Used in antibody-drug conjugates (ADCs) as a cleavable linker to connect cytotoxic drugs to monoclonal antibodies. Enables targeted delivery of chemotherapy to cancer cells by leveraging the specificity of antibodies. The linker remains stable in circulation but releases the active drug inside tumor cells upon internalization and lysosomal degradation. Particularly effective in enhancing therapeutic index by minimizing off-target toxicity while maximizing drug concentration at the tumor site. Widely applied in oncology drug development for cancers such as leukemia, lymphoma, and solid tumors.