Adeno-associated viruses (AAVs) have emerged as a promising gene delivery vehicle for the treatment of diseases. As AAVs are a complex therapeutic modality, new analytical techniques are needed to thoroughly characterize the critical quality attributes (CQAs) to support drug development. Empty and full ratio is one of the CQAs of AAVs that may impact drug safety and efficacy.
View Article and Find Full Text PDFMessenger RNA (mRNA) is rapidly growing as a therapeutic modality for vaccination and the treatment of a wide range of diseases. As a result, there is an increased demand for mRNA-based analytical methods capable of assessing purity and stability, which are considered critical quality attributes (CQAs). In recent decades capillary electrophoresis (CE) has emerged alongside liquid chromatography (LC) as an important tool for the assessment of purity and stability of mRNA therapeutics.
View Article and Find Full Text PDFHeightened interest in messenger RNA (mRNA) therapeutics has accelerated the need for analytical methodologies that facilitate the production of supplies for clinical trials. Forced degradation studies are routinely conducted to provide an understanding of potential weak spots in the molecule that are exploited by stresses encountered during bulk purification, production, shipment, and storage. Consequently, temperature fluctuations and excursions are often experienced during these unit operations and may accelerate mRNA degradation.
View Article and Find Full Text PDFCo-formulation of multiple drug products is an efficient and convenient approach to simultaneously deliver multiple biotherapeutics with the potentially added benefit of a synergistic therapeutic effect. However, co-formulation also increases the risk of heteromeric interactions, giving rise to unique impurities with unknown efficacy and immunogenicity. Therefore, it is critical to develop methods to evaluate the risk of heteromers as an impurity that could affect potency, efficacy, and/or immunogenicity.
View Article and Find Full Text PDFCharge heterogeneity is inherent to all therapeutic antibodies and arises from post-translational modifications (PTMs) and/or protein degradation events that may occur during manufacturing. Among therapeutic antibodies, the bispecific antibody (bsAb) containing two unique Fab arms directed against two different targets presents an additional layer of complexity to the charge profile. In the context of a bsAb, a single domain-specific PTM within one of the Fab domains may be sufficient to compromise target binding and could potentially impact the stability, safety, potency, and efficacy of the drug product.
View Article and Find Full Text PDFThe 3' poly(A) tail is an important component of messenger RNA (mRNA). The length of the poly(A) tail has direct impact on the stability and translation efficiency of the mRNA molecule and is therefore considered to be a critical quality attribute (CQA) of mRNA-based therapeutics and vaccines. Various analytical methods have been developed to monitor this CQA.
View Article and Find Full Text PDFTherapeutic antibodies are a major class of pharmaceutical drugs used to treat a wide variety of diseases. They have several advantages including the high specificity and binding affinity to their molecular targets, and generally low immunotoxicity and mild adverse effects. The characterization of therapeutic antibodies is crucial to ensure drug efficacy and safety.
View Article and Find Full Text PDFOver seventy percent of marketed monoclonal antibody therapeutics contain between 0.001% and 0.1% (w/v) polysorbate, as it has a generally beneficial stabilizing effect that increases drug product shelf life.
View Article and Find Full Text PDFHigh concentration formulations of therapeutic monoclonal antibodies (mAbs) are highly desired for subcutaneous injection. However, high concentration formulations can exhibit unusual molecular behaviors, such as high viscosity or aggregation, that present challenges for manufacturing and administration. To understand the molecular mechanism of the high viscosity exhibited by high concentration protein formulations, we analyzed a human IgG4 (mAb1) at high protein concentrations using sedimentation velocity analytical ultracentrifugation (SV-AUC), X-ray crystallography, hydrogen/deuterium exchange mass spectrometry (HDX-MS), and protein surface patches analysis.
View Article and Find Full Text PDFUnlabelled: Pharmacological inhibition of VEGF-A has proven to be effective in inhibiting angiogenesis and vascular leak associated with cancers and various eye diseases. However, little information is currently available on the binding kinetics and relative biological activity of various VEGF inhibitors. Therefore, we have evaluated the binding kinetics of two anti-VEGF antibodies, ranibizumab and bevacizumab, and VEGF Trap (also known as aflibercept), a novel type of soluble decoy receptor, with substantially higher affinity than conventional soluble VEGF receptors.
View Article and Find Full Text PDFVEGF is the best characterized mediator of tumor angiogenesis. Anti-VEGF agents have recently demonstrated impressive efficacy in human cancer trials, but the optimal dosing of such agents must still be determined empirically, because biomarkers to guide dosing have yet to be established. The widely accepted (but unverified) assumption that VEGF production is quite low in normal adults led to the notion that increased systemic VEGF levels might quantitatively reflect tumor mass and angiogenic activity.
View Article and Find Full Text PDFCytokines can initiate and perpetuate human diseases, and are among the best-validated of therapeutic targets. Cytokines can be blocked by the use of soluble receptors; however, the use of this approach for cytokines such as interleukin (IL)-1, IL-4, IL-6 and IL-13 that use multi-component receptor systems is limited because monomeric soluble receptors generally exhibit low affinity or function as agonists. We describe here a generally applicable method to create very high-affinity blockers called 'cytokine traps' consisting of fusions between the constant region of IgG and the extracellular domains of two distinct cytokine receptor components involved in binding the cytokine.
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