 series (7343 samples) of hemocorrectors that were received for State control from zonal blood transfusion stations in the Ukraine from 1987 through 1990. Four of them proved non-sterile. Strict surveillance for aseptics and antiseptics at all stages of the technological process will ensure sterility of all hemotransfusion media obtained from the blood transfusion services.

[ELISA diagnosis for Mycoplasma pneumoniae infection with human normal immunoglobulin products as control sera]

It was found that the human normal immunoglobulin G product, prepared from pooled plasma of at least 1,000 normal human donors, contained some specific IgG antibodies to Mycoplasma pneumoniae by Western blotting. M. pneumoniae-ELISA OD values increased linearly from 25 to 800 micrograms/ml in the concentration of the product, there were no differences in the M. pneumoniae-ELISA OD value of the products among lots. Then we used this product as control serum for measurement of IgG antibodies to M. pneumoniae in human sera by ELISA and compared the results with those obtained by complement fixation (CF) and indirect hemadosorption (IHA) tests. ELISA titers determined by this method had a mutual relation with CF and IHA titers.