The purpose of this study is to compare the overall survival of patients treated with VTX-2337 + pegylated liposomal doxorubicin (PLD) versus those treated with PLD alone in women with recurrent or persistent, epithelial ovarian, fallopian tube or primary peritoneal cancer.

VTX-2337, a small molecule agonist of Toll-like Receptor 8 (TLR8), activates multiple components of the innate immune system and is being developed as a novel therapeutic agent for use in oncology. Experimental data obtained in an animal model of ovarian cancer supports the combination of VTX-2337 with PLD. In this model, the combination of VTX-2337 and PLD resulted in a significant reduction in tumor growth compared to either agent alone and an increase in the number of T lymphocytes infiltrating the tumor. The combination of PLD and VTX-2337 has been tested in a small number of women with ovarian cancer in a Phase 1b study and appears to be generally well-tolerated.

OBJECTIVES

Primary Objectives:

• To compare the overall survival (OS) of patients treated with VTX-2337 + PLD versus those treated with PLD alone in women with recurrent or persistent, epithelial ovarian, fallopian tube or primary peritoneal cancer.
• To compare the progression-free survival (PFS) between the two treatment groups using Immune-Related Response Evaluation Criteria in Solid Tumors (irRECIST).

Secondary Objectives:

• To compare the progression-free survival (PFS) between the two treatment groups using Response Evaluation Criteria In Solid Tumors (RECIST 1.1).
• To compare the nature, frequency and severity of drug-related adverse events (AEs) between the two treatment groups.

Exploratory Objectives:

• To compare the best overall response rate (ORR) and duration of response (based on the probability of being in response function [PBRF]) between the two treatment groups using irRECIST and RECIST 1.1.
• To compare the disease control rate (DCR) between the two treatment groups using irRECIST and RECIST 1.1.
• To assess the impact of immune status and response on the clinical effects (OS, PFS, DCR, ORR, PBRF, AEs) of study treatment.
• To assess the effect of TLR8 polymorphisms and BRCA1/BRCA2 mutations on the clinical effects (OS, PFS, DCR, ORR, PBRF, AEs) of study treatment.
• To assess the effect of immune cell subsets, as measured by immunohistochemistry and micro RNA in primary tumor tissue (e.g. immune score), on the clinical effects (OS, PFS, DCR, ORR, PBRF, AEs) of study treatment.
• To assess whether the presence of autoantibodies to tumor-derived proteins are predictive of the clinical effects (OS, PFS, DCR, ORR, PBRF, AEs) of study treatment.

OUTLINE:

This is Phase 2 multicenter clinical study to evaluate the efficacy and safety of the combination of VTX-2337 + PLD compared to PLD + Placebo.

The dosing schedule will be the same for both treatment arms, and will be based on a 28-day cycle. The starting dose schedule is PLD on Day 1 plus VTX-2337 or placebo on Day 3, Day 10, and Day 17 for the first 4 cycles. Starting with cycle 5, the dose regimen will be PLD on Day 1 plus VTX-2337 or placebo on Day 3.

Blood samples are collected periodically during cycle 1 for pharmacodynamics, pharmacogenomics, and other research studies.

Patients will receive therapy until disease progression based on Immune-Related RECIST or until adverse effects prohibit further therapy. Following treatment completion, all patients will be followed with physical exams and histories every three months for the first two years, and then every six months for the next three years, and then

Inclusion Criteria:

1. Patients must have recurrent or persistent epithelial ovarian, fallopian tube, or primary peritoneal carcinoma.

2. Patients with the following histologic cell types are eligible: serous adenocarcinoma, endometrioid adenocarcinoma, mucinous adenocarcinoma, undifferentiated carcinoma, clear cell adenocarcinoma, mixed epithelial adenocarcinoma, transitional cell carcinoma, malignant Brenner's tumor or adenocarcinoma not otherwise specified.

