Nature | Modular in vivo antibody–ADC click to reverse drug resistance in tumours

This study provides a novel in vivo assembly strategy to address the challenges of tumor heterogeneity and drug resistance. It suggests that orthogonal chemical approaches can be explored in drug development to overcome single-target limitations and optimize the delivery efficiency of antibody-drug conjugates (ADCs).

 

Literature Overview

This paper, titled 'Modular in vivo antibody–ADC click to reverse drug resistance in tumours' and published in Nature, systematically explores a modular antibody-drug conjugate (ADC) construction platform based on an in vivo bioorthogonal ligation strategy. The platform aims to address the limitations and drug resistance of traditional ADC therapies, which often rely on the high expression of a single antigen.

Background Knowledge

The primary challenge in current cancer therapy lies in the high heterogeneity of tumors, which prevents single-target ADCs from uniformly covering all tumor cells and leads to drug resistance due to antigen loss or low expression. Although targets such as HER2 and EGFR are expressed in various tumors, their spatial distribution within tumor tissues often does not overlap, and low-expression or negative regions exist, limiting the universality of existing therapies. Furthermore, traditional bispecific antibodies or antibody combination therapies face difficulties in achieving synergistic distribution in vivo and often require complex antibody engineering modifications. This study leverages bioorthogonal chemistry to modify antibodies targeting different antigens and ADCs with specific reactive groups, enabling the in situ assembly of functional complexes within the body. This approach utilizes receptor biological characteristics to enhance drug uptake and internalization in heterogeneous tumors without the need for extensive redesign of the antibody scaffold.

 

 

Research Methods and Core Experiments

The authors constructed heterogeneous tumor models expressing both HER2 and EGFR, including bilateral xenograft models (one side with high HER2 expression, the other with ultra-low HER2 but high EGFR expression). Clinically approved antibodies (e.g., Panitumumab) and ADCs (e.g., T-DXd, T-DM1) were conjugated with trans-cyclooctene (TCO) and tetrazine (Tz) groups, respectively. In vivo orthogonal click reactions facilitated the in situ ligation of antibodies and ADCs in the bloodstream or locally within tumors. PET-CT imaging was used to track the in vivo distribution of radiolabeled antibodies, while immunofluorescence, live-cell imaging, and Western Blot techniques verified the binding, internalization, and lysosomal targeting capabilities of the click complexes on the cell surface.

Key Conclusions and Perspectives

• In vivo click reactions significantly increased the uptake of HER2-targeted ADCs in HER2-low or HER2-negative but EGFR-high tumor cells, enhancing uptake by approximately 3.2-fold, thereby demonstrating the feasibility of using co-expressed antigens for assisted delivery.
• The click-formed antibody-ADC complexes enhanced the internalization rate of HER2 receptors and lysosomal trafficking, enabling effective release of cytotoxic payloads even at low antigen expression levels.
• This strategy significantly inhibited tumor growth and extended survival in HER2-low and HER2-ultralow breast and pancreatic cancer models, overcoming the drug resistance bottleneck of traditional single-agent ADC therapy.
• Through site-specific conjugation technology, non-specific liver accumulation was further reduced, improving the pharmacokinetic properties and batch-to-batch consistency of the drug, laying the foundation for clinical translation.
• This modular platform is highly scalable and can be applied to other receptor pairs (e.g., PD-L1, PSMA), offering a universal strategy to address heterogeneity and drug resistance in different tumor types.

Research Significance and Prospects

This discovery has profound implications for drug development, demonstrating that in vivo chemical assembly strategies can bypass the limitations of traditional antibody engineering to flexibly address tumor heterogeneity. In terms of clinical monitoring, this strategy may provide new treatment opportunities for patients previously excluded from existing ADC therapies due to insufficient antigen expression levels. Furthermore, this study offers new insights for disease modeling, emphasizing the need to fully consider the spatial distribution and synergistic effects of multiple targets within the tumor microenvironment when evaluating drug efficacy, rather than focusing solely on the expression level of a single target.

 

 

Conclusion

By introducing in vivo bioorthogonal click chemistry, this study successfully constructed a modular antibody-drug conjugate delivery system that effectively addresses the core bottlenecks of tumor heterogeneity and drug resistance in traditional ADC therapies. This strategy, without requiring complex antibody re-engineering, utilizes co-expressed antigens on the tumor surface (such as EGFR) as a 'navigation' system to precisely deliver HER2-targeted cytotoxic drugs to low-expression or previously unrecognizable tumor regions. From the perspective of translating from the laboratory to the clinic, this technology is expected to significantly expand the indications of existing ADC drugs, particularly for refractory diseases such as HER2-low and HER2-negative breast and pancreatic cancers. By optimizing site-specific conjugation, the platform further enhances drug safety and reproducibility, laying a solid foundation for the future development of multi-target synergistic therapeutic strategies for complex microenvironments, marking a significant step forward in precision oncology towards greater flexibility and efficiency.

 

Cristina Simó, Alexander C Vanover, Ricardo D'Oliveira Albanus, Farrokh Dehdashti, and Patrícia M R Pereira. Modular in vivo antibody–ADC click to reverse drug resistance in tumours. Nature.