T-regulatory Cell Depletion With E7777 Combined With Pembrolizumab in Recurrent or Metastatic Solid Tumors

Epithelial ovarian cancer (OC) is the most lethal gynecologic cancer: nearly 22,000 women are diagnosed with OC in the US annually and 63% are expected to die from their disease. The 5-year overall survival rate is unacceptably low at 20-30%, with \> 50% of patients experiencing recurrence of their disease. Recurrent, platinum-resistant OC is characterized by a low response to chemotherapy (\<10-15%) and poor prognosis, with overall survival estimated to be \<12 months. Thus, there is an urgent need to identify novel therapies to improve outcomes for patients with recurrent, platinum resistant OC. The primary focus in this trial is targeting tumor associated immunosuppressive T-regs with E7777 combined with PD-1 inhibitor, pembrolizumab. This trial will enroll patients with solid tumors in the dose escalation portion and specified cohorts in the dose expansion portion. In the Phase I portion, 18-30 patients will be enrolled. In the dose expansion portion, approximately 40 patients (20 in each cohort) will be enrolled. Given the relatively poor prognosis and limited treatment options for these patients, this population is considered appropriate for trials of novel therapeutic candidates.