Effect of Collapse on the Stability of Freeze-Dried Recombinant Factor VIII and α-amylase

Development of monoclonal antibodies in tablet form: A new approach for local delivery

Among the various pharmaceutical forms, tablets offer numerous advantages, like ease of administration, cost-effectiveness in production, and better stability of biomolecules. Beyond these benefits, the tablet form opens up possibilities for alternative routes for the local delivery of biopharmaceuticals such as oral or vaginal administration, thereby expanding the therapeutic applications of these biomolecules and overcoming the inconvenients associated with parenteral administration. However, to date there is limited information on the feasibility of developing biomolecules in the tablet form. In this study, we have evaluated the feasibility of developing monoclonal antibodies in the tablet form while preserving their biological properties. Different excipients and process parameters were studied to assess their impact on the antibody's integrity during tableting. ELISA results show that applying compression pressure up to 100 MPa is not detrimental to the antibody's binding properties when formulated from a lyophilized powder containing trehalose or sucrose as the major excipient. This observation was confirmed with SPR and ultracentrifugation experiments, which demonstrated that neither the binding affinity for both Fc and Fab antibody fragments nor its aggregation rate are affected by the tableting process. After compression, the tablets containing the antibodies have been shown to be stable for 6 months at room temperature.

Part I: Significant reduction of lyophilization process times by using novel matrix based scaffolds

To improve the long-term stability of drugs with limited stability (e.g., biologicals such as monoclonal antibodies, antibody drug conjugates or peptides), some pharmaceuticals endure a lengthy and cost-intensive process called lyophilization. While the shelf life of lyophilized drugs may be prolonged compared to their liquid form, the drawbacks come in the form of intensified manufacturing, preparation, and dosing efforts. The use of glass vials as the primary container unit for lyophilized products hinders their complication-free, fast and flexible use, as they require a skilled healthcare professional and an aseptic environment in which to prepare them. The feasibility of substituting glass vials with novel container designs offering the complete transfer of the lyophilizate cake into modern administration devices, while reducing the economic footprint of the lyophilization process, was investigated. The lyophilization process of a monoclonal antibody solution was studied by assessing primary drying conditions, homogeneity of the drying process, and critical quality attributes after successful lyophilization. The creation of novel container designs utilized vacuum-forming to generate confined containers with removable bottoms and rapid prototyping, including subtractive and additive manufacturing methods, to generate porous 3D structures for drug housing. The novel container designs generated lyophilizates twice as fast and achieved a threefold faster reconstitution compared to their vial counterparts, without adaptation of the processing conditions. We conclude that the use of intermediate process containers offers significant relief for healthcare professionals in terms of reduced probability of handling errors, while drug manufacturers benefit from the accelerated processing times, increased batch homogeneity, and sustainability.

Assessment of quality and pre-clinical efficacy of a newly developed polyvalent antivenom against the medically important snakes of Sri Lanka

Snake envenomation is a severe problem in Sri Lanka (SL) and Indian polyvalent antivenom (PAV) is mostly used for treating snakebite albeit due to geographical variation in venom composition, Indian PAV shows poor efficacy in neutralizing the lethality and toxicity of venom from the same species of snakes in SL. Therefore, the quality and in vivo venom neutralization potency of a country-specific PAV produced against the venom of the five most medically important snakes of SL (Daboia russelii, Echis carinatus, Hypnale hypnale, Naja naja, Bungarus caeruleus) was assessed. LC-MS/MS analysis of two batches of PAV showed the presence of 88.7-97.2% IgG and traces of other plasma proteins. The tested PAVs contained minor amounts of undigested IgG and F(ab')2 aggregates, showed complement activation, were devoid of IgE, endotoxin, and content of preservative was below the threshold level. Immunological cross-reactivity and in vitro neutralization of enzymatic activities, pharmacological properties demonstrated superior efficacy of SL PAV compared to Indian PAV against SL snake venoms. The in vivo neutralization study showed that the tested PAVs are potent to neutralize the lethality and venom-induced toxicity of SL snake venoms. Therefore, our study suggests that introduction of SL-specific PAV will improve snakebite management in SL.

