Target-responsive subcellular catabolism analysis for early-stage antibody-drug conjugates screening and assessment
Hua Sang1,2, Jiali Liu1, Fang Zhou1
1Jiangsu Provincial Key Laboratory of Drug Metabolism and Pharmacokinetics, State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing 210009, China.
Abstract:
Events including antibody‒antigen affinity, internalization, trafficking and lysosomal proteolysis combinatorially determine the efficiency of antibody-drug conjugate (ADC) catabolism and hence the toxicity. Nevertheless, an approach that conveniently identifies proteins requisite for payload release and the ensuing toxicity for mechanistic studies and quality assessment is lacking. Considering the plethora of ADC candidates under development, we developed a target-responsive subcellular catabolism (TARSC) approach that examines ADC catabolism and probes changes in response to targeted interferences of proteins of interest. We firstly applied TARSC to study the commercial T-DM1 and the biosimilar. We recorded unequivocal catabolic behaviors regardless of the absence and presence of the targeted interferences. Their negligible differences in TARSC profiles agreed with their undifferentiated anti-tumoral efficacy according to further in vitro viability and in vivo tumor growth assays, highlighting TARSC analysis as a useful tool for biosimilarity assessment and functional dissection of proteins requisite for ADC catabolism. Additionally, we employed TARSC to investigate the catabolic behavior of a new trastuzumab-toxin conjugate. Collectively, TARSC can not only characterize ADC catabolism at (sub)cellular level but also comprehensively determine which protein targets affect payload release and therapeutic outcomes. Future use of TARSC is thus anticipated in early-stage screening, quality assessment and mechanistic investigations of ADCs.
Insights
A new method called target-responsive subcellular catabolism (TARSC) analyzes antibody-drug conjugate (ADC) breakdown and toxicity. TARSC effectively assesses biosimilarity and identifies proteins crucial for ADC drug release and efficacy.
Area of Science:
- Biochemistry
- Pharmacology
- Molecular Biology
Background:
- Antibody-drug conjugate (ADC) catabolism, influenced by antibody-antigen affinity, internalization, trafficking, and lysosomal proteolysis, dictates efficacy and toxicity.
- Current methods for identifying proteins essential for ADC payload release and toxicity are insufficient for mechanistic studies and quality control.
Purpose of the Study:
- To develop and validate a novel approach, target-responsive subcellular catabolism (TARSC), for assessing ADC catabolism and identifying key proteins involved.
- To evaluate TARSC's utility in mechanistic studies, quality assessment, and biosimilarity evaluation of ADCs.
Main Methods:
- The target-responsive subcellular catabolism (TARSC) approach was developed to examine ADC catabolism by probing changes in response to targeted protein interference.
- TARSC was applied to a commercial ADC (T-DM1) and its biosimilar, and to a novel trastuzumab-toxin conjugate.
Main Results:
- TARSC revealed distinct catabolic behaviors for ADCs, unaffected by targeted protein interferences.
- TARSC profiles of T-DM1 and its biosimilar showed negligible differences, correlating with similar in vitro and in vivo anti-tumoral efficacy.
- The study successfully characterized ADC catabolism and identified protein targets influencing payload release and therapeutic outcomes using TARSC.
Conclusions:
- TARSC is a valuable tool for assessing ADC biosimilarity and dissecting the roles of proteins in ADC catabolism.
- TARSC provides a comprehensive method for characterizing ADC catabolism at the subcellular level.
- TARSC is anticipated for use in early-stage ADC screening, quality control, and mechanistic investigations.
