SHANGHAI – Suzhou-based Cstone Pharmaceuticals Co. Ltd. is now a clinical-stage company with the dosing of its first Chinese patient with CS-1001, an anti-PD-L1 monoclonal antibody. In a full field of PD-1 antibodies, Cstone is betting CS-1001 will differentiate it as the first of its kind for China, a fully human and full length programmed cell death protein ligand 1 (PD-L1).