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

Lyophilised protein formulations as a patient-centric dosage form: A contribution toward sustainability paradigm

At present, society has embraced the fact apropos population aging and climate changes, that demand, amongst others, innovative pharmaceutical technologies, emphasising the development of patient-specific delivery systems and thus the provision of efficient and sustainable drugs. Protein drugs for subcutaneous administration, by allowing less frequent application, represent one of the most important parts of the pharmaceutical field, but their development is inevitably faced with obstacles in providing protein stability and suitable formulation viscosity. To gain further knowledge and fill the gaps in the already constructed data platform for the development of monoclonal antibody formulations, we designed a study that examines small model proteins, i.e., bovine serum albumin. The main aim of the presented work is to evaluate the effect of protein concentrations on critical quality attributes of both, pre-lyophilised liquid formulations, and lyophilised products. Through the study, the hypothesis that increasing protein concentration leads to higher viscosity and higher reconstitution time without affecting the stability of the protein was confirmed. The most important finding is that sucrose plays a key role in the lyophilisation of investigated protein, nevertheless, it can be predicted that, to ensure the beneficial effect of mannitol, its amount has to prevail over the amount of sucrose.

Modification of the Physicochemical Properties of Active Pharmaceutical Ingredients via Lyophilization

Bioavailability is an important biopharmaceutical characteristic of active pharmaceutical ingredients (APIs) that is often correlated with their solubility in water. One of the methods of increasing solubility is freeze drying (lyophilization). The article provides a systematic review of studies published from 2012 to 2022 aimed at optimizing the properties of active pharmaceutical ingredients by freeze drying. This review was carried out in accordance with the recommendations of Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA). In general, 141 modifications of 36 APIs attributed to 12 pharmacological groups were reported in selected publications. To characterize the products of phase modification after lyophilization, a complex of analytical methods was used, including microscopic, thermal, X-ray, and spectral approaches. Solubility and pharmacokinetic parameters were assessed. There is a tendency to increase solubility due to the amorphization of APIs during lyophilization. Thus, the alcohol lyophilizate of dihydroquercetin is "soluble" in water compared to the initial substance belonging to the category "very poorly soluble". Based on the analysis of the literature, it can be argued that lyophilization is a promising method for optimizing the properties of APIs.

Freeze-drying of few microliters of antibody formulations to implement 384-wells homogeneous instant assays

Enzyme-linked immunosorbent assay protocols have traditionally complex workflows with several intensive wash steps. Analytical tools with both shorter time-to-result and hands-on-time using smaller sample and assays reagents volumes are now investigated. In this context, fluorescence resonance energy transfer (FRET)-based assays are emerging as one of the most promising analytical tools in high-throughput screening (HTS). These immunoassays allow fast quantification of antigens at the nano-gram level in a final assay volume of only a few μL. We used a homogeneous time-resolved FRET (called HTRF) assay to develop a freeze-dried screening and ready-to-use format with only one rehydration step called "instant assay". To assure optimal performance of the developed homogeneous instant assay, we investigated the critical quality attributes by studying the functionality and stability of the critical reagents and fluorophores. The cyclic adenosine 3'-5'-monophosphate (cAMP) was selected as the antigen target. We tested various formulations (with different buffers, sugars, bulking reagents, surfactants and co-solvants) combined with a slow freezing and the use of an aluminium plate holder during the freeze-drying of few microliter of bioreagents. The optimized freeze-drying procedure permits to preserve more than 70% of Ab recognition properties. The developed off-the-shelf homogeneous FRET immunoassay allows direct and fast quantification of cAMP at a nanogram level.

Practical Advice on Scientific Design of Freeze-Drying Process: 2023 Update

OBJECTIVE

The purpose of this paper is to re-visit the design of three steps in the freeze-drying process, namely freezing, primary drying, and secondary drying steps. Specifically, up-to-date recommendations for selecting freeze-drying conditions are provided based on the physical-chemical properties of formulations and engineering considerations.

METHODS AND RESULTS

This paper discusses the fundamental factors to consider when selecting freezing, primary drying, and secondary drying conditions, and offers mathematical models for predicting the duration of each segment and product temperature during primary drying. Three simple heat/mass transfer primary drying (PD) models were tested, and their ability to predict product temperature and sublimation time showed good agreement. The PD models were validated based on the experimental data and utilized to tabulate the primary drying conditions for common pharmaceutical formulations, including amorphous and partially crystalline products. Examples of calculated drying cycles, including all steps, for typical amorphous and crystalline formulations are provided.

CONCLUSIONS

The authors revisited advice from a seminal paper by Tang and Pikal (Pharm Res. 21(2):191-200, 2004) on selecting freeze-drying process conditions and found that the majority of recommendations are still applicable today. There have been a number of advancements, including methods to promote ice nucleation and computer modeling for all steps of freeze-drying process. The authors created a database for primary drying and provided examples of complete freeze-drying cycles design. The paper may supplement the knowledge of scientists and formulators and serve as a user-friendly tool for quickly estimating the design space.

Freeze-dried nanocrystal dispersion of novel deuterated pyrazoloquinolinone ligand (DK-I-56-1): Process parameters and lyoprotectant selection through the stability study

Recently, nanocrystal dispersions have been considered as a promising formulation strategy to improve the bioavailability of the deuterated pyrazoloquinolinone ligand DK-I-56-1 (7‑methoxy-2-(4‑methoxy-d3-phenyl)-2,5-dihydro-3H-pyrazolo[4,3-c]quinolin-3-one). In the current study, the freeze-drying process (formulation and process parameters) was investigated to improve the storage stability of the previously developed formulation. Different combinations of lyoprotectant (sucrose or trehalose) and bulking agent (mannitol) were varied while formulations were freeze-dried under two conditions (primary drying at -10 or -45 °C). The obtained lyophilizates were characterized in terms of particle size, solid state properties and morphology, while the interactions within the samples were analyzed by Fourier transform infrared spectroscopy. In the preliminary study, three formulations were selected based on the high redispersibility index values (around 95%). The temperature of primary drying had no significant effect on particle size, but stability during storage was impaired for samples dried at -10 °C. Samples dried at lower temperature were more homogeneous and remained stable for three months. It was found that the optimal ratio of sucrose or trehalose to mannitol was 3:2 at a total concentration of 10% to achieve the best stability (particle size < 1.0 μm, polydispersity index < 0.250). The amorphous state of lyoprotectants probably provided a high degree of interaction with nanocrystals, while the crystalline mannitol provided an elegant cake structure. Sucrose was superior to trehalose in maintaining particle size during freeze-drying, while trehalose was more effective in keeping particle size within limits during storage. In conclusion, results demonstrated that the appropriate combination of sucrose/trehalose and mannitol together with the appropriate selection of lyophilization process parameters could yield nanocrystals with satisfactory stability.

Stability of Monoclonal Antibodies as Solid Formulation for Auto-Injectors: A Pilot Study

Drug adherence is a significant medical issue, often responsible for sub-optimal outcomes during the treatment of chronic diseases such as rheumatoid or psoriatic arthritis. Monoclonal antibodies (which are exclusively given parenterally) have been proven to be an effective treatment in these cases. The use of auto-injectors is an effective strategy to improve drug adherence in parenteral treatments since these pen-like devices offer less discomfort and increased user-friendliness over conventional syringe-based delivery. This study aims to investigate the feasibility of including a monoclonal antibody as a solid formulation inside an auto-injector pen. Specifically, the objective was to evaluate the drug stability after a concentration (to reduce the amount of solvent and space needed) and freeze-drying procedure. A preliminary screening of excipients to improve stability was also performed. The nano-DSC results showed that mannitol improved the stability of the concentrated, freeze-dried antibody in comparison to its counterpart without it. However, a small instability of the CH2 domain was still found for mannitol samples, which will warrant further investigation. The present results serve as a stepping stone towards advancing future drug delivery systems that will ultimately improve the patient experience and associated drug adherence.

Application of Quality by Design Principles to the Development of Oral Lyophilizates Containing Olanzapine

Oral lyophilizates are intended for application to the oral cavity or for dispersing in water. The purposes of this research were: (i) to set up the quality by design approach in the development of oral lyophilizates for drug incorporation; and (ii) to evaluate the established approach by comparing its outcomes with experimentally obtained results. Within the knowledge space, properties about drugs, excipients, and the lyophilization process were acquired, followed by the determination of critical quality attributes via risk identification. Risks were assessed by failure mode and effective analysis, which recognized critical material attributes, i.e., type, concentration, particle size, solubility of drug and excipients, while as main critical process parameters, cooling rate, shelf temperature, and chamber pressure during drying were pointed out. Additionally, design space was established using the Minitab^® 17 software and valued with an 88.69% coefficient of determination. A detailed comparison between the model and experimental results revealed that the proposed optimal compositions match in the total concentration of excipients (6%, w/w) in the pre-lyophilized liquid formulation, among which mannitol predominates. On the other hand, a discrepancy regarding the presence of gelatin was detected. The conclusion was that the set model represents a suitable onset toward optimization of drug-based oral lyophilizates development, preventing unnecessary investment of time and resources.

