Toward a Ferrous Iron-Cleavable Linker for Antibody-Drug Conjugates.
Mol Pharm
; 15(5): 2054-2059, 2018 05 07.
Article
in En
| MEDLINE
| ID: mdl-29569925
ABSTRACT
Antibody-drug conjugates (ADCs) are antigen-targeted therapeutics that employ antibodies to deliver potent, cytotoxic effectors to cells with potentially high specificity. While promising clinical results have been achieved, significant pitfalls remain including internalization of ADCs in nontargeted cells expressing target antigen, which can limit therapeutic windows. Novel ADC linkers that are cleaved selectively in cancer cells but not in normal cells could minimize collateral damage caused by ADC uptake in nontargeted tissues. Here, we describe a prototypical ADC linker based on an Fe(II)-reactive 1,2,4-trioxolane scaffold (TRX) that by itself has demonstrated tumor-selective activity in preclinical cancer models. We prepared TRX-linked ADCs by site-selective conjugation to two sites in trastuzumab and compared their activity in Her2 positive and negative cells to ADC controls based on established linker chemistry. Our results confirm that the TRX moiety efficiently releases its payload following ADC uptake, affording picomolar potencies in antigen-positive cells. We also identified a destabilizing interaction between these initial TRX linkers and nearby antibody residues and suggest an approach to improve upon these prototypical designs.
Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Immunoconjugates
/
Iron
/
Antibodies, Monoclonal
/
Antineoplastic Agents
Limits:
Animals
Language:
En
Journal:
Mol Pharm
Journal subject:
BIOLOGIA MOLECULAR
/
FARMACIA
/
FARMACOLOGIA
Year:
2018
Document type:
Article
Affiliation country:
United States
Publication country:
EEUU
/
ESTADOS UNIDOS
/
ESTADOS UNIDOS DA AMERICA
/
EUA
/
UNITED STATES
/
UNITED STATES OF AMERICA
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US
/
USA