Single-step purification and formulation of antibody-drug conjugates using a miniaturized tangential flow filtration system

Antibody-drug conjugates (ADCs) are a promising therapeutic modality that enables the delivery of cytotoxic drugs to the target cells that express the corresponding antigen. However, the purification of ADCs while ensuring product safety, homogeneity, and stability is a challenging task due to their complex and fragile structure. Size exclusion chromatography (SEC), the conventional method for ADC purification, is time-consuming as it requires multiple column washes and equilibration steps. Moreover, subsequent formulation of ADCs, typically using dead-end filtration (DEF), further complicates the production workflow. We compared SEC+DEF with the µPulse®, a miniaturized and automated tangential flow filtration system, for purification and formulation of ADCs. Quality analysis revealed that both approaches were equally gentle as comparable drug-to-antibody ratios (DARs) and monomer purities were observed in the purified samples. Most importantly, both methods exhibited equivalent cleanup efficiency with a 99.8% reduction in free linker-drug concentration. The endotoxin loads comprised 0.11 EU mg^-1 for the µPulse and 0.07 EU mg^-1 for SEC+DEF, ensuring validation of the safe application of purified ADCs in living systems. However, the µPulse performed purification and formulation of ADCs simultaneously as compared to SEC+DEF, which required multiple manual interventions. Our results indicate that the µPulse is a gentle, single-step, and walk-away approach for the purification of ADCs.