Microwave-Assisted Freeze-Drying: Impact of Microwave Radiation on the Quality of High-Concentration Antibody Formulations.

Microwave-assisted freeze-drying (MFD) offers significant time savings compared to conventional freeze-drying (CFD). While a few studies have investigated the stability of biopharmaceuticals with low protein concentrations after MFD and storage, the impact of MFD on high-concentration monoclonal antibody (mAb) formulations remains unclear. In this study, we systematically examined the effect of protein concentration in MFD and assessed protein stability following MFD, CFD, and subsequent storage using seven protein formulations with various stabilizers and concentrations. We demonstrated that microwaves directly interact with the active pharmaceutical ingredient (API), leading to decreased physical stability, specifically aggregation, in high-concentration antibody formulations. Furthermore, typically used sugar:protein ratios from CFD were insufficient for stabilizing mAbs when applying microwaves. We identified the intermediate drying phase as the most critical for particle formation, and cooling the samples provided some protection for the mAb. Our findings suggest that MFD technology may not be universally applicable to formulations well tested in CFD and could be particularly beneficial for formulations with low API concentrations requiring substantial amounts of glass-forming excipients, such as vaccines and RNA-based products.

Accelerated Production of Biopharmaceuticals via Microwave-Assisted Freeze-Drying (MFD).

Recently, attention has been drawn to microwave-assisted freeze-drying (MFD), as it drastically reduces the typically long drying times of biopharmaceuticals in conventional freeze-drying (CFD). Nevertheless, previously described prototype machines lack important attributes such as in-chamber freezing and stoppering, not allowing for the performance of representative vial freeze-drying processes. In this study, we present a new technical MFD setup, designed with GMP processes in mind. It is based on a standard lyophilizer equipped with flat semiconductor microwave modules. The idea was to enable the retrofitting of standard freeze-dryers with a microwave option, which would reduce the hurdles of implementation. We aimed to collect process data with respect to the speed, settings, and controllability of the MFD processes. Moreover, we studied the performance of six monoclonal antibody (mAb) formulations in terms of quality after drying and stability after storage for 6 months. We found drying processes to be drastically shortened and well controllable and observed no signs of plasma discharge. The characterization of the lyophilizates revealed an elegant cake appearance and remarkably good stability in the mAb after MFD. Furthermore, overall storage stability was good, even when residual moisture was increased due to high concentrations of glass-forming excipients. A direct comparison of stability data following MFD and CFD demonstrated similar stability profiles. We conclude that the new machine design is highly advantageous, enabling the fast-drying of excipient-dominated, low-concentrated mAb formulations in compliance with modern manufacturing technology.

A Novel MATLAB®-Algorithm-Based Video Analysis to Quantitatively Determine Solution Creeping in Intact Pharmaceutical Glass Vials.

During the filling process of a biopharmaceutical drug product (DP), a liquid DP film might creep up the inner vial wall which is barely discernible, appears as milky-white haze after lyophilisation and is known as fogging. Creeping and fogging are mainly dependent on the primary packaging material surface and its hydration, vial preparation process as well as DP composition. The occurrence of both can impede visual inspection and might lead to DP rejection. Hence, our studies focused on the early detection of liquid solution and glass vial surface interaction directly after filling. For a fast and highly sensitive evaluation a novel video-based analysis was used. To our knowledge, this is the first time a MATLAB®-algorithm-based video analysis was applied to quantitatively determine creeping time-resolved. Furthermore, creeping in dependence of vial processing sites, surfactant type and concentration, filling temperature, and vial format were investigated. The results were verified using orthogonal conventional methods such as surface tension, wetting behaviour, and contact angle measurements, as well as ToF-SIMS, ICP-MS, and SEM. Additionally, the methods applied were assessed regarding their cross-validation capability. The observations indicate that the vial preparation process can have a pronounced impact on alteration of the glass vial surface and related creeping behaviour of the filled solution.

100% Control of Controlled Ice Nucleation Vials by Camera-Supported Optical Inspection in Freeze-Drying.

Freeze-drying is the drying technology of choice for sensitive biological drugs. On the one side, it is admired for its suitability for the stabilization of sensitive molecules. On the other side, it is a time-consuming production step posing challenges in process development and technology transfer. The application of controlled ice nucleation is one elegant approach to shorten freeze-drying times significantly and at the same time increase batch homogeneity. However, a reliable 100% control of the controlled nucleation step in each vial is essential, considering the impact of the nucleation temperature on product quality attributes. In this study, we introduce a camera-supported optical inspection method that utilizes the different superficial cake structures seen in controlled and random nucleated lyophilizates. Derived from the grayscale analysis, the new distinguishing criterion "average edge brightness" is introduced. Four different formulations containing Sucrose, Trehalose, and/or bovine serum albumin were freeze dried with random or controlled nucleation and analyzed with the new technology. A proof of concept is provided by the analysis of a similar-to-market lyophilized monoclonal antibody formulation freeze-dried with three different freezing protocols covering different nucleation profiles. For all investigated formulations and process conditions, the clear discrimination of controlled and randomly nucleated vials was possible. By this, the technology allowed for reliable, noninvasive, and automatable 100% monitoring of controlled nucleation success after freeze-drying.

