Abstract 4396: Conjugation site modulates the stability and biological activity of antibody drug conjugates

Autor: Helga Raab, Kathryn Parsons, Mark X. Sliwkowski, Jagath Reddy Junutula, Kelly Flagella, Richard H. Scheller, Sunil Bhakta, Surinder Kaur, Luna Liu, Keyang Xu, Susan D. Spencer, Ben-Quan Shen, Paul Polakis
Rok vydání: 2010
Předmět:
Zdroj: Cancer Research. 70:4396-4396
ISSN: 1538-7445
0008-5472
Popis: Antibody drug conjugates (ADCs) are attractive targeted chemo-therapeutic molecules as they combine ideal properties of both antibodies and cytotoxic drugs by targeting potent cytotoxic drugs to the antigen-expressing tumor cells, thereby enhancing their anti-tumor activity. The successful ADC development for a given target antigen depends on optimization of antibody selection, linker stability, cytotoxic drug potency and mode of linker-drug conjugation to the antibody. Recently, we have developed antibodies with cysteine substitutions (THIOMABs) at sites where the engineered cysteines are available for conjugation but do not perturb immunoglobulin folding and assembly or alter antigen binding and effector functions (Junutula, et al., Nature Biotech., 26, 925-932, 2008). These THIOMABs can then be derivatized through the engineered cysteine thiol group to obtain ADCs with uniform stoichiometry (∼2 drugs per antibody). Studies with multiple antibodies against different antigens have shown that THIOMAB drug conjugates (TDCs) are as efficacious as conventional conjugates in xenograft models and are tolerated at higher doses in relevant preclinical models. To further understand improved therapeutic activity and in vivo metabolism of TDCs, we have engineered TDCs with drug attachment at different parts of the antibody (light chain-Fab, heavy chain-Fab and heavy chain-Fc). TDCs produced by THIOMAB technology provided an unique advantage over conventional ADCs to answer several unresolved questions in ADC therapeutics due to their homogeneity and site-specific conjugation to cytotoxic drugs. We will discuss novel findings that were observed with these TDC varaints and the influence of conjugation site in modulating stability and biological activity of antibody drug conjugates. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 4396.
Databáze: OpenAIRE