Pembrolizumab and Lenvatinib for the Treatment of Advanced, Unresectable, or Metastatic Gastroesophageal Adenocarcinoma

The subject (or legally acceptable representative if applicable) provides written informed consent for the trial

Male and female subjects who are at least 18 years of age on day of signing informed consent with histologically and cytologically documented diagnosis as gastric or gastroesophageal adenocarcinoma

Has a documented, previously treated, advanced (unresectable and/or metastatic) gastroesophageal adenocarcinoma that is incurable and for which prior first-line or later-line standard of care (SOC) treatments have failed. Prior neoadjuvant or adjuvant therapy included in initial treatment may not be considered first- or later-line SOC treatment unless such treatments were completed less than 12 months prior to the current tumor recurrence

Has submitted an evaluable tissue sample for biomarker analysis from a newly obtained irradiated. The tumor tissue submitted for analysis must be from a single tumor tissue specimen and of sufficient quantity and quality to allow biomarker study (see laboratory manual). A "newly obtained" tumor specimen, defined as a specimen obtained up to 6 weeks (42 days) prior to initiation of treatment on day 1, for biomarker characterization will be required for enrollment of all subjects. Tissue from tumor progressing at a site of prior radiation (at least 6 weeks interval after last radiation) may be allowed for biomarker characterization upon agreement from Merck. Subjects for whom newly-obtained samples cannot be provided (e.g., inaccessible or subject safety concern) may submit an archived specimen only upon agreement from the Merck