Improved sample introduction approach in hydrophilic interaction liquid chromatography to avoid breakthrough of proteins

When therapeutic proteins are analysed under hydrophilic interaction liquid chromatography (HILIC) conditions, there is an inherent mismatch between the sample diluent (proteins must be solubilised in aqueous media) and the mobile phase, which is mostly composed of aprotic solvent (acetonitrile). This difference in eluent strength between sample diluent and mobile phase is responsible for severe analyte breakthrough and peak distortion. As demonstrated with therapeutic proteins of different sizes (insulin of 6 kDa, anakinra of 17 kDa and rituximab subunits of 25 and 50 kDa), only very small volumes of 0.1–0.2 μL can be injected without breakthrough effects, when performing rapid analysis on short HILIC columns of 20–50 mm, leading to poor sensitivity. In order to avoid the undesired effect of the strong sample diluent, a special injection program should be preferred. This consists in the addition and automatic injection of a defined volume of weak solvent (acetonitrile) along with the sample to increase retention factors during sample loading. Various injection programs were tested, including the addition of a pre-injection or post-injection or both (bracketed injection) of acetonitrile plugs. Several weak to strong injection solvent ratios of 1:1, 1:2, 1:4 and 1:10 were tested. Our work proves that the addition of a pre-plug solvent with a weak vs. strong injection solvent ratio of 1:10 is a valuable strategy to inject relatively large volumes of proteins in HILIC, regardless of column dimensions, thus maximising sensitivity. No peak deformation or breakthrough was observed under these conditions. However, it is important to note that peak broadening (40 % larger peaks) was observed when the injection program increased the injection solvent ratio from 1:1 to 1:10. Finally, this strategy was applied to a wide range of therapeutic mAb products with different physico-chemical properties. In all cases, relatively large volumes can be successfully injected onto small volume HILIC columns using a purely aqueous sample diluent, as long as an appropriate (weak) solvent pre-injection is applied.Junta de Andalucía (ref: DOC_01694

Comprehensive Analysis of Nivolumab, A Therapeutic Anti-Pd-1 Monoclonal Antibody: Impact of Handling and Stress

This study was partially funded by Project P20-01029 (I+D+i-Junta de Andalucia, Spain) and by Project B-FQM-308-UGR20 (Universidad de Granada, Proyectos I+D+i del Programa Operativo FEDER Andalucia 2020) which means that it was also partially supported by European Regional Development Funds.Nivolumab, formulated in the medicine Opdivo (R) (10 mg/mL), is a therapeutic monoclonal antibody (mAb) used in the treatment of different types of cancer. Currently, there is insufficient knowledge about the behaviour of this protein with regards to the risk associated with its routine handling or unintentional mishandling, or when subjected to stress conditions in hospitals. These conditions can be simulated in forced degradation studies, which provide an in-depth understanding of the biophysical and biochemical properties of mAbs. In this study, we carried out a physicochemical and functional characterisation of nivolumab, which was subjected to various stress conditions: heat, freeze/thaw cycles, agitation, light exposure and high hypertonic solution. We used a wide range of analytical techniques: Far-UV CD, IT-FS, DLS, SE/UHPLC(UV)-[Native]MS, and ELISA. The results show that exposure to light was the stress test with the greatest impact on the samples, revelling the formation of non-natural dimers and a different isoform profile. In addition, nivolumab (Opdivo (R)) demonstrated stability up to 60 degrees C (1 h). As regards functionality all the nivolumab (Opdivo (R)) stressed samples were found to be stable except for those subjected to light and agitation, and to a lesser extent, those subjected to FTC 5 and NaCl stresses.I+D+i-Junta de Andalucia, Spain P20-01029European Commission B-FQM-308-UGR2

Stability study over time of clinical solutions of ziv-aflibercept prepared in infusion bags using a proper combination of physicochemical and functional strategies

