Исследования иммуногенности терапевтических белков: методические аспекты выявления и изучения антител к лекарственному препарату 1 Федеральное государственное бюджетное учреждение «Научный центр экспертизы средств медицинского применения» Министерства здравоохранения Российской Федерации, 127051, г.Москва, Российская Федерация 2 Федеральное государственное бюджетное учреждение «Центр стратегического планирования и управления медико-

INTRODUCTION. The stability assessment of biological medicinal products (BMPs) requires special approaches and regulatory requirements. Therefore, BMPs require relevant national guidelines, which are an important prerequisite for the assurance of the safe and effective use of BMPs.AIM. This study aimed to analyse national and international requirements for the stability assessment of BMPs in order to use the results to inform future development of a unified regulatory approach to estimating and confirming shelf-life periods for BMPs.DISCUSSION. Most biotechnological medicinal products (BTMPs) are proteins and are highly sensitive to environmental factors by nature. Therefore, the shelf life of a BTMP is established on the basis of real-time stability studies. Stability testing under accelerated and stress conditions is conducted to support shelf-life claims and to characterise the mechanism of protein structure degradation. The results of accelerated and stress studies can be used to select the most sensitive stability-indicating parameters and testing methods. National and international regulatory authorities have developed specialised guidelines for stability studies of BMPs of various origins, and the stability assessment approaches in the regulatory system of the Eurasian Economic Union (EAEU) are harmonised with international standards. Special considerations associated with the stability of vaccines imply that stability studies of vaccines should not only establish shelf life but also investigate stability after reconstitution and after short-term temperature excursions from the recommended cold-chain conditions.CONCLUSIONS. Special stability testing considerations for various groups of BMPs (including BTMPs and immunobiologicals) indicate the need to develop and improve the system of requirements for BMP stability assessment. This will facilitate the optimisation of the life cycle of BMPs in the Russian Federation and the other EAEU member states.

INTRODUCTION. Vaccination is recognised as the only effective method for preventing rotavirus disease. Rotavirus remains a leading cause of death in young children, mainly, in developing countries. Currently, oral rotavirus vaccines for infant immunisation are available worldwide, and novel types of rotavirus vaccines are also under development, in particular, in the Russian Federation. However, there are no regulations or guidelines helping developers to design an optimal preclinical and clinical programme for rotavirus vaccines.AIM. This study aimed to analyse and summarise global experience in planning and conducting preclinical and clinical studies of rotavirus vaccines in order to provide recommendations for national vaccine developers.DISCUSSION. This study presents an analysis of the available data (and, specifically, the data obtained for the past five years) on all rotavirus vaccines used in the world that have been clinically proven to be effective in preventing severe rotavirus gastroenteritis and reducing the number of hospital admissions due to acute intestinal infections. The effectiveness of rotavirus vaccines varies in different regions of the world and may be lower in developing countries for various reasons. The safety profile of oral rotavirus vaccines is generally considered favourable. Nevertheless, there are still some concerns regarding intestinal intussusception in infants following vaccination. To address the abovementioned problems, researchers, including those in Russia, are developing novel types of rotavirus vaccines, predominantly focusing on inactivated (subunit or recombinant) preparations. For planning and conducting preclinical studies of a rotavirus vaccine, it is advisable to adopt general approaches that involve assessing the acute and chronic toxicity, immunogenicity, and safety pharmacology of the rotavirus vaccine and the virus-neutralising activity of vaccination-induced antibodies. Clinical trials of a rotavirus vaccine should assess its effectiveness in preventing rotavirus gastroenteritis of any severity, hospitalisation, and acute viral intestinal infections of any aetiology in the target age group of young children. Furthermore, it is important to confirm the safety of the rotavirus vaccine and demonstrate the absence of mutual interference with the immunogenicity of the rotavirus vaccine and other vaccines co-administered in the vaccination schedule.CONCLUSIONS. Preclinical studies of rotavirus vaccines may use standard and generally accept­ed approaches. However, planning and conducting clinical trials requires specific considerations associated with both the nature of rotavirus infection and the national infant vaccination schedule.

Vaccines are subject to specific regulatory requirements for the evaluation of their quality, safety, and efficacy. In 2005, the World Health Organisation (WHO), as the main international organisation coordinating measures to combat infectious disease outbreaks, began developing documents on the evaluation of vaccine quality, safety, and efficacy. The world’s leading regulatory authorities (FDA, EMA, etc.) have also issued recommendations for conducting non-clinical studies of vaccines.The aim of this study was a critical review of the regulatory requirements established by foreign national and international regulatory authorities for non-clinical evaluation of the safety and efficacy of vaccines.According to the study results, since the 2000s, the WHO and the world’s leading regulatory authorities have produced more than 40 regulatory documents describing certain aspects of non-clinical studies of the safety and efficacy of vaccines. These documents can be divided into two groups: the first group addresses non-clinical studies of vaccines in general, and the second one dwells upon the evaluation of the quality, safety, and efficacy of specific types of vaccines. For the Russian guidelines on non-clinical evaluation of the quality, safety, and efficacy of immunobiologicals, the latest revision dates back to 2013 and does not provide any information on new medicinal products. Currently, work is underway to prepare the regulatory framework for medicines, including vaccines, in the Member States of the Eurasian Economic Union (EAEU). This review of regulatory documents on non-clinical safety and efficacy studies of vaccines may be useful in drafting harmonised guidelines for the relevant groups of vaccines in the EAEU. It may also be of use to developers, manufacturers, and researchers involved in the creation and non-clinical study of vaccines.

Scientific relevance. In recent years, the development of various vaccines based on novel platforms has underscored the significance of updating regulatory requirements for vaccines. Consequently, clinical trials of viral vaccines need harmonised approaches within national guidelines and the Eurasian Economic Union (EAEU) regulatory framework.Aim. This study aimed to analyse national and international requirements for clinical trials of the efficacy and safety of preventive viral vaccines.Discussion. This article presents an analysis of the guidelines issued by the WHO and leading regulatory authorities on different aspects of clinical trials of viral vaccines. These guidelines place particular emphasis on the immunogenicity of vaccines. The lack of well-established immune correlates of protection for most infections presents a significant problem for assessing the effectiveness of vaccines. Immunobridging studies may be conducted to expand vaccine indications to different populations (such as a new age group). The size of the prelicensure safety database should include data on at least 3,000 vaccinated study participants. For some vaccines, safety studies must assess the risk of disease onset or enhancement due to vaccination.Conclusions. The clinical trial requirements for viral vaccines have been substantially aligned by the WHO and major international regulatory authorities, thereby facilitating the development of harmonised national or EAEU guidelines.

Эффективность применения препаратов на основе иммуноглобулинов плазмы и моноклональных антител для лечения и профилактики COVID-19Федеральное государственное бюджетное учреждение «Научный центр экспертизы средств медицинского применения» Министерства здравоохранения Российской Федерации, 127051, г.Москва

At the end of 2019, an outbreak of a new coronavirus began in the city of Wuhan (Hubei Province) in the People's Republic of China. The outbreak turned into a pandemic. In the shortest possible time, national and international manufacturers developed preventive COVID-19 vaccines, and the population was vaccinated. During pandemics, accelerated approval of vaccines is an important factor that shortens the time to market with the aim of mass vaccination. The experience of rapidly developing and introducing vaccines into routine practice is not only important for managing the current pandemic, but also valuable in case of extremely likely future ones. The aim of this study was to analyse the main issues associated with assessing the safety and efficacy of vaccines for COVID-19 prevention during their registration and widespread use amid the pandemic and ongoing SARS-CoV-2 evolution. The vaccines for COVID-19 prevention were developed and introduced into healthcare practice very rapidly and under the circumstances of the pandemic, and the use of these vaccines has surfaced a number of concerns requiring further research. The most important issues identified in the performed analysis include, but are not limited to the need for accelerated assessment of the safety and immunogenicity of new vaccines; the lack of immune correlates of protection against SARS-CoV-2; the waning of antibody immunity over time, motivating the need to determine revaccination and post-recovery vaccination timelines; and the emergence of mutant SARS-CoV-2 variants. One of noteworthy aspects is the need to develop recommendations for updating the strain composition of registered COVID-19 vaccines. According to the conclusions, the level of herd immunity, including vaccine-induced protection, plays a certain role in virus evolution during the pandemic. If COVID-19 becomes seasonal, which is a probable scenario, regular revaccination can be essential.