Microwave-Assisted Freeze-Drying of Monoclonal Antibodies: Product Quality Aspects and Storage Stability.

In order to overcome the downside of long conventional freeze-drying (CFD) process times for monoclonal antibody formulations, microwave-assisted freeze-drying (MFD) was introduced. Recently, the general applicability and potential shortening of drying times were shown. However, little is known about the storage stability of MFD products compared to CFD references. Additionally, batch homogeneity issues were seen within MFD in the past. In this study, we examined four different formulations of two different monoclonal antibodies using three different glass-forming excipients: sucrose, trehalose, and arginine phosphate. These formulations were freeze-dried with two different drying protocols (CFD and MFD), stored for 24 weeks, and analyzed for solid-state and protein-related quality attributes. Moreover, a new microwave generator setup was investigated for its potential to improve batch homogeneity. In all investigated formulations, comparable stability profiles were found, although the classical magnetron generator led to inferior batch homogeneity with respect to residual moisture distribution. In contrast, the new MFD setup indicated the potential to approximate batch homogeneity to the level of CFD. However, for future applications, there is an unabated need for new machine designs to comply with pharmaceutical manufacturing requirements.

Polysorbate degradation in biotherapeutic formulations: Identification and discussion of current root causes.

Biotherapeutic protein formulations are often high concentration liquid protein solutions, which are required to be stable under pharmaceutically relevant storage conditions and presence of external stress. Non-ionic detergents like polysorbate have been the most commonly used detergent to maintain formulation stability. Recently, particle formation in polysorbate containing biotherapeutic formulations has arisen as a major quality concern and potential patient risk factor. In this review, we provide a general overview into (i) degradation of polysorbates, (ii) polysorbate analytics, (iii) particle formation induced by polysorbate degradation and root causes thereof, (iv) particle composition and (v) various influencing factors that might lead to particle formation. Consequently, we explore the role of polysorbate degradation in particle formation. Additionally, various degradation pathways and the current discussed root causes are reviewed.

A Comparison of Controlled Ice Nucleation Techniques for Freeze-Drying of a Therapeutic Antibody.

The aim of this study was to investigate if mechanistically different controlled ice nucleation techniques in freeze-drying are comparable to each other with respect to drying process performance and product quality attributes. Therefore, we studied 3 different model formulations including amorphous (sucrose, trehalose) and semi-crystalline (mannitol:sucrose 4:1) solids containing a monoclonal antibody IgG1 (5 g/L) processed either by application of ice fog or depressurization technique setting an ice nucleation temperature of -5°C. Subsequently, the same freeze-drying protocol on identical machinery was applied. The results showed that the techniques are comparable with respect to the thermal history of product temperature sensors and primary drying time, solid state- and protein-related product quality attributes. All analytics comprising Karl Fischer titration, X-ray powder diffraction and Brunauer-Emmet-Teller as well as high-performance size exclusion chromatography, turbidity and subvisible particle counting using flow-imaging microscopy exhibited similarity and comparability among the controlled nucleation protocols.

Significant Drying Time Reduction Using Microwave-Assisted Freeze-Drying for a Monoclonal Antibody.

Microwave-assisted freeze-drying (MFD) is a rapid drying process well known in food technology. However, little is known about its application to biologicals. In this study, we investigated the applicability and feasibility of this technology to different monoclonal antibody formulations and the influence on the resulting product properties. Moreover, one of our main objectives was to study if significant reductions in drying times could be achieved. In addition, the effect of the drying process on the accelerated stability of a sucrose-based antibody formulation at 40°C and 25°C over 12 weeks was investigated. MFD resulted in drying time reduction >75%. For all model formulations, cake appearance and solid state properties were found to be comparable to standard lyophilized products. These formulations covered a wider range of lyophilization excipients comprising sucrose and trehalose, semi-crystalline forming solids like mannitol:sucrose mixtures and others like arginine phosphate and a mixture of 2-hydroxypropyl-ß-cyclodextrin with sucrose. Moreover, comparable low changes in relative monomer content, the relative amount of soluble aggregates and cumulative particles ≥1 µm per mL were observed over 12 weeks of storage, regardless of the drying technology. This makes MFD a promising innovative alternative for the rapid production of freeze-dried biologicals while maintaining product quality.