Cycle Development in a Mini-Freeze Dryer: Evaluation of Manometric Temperature Measurement in Small-Scale Equipment

The objective of this research was to assess the applicability of manometric temperature measurement (MTM) and SMART™ for cycle development and monitoring of critical product and process parameters in a mini-freeze dryer using a small set of seven vials. Freeze drying cycles were developed using SMART™ which automatically defines and adapts process parameters based on input data and MTM feedback information. The freeze drying behavior and product characteristics of an amorphous model system were studied at varying wall temperature control settings of the cylindrical wall surrounding the shelf in the mini-freeze dryer. Calculated product temperature profiles were similar for all different wall temperature settings during the MTM-SMART™ runs and in good agreement with the temperatures measured by thermocouples. Product resistance profiles showed uniformity in all of the runs conducted in the mini-freeze dryer, but absolute values were slightly lower compared to values determined by MTM in a LyoStar™ pilot-scale freeze dryer. The resulting cakes exhibited comparable residual moisture content and optical appearance to the products obtained in the larger freeze dryer. An increase in intra-vial heterogeneity was found for the pore morphology in the cycle with deactivated wall temperature control in the mini-freeze dryer. SMART™ cycle design and product attributes were reproducible and a minimum load of seven 10R vials was identified for more accurate MTM values. MTM-SMART™ runs suggested, that in case of the wall temperature following the product temperature of the center vial, product temperatures differ only slightly from those in the LyoStar™ freeze dryer.

Instability of therapeutic proteins - An overview of stresses, stabilization mechanisms and analytical techniques involved in lyophilized proteins

Solid-state is the preferred choice for storage of protein therapeutics to improve stability and preserve the biological activity by decreasing the physical and chemical degradation associated with liquid protein formulations. Lyophilization or freeze-drying is an effective drying method to overcome the instability problems of proteins. However, the processing steps (freezing, primary drying and secondary drying) involved in the lyophilization process can expose the proteins to various stress and harsh conditions, leading to denaturation, aggregation often a loss in activity of protein therapeutics. Stabilizers such as sugars and surfactants are often added to protect the proteins against physical stress associated with lyophilization process and storage conditions. Another way to curtail the degradation of proteins due to process related stress is by modification of the lyophilization process. Slow freezing, high nucleation temperature, decreasing the extent of supercooling, and annealing can minimize the formation of the interface (ice-water) by producing large ice crystals with less surface area, thereby preserving the native structure and stability of the proteins. Hence, a thorough understanding of formulation composition, lyophilization process parameters and the choice of analytical methods to characterize and monitor the protein instability is crucial for development of stable therapeutic protein products. This review provides an overview of various stress conditions that proteins might encounter during lyophilization process, mechanisms to improve the stability and analytical techniques to tackle the proteins instability during both freeze-drying and storage.

Be Aggressive! Amorphous Excipients Enabling Single-Step Freeze-Drying of Monoclonal Antibody Formulations

Short freeze-drying cycles for biopharmaceuticals are desirable. Formulations containing an amorphous disaccharide, such as sucrose, are prone to collapse upon aggressive primary drying at higher shelf temperature. We used 2-hydroxypropyl-betacyclodextrin (HPBCD) in combination with sucrose and polyvinylpyrrolidone (PVP) to develop an aggressive lyophilization cycle for low concentration monoclonal antibody (mAb) formulations. Glass transition temperature and collapse temperature of the formulations were determined, and increasingly aggressive cycle parameters were applied. Using a shelf temperature of +30 °C during primary drying, the concept of combining sublimation and desorption of water in a single drying step was investigated. Cake appearance was evaluated visually and by micro-computed tomography. Lyophilisates were further analyzed for reconstitution time, specific surface area, residual moisture, and glass transition temperature. We demonstrated the applicability of single-step freeze-drying, shortening the total cycle time by 50% and providing elegant lyophilisates for pure HPBCD and HPBCD/sucrose formulations. HPBCD/PVP/sucrose showed minor dents, while good mAb stability at 10 mg/mL was obtained for HPBCD/sucrose and HPBCD/PVP/sucrose when stored at 40 °C for 3 months. We conclude that HPBCD-based formulations in combination with sucrose are highly attractive, enabling aggressive, single-step freeze-drying of low concentration mAb formulations, while maintaining elegant lyophilisates and ensuring protein stability at the same time.

