An anti-GD2 antibody–drug conjugate (ADC) that binds the GD2 ganglioside on tumor cells, is internalized, and releases an exatecan-based topoisomerase I inhibitor payload, leading to TOP1 inhibition, DNA damage, replication stress, and tumor cell death. Evaluated in GD2-positive soft tissue sarcomas and IDH-wildtype glioblastoma to establish MTD/RP2D, safety, and preliminary activity.