FLX475 Combined With Pembrolizumab in Patients With Advanced or Metastatic Gastric Cancer

Prior treatment

• Prior therapy with an anti-PD-1, anti-PD-L1, or anti-PD-L2 agent or an agent directed to another stimulatory or co-inhibitory T-cell receptor (e.g., CTLA-4, OX-40, CD137), any history of discontinuing from that treatment due to Grade 3 or higher immune-related adverse event (irAE)
• Has had an allogenic tissue/solid organ transplant

Other illness

• Active autoimmune disease or serious autoimmune disease within past 2 years requiring systemic therapy
• History of idiopathic pulmonary fibrosis, organizing pneumonia, drug-induced pneumonitis, idiopathic pneumonitis, (non-infectious) pneumonitis that required steroids, or clinical symptoms of active pneumonitis
• Significant cardiovascular disease. New York Heart Association (NYHA) Class 3 or 4 congestive heart failure, or chronic Grade 3 hypertension.

Other

• Patient with MSI-H status
• Significant screening electrocardiogram (ECG) abnormalities

• All patients must have histologically or cytologically confirmed, advanced, relapsed or metastatic gastric or gastroesophageal junction adenocarcinoma
• Patient must have one of the following diagnoses to be eligible for enrollment into cohorts:
  • Cohort 1: Checkpoint inhibitor naïve Epstein-Barr Virus negative (EBV-) gastric cancer patient who has had a disease progression after at least 2 prior systemic treatments for advanced or metastatic gastric cancer
  • Cohort 2: Checkpoint inhibitor naïve Epstein-Barr virus positive (EBV+) gastric cancer patient (as determined by standard methods, e.g. EBER ISH or LMP-1 IHC) who had at least 1 prior systemic treatment for advanced or metastatic gastric cancer
• Eastern Cooperative Oncology Group (ECOG) Performance Status 0-1
• Patient must have at least one measurable lesion at baseline by computed tomography(CT) or magnetic resonance imaging (MRI)
• Tumor available for biopsy