Blocking antibodies targeting PD-1 have achieved remarkable results in the treatment of many
      types of tumors. However, it is also worth noting that this therapeutic strategy typically
      achieves a < 30% objective response rate (ORR) as a monotherapy in patients whose tumors
      exhibit low positive PD-L1 expression and/or are microsatellite stable. TIM-3 and PD-1
      function as immune checkpoint receptors in the overlapping regulation of immune tolerance and
      have been shown to be overexpressed on the tumor infiltrating lymphocytes (TILs) from patient
      samples of various solid tumors including, but not limited to non-small cell lung cancer,
      head and neck squamous cell carcinoma, hepatocellular carcinoma, and gastric carcinoma.
      Subsequently, the activation of TIM-3 and PD-1 represent TILs from both patients or animals
      across solid tumor types with the most exhausted immunophenotype (ie, cytokine expression,
      proliferation etc.), which can be reversed with combined blockade of TIM-3 and PD 1. The
      overlap in expression and function indicates that TIM-3 and PD-1 cooperate to promote
      effector cell exhaustion which may impede an effective antitumor immune response. Based upon
      the overlapping expression profiles and immuno-regulatory functions, the improved in vivo
      antitumor effects, as well as the potential for TIM-3 mediated adaptive resistance, there is
      strong scientific rationale to evaluate the antitumor effects derived from the combined
      blockade of TIM-3 and PD-1 in advanced solid tumors. Accordingly, this study will evaluate
      the safety and preliminary efficacy of BGB-A425 (anti TIM-3) in combination with tislelizumab
      (anti PD-1) in patients with advanced solid tumors.

      This is an open-label, multicenter, nonrandomized Phase 1 and Phase 2 clinical trial. Phase 1
      will determine the Recommended Phase 2 Dose (RP2D) for the combination of BGB-A425 and
      tislelizumab. Phase 2 will continue to evaluate the safety but also focus on the efficacy of
      the combination in select tumor types.