PDCD1 and small cell lung carcinoma: Another PARP inhibitor, Fluzoparib (also known as SHR-3162, manufactured by Jiangsu Hengrui Medicine Co Ltd., Lianyungang, China), is currently being evaluated in concert with an anti-PD-1 antibody in an open-label, phase II clinical trial (NCT04782089) in patients with ES-SCLC who did not improve after first-line chemotherapy.