The study was entirely funded by Project FIS: PI-17/00547(Instituto Carlos III, Ministerio de Economia y Competitividad, Spain), which means that it was also partially supported by European Regional Development Funds (ERDF).A range of biopharmaceutical products are used to target Vascular Endothelial Growth Factor (VEGF), including Eylea (R) (aflibercept, AFL) and Zaltrap (R) (ziv-aflibercept, ziv-AFL). The first is indicated for ophthalmological diseases such as neovascular (wet) age-related macular degeneration, while the second is used in the treatment of metastatic colorectal cancer. The stability of AFL in prefilled syringes has been widely studied; however, no research has yet been done on the stability of ziv-AFL in polyolefin infusion bags. Therefore, the purpose of the present research is to evaluate the stability of ziv-AFL (Zaltrap (R)) clinical solutions prepared under aseptic conditions in polyolefin infusion bags at two different concentrations, i.e. 4.0 and 0.6 mg/mL, and stored refrigerated in darkness at 2-8 degrees C for 14 days. With that aim, the ziv-AFL clinical solutions were assessed by analysing changes in its physicochemical and functional properties. The distribution of the particulates was studied over a range of 0.001-10 mu m by Dynamic Light Scattering (DLS); oligomers were analysed by Size-Exclusion High-Performance Chromatography with Diode Array Detection (SE/HLPC-DAD); the secondary structure of the protein was studied by far UV Circular Dichroism (CD) and the tertiary structure by Intrinsic Tryptophan Fluorescence (IT-F) and Intrinsic Protein Fluorescence (IP-F); charge variants were assessed by Strong Cation Exchange Ultra High-Performance Chromatography with UV detection (SCX/UHPLC-UV); functionality was evaluated by ELISA by measuring the biological activity as manifested in the extension of the immunological reaction of the ziv-AFL with its antigen (VEGF). Neither aggregation nor oligomerization were detected by the techniques mentioned above. Secondary and tertiary structures remained unchanged over the 14-day period, as did charge variants. The functionality observed initially was maintained along time. Therefore, it could be proposed that the ziv-AFL clinical solutions studied showed great physicochemical and functional stability over a period of two weeks, regardless of the concentration, i.e. 4 or 0.6 mg/mL.Project FIS (Instituto Carlos III, Ministerio de Economia y Competitividad, Spain) PI-17/00547European Commissio

The Relevance of Monoclonal Antibodies in the Treatment of COVID-19

This study was partially funded by Project FIS: PI-17/00547 (Institute of Health 'Carlos III', Ministry of Economy and Competitiveness, Spain), which means that it was also partially supported by European Regional Development Funds (ERDF).Major efforts have been made in the search for effective treatments since the outbreak of the COVID-19 infection in December 2019. Extensive research has been conducted on drugs that are already available and new treatments are also under development. Within this context, therapeutic monoclonal antibodies (mAbs) have been the subject of widespread investigation focusing on two target-based groups, i.e., non-SARS-CoV-2 specific mAbs, that target immune system responses, and SARS-CoV-2 specific mAbs, designed to neutralize the virus protein structure. Here we review the latest literature about the use of mAbs in order to describe the state of the art of the clinical trials and the benefits of using these biotherapeutics in the treatment of COVID-19. The clinical trials considered in the present review include both observational and randomized studies. We begin by presenting the studies conducted using non-SARS-CoV-2 specific mAbs for treating different immune disorders that were already on the market. Within this group of mAbs, we focus particularly on anti-IL-6/IL-6R. This is followed by a discussion of the studies on SARS-CoV-2 specific mAbs. Our findings indicate that SARS-CoV-2 specific mAbs are significantly more effective than non-specific ones.Institute of Health 'Carlos III', Ministry of Economy and Competitiveness, Spain - European Regional Development Funds (ERDF) FIS: PI-17/0054

Degradation and in-use stability study of five marketed therapeutic monoclonal antibodies by generic weak cation exchange liquid chromatographic method ((WCX)HPLC/DAD)

Therapeutic monoclonal antibodies (mAbs) represent a very important class of the current biopharmaceutics. The great complexity of their structure made necessary the use of different analytical approaches for assessing different physico-chemical properties. In this work, weak cation exchange (WCX) high performance liquid chromatography with diode array detection ((WCX)HPLC/DAD) is used to assess the charge variant profile. The method here developed combined the effect of ionic strength and controlled pH gradient and allows for the charge variants analysis of the five mAbs studied, namely bevacizumab (BVZ), cetuximab (CTX) infliximab (INF), rituximab (RTX) and trastuzumab (TTZ), which are among the most used mAbs worldwide. The differences in the charge variants in the natural isoforms of the mAbs promoted characteristic WCX chromatograms for each of mAbs that can be also useful for identification purposes. These chromatograms have provided to be suitable for tracking changes in the charge variants of each mAb analyzed both in controlled degraded and in stabilities study along time of in-use samples solutions at 2 mg/mL in 0.9% NaCl stored refrigerated (at 4 ?C) and frozen (-20 ?C) for two months. The results obtained indicated different stabilities of these mAbs, all IgG1, against degradation by different stressed environmental conditions and in-use stability along two months.Instituto Carlos III, Ministerio de Economia y Competitividad, Spain FIS-PI10/00201 FIS-PI17/00547European Commission Junta de Andalucia European Commissio

