CD274 and small cell lung carcinoma: LB100 and carboplatin combination treatment resulted in significantly smaller tumor size in xenograft SCLC mice than controls (P < 0.001). LB100 administration also increased carboplatin uptake in tumor cells (P < 0.001). Triple therapy with LB100, the PD-1 inhibitor atezolizumab, and anti-PD-L1 starkly destroyed H446 SCLC tumor cell spheroids, increased infiltration by activated T cells, and increased tumor cell death in vitro.