Development of Freeze-Drying Cycles for Pharmaceutical Products Using a Micro Freeze-Dryer

This article aims to investigate how a small-scale freeze-dryer can be used for process design. The system encompasses a temperature controlled metallic ring that surrounds a small batch of vials, in contact with the external vials through removable thermal conductors. The temperature of the ring can be modified to keep a constant difference with the temperature of one or more vials of the batch. In this article, an extensive validation of the system is given, considering 10% w/w sucrose and 5% w/w mannitol solutions, processed in different types of vials (6 R and 20 R) and in different operating conditions. The micro freeze-dryer was also shown to be able to provide accurate estimates of the overall heat transfer coefficient from the shelf to the product in the vials (K_v) and of the resistance of the dried cake to vapor flux (R_p): both values appeared to be very close to those obtained for the same case studies in a pilot-scale unit. Finally, the use of the micro freeze-dryer to control product temperature and drying time values to simulate a pilot-scale unit was addressed, thus demonstrating the adequacy of this system for process scaleup.

An Experimental-Based Approach to Construct the Process Design Space of a Freeze-Drying Process: An Effective Tool to Design an Optimum and Robust Freeze-Drying Process for Pharmaceuticals

The application of quality by design (QbD) is becoming an integral part of the formulation and process development for pharmaceutical products. An essential feature of the QbD philosophy is the design space. In this sense, a new approach to construct a process design space (PDS) for the primary drying section of a freeze-drying process is addressed in this paper. An effective customized design of experiments (DoE) is developed for freeze-drying experiments. The results obtained from the DoE are then used to construct the product-based PDS. The proposed product-based PDS construction approach has several advantages, including (1) eliminating assumptions on the heat transfer coefficient and dried product resistance, as it is constructed from experimental results specifically obtained from a given formulation, yielding more realistic and reliable results and (2) PDS construction based on a narrow range of product temperatures and considering the variations in product temperature and sublimation rate of vials across a shelf. This guarantees the effectiveness and robustness of the process and facilitates the process scale-up and transfer. The PDS developed herein was experimentally verified. The PDS predicted parameters were in excellent agreement with the experimentally obtained parameters.

An Innovative Ultrasonic Apparatus and Technology for Diagnosis of Freeze-Drying Process

The freeze-drying process removes water from a product through freezing, sublimation and desorption procedures. However, the extreme conditions of the freeze-drying environment, such as the limited space, vacuum and freezing temperatures of as much as -50 °C, may block the ability to use certain diagnostic sensors. In this paper, an ultrasonic transducer (UT) is integrated onto the bottom of a specially designed frozen bottle for the purpose of observing the freeze-drying process of water at varying amounts. The temperatures and visual observations made with a camera are then compared with the corresponding ultrasonic signatures. Among all of the diagnostic tools and technologies available, only ultrasonic and visual records are able to analyze the entire progression of the freeze-drying process of water. Compared with typical experiment settings, the indication of drying point for water by the amplitude variations of ultrasonic L³ echo could reduce the process period and energy consumption. This study demonstrates how an innovative frozen bottle, an integrated ultrasonic sensor and diagnostic methods used to measure and optimize the freeze-drying process of water can save energy.

