This is an open label, single group, non-randomized, phase I study with cohort expansion that utilizes the standard 3+3 design for dose. The dose of selinexor will be escalated in combination with the standard doses of irinotecan. The maximum tolerated dose (MTD) for study is defined as the highest dose level at which 1 or less of 6 patients experience a dose limiting toxicity DLT.~Once the MTD is reached and/or the recommended dose for expansion is determined, an additional cohort of 15 patients with advanced gastric or esophageal cancer will be accrued to better define the safety and tolerability of the combination regimen.
The main purpose of this study is to see whether the combination of selinexor (KPT-330) and irinotecan can help people with esophageal or stomach cancer. Researchers also want to find out if the combination of selinexor (KPT-330) and irinotecan is safe and tolerable.