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