A Study Combining the Peposertib (M3814) Pill With Standard Chemotherapy in Patients With Ovarian Cancer With an Expansion in High Grade Serous Ovarian Cancer and Low Grade Serous Ovarian Cancer

Inclusion Criteria: * DOSE ESCALATION PHASE: Women with recurrent or persistent epithelial ovarian, fallopian tube or primary peritoneal cancer are eligible. This includes, but is not limited to, the following histologic types: serous adenocarcinoma (grade 1,2, or 3/ high grade or low grade), endometrioid adenocarcinoma, carcinosarcoma, mucinous adenocarcinoma, undifferentiated carcinoma, clear cell adenocarcinoma, mixed epithelial adenocarcinoma, transitional cell carcinoma, or adenocarcinoma not otherwise specified * NOTE: Patients who have evidence of DDR deficiency /HRD are eligible if they are at the point in their disease course where they are appropriate candidates for single agent Doxil * EXPANSION PHASE: The expansion phase will simultaneously accrue to 2 cohorts, low grade serous ovarian cancer (LGSOC) and high grade serous ovarian cancer (HGSOC) * Patients accrued to the LGSOC cohort will have recurrent or persistent low grade serous ovarian cancer or grade 1 serous ovarian cancer * Patients accrued to the HGSOC cohort will have recurrent or persistent high grade serous ovarian cancer * Patients must have measurable disease by defined Response Evaluation Criteria in Solid Tumors (RECIST) 1.1 criteria * Prior therapy: * Patients must have received at least one prior line of platinum-based chemotherapy * Patients can have received an unlimited number of additional lines of chemotherapy, targeted therapy, biologic therapy, or hormonal therapy * Any pri…