Optimization of continuous spin-freeze-drying: The role of spin-freezing on quality attributes and drying efficiency of a model peptide formulation.

Continuous spin-freeze-drying is an innovative pharmaceutical manufacturing approach offering real-time monitoring and control at the individual vial level, unlike conventional batch lyophilization. A central feature of this technology is spin-freezing, which involves rapidly spinning liquid-filled vials under a precisely controlled cold gas flow, resulting in a thin, uniform frozen product layer. Using a model peptide formulation, we investigated the impact of different cooling and crystallization rates on quality attributes (QA) and primary drying duration.

Impact of pneumatic tube transportation on the aggregation of monoclonal antibodies in clinical practice.

Postproduction handling and in-hospital transportation of antibody drugs cause mechanical stress, including interfacial and shear stress, that can induce antibody unfolding and aggregation. The handling practices differ significantly between hospitals and the impact on protein stability is unknown. For example, the mechanical stress caused by transport via pneumatic tube systems (PTS) on therapeutic antibody aggregation is a potential safety and quality gap.

Specific features of a scaffolding antibody light chain.

The antigen-binding sites in conventional antibodies are formed by hypervariable complementarity-determining regions (CDRs) from both heavy chains (HCs) and light chains (LCs). A deviation from this paradigm is found in a subset of bovine antibodies that bind antigens via an ultra-long CDR. The HCs bearing ultra-long CDRs pair with a restricted set of highly conserved LCs that convey stability to the antibody.

Chemometrics in Protein Formulation: Stability Governed by Repulsion and Protein Unfolding.

Therapeutic proteins can be challenging to develop due to their complexity and the requirement of an acceptable formulation to ensure patient safety and efficacy. To date, there is no universal formulation development strategy that can identify optimal formulation conditions for all types of proteins in a fast and reliable manner. In this work, high-throughput characterization, employing a toolbox of five techniques, was performed on 14 structurally different proteins formulated in 6 different buffer conditions and in the presence of 4 different excipients.

Principles of antibodies with ultralong complementarity-determining regions and picobodies.

In contrast to other species, cattle possess exceptional antibodies with ultra-long complementarity-determining regions (ulCDRs) that can consist of 40-70 amino acids. The bovine ulCDR is folded into a stalk and a disulfide-rich knob domain. The binding to the antigen is via the 3-6 kDa knob.

Approaches to expand the conventional toolbox for discovery and selection of antibodies with drug-like physicochemical properties.

Antibody drugs should exhibit not only high-binding affinity for their target antigens but also favorable physicochemical drug-like properties. Such drug-like biophysical properties are essential for the successful development of antibody drug products. The traditional approaches used in antibody drug development require significant experimentation to produce, optimize, and characterize many candidates.

Get what you want: Identifying antibodies against pre-defined epitopes on Frizzled receptors.

In this issue of Structure, Ge et al. report an epitope-directed strategy to select antibodies specific for Frizzled subtypes. Structural and biochemical analyses provide mechanistic insights into the target binding of the isolated antibodies that could guide the design of reagents and therapeutics targeting distinct Frizzled receptors.

Multimeric ACE2-IgM fusions as broadly active antivirals that potently neutralize SARS-CoV-2 variants.

Coronavirus infections are a world-wide threat to human health. A promising strategy to develop a broadly active antiviral is the use of fusion proteins consisting of an antibody IgG Fc region and a human ACE2 domain to which the viral spike proteins bind. Here we create antiviral fusion proteins based on IgM scaffolds.

Insights into the Stabilization of Interferon Alpha by Two Surfactants Revealed by STD-NMR Spectroscopy.

Surfactants are commonly used in biopharmaceutical formulations to stabilize proteins against aggregation. However, the choice of a suitable surfactant for a particular protein is decided mostly empirically, and their mechanism of action on molecular level is largely unknown. Here we show that a straightforward label-free method, saturation transfer difference (STD) nuclear magnetic resonance (NMR) spectroscopy, can be used to detect protein-surfactant interactions in formulations of a model protein, interferon alpha.

It is Never Too Late for a Cocktail - Development and Analytical Characterization of Fixed-dose Antibody Combinations.

Monoclonal antibodies (mAbs) have been immensely successful as biological drugs. However, the treatment of some diseases requires combinations of antibodies that bind to different pharmacological targets. An elegant approach to delivering the therapeutic potential of antibody combinations is to develop drug products based on fixed-dose combinations (FDCs) of co-formulated mAbs.

Antibodies gone bad - the molecular mechanism of light chain amyloidosis.

Light chain amyloidosis (AL) is a systemic disease in which abnormally proliferating plasma cells secrete large amounts of mutated antibody light chains (LCs) that eventually form fibrils. The fibrils are deposited in various organs, most often in the heart and kidney, and impair their function. The prognosis for patients diagnosed with AL is generally poor.

Mechanistic principles of an ultra-long bovine CDR reveal strategies for antibody design.

Antibodies bind antigens via flexible loops called complementarity-determining regions (CDRs). These are usually 6-20 residues long. However, some bovine antibodies have ultra-long CDRs comprising more than 50 residues organized in a stalk and a disulfide-rich knob.

Picomolar inhibition of SARS-CoV-2 variants of concern by an engineered ACE2-IgG4-Fc fusion protein.

