A Study of BBI608 in Combination With Sorafenib, or BBI503 in Combination With Sorafenib in Adult Patients With Hepatocellular Carcinoma

This is an open label, three-arm, phase 1 dose escalation study and phase 2 study of BBI608 in combination with sorafenib, or BBI503 in combination with sorafenib. The study population is adult patients with advanced hepatocellular carcinoma (HCC) who have not received systemic chemotherapy. The phase 1 portion will involve dose-escalation of BBI608 administered in combination with a fixed starting dose of sorafenib (Arm 1), and dose escalation of BBI503 administered in combination with a fixed starting dose of sorafenib (Arm 2). The fixed starting dose-level of sorafenib for both arms will be 400 mg twice daily (800 mg total daily dose). Eligible patients will be randomized to either Arm 1 or Arm 2. The phase 2 portion will be an open-label, 3-arm, randomized trial of patients with advanced HCC who have not received prior systemic treatment. Patients will be randomized to receive either, Arm 1: sorafenib administered in combination with BBI608 (at the RP2D determined for BBI608 plus sorafenib during the phase 1 portion); Arm 2: sorafenib in combination with BBI503 (at the RP2D determined for BBI503 plus sorafenib during the phase 1 portion), or Arm 3: sorafenib alone at a starting dose of 400 mg twice daily. The starting dose for sorafenib is the same for all study arms.