Antibody-drug conjugates in solid tumors: a new frontier.

Purpose of review: Antibody-drug conjugates (ADCs) are designed to carry cytotoxic payloads and deliver them to specific molecular targets within tumor cells. Several ADCs are already approved with many more in development across several disease types. In this review, we will provide an overview of the ADCs currently approved and those under investigation in solid tumors.

Recent findings: Currently there are dozens of ADCs under clinical study evaluation of a variety of solid tumors, and preliminary results are promising. Multiple ADCs have received regulatory approval in disease such as breast cancer, non-small cell lung cancer, and bladder cancer. While some are approved in biomarker selected settings with disease specific indication (e.g. breast cancer), others have been approved irrespective of biomarker expression (urothelial carcinoma) and pan-cancer indications in biomarker selected patients (HER2 3+ expression).

Summary: Cytotoxic chemotherapy has been the mainstay of systemic treatment for patients with various solid tumors. ADCs offer the advantage of carrying the cytotoxic payload onto a specific molecular receptor, thereby inducing a more selective response. Optimizing selection of target antigen, payload delivery and investigating biomarkers of response will be crucial for further expanding the therapeutic benefit of ADCs across solid tumors.