Subvisible Particle Analysis of 17 Monoclonal Antibodies Approved in China Using Flow Imaging and Light Obscuration

A Novel Size Exclusion Chromatography Method for the Analysis of Monoclonal Antibodies and Antibody-drug Conjugates by Using Sodium Iodide in the Mobile Phase

PURPOSES

Size exclusion chromatography (SEC) is widely used to characterize molecular size variants of antibody drugs. However, SEC analysis is hindered by secondary interactions (or nonspecific interactions) between proteins and stationary phase packing, which result in poor column efficiency. Previous studies have reported that chaotropic salt can inhibit these interactions, but the corresponding applications of this aspect are relatively rare. Therefore, this study introduces a novel approach using sodium iodide (NaI) as a mobile-phase component in SEC and investigates the influence of the mobile-phase composition on secondary interactions.

METHODS

SEC analysis was performed on one antibody-drug conjugate and four monoclonal antibodies (mAbs) using three different mobile-phase systems (i.e., sodium chloride/L-arginine hydrochloride/NaI mobile phases system) to compare the column efficiency. Subsequently, mAb-1 was used as a model to investigate the effects of these factors on secondary interactions by adjusting the ionic strength (salt concentration) and pH of the NaI mobile-phase system.

RESULTS

NaI exhibits superior column efficiency performance in the SEC analysis of most products. The ionic strength will affect nonideal electrostatic and hydrophobic interaction. An appropriate ionic strength can inhibit electrostatic interactions, while an excessive ionic strength increases hydrophobic interactions. pH primarily influences electrostatic interactions. Determining the appropriate pH necessitates consideration of the isoelectric point of the protein and the pH tolerance of the column.

CONCLUSIONS

In SEC analysis, using NaI as the salt component in the mobile phase reduces secondary interactions and improves column efficiency. This approach is advantageous for samples with intense secondary interactions and is a suitable alternative.

Intranasal delivery of thin-film freeze-dried monoclonal antibodies using a powder nasal spray system

Monoclonal antibodies (mAbs) administered intranasally as dry powders can be potentially applied for the treatment or pre-exposure prevention of viral infections in the upper respiratory tract. However, a method to transform the mAbs from liquid to dry powders suitable for intranasal administration and a device that can spray the dry powders to the desired region of the nasal cavity are needed to fully realize the potentials of the mAbs. Herein, we report that thin-film freeze-dried mAb powders can be sprayed into the posterior nasal cavity using Aptar Pharma's Unidose (UDS) Powder Nasal Spray System. AUG-3387, a human-derived mAb that neutralizes the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), was used in the present study. First, we prepared thin-film freeze-dried AUG-3387 powders (i.e., TFF AUG-3387 powders) from liquid formulations containing different levels of mAbs. The TFF AUG-3387 powder with the highest solid content (i.e., TFF AUG-3387C) was then chosen for further characterization, including the evaluation of the plume geometry, spray pattern, and particle size distribution after the powder was sprayed using the UDS Powder Nasal Spray. Finally, the deposition patterns of the TFF AUG-3387C powder sprayed using the UDS Powder delivery system were studied using 3D-printed nasal replica casts based on the CT scans of an adult and a child. It is concluded that it is feasible to intranasally deliver mAbs as dry powders by transforming the mAbs into dry powders using thin-film freeze-drying and then spraying the powder using a powder nasal spray system.

Evaluation of subvisible particles in human immunoglobulin and lipid nanoparticles repackaged from a multi-dose vial using plastic syringes

The multi-dose vial (MDV) is widely used for most biopharmaceuticals that are repackaged in plastic syringes before use. However, subvisible particle formation with the use of plastic syringes containing silicone oil (SO syringes) for handling therapeutic proteins can be problematic. This study aimed to evaluate the extent of and trends in microparticle (>1 μm) formation and accumulation in repackaged syringes from MDVs containing human immunoglobulin (IgG) and lipid nanoparticles (LNPs). Light obscuration (LO) and flow imaging (FI) were used to analyze the microparticles. The number of microparticles observed with the use SO syringes was greater than that with SO-free syringes, and the number of microparticles continuously increased as did the number of times of repackaging in syringes for both drugs. However, a large variation was observed across different brands of SO syringes. In contrast, using a different technique of drug withdrawal from the vial significantly reduced the number of microparticles. Furthermore, the use of filter-integrated needles or the inclusion of stabilizers such as acetyl-arginine and Tween 20 into the formulation also helped reduce particle formation.