There are a lot of diseases known today, which are caused by genetic abnormalities. Advances in genetics and biotechnology brought about gene editing technologies that can produce almost any gene, which ultimately led to the emergence of a new class of medicines - gene therapy products (GTPs). The aim of the study was to analyse international experience in development and authorisation of GTPs. The review highlights the challenges in GTP development, related to the search for an optimal approach to therapeutic gene delivery to the target cells. Viral vectors were shown to be a promising gene delivery system, with adenovirus (AV) and adeno-associated virus (AAV) based products demonstrating the highest efficacy and safety. The paper reviews current approaches to gene editing that allow modification of AVs and AAVs to improve GTP efficacy and safety. These modifications are carried out with the aim of, e.g., including a large therapeutic gene into a viral vector, decreasing viral protein expression levels, and decreasing viral vector immunogenicity. The review summarises GTP authorisation procedures in the USA and the European Union, including data on FDA and EMA subcommittees and departments entrusted with advisory functions. The paper mentions that there is one Russian-produced GTP authorised in the Russian Federation, and some other GTPs are in the pipeline. Therefore, the Russian regulatory framework and the Eurasian regulations and recommendations should be updated in order to accommodate for GTP development and authorisation.

At present, there are not much data on the clinical use of live recombinant viral vector vaccines. Characteristics of new vaccines should be factored into requirements/recommendations for quality control, preclinical and clinical studies of vaccines in order to enable further risk/benefit assessment. The aim of this study was to analyse current approaches to quality control, preclinical and clinical studies of live recombinant viral vector vaccines. The paper provides an overview of the licensed live viral vector vaccines and those at various stages of clinical trials. The authors analysed Russian, European, American, and Japanese guidelines related to quality issues, preclinical and clinical studies of live viral vector vaccines. The analysis demonstrated that the regulatory requirements for live recombinant viral vector vaccines include assessment of a detailed rationale for vaccine development, including information on the choice of the vector, the origin of the heterologous antigen gene(s), elements related to the transgene(s) expression, as well as assessment of the genetic and phenotypic stability of the recombinant virus, the risk of reversion to virulence or recombination with wild type strains, the potential for virus genome integration into the host cell chromosome, the pre-existing immunity to the vector, the intensity of the immune response elicited by the vector, and the reusability of the vector. The choice and number of applicable toxicological and pharmacological models will depend on these aspects. The results of the analysis of approaches to quality control, preclinical and clinical studies of live recombinant viral vector vaccines may be used in the development of Russian regulatory guidelines harmonised with the international norms and regulations.

Continuous replacement therapy with clotting factor products can lead to serious complications in haemophilia A patients. One of potential reasons of such complications is an undesirable immune response to a blood clotting factor VIII (FVIII) product, which undermines the treatment effectiveness. The aim of the study was to systematise and summarise data on undesirable immunogenicity of plasma-derived and recombinant FVIII products, formation of immunological tolerance, and modern approaches to the development of clinical trial programmes for such products. The analysis was based on scientific literature, as well as Russian and international guidelines, including the updated document of the European Medicines Agency. The paper presents clinical trial data on pharmacokinetics, efficacy, and safety of FVIII products, including data on manifestations of unwanted immunogenicity. It highlights molecular mechanisms of interaction between inhibitors and FVIII, and analyses the main factors (genetic characteristics, immune status of patients, dosage regimen, etc.) affecting the frequency and intensity of the immune response to the product. The authors summarised approaches to the clinical trial design, including selection of patients and studied parameters. They substantiate the need for post-authorisation studies to collect additional clinical data on both efficacy and safety of the routine use of the product, including additional assessment of immunogenicity and other adverse reactions. It is concluded that the successful use of high-quality FVIII products ensures by harmonisation of requirements of Russian and international regulatory documents.

