Batiraxcept (AVB-S6-500)/Placebo in Combination With Paclitaxel in Patients With Platinum-Resistant Recurrent Ovarian Cancer

Inclusion Criteria: * Histologically confirmed and documented recurrent ovarian, fallopian tube, or peritoneal cancer. Only patients with high-grade serous adenocarcinoma histology are eligible. * Aged 18 years or older * Eastern Cooperative Oncology Group performance status (ECOG-PS) of 0 to 1 * Platinum-resistant disease (defined as progression within ≤6 months from completion of most recent platinum-containing regimen and calculated from the date of the last administered dose of platinum therapy).Subject may have been treated with additional regimen(s) subsequent to determination of platinum resistance. * Available archived tumor tissue or if archived tissue is not available, a fresh tumor biopsy. * Received at least 1 but not more than 4 prior therapy regimens. Note: Maintenance therapy OR hormonal therapies should not be counted as a separate therapy. Note: Patients who have not received prior bevacizumab must be deemed medically inappropriate OR ineligible to receive bevacizumab, refused to receive bevacizumab, or been unable to receive bevacizumab due to lack of access. * Measurable disease according to RECIST v1.1 criteria * Normal gastrointestinal function. * At least 28 days between termination of prior anticancer or hormonal therapy and first administration of batiraxcept. * Full recovery from all treatment-related toxicities to Grade 1 or less, except alopecia. Exclusion Criteria: * Tumors in the breast or bone * Untreated central nervous system (CNS) metastases. Subjects requiring corticosteroid therapy for the management of their treated CNS metastases may not be on \>10 mg/day prednisone or equivalent or have demonstrated signs or symptoms of neurologic instability for 28 days or less prior to randomization. * Primary platinum-refractory disease (defined as progression during or within 4 weeks after completion of the first platinum regimen) * Is being treated with concurrent anticancer therapy or other interventional treatments administered for their underlying ovarian cancer. * Received prior therapy with PAC in the platinum-resistant recurrent setting * Evidence of clinically significant third spacing (e.g., pleural effusions, ascites, anasarca, etc.) that requires therapeutic intervention within 28 days prior to first dose of batiraxcept/placebo