3. Patient must have measurable disease as defined by RECIST 1.1.

4. Patients must have received treatment with a platinum-based chemotherapeutic regimen for management of primary disease containing carboplatin, cisplatin or another organoplatinum compound. This initial treatment may have included intraperitoneal therapy, consolidation, non-cytotoxic agents or extended therapy administered after surgical or non-surgical assessment.

   Patients are allowed to receive, but are not required to receive, one additional cytotoxic regimen for management of recurrent or persistent disease.

   Patients are allowed to have received, but are not required to have received, biologic/targeted therapy (e.g., bevacizumab and/or PARP inhibitor) as part of their primary treatment regimen or for management of recurrent or persistent disease.

5. Patients must have platinum-resistant disease, defined as having a platinum-free interval (PFI) of < 12 months after first- or second-line platinum-based chemotherapy, or having disease progression while receiving second-line platinum-based chemotherapy.

6. Patients must have adequate bone marrow, renal, hepatic, and neurologic functions as defined by the following:

   • Bone marrow function: absolute neutrophil count (ANC) ≥ 1,500/mm3. This ANC cannot have been induced or supported by granulocyte colony stimulating factors. Platelets ≥ 100,000/mm3. Hemoglobin ≥ 9 g/dL.
   • Renal function: creatinine ≤ 1.5 x institutional upper limit normal (ULN).
   • Hepatic function: bilirubin < 1.2 mg/dL, SGOT (AST) and SGPT (ALT) ≤ 3.0 x ULN and alkaline phosphatase ≤ 2.5 x ULN.

7. Patients must have recovered from effects of recent surgery, radiotherapy or chemotherapy:

   • Patients should be free of active infection requiring parenteral antibiotics.
   • Any hormonal therapy directed at the malignant tumor must be discontinued at least one week prior to registration. Continuation of hormone replacement therapy is permitted.
   • Any other prior therapy directed at the malignant tumor, including chemotherapy, biologic/targeted agents and immunologic agents, must be discontinued at least three weeks prior to registration.
   • Any prior radiation therapy must be completed at least four weeks prior to registration.

8. Patients must have a GOG performance status of 0 or 1.

9. Patients of childbearing potential must have a negative pregnancy test prior to the study entry and be practicing an effective form of contraception. If applicable, patients must discontinue breastfeeding prior to study entry.

10. Patients must meet the entry requirements and undergo the baseline procedures.

11. Patients must have signed an IRB-approved informed consent form and authorization permitting release of personal health information.

Exclusion Criteria:

1. Patients who have had treatment with VTX-2337, doxorubicin, PLD, or any other anthracycline.
2. Patients who have received an investigational agent < 30 days prior to registration.
3. Patients who have received oral or parenteral corticosteroids < 2 weeks prior to registration or who require ongoing systemic immunosuppressive therapy for any reason.
4. Patients with active autoimmune disease. "Active" refers to any condition currently requiring therapy. Examples of autoimmune disease include systemic lupus erythematosus, multiple sclerosis, inflammatory bowel disease and rheumatoid arthritis.
5. Patients with a history of other invasive malignancies, with the exception of non-melanoma skin cancer, are excluded if there is any evidence of the other malignancy being present within the last three years.
6. Patients who have received prior radiotherapy OTHER THAN for the treatment of ovarian, fallopian tube or primary peritoneal cancer within the last three years are excluded.
7. Patients who have received prior chemotherapy OTHER THAN for the treatment of ovarian, fallopian tube or primary peritoneal cancer within the last three years are excluded.
8. Patients with history or evidence upon physical examination of CNS disease, including primary brain tumor, seizures not controlled with standard medical therapy, any brain metastases, or history of cerebrovascular accident (CVA, stroke), transient ischemic attack (TIA) or subarachnoid hemorrhage within six months of the first date of treatment on this study.
9. Patients with clinically significant cardiovascular disease.
10. Patients who are pregnant or nursing.
11. Patients under the age of 18.
12. Patients with clinical symptoms or signs of gastrointestinal obstruction and/or who require parenteral hydration or nutrition.