Publications by authors named "Thomas M Spitznagel"

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.

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Measurement 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.

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Reversed-phase high-performance liquid chromatography (RP-HPLC), which is routinely used to detect and quantitate levels of protein oxidation, was used to analyze a free cysteine-containing protein. However, the RP-HPLC method appeared to induce dimerization of the oxidized protein. The purpose of this study was to understand the role of RP-HPLC conditions in inducing protein dimerization.

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Silicone oil is often used to decrease glide forces in prefilled syringes and cartridges, common primary container closures for biopharmaceutical products. Silicone oil has been linked to inducing protein aggregation (Diabet Med 1989;6:278; Diabet Care 1987;10:786-790), leading to patient safety and immunogenicity concerns. Because of the silicone oil application process (Biotech Adv 2007;25:318-324), silicone oil levels tend to vary between individual container closures.

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An efficient freeze-dry cycle was developed for a high concentration monoclonal antibody formulation lacking a crystalline bulking agent. The formulation, at multiple protein concentrations, was characterized using differential scanning calorimetry (DSC) and freeze-dry microscopy. At low protein concentrations the glass transition temperature of the maximally freeze-concentrated solution (T(g)') determined by DSC was similar to the collapse temperature determined by freeze-dry microscopy.

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The interaction of several of the fibroblast growth factors (FGFs) with polyanions is thought to be of physiological significance and has been exploited to create more stable pharmaceutical formulations of FGF-1 and -2. The extent of such phenomena throughout the 23-member FGF family is, however, unknown. In these studies, we examine the effect of several polyanions on the structure and stability of keratinocyte growth factor 2 (KGF-2, FGF-10), a candidate for use as a wound-healing agent.

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Synopsis of recent research by authors named "Thomas M Spitznagel"

  • Dr. Thomas M. Spitznagel's research primarily focuses on the development and characterization of biotherapeutic drug products, particularly emphasizing the measurement and analysis of subvisible particles within this context.
  • His findings highlight the significance of harmonizing methodologies and protocols across laboratories to ensure reliable data interpretation and product safety.
  • Additionally, Spitznagel has investigated factors such as protein stability, the effects of conditions during analytical processes (like RP-HPLC), and the role of silicone oil in protein aggregation, contributing to the understanding of formulation challenges in biopharmaceuticals.