Проблемы, связанные с проявлением иммуногенности биотерапевтических белков, и пути их решения 1 Федеральное государственное бюджетное учреждение «Научный центр экспертизы средств медицинского применения» Министерства здравоохранения Российской Федерации, 127051, г.Москва, Российская Федерация 2 Федеральное государственное автономное образовательное учреждение высшего образования «Первый Московский государственный медицинский университет им.И.М

According to the World Federation of Hemophilia (WFH), there are currently about 400 thousand patients with hemophilia in the world. Severe clinical manifestations of the disease associated with a genetically determined deficiency of blood clotting factor activity require continuous replacement therapy with blood clotting medicines. Long-term use of protein-based medicines often leads to the formation of specific antibodies, which causes a decrease in or loss of efficacy of the medicine or results in severe adverse reactions, including anaphylaxis. Therefore, it is important to search for new optimal approaches to hemophilia treatment, which requires the development of new blood clotting factor products, improvement of the production technology for already authorised products, as well as the use of non-factor products. The aim of the study was to present the results of the analysis of key issues related to the development and characteristics of plasma-derived and recombinant factor VIII products, new approaches to hemophilia A treatment, including the use of non-factor products. The review summarises current data on the etiology, clinical manifestations, and complications of hemophilia A treatment. It provides information on the blood clotting factor products (plasma-derived and recombinant) used as replacement therapy. It also provides information on advanced research projects for the development of new biotechnology-derived products which have good prospects of successful clinical use.

The efficacy and safety of the use of biotechnological (biotherapeutic, genetic engineering) preparations are due to their targeted mechanism of action and low of toxicity, in contrast to traditional chemicals drugs. These features of biotherapeutic preparations also aff ect their safety profile. When treating with biotherapeutic preparations, the most major adverse reaction and the first developmental time is the so-called infusion reaction. The basis of the development of the reaction to the infusion of a biotherapeutic preparation may be one of the following reactions: cytokine release syndrome (CRS), type I hypersensitivity reaction (IgE-dependent allergic reaction) or IgG-mediated reaction. These reactions have a similar clinical picture, so it is difficult to clearly determine which mechanisms led to the development of the reaction to the infusion. The mechanisms of development of the reaction to the infusion are still poorly studied.

Hemophilia is an orphan disease associated with deficiency or complete lack of certain blood coagulation factors due to mutation of genes encoding their synthesis. Patients with hemophilia need continuous replacement therapy with coagulation factor products which are produced by recombinant DNA technology or derived from donated blood plasma. The development of new products or improvement of the production process of already authorised medicinal products involve clinical trials that have to include both previously treated and untreated patients of different age groups. The aim of the paper was to perform an analytical review of general hemophilia issues and major requirements for clinical trials of coagulation factor IX products based on the updated documents of the European Medicines Agency. The paper summarises the basic principles of conducting clinical trials of coagulation factor IX products that are submitted for marketing authorisation as “new” products, based on recommendations of Russian and international regulatory documents, including the updated guideline of the European Medicines Agency. It sums up product safety issues associated with undesirable immunogenicity resulting in formation of inhibitors that provoke allergic reactions or reduce the effectiveness of therapy. The harmonisation of the requirements for clinical trials during preparation and updating of documents by Russian manufacturers should be based on the analysis of the experience with hemophilia products and latest scientific achievements in the disease treatment. In that case it will facilitate the introduction of innovative efficacious hemophilia products into clinical practice.

The progress of the COVID-19 pandemic initiated research to develop vaccines against this novel coronavirus infection. The WHO and national regulatory authorities in many countries have elaborated guidelines to speed up the development and authorisation of COVID-19 vaccines. The aim of the study was to analyse international and Russian regulatory recommendations for the development and fast-track approval of COVID-19 vaccines in the context of the pandemic, as well as to summarise the preliminary published results of the first stages of preclinical and clinical studies. The paper analyses approaches to fast-track approval of medicines in the face of the pandemic in Russia, the European Union, and the United States. It summarises regulatory requirements for the quality of COVID-19 vaccines, as well as for preclinical, and clinical studies. It describes the first results of COVID-19 vaccine development. The analysed regulatory documents allow for accelerated authorisation due to reduction of time spent on evaluation of vaccine quality, safety, and efficacy. Another option is the so-called conditional marketing authorisation when a vaccine is registered based on incomplete preclinical and clinical data provided that all the studies will be completed after the vaccine authorisation. The paper summarises the results of clinical trials of COVID-19 vaccines. The few published preliminary results of the first phases of COVID-19 vaccine clinical trials demonstrate the vaccines’ good tolerability, safety, and immunogenicity. Evaluation of adenovirusbased vaccines showed that almost half of the volunteers had had high antibody titers to adenovirus before the study, which resulted in milder adverse reactions and low immunogenicity. In addition, the immune response was weaker in the older group of subjects (45–60 years) as compared to the subjects younger than 45 years. The results of the analysis of regulatory requirements for the development and marketing authorisation of COVID-19 vaccines in the context of the pandemic, as well as of national and international regulatory approaches to vaccine development and authorisation can be used as a basis for the development of Russian requirements for COVID-19 vaccines in the context of the pandemic.

