Risk Management Plan and Pharmacovigilance System. Biopharmaceuticals: Biosimilars

Editor literario del libro, Giancarlo Nota - All chapters are Open Access articles distributed under the Creative Commons Non Commercial-Share Alike-Attribution 3.0 license, which permits to copy, distribute, transmit, and adapt the work in any medium, so long as the original work is properly cited

Evaluación de la biosimilitud y comparabilidad de medicamentos biosimilares

Al finalizar el periodo de patente de los medicamentos de origen biotecnológico, como las proteínas de origen recombinante y los anticuerpos monoclonales, se ha abierto la posibilidad de fabricar copias de dichos fármacos, denominados medicamentos biosimilares. Para conseguir la aprobación de estos fármacos no es aplicable el marco legal existente para los genéricos, ya que los biosimilares son productos similares pero no idénticos al medicamento innovador. El fabricante del medicamento biosimilar debe demostrar que su producto es tan seguro y eficaz como el medicamento original (medicamento de referencia). Esta demostración se lleva a cabo mediante el denominado “ejercicio de comparabilidad o de biosimilitud”, que incluye la caracterización analítica de ambos productos (medicamento original y biosimilar), así como los estudios de estabilidad y estudios preclínicos y clínicos que permitan realizar una evaluación de las propiedades farmacocinéticas, farmacodinámicas e inmunogénicas del medicamento biosimilar, además de los estudios de eficacia y seguridad.Some biotechnology-derived medicines (e.g. therapeutic proteins and monoclonal antibodies) patents have expired allowing the so-called biosimilars hit the market. As biosimilars are similar but not identical to the innovator product the existing legal framework for generic drugs does not apply. The applicant of a biosimilar marketing authorization must demonstrate that its product is as safe and effective as the innovator product (reference product). This comparison is performed by means of a “biosimilarity /comparability exercise”, which includes analytical characterization of both products (innovator and biosimilar), stability studies and preclinical and clinical studies to determine the pharmacokinetics, pharmacodynamic and immunogenic evaluation of the biosimilar medicine. Efficacy and safety studies are also required

Biosimilar products: evaluation of biosimilarity and comparability

Al finalizar el periodo de patente de los medicamentos de origen biotecnológico, como las proteínas de origen recombinante y los anticuerpos monoclonales, se ha abierto la posibilidad de fabricar copias de dichos fármacos, denominados medicamentos biosimilares. Para conseguir la aprobación de estos fármacos no es aplicable el marco legal existente para los genéricos, ya que los biosimilares son productos similares pero no idénticos al medicamento innovador.El fabricante del medicamento biosimilar debe demostrar que su producto es tan seguro y eficaz como el medicamento original (medicamento de referencia). Esta demostración se lleva a cabo mediante el denominado “ejercicio de comparabilidad o de biosimilitud”, que incluye la caracterización analítica de ambos productos (medicamento original y biosimilar), así como los estudios de estabilidad y estudios preclínicos y clínicos que permitan realizar una evaluación de las propiedades farmacocinéticas, farmacodinámicas e inmunogénicas del medicamento biosimilar, además de los estudios de eficacia y seguridad.Some biotechnology-derived medicines (e.g. therapeutic proteins and monoclonal antibodies) patents have expired allowing the so-called biosimilars hit the market. As biosimilars are similar but not identical to the innovator product the existing legal framework for generic drugs does not apply.The applicant of a biosimilar marketing authorization must demonstrate that its product is as safe and effective as the innovator product (reference product). This comparison is performed by means of a “biosimilarity /comparability exercise”, which includes analytical characterization of both products (innovator and biosimilar), stability studies and preclinical and clinical studies to determine the pharmacokinetics, pharmacodynamic and immunogenic evaluation of the biosimilar medicine. Efficacy and safety studies are also required

Risk management plan and pharmacovigilance system - biopharmaceuticals: biosimilars.

Editor literario del libro, Giancarlo Nota - All chapters are Open Access articles distributed under the Creative Commons Non Commercial-Share Alike-Attribution 3.0 license, which permits to copy, distribute, transmit, and adapt the work in any medium, so long as the original work is properly cited

Biosimilars – the way forward

Biotechnology represents a considerable opportunity, but also a challenge, given the complexities and risk associated with the development and manufacture of biological medicines

Relation between the lipid composition of Brucella membrane and the resistance to cationic peptides

Póster presentado en el Annual Meeting of the German Biophysical Society, celebrado en Göttingen (Alemania) del 23 al 26 de septiembre de 2012.The members of the genus Brucella are α-2 Proteobacteria that cause brucellosis, an important zoonosis. These bacteria trigger only low proinflammatory responses during early infection that allows them to reach sheltered intracellular niches before effective immunity activation. The outer membranes (OM) of brucellae are of critical importance in this strategy. The OM of B. abortus is unusually resistant to antimicrobial peptides (AMPs). Brucella lipopolysaccharide (LPS) is implicated in this property and there is evidence that other lipids (such as phosphatidylcholine) also contribute. Furthermore, these bacteria have acyl chains of average number of carbon units which leads an increase in hydrophobicity, proposed as a biophysical factor underlining AMPs resistance.Peer reviewe

Brucella abortus depends on pyruvate phosphate dikinase and malic enzyme but not on Fbp and GlpX fructose-1,6-bisphosphatases for full virulence in laboratory models