Enabling Efficient Design of Biological Formulations Through Advanced Characterization

The present review summarizes the use of differential scanning calorimetry (DSC) and scattering techniques in the context of protein formulation design and characterization. The scattering techniques include wide angle X-ray diffractometry (XRD), small-angle neutron scattering (SANS) and small-angle X-ray scattering (SAXS). While DSC is valuable for understanding thermal behavior of the excipients, XRD provides critical information about physical state of solutes during freezing, annealing and in the final lyophile. However, as these techniques lack the sensitivity to detect biomolecule-related transitions, complementary characterization techniques such as small-angle scattering can provide valuable insights.

Mannitol as an Excipient for Lyophilized Injectable Formulations

The review summarizes the current state of knowledge of mannitol as an excipient in lyophilized injectable small and large molecule formulations. When compared with glycine, the physicochemical properties of mannitol make it a desirable and preferred bulking agent. Though mannitol is a popular bulking agent in freeze-dried formulations, its use may pose certain challenges such as vial breakage or its existence as a metastable crystalline hemihydrate in the final cake, necessitating appropriate mitigation strategies. The understanding of the phase behavior of mannitol in aqueous systems, during the various stages of freeze-drying, can be critical for the optimization of freeze-drying cycle parameters in multi-component formulations. Finally, using a decision tree as a guiding tool, we demonstrate the use of orthogonal techniques for attaining a stable and cost-effective lyophilized drug product containing mannitol.

Mannitol Hemihydrate in Lyophilized Protein Formulations:Impact of its Dehydration During Storage on Sucrose Crystallinity and Protein Stability

The high propensity of mannitol to crystallize in frozen solutions along with its high eutectic temperature enabling higher primary drying temperatures makes it a good bulking agent. In protein formulations, addition of a sugar (sucrose) that has the ability to remain amorphous throughout processing as well as storage, it is imperative to retain the protein in its native state. It is well known that in the presence of amorphous excipients and protein, mannitol can crystallize as a mixture of anhydrous polymorphs - α-, β- and δ-forms and a hemihydrate form [mannitol hemihydrate (MHH); C₆H₁₄O₆·0.5H₂O]. The conditions of formation of MHH due to processing and formulation variables are well established in the literature. However, MHH's dehydration kinetics on storage and its impact on the stability of a protein has not been systematically evaluated. The overall objective was to identify conditions (temperature and humidity) at which MHH can dehydrate on storage and the consequences of the release of associated water on sucrose phase behavior and protein stability. In a mannitol-sucrose-protein lyophile, the purpose of this study was (i) to investigate the dehydration behavior of MHH (ii) to determine the influence of dehydration on sucrose crystallization and (iii) the effect of moisture released due to MHH dehydration on model protein (Bovine serum albumin, BSA or Human serum albumin, HSA) aggregation. MHH dehydration and sucrose crystallization was observed in cases where the relative humidity was ≥ 55% (open vials). A relative humidity of ≤ 33% RH prevented MHH dehydration while retaining sucrose amorphous. No protein aggregation was observed irrespective of presence of MHH or its dehydration.

Use of a temperature ramp approach (TRA) to design an optimum and robust freeze-drying process for pharmaceutical formulations

Freeze-drying, until now, has been a process that was designed using a trial and error experimental approach. This approach is often material and time consuming, and the resulting freeze-drying processes are neither optimum nor robust. Accordingly, the objective of this study was to develop a simple-to-use and experimental-based approach to design an optimum and robust freeze-drying process for any given formulation. The temperature ramp approach (TRA) detailed in this study involves the implementation of a customized design of experiments (DoE) to perform few (three or four) experiments using a given drug formulation. The DoE results are analyzed to define optimum processing conditions (i.e., shelf temperature and chamber pressure) based on a predefined range of target product temperature for primary drying, which could be defined from formulation characterization at its frozen state. In this study, a successful freeze-drying process of two model formulations using the TRA was designed. Verification experiments at the optimum processing conditions showed excellent agreement in both product temperature and sublimation rate with the values obtained using the TRA. Thus, the TRA detailed in this study offers a significant advantage to reduce development time and material, and enhance the efficiency and robustness of the resulting freeze-drying process.