The formation and effect of mannitol hemihydrate on the stability of monoclonal antibody in the lyophilized state

Crystalline bulking agent in lyophilized biopharmaceutical formulations provides an elegant lyophilized cake structure and allows aggressive primary drying conditions. The interplay between amorphous and crystalline state of excipients heavily influence the stability of lyophilized biological products and should be carefully evaluated in the formulation and process development phase. This study focuses on: (1) elucidating the influence of formulation and lyophilization process variables on the formation of different states of mannitol and (2) its impact on model monoclonal antibody stability when compared to sucrose. The main aim of the present research work was to study the influence of different mannitol to sucrose ratios and monoclonal antibody concentrations on mannitol physical form established during lyophilization. In addition, also the effect of process variables on mannitol hemihydrate (MHH) formation was under investigation. Thermal analysis and powder X-ray diffraction results revealed that the ratio between sucrose and mannitol and mAb concentration have a decisive impact on mannitol crystallization. Namely, increasing amount of mannitol and monoclonal antibody resulted in decreasing formation of MHH. From the process parameters investigated, a higher secondary drying temperature has the biggest impact on the complete dehydration of MHH. Specifically, higher secondary drying temperature reflected in complete dehydration of MHH. Annealing temperature was shown to affect the MHH content in the final product, wherein the higher annealing temperature was preferential for formation of anhydrous mannitol. Temperature stress stability study revealed that the most important parameter influencing monoclonal antibody stability is the ratio of protein to sucrose. Contrary to widespread assumption, we did not detect any impact of MHH on the stability of the investigated monoclonal antibody.

Lyophilization of Liposomal Formulations: Still Necessary, Still Challenging

Nowadays, the freeze-drying of liposome dispersions is still necessary to provide a solid dosage form intended for different routes of administration (i.e., parenteral, oral, nasal and/or pulmonary). However, after decades of studies the optimization of process conditions remains still challenging since the freezing and the dehydration destabilize the vesicle organization with the concomitant drug leakage. Starting from the thermal properties of phospholipids, this work reviews the main formulation and process parameters which can guarantee a product with suitable characteristics and increase the efficiency of the manufacturing process. In particular, an overview of the cryo- and/or lyo-protective mechanisms of several excipients and the possible use of co-solvent mixtures is provided. Attention is also focused on the imaging methods recently proposed to characterize the appearance of freeze-dried products and liposome dispersions upon reconstitution. The combination of such data would allow a better knowledge of the factors causing inter-vials variability in the attempt to improve the quality of the final medicinal product.

On the Use of Infrared Thermography for Monitoring a Vial Freeze-Drying Process

Monitoring a vial freeze-drying process without interfering with product dynamics is a challenging issue. This article presents a novel device constituted by an infrared camera designed to be placed inside the drying chamber, able to monitor the temperature of the vials, very close to that of the product inside. By this way it is possible to estimate the ending point of the primary drying, the heat transfer coefficient to the product (K_v), and the resistance of the dried product to vapor flux (R_p). Experiments were carried out in a pilot-scale freeze-dryer, processing 5% and 10% sucrose solutions at different values of shelf temperature and chamber pressure, using both thermocouples and the IR camera to track product dynamics. Results evidence that the measurements (of temperature) and the estimates (of the ending point of the main drying and of K_v and R_p) obtained using the 2 systems are very close, thus validating the IR camera as an effective process analytical technologies for the freeze-drying process. Besides, it was shown that the presence of the IR camera in the chamber is not responsible for any additional heating to the product and that monitored vials are representative of the majority of the vials of the batch.

Impact of fast and conservative freeze-drying on product quality of protein-mannitol-sucrose-glycerol lyophilizates

PURPOSE

Mannitol/sucrose formulations are employed to generate lyophilizates for biopharmaceuticals with an elegant cake appearance. The aim of this study was to dry protein/mannitol/sucrose formulations as fast as possible without loss of cake appearance and protein stability. Glycerol was included as potential additional protein stabilizer. Three proteins (lysozyme and two monoclonal antibodies) at low and high concentration were analyzed comparing fast with conservative freeze-drying.