Review of materials related to scientific principles underlying clinical trials of coagulation factor IX medications obtained using recombinant DNA technique or from donors’ blood plasma. Inherited deficiency of functional active coagulation factor IX or a low level of its synthesis lead to the development of hemophilia B. Patients with hemophilia require a continuous replacement therapy with factor IX medications. Achievements in the area of genetically engineering technologies as well as improvement of production process of biological products allow developing modern highly efficient medications which are successfully used to treat patients with hemophilia. Registration of newly developed medications and medications produced according to the modified technology requires clinical trials. Principles of these trials are regulated by the clauses of regularly updated regulatory documents. Compliance with national and international guidelines determining the conditions for clini‑ cal trials of medications allows us to guarantee their safety and promotes the development of medications efficient to treat patients with hemophilia.

European competent authorities began to elaborate scientific principles of development of non-innovator biotherapeutic (biosimilar) products in the early noughties, and in 2009 these principles were approved at the WHO International Conference in Seoul gathering participants from countries with a well-developed pharmaceutical industry. The USA adopted the law on biosimilar products in 2012, it was based on the documents and recommendations prepared by the EMA and approved by the WHO. In 2015, the FDA published the new revised versions of the guidelines dealing with biosimilar products. The US regulatory requirements for development and authorisation of biosimilar products are based on a step-by-step comparative assessment of biosimilar and innovator products in terms of their quality, efficacy, and safety in accordance with the WHO/EMA recommendations. At the same time the US regulatory requirements differ from those of other national authorities, including EMA (WHO), when it comes to the design of comparative quality studies (studies of products’ physicochemical and biological properties), the assignment of International Non-Proprietary Names and the interchangeability of biosimilar products.

The review provides with the information, related to the development, research and registration of new biological preparations, including the issues of terminology and classification. It also highlights the issues of and prospects for genetically engineered drugs, specific aspects of comparative studies to prove the similarity of a biosimilar and the original (reference) medicine, clinical use and interchangeability of preparations, prospects for the development of biotechnological medicines, expert evaluation of the quality of biological/ biotechnological medicines, modern methods of immunotherapy of allergic diseases by recombinant medicines, as well as the issues of cell technology and tissue engineering. The review also describes the topics discussed at the 14th International Conference «High Medical Technologies of 21st Century» (October 24-31, 2015, Spain), related to fundamental and applied research, development and introduction of new technologies and modern medicines into clinical practice.

In 2009-2010 there was an influenza pandemic that occurred despite all preventive measures. Analysis of this pandemic revealed some gaps in the regulatory requirements applied both to the development of new influenza vaccines and to the change/update of the seasonal influenza vaccine strains. Taking into account the lessons learned from this pandemic the European Medicines Agency revised the existing guidelines in 2014-2016 and proposed new recommendations on quality evaluation and conduct of non-clinical and clinical trials in the development of influenza vaccines. The revised requirements encompass not only quality evaluation issues, but also changes/update of strain composition of seasonal, pre-pandemic and pandemic influenza vaccines. The experience acquired by the Agency can help update the Russian regulatory framework in order to improve efficacy and safety of influenza vaccines.

The review looks into various aspects of assessing specific activity of biotechnological products, which is one of their key quality parameters. Approaches to the analysis of this parameter and the choice of test procedures are governed by the nature and characteristics of a medicinal product. Test procedures should be adequate and have sufficient sensitivity and specificity. Specific activity of the products in question can be assessed by biological methods both in vivo using laboratory animals, which demonstrate the most adequate response to the tested product, and in vitro using sensitive cell lines. Assessment of specific biological activity helps to characterize the product’s pharmacological action and systematically examine the mechanisms of therapeutic effects in clinical practice. Therefore, specific activity of biotechnological products should be assessed using methods appropriate for the proposed mechanism of action. Many biotechnological products, such as cytokine system products, mAbs, fusion proteins and some others call for individual methods for assessment of their specific activity. Biotechnological products are successfully used in the treatment of autoimmune, infectious, oncological, and allergic diseases.