Inclusion Criteria:

• written informed consent
• At least 18 years old.
• Histologically confirmed, FIGO stage II-IV epithelial ovarian, fallopian tube or primary peritoneal carcinoma that was treated with surgical debulking and at least five cycles of platinum-taxane doublet chemotherapy.
• Study randomization at least 3 weeks and not more than 12 weeks from the date of the last chemotherapy dose, and all major toxicities from the previous chemotherapy must have resolved.
• No evidence of disease progression
• ECOG status of 0 or 1.
• Able to swallow and retain oral medication.
• Adequate hematologic, hepatic, and renal system function as follows:

Hematologic

• Absolute neutrophil count (ANC) at least 1.5 X 10^9/L
• Hemoglobin at least 9 g/dL (or 5.59 mmol/L)
• Platelets at least 100 X 10^9/L
• Prothrombin time (PT) or international normalized ratio (INR) up to 1.2 X ULN
• Activated partial thromboplastin time (aPTT) up to 1.2 X ULN Hepatic
• Total bilirubin up to 1.5 X ULN
• AST and ALT up to 2.5 X ULN Renal
• Serum creatinine up to 1.5 mg/dL

Or, if greater than 1.5 mg/dL:

Calculated creatinine clearance at least 50 mL/min Urine Protein

• Urine protein is 0, trace, or +1 determined by dipstick urinalysis, or < 1.0 gram determined by 24- hour urine protein analysis.
• Non-childbearing potential (i.e., physiologically incapable of becoming pregnant) OR childbearing potential, and agrees to use adequate contraception.

Exclusion Criteria:

• Either (a) bulky disease, or (b) any residual disease which in the opinion of the investigator will need imminent second-line therapy
• Synchronous primary endometrial carcinoma, or a past history of primary endometrial carcinoma, are excluded unless certain conditions are met.
• Clinically significant gastrointestinal abnormalities
• Prolongation of corrected QT interval (QTc) > 480 msecs
• History of any one or more cardiovascular conditions within the past 6 months prior to randomization
• Poorly controlled hypertension
• History of cerebrovascular accident (including transient ischemic attacks), pulmonary embolism or untreated deep venous thrombosis (DVT) within the past 6 months prior to randomization
• Major surgery (including interval debulking) or trauma within 28 days, or minor surgical procedures within 7 days, prior to randomization, or has any non-healing wound, fracture, or ulcer.
• Evidence of active bleeding or bleeding diathesis.
• Hemoptysis within 6 weeks prior to randomization.
• Endobronchial metastases.
• Serious and/or unstable pre-existing medical (e.g., uncontrolled infection), psychiatric, or other condition that could interfere with subject's safety, provision of informed consent, or compliance to study procedures.
• Investigational or anti-VEGF anticancer therapy prior to study randomization.
• Known immediate or delayed hypersensitivity reaction or idiosyncrasy to drugs chemically related to pazopanib.