Measurement and characterization of subvisible particles (including proteinaceous and non-proteinaceous particulate matter) is an important aspect of the pharmaceutical development process for biotherapeutics. Health authorities have increased expectations for subvisible particle data beyond criteria specified in the pharmacopeia and covering a wider size range. In addition, subvisible particle data is being requested for samples exposed to various stress conditions and to support process/product changes.
View Article and Find Full Text PDFMeasurement and characterization of subvisible particles (defined here as those ranging in size from 2 to 100 μm), including proteinaceous and nonproteinaceous particles, is an important part of every stage of protein therapeutic development. The tools used and the ways in which the information generated is applied depends on the particular product development stage, the amount of material, and the time available for the analysis. In order to compare results across laboratories and products, it is important to harmonize nomenclature, experimental protocols, data analysis, and interpretation.
View Article and Find Full Text PDFOligosaccharides attached to Asn297 in each of the CH2 domains of monoclonal antibodies play an important role in antibody effector functions by modulating the affinity of interaction with Fc receptors displayed on cells of the innate immune system. Rapid, detailed, and quantitative N-glycan analysis is required at all stages of bioprocess development to ensure the safety and efficacy of the therapeutic. The high sample numbers generated during quality by design (QbD) and process analytical technology (PAT) create a demand for high-performance, high-throughput analytical technologies for comprehensive oligosaccharide analysis.
View Article and Find Full Text PDFPoly(ethylene glycol) (PEG)ylation of peptides and proteins creates significant challenges for detailed structural characterization, such as PEG heterogeneity, site of addition and number of attached PEGylated moieties. Recently, we published a novel LC/MS methodology with a post-column addition of amines to obtain accurate masses of PEGylated peptides and proteins. The accurate masses can be used to assign the structures and number of attached PEGs [15], but the PEGylation site remains unclear in situations where multiple potential attachments are involved.
View Article and Find Full Text PDFThe identification of antigenic epitopes is important for the optimization of monoclonal antibodies (mAbs) intended as therapeutic agents. MS has proven to be a powerful tool for the study of noncovalent molecular interactions such as those involved in antibody-antigen (Ab-Ag) binding. In this work, we described a novel methodology for mapping a linear epitope based on direct mass spectrometric measurement of Ab-Ag complexes.
View Article and Find Full Text PDFGlycosylation has been established as playing a pivotal role in various aspects of recombinant monoclonal antibodies (MAbs), ranging from pharmacokinetics to enhancement of effector function. Consequently, characterization of these oligosaccharides is of great importance and requires sensitive analytical techniques. Here we present a method for the rapid elucidation of 3-(acetylamino)-6-aminoacridine-labeled N-glycans present on MAbs using liquid chromatography-mass spectrometry.
View Article and Find Full Text PDFPEGylation of peptides and proteins presents significant challenges for structural characterization due to the heterogeneity of the poly(ethylene glycol) (PEG), the number of PEG moieties attached, and the site(s) of PEGylation. In this work, a novel and powerful methodology using a postcolumn addition combined with LC/MS was developed and applied to examine high molecular weight (>/=20 kDa) PEG as well as PEGylated peptide and protein products. The PEG and PEGylated compounds were eluted from RP-HPLC, and the HPLC stream was mixed with diethylmethylamine (DEMA) or triethylamine (TEA) through a T mixer coupled to a time-of-flight mass spectrometer.
View Article and Find Full Text PDFBackground: The stability of insulin lispro for use in continuous subcutaneous insulin infusion (CSII) therapy was evaluated using a stress test incorporating high temperature and mechanical agitation combined with simulated basal/bolus administration.
Methods: Insulin lispro formulation contained in MiniMed 507c (Medtronic MiniMed, Sylmar, CA), H-TRONplus (Disetronic Medical Systems, St. Paul, MN), and D-TRON CSII (Disetronic Medtronic Systems) devices was subjected to a stress test involving exposure to elevated temperature (37 degrees C) and mechanical agitation (shaking at 100 strokes/min) for 7 days.
Glucagon solutions at pH 2.0 were subjected to mechanical agitation at 37 degrees C in the presence of a hydrophobic surface to explore the details of aggregation and fiber formation. High-resolution intermittent-contact atomic force microscopy performed in solution revealed the presence of aggregates after 0.
View Article and Find Full Text PDFThe concept of comparability can be applied when changes are made to manufacturing processes for biotechnology products subsequent to pivotal clinical trial studies. For many process changes, comparability can be demonstrated based entirely on relevant in vitro data provided that a detailed knowledge of the process/product exists, suitable analytical methodology is employed, and historical data are available for the assessment. Insulin provides an excellent model system to illustrate many important considerations when dealing with comparability exercises for biotechnology products.
View Article and Find Full Text PDFInsulin was precipitated from solution in 1,1,1,3,3,3-hexafluoro-2-propanol (HFIP) using supercritical carbon dioxide (CO2) as an antisolvent. Biosynthetic human insulin crystals were dissolved in HFIP and the solution was sprayed through an ultrasonic nozzle into supercritical CO2. The factors in the 2(3) factorial experimental design with a center point replicate included pressure (83.
View Article and Find Full Text PDF