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). The company has gone from zero to entering the clinic at a blistering pace. It was just over a year ago when Cstone made a splash, raising an eye-catching $150 million in series A financing – a record for China. The firm also attracted well-known pharma executives such as Frank Jiang, former Asia Pacific R&D head for Sanofi SA.