METHODS

Freeze-drying cycle development was carried out with mannitol/sucrose formulations. A product temperature (Tp) close to the Te of mannitol and clearly above the Tg' of sucrose was targeted. Protein formulations were exposed to the final fast lyophilisation process and to a conservative freeze-drying cycle. Lyophilizates were characterized by differential scanning calorimetry, Karl-Fischer titration and X-ray diffractometry. Additionally, macroscopic cake appearance and reconstitution times were evaluated. Protein stability was characterized by UV/Vis spectroscopy, light obscuration and size exclusion chromatography.

RESULTS

The fast freeze-drying cycle resulted in a primary drying time of 7 h (Tp: -10 °C) and a secondary drying time of 2 h in contrast to 47 h (Tp: -39 °C) and 12 h for the conservative cycle. Lyophilizates showed Tg values above 60 °C, a residual moisture level of 1%, reconstitution times of less than 35 s, δ-mannitol and elegant cake appearance. Mannitol/sucrose ratios below 4/1 did not lead to complete mannitol crystallization and were therefore not suitable for the selected process conditions. Characterisation of protein stability rendered low aggregation and particle levels for both, fast and conservative freeze-drying conditions.

CONCLUSIONS

It was shown that fast freeze-drying of mannitol/sucrose formulations above Tg' at a Tp of -10 °C resulted in good protein process stability and appropriate cake characteristics at maximum time reduction.

Formulation for a novel inhaled peptide therapeutic for idiopathic pulmonary fibrosis

A caveolin-1 scaffolding domain, CSP7, is a newly developed peptide for the treatment of idiopathic pulmonary fibrosis. To develop a CSP7 formulation for further use we have obtained, characterized and compared a number of lyophilized formulations of CSP7 trifluoroacetate with DPBS and in combination with excipients (mannitol and lactose at molar ratios 1:5, 70 and 140). CSP7 trifluoroacetate was stable (>95%) in solution at 5 and 25 °C for up to 48 h and tolerated at least 5 freeze/thaw cycles. Lyophilized cakes of CSP7 trifluoroacetate with excipients were stable (>96%) for up to 4 weeks at room temperature (RT), and retained more than 98% of the CSP7 trifluoroacetate in the solution at 8 h after reconstitution at RT. The lyophilized CSP7 formulations were stable for up to 10 months at 5 °C protected from moisture. Exposure of the lyophilized cakes of CSP7 to 75% relative humidity (RH) resulted in an increase in the absorbed moisture, promoted crystallization of the excipients and induced reversible formation of CSP7 aggregates. Increased molar ratio of mannitol slightly affected formation of the aggregates. In contrast, lactose significantly decreased (up to 20 times) aggregate formation with apparent saturation at the molar ratio of 1:70. The possible mechanisms of stabilization of CSP7 trifluoroacetate in solid state by lactose include physical state of the bulking agent and the interactions between lactose and CSP7 trifluoroacetate (e.g. formation of a Schiff base with the N-terminal amino group of CSP7). Finally, CSP7 trifluoroacetate exhibited excellent stability during nebulization of formulations containing mannitol or lactose.

Model-Based PAT for Quality Management in Pharmaceuticals Freeze-Drying: State of the Art

Model-based process analytical technologies can be used for the in-line control and optimization of a pharmaceuticals freeze-drying process, as well as for the off-line design of the process, i.e., the identification of the optimal operating conditions. This paper aims at presenting the state of the art in this field, focusing, particularly, on three groups of systems, namely, those based on the temperature measurement (i.e., the soft sensor), on the chamber pressure measurement (i.e., the systems based on the test of pressure rise and of pressure decrease), and on the sublimation flux estimate (i.e., the tunable diode laser absorption spectroscopy and the valveless monitoring system). The application of these systems for in-line process optimization (e.g., using a model predictive control algorithm) and to get a true quality by design (e.g., through the off-line calculation of the design space of the process) is presented and discussed.

