抗体製剤（Antibody Formulation）とは？

Antibody formulation refers to the process of optimizing antibody solutions or suspensions to ensure stability, potency, and safety. This is particularly important if the applications are as therapeutic agents, in order to control the rate of antibody degradation and maximize shelf life for global shipping and storage.¹

A common antibody formulation includes an antibody, excipient, lyoprotectant, buffer, and surfactant. These formulations may be classified as intravenous or subcutaneous, as well as a solution or lyophilized powder as the administration route.² The formulation should also take into account any potential immune responses, in addition to preserving antibody activity.  

• Antibody (Active Ingredient): The biologically active component targeting specific disease markers. 

• Excipients: Inactive ingredients such as sugars (sucrose, trehalose) that stabilize the antibody’s structure. 

• Lyoprotectants: Protect the antibody during freeze-drying in lyophilized formulations, which are reconstituted before use. 

• Buffers: Control pH, preserving antibody structure and stability. 

• Surfactants: Prevent aggregation and stabilize the antibody during production and storage (e.g., polysorbate 80). 

These components are carefully balanced to maintain antibody stability in solution or powder form, considering specific storage, shipping, and administration needs.

Formulation Types 

Antibody formulations vary based on administration route and physical state: 

• Intravenous (IV) vs. Subcutaneous (SC): IV formulations allow larger doses, typically administered in clinical settings. SC formulations, optimized for smaller, concentrated doses, enable self-administration. 

• Solution vs. Lyophilized Powder: Liquid solutions are ready-to-use but require strict storage controls, whereas lyophilized powders increase shelf life and stability, especially for global distribution. 

Strategies for Stability and Immunogenicity Reduction 

• Aggregation Control: Aggregation, which can reduce efficacy and increase immunogenicity, is minimized with excipients like trehalose and polysorbates. 

• Oxidation Prevention: Antioxidants such as methionine and low-oxygen packaging help limit oxidation, which degrades antibody structure. 

• Buffer Selection: Optimal pH stabilizes antibodies, typically between 5.0 and 7.0. 

• Lyophilization with Lyoprotectants: Freeze-drying reduces water content and slows degradation, with trehalose aiding structural preservation during reconstitution. 

These strategies, alongside rigorous purification, help ensure the safety and effectiveness of antibody formulations by reducing degradation and minimizing immune responses in patients. 

References:  

1. Wang, W., Singh, S., Zeng, D. L., King, K., & Nema, S. (2007). Antibody structure, instability, and formulation. Journal of Pharmaceutical Sciences, 96(1), 1-26. https://doi.org/10.1002/jps.20727

2. Strickley, R. G., & Lambert, W. J. (2021). A review of Formulations of Commercially Available Antibodies. Journal of Pharmaceutical Sciences, 110(7), 2590-2608.e56. https://doi.org/10.1016/j.xphs.2021.03.017