Development of monoclonal antibodies in tablet form: A new approach for local delivery
Abstract
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.
Introduction
Since the introduction of the first therapeutic monoclonal antibody (mAb) in 1985 (Muromonab) (Ecker et al., 2015), mAbs have experienced significant growth in the biopharmaceutical industry. This growth is reflected in a few key statistics: 13 new antibodies (or derivatives) obtained a first approval in either the US or EU each year in 2018, 2021, and 2022 and 12 in 2020 (Kaplon et al., 2023). Furthermore, since the beginning of 2023, over 20 % of new drug approvals granted by the FDA’s Center for Drug Evaluation and Research have been related to antibodies (Research, 2023). Throughout these years, the development of therapeutic mAbs has revolutionized the treatment of a broad range of diseases in various fields such as oncology, dermatology, neurology, autoimmune disorders or infectious diseases (Mullard, 2021). The great interest in therapeutic antibodies can be explained on the one hand by their multiple natural functions, including neutralization, opsonization, antibody-dependent cell-mediated cytotoxic (ADCC) activity, or complement-dependent cytotoxic (CDC) activity, which allow a wide range of pharmacological applications. On the other hand, therapeutic mAbs exhibits good safety profiles.
This is partly due to their high antigenic specificity but also thanks to significant progress in their development methods, particularly through genetic engineering, which has progressively enabled the production of partially or fully humanized antibodies, resulting in reduced immunogenicity effects for clinical use in humans. Nonetheless, despite this attractive and promising market, the formulation of mAbs remains challenging. Antibody’s characteristics such as poor intestinal permeability (high molecular weight) or proteinaceous nature that makes them sensitive to gastric pH and enzymes, quickly ruled out the possibility of administering them through the preferred non-invasive oral route and so, their development has so far been oriented on liquid or freeze-dried (FD) formulations for parenteral administration (intravenous, subcutaneous routes). Parenteral administration however, has several technical, clinical, or patient-related disadvantages.
Firstly, the development of formulations associated with parenteral administrations requires the implementation of aseptic processes and, particularly for solution-based formulations, involves a logistical challenge associated to cold chain maintenance during their transport and storage. Secondly, parenteral administration results in poor patient compliance since administration generally requires a trained healthcare professional which can limit accessibility and increase healthcare costs. But ultimately, one of the major limitations is related to their pharmacokinetics properties. As large and polar molecules, antibodies have a low tissues distribution and are majorly confined within the vascular or lymphatic spaces following systemic administration. As a consequence, delivering antibodies to maintain the drug at therapeutic level is challenging and may require the administration of a large quantity of mAb or even multiply injections so that a sufficient quantity of molecules reaches the target organ/tissue
Considering these limitations, the development of alternative dosage forms for local mAbs delivery may be highly revelant. This is particularly true for therapies based on passive topical immunization, where the absorption of the antibody is not necessary to obtain therapeutic activity. Examples can include the management of chronic conditions such as Crohn’s disease or ulcerative colitis that currently rely on immunomodulation therapy with mAbs (infliximab, velodizumab), and for which local delivery of mAbs directly to the intestinal or rectal mucosas could be judicious to favor the local anti-inflammatory therapeutic effects and improve patient comfort. Other examples can also include common non-invasives bacterial, fungal, or viral infections of the buccal, gastrointestinal or vaginal mucosal surfaces. For these types of infections, a topical administration of antibodies has demonstrated effectiveness in preventing infectious agents from attaching and colonizing the epithelium (Lehner et al., 1985), or penetrating and replicating in the mucosa (Veazey et al., 2003, Yang et al., 2020). Such a therapeutic objective can be easily accessible by the use of conventional pharmaceutical forms for topical application.
Generally topical dosage forms consist of semi-solid preparations such as creams, gels, ointments, ovules or suppository. However, these forms typically contain liquid phases which can promote physico-chemical instabilities of proteins during manufacturing and storage. Formulation of therapeutic antibodies into dry forms may therefore be highly preferable.
Among all available dosage forms, tablet is the most commonly used. This can be explained by its ease of administration, low production cost, stability and good patient compliance. Moreover, compared to other dosage forms, tablets offer numerous advantages such as precise dosing of the active substance, the ability to control and/or delay the release of the drug, and last but not least, tablet form can present an attractive opportunity for the local delivery of drugs, and more specifically mAbs, whether through buccal, gastrointestinal, rectal or vaginal mucosal administrations, with a time of exposure of mAbs to the mucosal surface that can be modulated.