On the Design of a Fuzzy Logic-Based Control System for Freeze-Drying Processes

This article is focused on the design of a fuzzy logic-based control system to optimize a drug freeze-drying process. The goal of the system is to keep product temperature as close as possible to the threshold value of the formulation being processed, without trespassing it, in such a way that product quality is not jeopardized and the sublimation flux is maximized. The method involves the measurement of product temperature and a set of rules that have been obtained through process simulation with the goal to obtain a unique set of rules for products with very different characteristics. Input variables are the difference between the temperature of the product and the threshold value, the difference between the temperature of the heating fluid and that of the product, and the rate of change of product temperature. The output variables are the variation of the temperature of the heating fluid and the pressure in the drying chamber. The effect of the starting value of the input variables and of the control interval has been investigated, thus resulting in the optimal configuration of the control system. Experimental investigation carried out in a pilot-scale freeze-dryer has been carried out to validate the proposed system.

The influence of excipients commonly used in freeze drying on whole blood coagulation dynamics assessed by rotational thromboelastometry

BACKGROUND

Lyophilized reagents are used on a daily basis in coagulation diagnostics. They often contain a number of excipients in addition to the active compound. Some of these excipients may, however, influence coagulation dynamics.

METHODS

Besides from plasmatic coagulation bulking agents may influence platelet properties. We therefore studied the influence of a variety of bulking agents (glycine, mannitol, sucrose and trehalose) as well as a surfactant (Tween® 80) on whole blood coagulation using thromboelastometry (ROTEM®) and platelet function analysis (ROTEM® platelet).

RESULTS

Both disaccharides as well as Tween® 80 did not influence whole blood coagulation in the concentration range investigated. The addition of glycine and mannitol solutions to the ROTEM® measurement leads to an impaired clot formation as well as overall clot strength while clotting initiation remained barely influenced. Hypertonic glycine and mannitol solutions exhibit different clot formation impairment when correlated to their osmolar concentration and compared to equally osmolar NaCl-solutions. The effect of glycine was assigned to fibrin formation impairment identified with the FIBTEM assay. Platelet function analysis revealed that hypertonic glycine solutions do not alter platelet function but hypertonic mannitol and NaCl solutions do.

CONCLUSIONS

While the influence observed for glycine may be due to fibrinogen precipitation, the mechanism of mannitol appears to be more complex as platelet function as well as fibrin-based clot formation are influenced. This study therefore demonstrates the necessity to check for coagulation impairment due to compounds contained in lyophilized reagents.

Recent advances and further challenges in lyophilization

While entering a new century, lyophilization in the pharmaceutical field has been subjected to ongoing development and steady expansion. This review aims to highlight recent advances but also to discuss further challenges in lyophilization. At first, the expanded range of pharmaceutical applications based on lyophilization is summarized. Moreover, novel formulation aspects and novel container systems are discussed, and the importance of the freezing step is outlined. Furthermore, the dogma of "never lyophilize above the glass transition temperature" is argued, and recent insights into novel stabilization concepts are provided. Process analytical technology (PAT) and quality by design (QbD) are now leading issues, and the design of the lyophilization equipment also might have to be reconsidered in the future.

Accurate prediction of collapse temperature using optical coherence tomography-based freeze-drying microscopy

The objective of this study was to assess the feasibility of developing and applying a laboratory tool that can provide three-dimensional product structural information during freeze-drying and which can accurately characterize the collapse temperature (Tc ) of pharmaceutical formulations designed for freeze-drying. A single-vial freeze dryer coupled with optical coherence tomography freeze-drying microscopy (OCT-FDM) was developed to investigate the structure and Tc of formulations in pharmaceutically relevant products containers (i.e., freeze-drying in vials). OCT-FDM was used to measure the Tc and eutectic melt of three formulations in freeze-drying vials. The Tc as measured by OCT-FDM was found to be predictive of freeze-drying with a batch of vials in a conventional laboratory freeze dryer. The freeze-drying cycles developed using OCT-FDM data, as compared with traditional light transmission freeze-drying microscopy (LT-FDM), resulted in a significant reduction in primary drying time, which could result in a substantial reduction of manufacturing costs while maintaining product quality. OCT-FDM provides quantitative data to justify freeze-drying at temperatures higher than the Tc measured by LT-FDM and provides a reliable upper limit to setting a product temperature in primary drying.