CStone Pharmaceuticals (CStone; HKEX: 2616) has received approval to start clinical development of CS1001 in combination with BLU-554 (CS3008) in China in patients with locally advanced or metastatic hepatocellular carcinoma (HCC), it was reported yesterday.

The trial is a multi-centre, open-label, and multi-dose Phase Ib/II study that intends to assess the safety, tolerability, pharmacokinetics, pharmacodynamics, and anti-tumour efficacy of the combination in advanced HCC.

CS1001 is a proprietary anti-PD-L1 monoclonal antibody developed by the company, and one of the company's three backbone immuno-oncology products. Presently, CS1001 is being investigated for the treatment of lung cancer, gastric cancers, and other advanced malignancies. In a Phase Ia study, CS1001 was well-tolerated and showcased anti-tumour activity with partial responses observed in various tumour types.

The US Food and Drug Administration has granted orphan drug designation to BLU-554 for the treatment of HCC.