Biologic products encounter various types of interfacial stress during development, manufacturing, and clinical administration. When proteins come in contact with vapor–liquid, solid–liquid, and liquid–liquid surfaces, these interfaces can significantly impact the protein drug product quality attributes, including formation of visible particles, subvisible particles, or soluble aggregates, or changes in target protein concentration due to adsorption of the molecule to various interfaces. Protein aggregation at interfaces is often accompanied by changes in conformation, as proteins modify their higher order structure in response to interfacial stresses such as hydrophobicity, charge, and mechanical stress. Formation of aggregates may elicit immunogenicity concerns; therefore, it is important to minimize opportunities for aggregation by performing a systematic evaluation of interfacial stress throughout the product development cycle and to develop appropriate mitigation strategies. The purpose of this white paper is to provide an understanding of protein interfacial stability, explore methods to understand interfacial behavior of proteins, then describe current industry approaches to address interfacial stability concerns. Specifically, we will discuss interfacial stresses to which proteins are exposed from drug substance manufacture through clinical administration, as well as the analytical techniques used to evaluate the resulting impact on the stability of the protein. A high-level mechanistic understanding of the relationship between interfacial stress and aggregation will be introduced, as well as some novel techniques for measuring and better understanding the interfacial behavior of proteins. Finally, some best practices in the evaluation and minimization of interfacial stress will be recommended.
Aqueous solutions of > or =5% glutaraldehyde (GA) are of moderate acute peroral toxicity and those of < or =2% are of slight toxicity. By single sustained skin contact, aqueous GA solutions of > or =45% are of moderate acute percutaneous toxicity, those of 25% are of slight toxicity and those of =15% do not present an acute percutaneous hazard. Vapor generated at ambient temperature may cause sensory irritant effects to the eye and respiratory tract, but not acute respiratory tract injury. The 50% decrease in respiratory rate (rd(50)) is 13.86 ppm. A 0.1% solution of GA is not irritating to the eye; the threshold for conjunctival irritation is 0.2% and for corneal injury it is 1.0%. Eye injury is moderate at 2% and severe at > or =5%. Primary skin irritation depends on the duration and contact site, occlusion and solvent. By sustained contact, the threshold for skin irritation is 1%, above which erythema and edema are dose related. With 45% and higher, skin corrosion may occur. There is a low incidence of skin sensitizing reactions, with an eliciting threshold of 0.5% aqueous GA. However, GA is neither phototoxic nor photosensitizing. Subchronic repeated exposure studies by the peroral route show only renal physiological compensatory effects, secondary to reduced water consumption. Repeated skin contact shows only minor skin irritant effects without systemic toxicity. By subchronic vapor exposure, effects are limited to the nasal mucosa at 1.0 ppm, with a no-effect concentration generally at 0.1 ppm. There is no evidence for systemic target organ or tissue toxicity by subchronic repeated exposure by any route. A chronic drinking water study showed an apparent increase, in females only, of large granular cell lymphocytic leukemia but this was not dosage related. This is most likely the result of a modifying effect on the factor(s) responsible for the expression of this commonly occurring rat neoplasm. A chronic (2-year) inhalation toxicity/oncogenicity study showed inflammatory changes in the anterior nasal cavity but no neoplasms or systemic toxicity. In vitro genotoxicity studies--bacterial mutagenicity, forward gene mutation (HGPRT and TK loci), sister chromatid exchange, chromosome aberration, UDS and DNA repair tests--have given variable results, ranging from no effect through to weak positive. In vivo genotoxicity studies--micronucleus, chromosome aberration, dominant lethal and Drosophila tests--generally have shown no activity but one mouse intraperitoneal study showed bone marrow cell chromosome aberrations. Developmental toxicity studies show GA not to be teratogenic, and a two-generation study showed no adverse reproductive effects. Percutaneous pharmacokinetic studies showed low skin penetration, with lowest values measured in vitro in rats and human skin. Overexposure of humans produces typical sensory irritant effects on the eye, skin and respiratory tract. Some reports have described an asthmatic-like reaction by overexposure to GA vapor. In most cases this resembles reactive airways dysfunction s...
To improve liquid formulation stability, formulators employ various excipients designed to stabilize protein drugs, including buffers, salts, sugars, and surfactants. One of the roles of surfactants is to protect the protein drug from surface interactions that can destabilize the protein. Protein drug products formulated with surfactants usually contain either a polysorbate or poloxamer. Even in the presence of these surfactants, protein drug stability is often insufficient, particularly because of agitation-induced aggregation. FM1000 is one of a series of surfactants containing an alkyl chain, an amino acid, and a polyetheramine. The characterization of the dynamics of FM1000 at various water/hydrophobic interfaces was compared to Polysorbate 20, Polysorbate 80, and Poloxamer 188. FM1000 stabilizes an interface 1−2 orders of magnitude faster than all three of these surfactants, even in the presence of protein. The faster dynamics leads to improved stabilization of model protein biologic drugs IgG and abatacept against agitation-induced aggregation. These results provide mechanistic understanding of the key causes and drivers of protein aggregation.
With the rapid development of protein-based pharmaceutical products over the past decade, one of the biggest challenges in product development is maintaining the structural stability of proteins during purification, processing, and storage. In this work, the design of a new class of surfactants, polyethermodified N-acyl amino acids, is presented. One surfactant from this series, containing a phenylalanine moiety, demonstrated remarkable stabilization against aggregation of several model protein drugs. Dynamic light scattering, size exclusion chromatography, and circular dichroism all show the rate of thermally accelerated protein aggregation slowed. IgG aggregation was reduced by 3-fold compared to polysorbate controls. Testing of Orencia, a prescription biologic drug for rheumatoid arthritis, demonstrated a 36% improvement in monomer retention upon heat-aging.
The microbiocidal activity of glutaraldehyde was inactivated by reaction with sodium bisulfite via formation of a proposed glutaraldehyde-bisulfite complex. High-performance liquid chromatography (HPLC) analysis of 2% (0.2M) alkaline glutaraldehyde indicated complete loss of glutaraldehyde at a 2.2:1 molar ratio of sodium bisulfite to glutaraldehyde. Neither 1.7% (0.17 M) sodium bisulfite alone nor the glutaraldehyde-bisulfite complex was microbiocidal when tested against Escherichia coli, Pseudomonas aeruginosa, Enterobacter aerogenes, and Polybac Polyseed BOD seed inoculum. Bacterial inhibition tests indicated that the glutaraldehyde-sodium bisulfite complex had no effect on the growth of sewage microorganisms at concentrations as high as 50-100 ppm (5 x 10(-4)-1 x 10(-3) M), with an IC50 of 230-440 ppm (2.3 x 10(-3)-4.4 x 10(-3) M), based on glutaraldehyde concentration. A 28-close bottle test showed a 5-d biodegradation of 48% and 51%, and a 15-d biodegradation of 57% and 63% for 3:1 and 2.2:1 bisulfite to glutaraldehyde molar ratios, respectively. Acute aquatic toxicity testing with Daphnia magna demonstrated an LC50 of 41-109 ppm (4.1 x 10(-4)-10.9 x 10(-4) M) and a no-observed-effect concentration (NOEC) of 16 ppm (1.6 x 10(-4) M) for the proposed glutaraldehyde-bisulfite complex (based on glutaraldehyde concentration), approximately 10-fold higher than found for glutaraldehyde alone, indicating that the proposed glutaraldehyde-bisulfite complex is less toxic to the environment than glutaraldehyde.
The feasibility of various cellulose polymer derivatives, including methylcellulose (MC), hydroxypropyl methylcellulose (HPMC), sodium-carboxymethylcellulose (sodium-CMC), and cationic-hydroxyethylcellulose (cationic-HEC), for use as an excipient to enhance drug delivery in nasal spray formulations was investigated. Three main parameters for evaluating the polymers in nasal drug delivery applications include rheology, ciliary beat frequency (CBF), and permeation across nasal tissue. Reversible thermally induced viscosity enhancement was observed at near nasal physiological temperature when cellulose derivatives were combined with an additional excipient, poly(vinyl caprolactam)-poly(vinyl acetate)-poly(ethylene glycol) graft copolymer (PVCL-PVA-PEG). Cationic-HEC was shown to enhance acyclovir permeation across the nasal mucosa. None of the tested cellulosic polymers caused any adverse effects on porcine nasal tissues and cells, as assessed by alterations in CBF. Upon an increase in polymer concentration, a reduction in CBF was observed when ciliated cells were immersed in the polymer solution, and this decrease returned to baseline when the polymer was removed. While each cellulose derivative exhibited unique advantages for nasal drug delivery applications, none stood out on their own to improve more than one of the performance characteristics examined. Hence, these data may be useful for the development of new cellulose derivatives in nasal drug formulations.
Our ability to make scientific progress is dependent upon our interpretation of data. Thus, analyzing only those data that are an honest representation of a sample is imperative for drawing accurate conclusions that allow for robust, generalizable, and replicable scientific findings. Unfortunately, a consistent line of evidence indicates the presence of inattentive/careless responders who provide low-quality data in surveys, especially on popular online crowdsourcing platforms such as Amazon’s Mechanical Turk (MTurk). Yet, the majority of psychological studies using surveys only conduct outlier detection analyses to remove problematic data. Without carefully examining the possibility of low-quality data in a sample, researchers risk promoting inaccurate conclusions that interfere with scientific progress. Given that knowledge about data screening methods and optimal online data collection procedures are scattered across disparate disciplines, the dearth of psychological studies using more rigorous methodologies to prevent and detect low-quality data is likely due to inconvenience, not maleficence. Thus, this review provides up-to-date recommendations for best practices in collecting online data and data screening methods. In addition, this article includes resources for worked examples for each screening method, a collection of recommended measures, and a preregistration template for implementing these recommendations.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.