RecruitingPhase 2Drug trialKN046 Plus Regorafenib or Apatinib in MSI-H Digestive System Cancers Resistant to PD-1/PD-L1 BlockadeThe study is an interventional phase II clinical trial aiming to evaluate the efficacy and safety of KN046, a PD-L1 and CTLA-4 bispecific antibody, in combination with regorafenib or apatinib for microsatellite instability-high digestive system cancers resistant to PD-1/PD-L1 blockade. KN046 plus regorafenib will be given for patients with colorectal cancers, and KN046 plus apatinib will be given for patients with gastric cancers (including esophageal-gastric junction cancers) and other kinds of digestive system cancers.