SARS-CoV-2 enters host cells after binding through its spike glycoprotein to the angiotensin-converting enzyme 2 (ACE2) receptor. Soluble ACE2 ectodomains bind and neutralize the virus, yet their short in vivo half-live limits their therapeutic use. This limitation can be overcome by fusing the fragment crystallizable (Fc) part of human immunoglobulin G (IgG) to the ACE2 ectodomain, but this bears the risk of Fc-receptor activation and antibody-dependent cellular cytotoxicity.

Combining Unfolding Reversibility Studies and Molecular Dynamics Simulations to Select Aggregation-Resistant Antibodies.

The efficient development of new therapeutic antibodies relies on developability assessment with biophysical and computational methods to find molecules with drug-like properties such as resistance to aggregation. Despite the many novel approaches to select well-behaved proteins, antibody aggregation during storage is still challenging to predict. For this reason, there is a high demand for methods that can identify aggregation-resistant antibodies.

Biophysical Characterization of Binary Therapeutic Monoclonal Antibody Mixtures.

Coformulations containing two therapeutic monoclonal antibodies (mAbs) could offer various benefits like enhanced therapeutic efficacy and better patient compliance. However, there are very few published studies on coformulations and binary mixtures of mAbs. It remains unclear to what extent mAbs with different physicochemical properties can be combined in solution without detrimental effects on protein stability.

Modulated Scanning Fluorimetry Can Quickly Assess Thermal Protein Unfolding Reversibility in Microvolume Samples.

Determining the temperature at which the thermal unfolding of a protein starts becoming irreversible is relevant for many areas of protein research. Until now, published methods cannot determine, within a reasonable time frame and with moderate sample consumption, the exposure temperature that starts causing irreversible protein unfolding. We present modulated scanning fluorimetry (MSF) and share a software (MSF Analyzer), which can be used to derive nonreversibility curves of thermal protein unfolding from a series of incremental temperature cycles performed on only 10 μL samples, consuming as low as a few micrograms of protein.

Binding of excipients is a poor predictor for aggregation kinetics of biopharmaceutical proteins.

One of the major challenges in formulation development of biopharmaceuticals is improving long-term storage stability, which is often achieved by addition of excipients to the final formulation. Finding the optimal excipient for a given protein is usually done using a trial-and-error approach, due to the lack of general understanding of how excipients work for a particular protein. Previously, preferential interactions (binding or exclusion) of excipients with proteins were postulated as a mechanism explaining diversity in the stabilisation effects.

Formulations That Suppress Aggregation During Long-Term Storage of a Bispecific Antibody are Characterized by High Refoldability and Colloidal Stability.

Understanding the formulation features that ensure sufficient stability during long-term storage is critical for developing next-generation therapeutic proteins. In this work, we investigate the physical stability of a bispecific antibody (Bis-mAb) in 12 different formulation conditions. Isothermal chemical denaturation with urea indicates a higher resistance to denaturant-induced unfolding when pH is increased from 5.

Advancing Therapeutic Protein Discovery and Development through Comprehensive Computational and Biophysical Characterization.

Therapeutic protein candidates should exhibit favorable properties that render them suitable to become drugs. Nevertheless, there are no well-established guidelines for the efficient selection of proteinaceous molecules with desired features during early stage development. Such guidelines can emerge only from a large body of published research that employs orthogonal techniques to characterize therapeutic proteins in different formulations.

Orthogonal Techniques to Study the Effect of pH, Sucrose, and Arginine Salts on Monoclonal Antibody Physical Stability and Aggregation During Long-Term Storage.

Understanding the effects of additives on therapeutic protein stability is of paramount importance for obtaining stable formulations. In this work, we apply several high- and medium-throughput methods to study the physical stability of a model monoclonal antibody at pH 5.0 and 6.

Overcoming challenges in co-formulation of proteins with contradicting stability profiles - EPO plus G-CSF.

The co-formulation of drugs is widely used for small molecules, e.g. fixed-dose-combinations of synergistic medicines in the treatment of infections, diabetes or neurodegenerative diseases.

Structure-based discovery of a new protein-aggregation breaking excipient.

Reducing the aggregation of proteins is of utmost interest to the pharmaceutical industry. Aggregated proteins are often less active and can cause severe immune reactions in the patient upon administration. At the same time the biopharmaceutical market is pushing for high concentration formulations and products that do not require refrigerated storage conditions.

Novel non-linear curve fitting to resolve protein unfolding transitions in intrinsic fluorescence differential scanning fluorimetry.

In biotherapeutic protein research, an estimation of the studied protein's thermal stability is one of the important steps that determine developability as a function of solvent conditions. Differential Scanning Fluorimetry (DSF) can be applied to measure thermal stability. Label-free DSF measures amino acid fluorescence as a function of temperature, where conformational changes induce observable peak deformation, yielding apparent melting temperatures.

Application of interpretable artificial neural networks to early monoclonal antibodies development.

The development of a new protein drug typically starts with the design, expression and biophysical characterization of many different protein constructs. The initially high number of constructs is radically reduced to a few candidates that exhibit the desired biological and physicochemical properties. This process of protein expression and characterization to find the most promising molecules is both expensive and time-consuming.