Trial watch: antibody-drug conjugates in cancer therapy

Antibody-drug conjugates (ADCs) combine the target specificity of monoclonal antibodies with the cytotoxic potency of small-molecule payloads. In recent years ADCs have emerged as a clinically validated component of modern precision oncology. To date, more than a dozen ADCs have received FDA approval for oncologic indications, with additional agents approved regionally and hundreds of ADC-based regimens in clinical development. Collectively, these therapies have demonstrated clinical benefit across hematologic malignancies and solid tumors, including significant overall survival improvements in advanced phase clinical trials. In this Trial Watch, we provide an overview on available ADCs from early preclinical development to current clinical applications. We also summarize design principles underpinning clinically successful ADCs, including epitope targeting, linker chemistry, payload toxicity and drug-to-antibody ratio, and discuss how these features can influence pharmacokinetics, intracellular trafficking, bystander effect and toxicity. Finally, we discuss results from advanced-stage clinical trials and approved agents to define future directions.