Tablets are made by compressing a powder, which implies that the drug in solution form must undergo a prior drying process to attain a powdered state. For antibodies, the drying step is already well-established, with lyophilized powders making up 25 % of commercially available monoclonal antibody (mAb) formulations (Strickley and Lambert, 2021). Therefore, the freeze-drying process has been selected in this study as the method of choice to produce powder while preserving the bioactivity of the mAbs. In addition, previous works (Hsein et al., 2023, Madi et al., 2024) has demonstrated that freeze-dried powders present singular tableting properties specifically in terms of cohesion which reinforced our choice of freeze-drying to obtain the powder. However, the tableting process itself presents great challenges for the conservation of mABs activity. Actually, tableting process requires the application of high axial pressures resulting in mechanical stresses througout the compressed powder in order to generate cohesion between powder particles. The few studies carried out to examine protein compression have revealed that these stresses can potentially induce physical instabilities in proteins, leading to aggregation or conformational changes, which consequently have a detrimental effect on their biological activity (Klukkert et al., 2015, Wei et al., 2019).
Frijlink and his colleagues were the first to investigate the feasibility to develop mAb as a tablet pharmaceutical form (Gareb et al., 2019, Maurer et al., 2016). In these works, the tablets were manufactured from a FD powder obtained from the commercial product Remicade® (infliximab) within a glassy matrix of inulin. The primary objective of this study was not to explore the impact of the compression process on the antibody’s integrity. Only informations concerning the dry granulation step via slugging have been disclosed but no information about the tableting process parameters were given. Nevertheless, results suggest that, within the specified operational parameters, the tableting process did not have any detrimental effects on the antibody’s biological functions. No apparent alterations in the protein structure or loss in its binding capacity were observed compared to the original Remicade® formulation. The impact of tableting process on antibodies has also been recently studied (Lu et al., 2021). This study aimed to investigate the impact of various factors such as compaction pressure and particle size on antibodies integrity following compaction of a FD mixture of human polyclonal antibodies. Among the main results, this study revealed that high compression pressure (300 MPa) can lead to changes in the secondary structure of immunoglobulins. Furthermore, when studying the influence of compaction on the biological activity of these antibodies, it was demonstrated that their ability to bind to their antigenic target is adversely affected by compaction at both low and high compression pressures. Nonetheless, no correlation between pressure level and the impairment of antibody binding activity was identified.
Overall, these studies demonstrate the potential for developing therapeutic antibodies in tablet form. However, they suggest that both product and process parameters can negatively impact the integrity of antibodies. Nevertheless, their individual impacts have never been concurrently examined. Therefore, the aim of this study is to demonstrate the feasibility of manufacturing tablets using lyophilized powders incorporating monoclonal antibodies while preserving their physico-chemical and biological properties for local administration. For this purpose, the critical parameters of the product-process pairs during the tablet production of mAbs were further investigated. To this end, multiple variable including excipients, mAb quantity and compression pressure were simultaneously explored in order to identify the key parameters that may ensure the preservation of mAbs biological activity when compressed into tablet form.
Continue reading here
Materials
Trehalose dihydrate (Goch, Germany) and sucrose (Goch, Germany) were generously given by DFE pharma. Polysorbate 20 (Calbiochem®), phosphate buffer saline (PBS) (Euromedex), magnesium stearate (Cooper), Tubulin (from porcine brain, Cytoskeleton), Protein G (Genscript) and secondary Anti-Mouse IgG (H + L) antibody (Jackson Immuno Research) were purchased from their respective suppliers.
A STYL’One Evo compaction simulator by MEDELPHARM was used in the study.
Julie Auffray, Hassana Hsein, Nicolas Biteau, Christophe Velours, Thierry Noel, Pierre Tchoreloff, Development of monoclonal antibodies in tablet form: A new approach for local delivery, International Journal of Pharmaceutics, 2024, 124423, ISSN 0378-5173, https://doi.org/10.1016/j.ijpharm.2024.124423.
Read also the interesting article STYL’One Evo R&D – Scale-Up and Production Support here:
