OTL38 for Intra-operative Imaging of Folate Receptor Positive Ovarian Cancer

Inclusion Criteria: * Female patients 18 years of age and older * Have a primary diagnosis, or at high clinical suspicion, of primary ovarian cancer (of epithelial type), planned for primary surgical cytoreduction, interval debulking, or have recurrent ovarian cancer surgery, and: * Who are scheduled to undergo laparotomy for the debulking surgery OR * Who are scheduled to undergo laparoscopy and pre-authorized to undergo laparotomy for the debulking surgery if cancer is detected on the laparoscopy * A negative serum pregnancy test at Screening followed by a negative urine pregnancy test on the day of surgery or day of admission for female patients of childbearing potential * Female patients of childbearing potential or less than 2 years postmenopausal agree to use an acceptable form of contraception from the time of signing informed consent until 30 days after study completion * Ability to understand the requirements of the study, provide written informed consent for participation in the study and authorization of use and disclosure of protected health information, and agree to abide by the study restrictions and to return for the required assessments Exclusion Criteria: * Previous exposure to OTL38 * Known FR-negative ovarian cancer * Planned surgical debulking via laparoscopy or robotic surgery, with no intent of laparotomy. * Patients with known ovarian cancer miliary disease determined preoperatively to be inoperable. * Any medical condition that, in the opinion of the investigators, could potentially jeopardize the safety of the patient * History of anaphylactic reactions * History of allergy to any of the components of OTL38, including folic acid * Pregnancy or positive pregnancy test * Clinically significant abnormalities on electrocardiogram (ECG) * Presence of any psychological, familial, sociological or geographical condition potentially hampering compliance with the study protocol and follow-up schedule * Impaired renal function defined as eGFR\< 50 mL/min/1.73m2 * Impaired liver function defined as values \> 3x the upper limit of normal (ULN) for alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), or total bilirubin. * Known Stage IV ovarian cancer with brain metastases * Received an investigational agent in another clinical trial within 30 days prior to surgery * Known sensitivity to fluorescent light