Combined use of UV and MS data for ICH Stability-Indication Method: Quantification and isoforms identification of intact nivolumab

Nivolumab (Opdivo®) is a fully human immunoglobulin G4 isotype approved for the treatment of many cancers. It acts as an immune checkpoint inhibitor by blocking the interaction between PD-1 (Programmed Cell Death Protein 1) – an inhibitory receptor expressed on activated T cells- and its ligands, PD-L1 and PD-L2. The quantification of therapeutic proteins in their medicines and pharmaceutical preparations remains challenging because the protein content, a critical quality attribute, must be rigorously calculated using a validated stabilityindicating method, such as that indicated by the International Conference on Harmonization (ICH) quality guidelines, and this requires the analysis of the drug in the presence of its degraded products. In this work, we present an strategy based on the combined use of the UV and MS data to full file the requirement of the ICH-Q2 (R1) to develop and validated as stability indicated a (RP)UHPLC/UV-(HESI/Orbitrap™)MS method for the quantification of nivolumab in medicinal products. A comparative study of all figures of merit of the method using UV or MS data are shown and discussed. The results show that linearity was similar for the two detectors and was established over a range of 4–45 μg/mL and 1–45 μg/mL for the UV and (HESI/Orbitrap™)MS signals, respectively. The sensitivity of the method was higher when using the (HESI/Orbitrap™)MS signal (0.2 μg/mL) than with the UV(2.0 μg/mL). However, the UV signal provided better accuracy and precision than the (HESI/ Orbitrap™)MS signal, which did not meet the criteria for method robustness and system suitability. In spite of this, the MS signal plays a crucial role in this methodology by obtaining the molecular weight profile of the nivolumab isoforms, so enabling us to propose the glycans profile and detect structural modification due to degradation. The specificity of the method was evaluated by conducting forced degradation tests on samples of nivolumab in medicine form. The aim was to find out whether nivolumab suffers structural modifications when subject to stress. Structural modifications were detected by analysing the MS isoform profile, as changes of this kind promote new isoforms that are not chromatographically separated or detected by the UV signal. In this way, we demonstrated that the (RP)UHPLC/UV-(HESI/Orbitrap™)MS method was capable of detecting nivolumab degradation, and was suitable for use in nivolumab stability studies. Thus, the protein content in the daily surplus of the Opdivo® medicine, stored either at room temperature (20 ◦C) or refrigerated at 4 ◦C, could be tracked for 15 days.FPU18/03131 Ministry of Universities, Spain(P20_01029) Junta de Andalucía (Spain) and European Regional Development Fundspostdoctoral position from the Junta de Andalucía, SpainProject P20-01029 (I + D + i - Junta de Andalucía, Spain) Project B-FQM-308-UGR20 (Universidad de Granada, Proyectos I + D + i del Programa Operativo FEDER Andalucía 2020)CBUA/ Universidad de Granad

Comprehensive biophysical and functional study of ziv-aflibercept: characterization and forced degradation

This study was entirely funded by Project FIS: PI-17/00547 (Instituto Carlos III, Ministerio de Economia y Competitividad, Spain), which means that it was also partially supported by European Regional Development Funds (ERDF).Aflibercept (AFL) is an Fc fusion protein used in the treatment of colorectal cancers and different ophthalmological diseases. There are two medicines in which AFL is the active substance: Zaltrap and Eylea, referred as ziv-AFL and AFL respectively. No proper accelerated degradation studies were published on either AFL or ziv-AFL. These studies are essential during research, development and manufacturing stages. Here, we characterized ziv-AFL and submitted it to different stress conditions: light, 60 °C, freeze-thaw cycles, changes in pH, high hypertonic solution and strong denaturing conditions. We used an array of techniques to detect aggregation (SE-HPLC/DAD and DLS), changes in secondary structure (Far-UV circular dichroism), changes in conformation or tertiary structure (Intrinsic tryptophan fluorescence) and alterations in functionality (ELISA). Results indicate that aggregation is common degradation pathway. Two different types of aggregates were detected: dimers and high molecular weight aggregates attributed to β-amyloid-like structures. Secondary structure was maintained in most of the stress tests, while conformation was altered by almost all the tests except for the freeze-thaw cycles. Functionality, evaluated by its immunochemical reaction with VEGF, was found to be stable but with decrease when exposed to light and with likely partial inactivation of the drug when pH was altered.European Union (EU) FIS: PI-17/0054

