SPDB-DM4 is primarily utilized in the development of antibody-drug conjugates (ADCs), which are a class of targeted cancer therapies. The compound serves as a potent cytotoxic agent that is linked to monoclonal antibodies, enabling the precise delivery of the drug to cancer cells. This targeted approach minimizes damage to healthy tissues, reducing side effects commonly associated with traditional chemotherapy. SPDB-DM4 is particularly effective in treating various cancers, including breast cancer, lymphoma, and leukemia, by inhibiting cell division and inducing apoptosis in malignant cells. Its application in ADCs represents a significant advancement in oncology, offering a more effective and less toxic treatment option for patients.