A phase 3 TAISHAN-302 trial reported that an anti-B7-H3 antibody-drug conjugate, Tam-Peli, reduced the risk of death by 54% versus topotecan in patients with relapsed small-cell lung cancer. The result positions Tam-Peli as a new contender for second-line treatment in a segment with limited durable options. If confirmed with additional endpoints and follow-up, the efficacy magnitude may accelerate how clinicians evaluate ADCs against chemotherapy standards in post-platinum settings. The readout also reinforces the broader ADC push into neuroendocrine tumors where B7-H3 expression and therapeutic targeting are emerging as differentiators.