Toripalimab and JS004 Combined With Platinum-based Chemotherapy for Relapsed and Extensive-stage Small Cell Lung Cancer

For extensive-stage small cell lung cancer (SCLC), platinum-chemotherapy (cisplatin or carboplatin) combined with etoposide as the first-line treatment is recommended. However, the recurrence rate is extremely high after the initial first-line treatment. For those who relapse or progress within more than six minths after the end of the-first-line treatment, chose the current guideline recommendation trearment plan has the poor prognosis. A new immunotherapeutic strategy is needed to achieve better anti-tumor effects. JS004 is a new antibody targeting B and T lymphocyte attenuator (BTLA), which restrains immune cells; function and leads to immune escape of tumor cells. The combination of PD-1 and BTLA antibodies has shown a good therapeutic effect in solid tumors. This trial aims to investigate the efficacy and safety of the therapeutic regimen of toripalimab and JS004 combined with platinum-based doublet chemotherapy in extensive-stage SCLC or relapsed within more than six months after radical treatment SCLC.