Optimization of Tubulysin Antibody–Drug Conjugates: A Case Study in Addressing ADC Metabolism

Autor: Judy Lucas, Guoyun Bai, Christopher J. O’Donnell, Sai Chetan K. Sukuru, Brian Rago, Sarah P. Hudson, Carolyn A. Leverett, Lioudmila Tchistiakova, Edmund I. Graziani, Anokha S. Ratnayake, Sylvia Musto, Jeffrey M. Casavant, Joseph Stock, Frank Loganzo, Christine Hosselet, Sujiet Puthenveetil, Andrew J. Bessire, Fengping Li, Xiaogang Han, Tracey Clark, Venkata Doppalapudi, Kimberly Ann Marquette, Beth C. Vetelino, Chakrapani Subramanyam, L. Nathan Tumey
Rok vydání: 2016
Předmět:
Zdroj: ACS Medicinal Chemistry Letters. 7:977-982
ISSN: 1948-5875
Popis: As part of our efforts to develop new classes of tubulin inhibitor payloads for antibody-drug conjugate (ADC) programs, we developed a tubulysin ADC that demonstrated excellent in vitro activity but suffered from rapid metabolism of a critical acetate ester. A two-pronged strategy was employed to address this metabolism. First, the hydrolytically labile ester was replaced by a carbamate functional group resulting in a more stable ADC that retained potency in cellular assays. Second, site-specific conjugation was employed in order to design ADCs with reduced metabolic liabilities. Using the later approach, we were able to identify a conjugate at the 334C position of the heavy chain that resulted in an ADC with considerably reduced metabolism and improved efficacy. The examples discussed herein provide one of the clearest demonstrations to-date that site of conjugation can play a critical role in addressing metabolic and PK liabilities of an ADC. Moreover, a clear correlation was identified between the hydrophobicity of an ADC and its susceptibility to metabolic enzymes. Importantly, this study demonstrates that traditional medicinal chemistry strategies can be effectively applied to ADC programs.
Databáze: OpenAIRE