Separation and Determination of Some of the Main Cholesterol-Related Compounds in Blood by Gas Chromatography-Mass Spectrometry (Selected Ion Monitoring Mode)

Oxysterols are metabolites produced in the first step of cholesterol metabolism, which is related to neurodegenerative disorder. They can be detected by testing blood, plasma, serum, or cerebrospinal fluid. In this study, some cholesterol precursors and oxysterols were determined by gas chromatography coupled to mass spectrometry. The selected cholesterol-related compounds were desmosterol, lathosterol, lanosterol, 7 -hydroxycholesterol, 7 -hydroxycholesterol, 24(S)-hydroxycholesterol, 25-hydroxycholesterol, 7-ketocholesterol, and 27-hydroxycholesterol. A powerful method was developed and validated considering various analytical parameters, such as linearity index, detection and quantification limits, selectivity and matrix effect, precision (repeatability), and trueness (recovery factor) for each cholesterol-related compound. 7 -hydroxycholesterol, 7 -hydroxycholesterol, and desmosterol exhibited the lowest detection and quantification limits, with 0.01 and 0.03 g/mL, respectively, in the three cases. 7-ketocholesterol and lathosterol showed matrix effect percentages between 95.5% and 104.8%, respectively (demonstrating a negligible matrix effect), and very satisfactory repeatability values (i.e., overall performance of the method). Next, the method was applied to the analysis of a very interesting selection of mouse plasma samples (9 plasma extracts of non-transgenic and transgenic mice that had been fed different diets). Although the number of samples was limited, the current study led to some biologically relevant conclusions regarding brain cholesterol metabolism.The authors are grateful for the interesting collaboration with the biotechnology-based company Neuron Bio. The research project was funded by CEI BioTic/University of Granad

Method for identification and quantification of intact teduglutide peptide using (RP)UHPLC-UV- (HESI/ORBITRAP)MS

Teduglutide (Revestive®, 10 mg mL−1) is a recombinant human glucagon-like peptide 2 analogue, used in the treatment of short bowel syndrome, a serious and highly disabling condition which results from either too small a length of intestine or loss of critical intestinal function. The determination of therapeutic compounds of protein-nature is always challenging due to their complex structure. In this work, we present a fast, straightforward reversed phase (RP)UHPLC-UV-(HESI/ORBITRAP)MS method for the identification and quantification of the intact teduglutide peptide. The method has been developed and validated in accordance with the International Council for Harmonization of Technical Requirements for Pharmaceuticals for Human Use (ICH) guidelines; therefore, linearity, limits of detection and quantification, accuracy (precision and trueness), robustness, system suitability and specificity using the signal from the UV and MS, have been evaluated. The validation performance parameters obtained from the UV and MS signals were compared throughout the work, to select the most suitable. To study the specificity of the method and the impact of medicine mishandling under hospital conditions, force degradation studies were performed, i.e. thermal (40 °C and 60 °C), shaking (mechanical) and light (accelerated exposition) effects. Identification by the exact mass of teduglutide was achieved and it was confirmed that the peptide does not undergo any post-translational modifications (PTMs). To the best of our knowledge, the present work reports the first method developed for the simultaneous identification, structural characterization, and quantification of the therapeutic teduglutide peptide. Finally, the proposed method is able to indicate stability when quantifying the intact teduglutide since detects and characterises the exact mass of the degradation/modification products.Fundacion Andaluza de Farmacia Hospitalaria (Spain) TEC01 FQM 118Junta de Andalucia DOC_01694Hospital Paediatrics Pharmacy Unit of the Hospital Vall d' Hebron (Barcelona, Spain