Póster presentado en el 2nd International Symposium on Metabolism and Bacterial Pathogenesis, celebrado en Osnabrück (Alemania), del 6 al 9 de abril de 2014.Brucellosis is a disease of terrestrial and marine mammals and an important zoonosis. The ability of brucellae to multiply intracellularly in a variety of cells is the cornerstone of the biology of this pathogen and requires both controlling the intracellular trafficking and using the nutrients available in the replicative niche. The main carbon substrates used intracellularly for biosynthesis and energy production by Brucella are not known, and a better understanding of the adaptation to host cell nutrient supply is required.This work was funded by grants from Friends of the University of Navarra, Gobierno de Navarra, Ministerio de Ciencia y Tecnología (Spain), Institute of Tropical Health (University of Navarra) and UNAmur (Belgium)Peer Reviewe

Identification and functional analysis of the cyclopropane fatty acid synthase of Brucella abortus

The brucellae are facultative intracellular pathogens of mammals that are transmitted by contact with infected animals or contaminated materials. Several major lipidic components of the brucella cell envelope are imperfectly recognized by innate immunity, thus contributing to virulence. These components carry large proportions of acyl chains of lactobacillic acid, a long chain cyclopropane fatty acid (CFA). CFAs result from addition of a methylene group to unsaturated acyl chains and contribute to resistance to acidity, dryness and high osmolarity in many bacteria and to virulence in mycobacteria. We examined the role of lactobacillic acid in Brucella abortus virulence by creating a mutant in ORF BAB1_0476, the putative CFA synthase gene. The mutant did not incorporate [ 14C]methyl groups into lipids, lacked CFAs and synthesized the unsaturated precursors, proving that BAB1_0476 actually encodes a CFA synthase. BAB1_0476 promoter-luxAB fusion studies showed that CFA synthase expression was promoted by acid pH and high osmolarity. The mutant was not attenuated in macrophages or mice, strongly suggesting that CFAs are not essential for B. abortus intracellular life. However, when the mutant was tested under high osmolarity on agar and acid pH, two conditions likely to occur on contaminated materials and fomites, they showed reduced ability to grow or survive. Since CFA synthesis entails high ATP expenses and brucellae produce large proportions of lactobacillic acyl chains, we speculate that the CFA synthase has been conserved because it is useful for survival extracellularly, thus facilitating persistence in contaminated materials and transmission to new hosts.Peer Reviewe

Study on the Role of Brucella Membrane Lipids in the Resistance to Antimicrobial Peptides. Is this membrane particular?

Trabajo presentado en el XIII International Congress of the Spanish Biophysical Society, celebrado en Valencia (España) del 19 al 21 de junio de 2013.The interactions between antimicrobial peptides (AMPs) and lipid membranes can be studied in detail by using reconstituted lipid membranes. Up to now, most of these studies used well defined synthetic or purified phospholipids. However, investigations using purified total lipids from Gram- negative bacteria are limited. Although classical Gram negative bacteria (i.e. the Proteobacteria ) are the most diverse prokaryotic group, the activity of AMPs on Gram-negative membranes has been mainly concentrated on a few genus of the g - Proteobacteria division (e.g., Salmonella , Proteus , Escherichia, or Pseudomonas ) that are relatively sensitive to AMPs. The members of the genus Brucella are α - Proteobacteria that cause brucellosis, an important zoonosis. These bacteria are imperfectly detected by the innate immune system. The outer membrane of brucellae is of critical importance in this strategy. In addition to the lipopolysaccharide, other lipid molecules contribute to this process. The presence of phosphatidylcholine, aminolipids and long acyl chains are bio - physical factors underlining AMPs resistance and pathogenicity in these bacteria. Considering the hypothesis that the lipid and peptide specific properties are responsible for differential sensitivity or resistance of bacteria, the purposes are 1) to better understand the interaction between AMPs and bacterial membranes and, 2) to determine whether the lipid composition of the membranes drives to differential behaviour and resistance among the Proteobacteria members. Minimum Inhibitory Concentrations (MIC) were determined by the broth microdilution test in Mu - eller-Hinton medium. Fourier-Transform Infrared Spectroscopy (FTIR) was performed to test the influence of peptides on the gel to liquid crystalline phase behaviour of modelling membranes. Fluorescence Resonance Energy Transfer Spectroscopy (FRET) was used to study the peptide intercalation into the membranes. A method based on nanochips was applied to determine the permeabilization of the membrane. Lipids from different strains were extracted using the protocol described by Bligh and Dyer (1959). Different MIC values were observed depending on the strain, being Brucella the most resistant one. Using the lipid reconstituted membranes, we observed differences in the fluidity and phase transition temperature (Tc), even without the addition of peptides. In contrast to Proteus , Salmo - nella and E.coli which had a very marked Tc, 30°- 35°C, that of Brucella was around 25°C. This indicated a completely different membrane behaviour and, consequently it would lead to diverse ways of lipid- peptide interaction. FRET experiments showed that, in the case of Brucella, more peptide can intercalate into the membrane, in contrast to the sensitive strains. In conclusion, the connection between the biological and biophysical data allowed us to use these models to exam - ine the role of purified total lipids in the sensitivity/ resistance of bacteria. Moreover, the fact that Brucella membrane presented particularities, could be the starting point to investigate a model of intrinsic resistance that has not been explored thus far, being applicable to other pathogens of the α - Proteobacteria class, including Bartonella , Rickettsia , Ehrlichia and Anaplasma .Peer Reviewe