Phase 2, Single Arm Clinical Trial to Evaluate the Safety and Activity of Oregovomab and Niraparib as a Combinatorial Immune Priming Strategy in Subjects With Platinum Sensitive Recurrent Ovarian Cancer

• Subjects with CA125-associated recurrent epithelial adenocarcinoma of ovarian, fallopian tube or peritoneal origin.

• Subjects must have histologically diagnosed high-grade (Grade 2 or 3) serous epithelial ovarian, fallopian tube, or primary peritoneal cancer with recurrent disease and must have been previously treated with chemotherapy and experienced a response lasting at least 6 months to first-line platinum-based therapy.

• Previously treated disease with up to 3 prior lines of therapy, including at least one platinum-based therapy. Each line of therapy should have been changed due to recurrence, progression, or toxicity. Maintenance therapy with bevacizumab, hormonal therapies and / or a PARP inhibitor is not considered a line of therapy.

• Must have received prior platinum-based chemotherapy for first line ovarian cancer, however they must have been platinum sensitive for ≥6 months after the most recent platinum-containing regimen prior to the start of study treatment.

• Must have medical assessment consistent with prognosis for an expected survival of at least 6 months and be clinically appropriate to receive a 12-week hiatus from any cytotoxic treatment according to the best clinical judgement of the treating Investigator.

• Must have had an elevated serum CA125 \>50 units / mL measured at screening within 28 days of start of study treatment.

• Must have measurable disease, including identification of marker lesions, by radiographic or physical criteria suitable for evaluation according to RECIST v1.1 for documentation of disease response or progression.

• Must have an ECOG Performance Status of 0, 1 or 2.

• Must have adequate organ function defined as:

∙ Absolute neutrophil count ≥1,500 / μL

‣ Platelets ≥100,000 / μL

‣ Hemoglobin ≥9 g / dL

‣ Total bilirubin ≤1.5 x ULN (≤2.0 x ULN in subjects with known Gilberts syndrome) OR direct bilirubin ≤1 x ULN

‣ LDH, SGOT and SGPT\<2.5 x ULN

‣ Albumin \>3.5 g / dL

‣ Serum Creatinine \< 1.5 mg/dL

⁃ For women of childbearing potential, a negative pregnancy test and willingness to avoid pregnancy by using a highly effective method of contraception from the first dose of study treatment to 6 months after last dose of study treatment.

⁃ Able to take oral medications.

⁃ Sign informed consent and authorization permitting release of personal health information.