Current approaches for the purification of antibody–drug conjugates

Abstract

In the past two decades, antibody-drug conjugates have gained increasing attention because they expand the therapeutic index when compared with that of traditional chemotherapies. Antibody-drug conjugates are highly complex structures consisting of antibodies covalently conjugated with small-molecule cytotoxic drugs. The complex structure of antibody-drug conjugates makes chemistry, manufacturing, and control difficult. In contrast to antibody production, distinct purification methods following conjugation of antibodies with druglinkers are required for the manufacturing. For process development of antibody drug conjugates, the drug-to-antibody ratio, free drug-linkers, and aggregates are critical quality attributes that must be strictly controlled and removed by appropriate purification techniques. In this review, features of various purification methods used to purify antibody drug conjugates are described and evaluated. The future landscape of the antibody-conjugates field is also discussed briefly.

Chemical Site-Specific Conjugation Platform to Improve the Pharmacokinetics and Therapeutic Index of Antibody–Drug Conjugates

“…Removal of the peptide portion of ( 1 ) via tris-(2-carboxyethyl)-phosphine hydrochloride (TCEP)-mediated reduction and concomitant antibody interchain disulfide bond cleavage followed by oxidation using dehydroascorbic acid (DHAA) under mild conditions to reform the reduced interchain disulfide bridges provided the site-specifically thiol-modified trastuzumab ( 3A ). All purification steps to remove impurities, including peptide-related fragments, were carried out straightforwardly utilizing tangential flow filtration, a well-known technique that enables facile scale-up and future translation to kilogram-scale ADC preparations in a manufacturing facility . To examine the reactivity of the installed thiol groups, drug-linkers MCC-maytansinoid and MC-VC-MMAE (their chemical structures described in Figure S1 in the Supporting Information) were reacted with 3A to produce two ADCs, and the respective DARs were determined by quadrupole time-of-flight mass spectrometry (Q-TOF MS).…”

Biological Evaluation of Maytansinoid-Based Site-Specific Antibody-Drug Conjugate Produced by Fully Chemical Conjugation Approach: AJICAP®

“…This reaction completion was detected by IPC analysis using HIC HPLC, as per a previous good laboratory practice (GLP) material preparation [13]. Purification to remove residual drug linkers was performed in a straightforward manner using tangential flow filtration (TFF), which is a commonly used technique that can be applied to kilogramscale ADC manufacturing [21,22]. Compared to MC-VC-MMAE, which was previously used for preparing AJICAP-ADC, TFF could clear MCC-maytansinoid from the ADC composition.…”

Rapid antibody conformational screening by matrix‐assisted laser desorption/ionization hydrogen‐deuterium exchange mass spectrometry

“…Prior to this work, our group had not performed HDX on intact antibodies or sought to validate our SEC-HDX system for these large molecules. SEC has been used routinely for the assessment of ADCs, bsABs, and mABs [4]. Additionally, intact labeling of antibodies typically yields large mass gains in deuteration.…”

“…Advances in the fundamental understanding of immunology and oncology have afforded several new modalities to effectively address various types of cancers, with antibodydrug conjugates (ADCs), bispecific antibodies (BsAbs), and monoclonal antibodies (mAbs) comprising an everexpanding share of the promising new therapies being developed within the pharmaceutical field [1][2][3][4]. Typically, mammalian expression systems, such as Chinese hamster ovary (CHO) cells, are used for antibody production.…”