A Study of STRO-002, an Anti-Folate Receptor Alpha Antibody Drug Conjugate, in Combination With Bevacizumab in Epithelial Ovarian Cancer

Eligibility Criteria

• 1. Age ≥ 18 years.
• 2. ECOG 0-1
• 3. Life expectancy \> 3 months
• 4. High Grade serous epithelial ovarian cancer (EOC), fallopian tube or primary peritoneal cancer with pathology report documentation of tumor type.
• 5. At least one measurable target lesion per RECIST v1.1.
• 6. Tumor tissue for FolRα expression testing prior to enrollment.
• 1. For dose escalation: tissue may be from either archival tumor tissue or from a biopsy performed during screening.
• 2. For dose expansion part of the study, tissue from both archival tumor tissue and a biopsy performed during screening is required.
• 7. Adequate bone marrow function defined as:
• 1. Absolute neutrophil count (ANC) ≥1500/μL
• 2. Hemoglobin ≥ 9g/dL
• 3. Platelet count ≥ 100 x 10\^3/μL
• 8. Adequate liver function defined as:
• 1. ALT and AST \< 2.5 x ULN
• 2. ALP \< 2.5 x ULN
• 3. Bilirubin \< 1.5 x ULN
• 9. Adequate renal function defined as serum creatinine ≤ 1.5 x ULN or creatinine clearance (CrCl) \> 40 mL/min.
• 1. Low grade ovarian carcinoma (Grade 1).
• 2. Clear cell, mucinous, endometrioid, sarcomatous, and mixed histology ovarian carcinomas, endometrial leiomyosarcoma, and endometrial stromal sarcomas.
• 3. Prior treatment with an ADC with a tubulin inhibitor warhead.
• 4. Prior treatment with other FolRα targeting agents unless approved by a Sutro medical monitor or designee.
• 5. Subjects who are primary platinum-refractory during frontline treatment are excluded from the Expansion Cohort (Allowed in Dose Escalation if no more than 1 prior regimen).
• 6. Greater than 4 prior lines of treatment (\> 1 prior if primary platinum refractory).
• 7. Any prior toxicity that required permanent discontinuation of bevacizumab or other contraindication to receive bevacizumab per institutional guidelines.
• 8. Previous solid organ transplantation.
• 9. Current signs/symptoms of bowel obstruction and/or signs/symptoms of or bowel obstruction within 3 months of initiation of study treatment.
• 10. Grade ≥2 toxicity from prior anticancer therapy with the exception of Grade 2 alopecia or Grade 2 neuropathy.
• 11. Uncontrolled hypertension
• 12. Sensory or motor neuropathy Grade \> 1 at screening prior to initiation of study treatment.
• 13. Potentially fatal concurrent or recent malignancy. Subjects with past or current malignancy need to be discussed with the sponsor to determine eligibility.
• 14. Chronic or ongoing active infection requiring systemic treatment.
• 15. Ongoing immunosuppressive therapy, including systemic corticosteroids. Note: Physiologic replacement and use of topical or inhaled corticosteroids are allowed. Dexamethasone may be used to treat chemotherapy induced nausea per institutional guidelines.
• 16. Clinically significant cardiac disease.
• 17. History or clinical signs of meningeal or active central nervous system involvement.
• 18. Known severe COPD or asthma
• 19. Active pneumonitis within 6 months of initiating study treatment.
• 20. History of stroke or history of significant cerebrovascular disease (i.e., transient ischemic attack) within 6 months of initiation of study treatment.
• 21. History of pulmonary embolism or any Grade 3 thromboembolic event within 6 months of initiation of study treatment.
• 22. Known human immunodeficiency virus seropositivity.
• 23. Active hepatitis B or hepatitis C and positive serology (unless due to vaccination or passive immunization due to immunoglobulin therapy) with the following exceptions:
• 1. Subject has had HCV but received antiviral treatment and shows no detectible HCV viral DNA for 6 months prior to screening
• 2. Subject has had HBV but is HBV surface antigen (HBsAg) and viral DNA negative at screening
• 3. Subject has had HBV but received antiviral treatment and have undetectable viral DNA for 6 months prior to screening
• 24. Concurrent participation in another therapeutic treatment trial
• 25. Significant concurrent, uncontrolled medical condition including, but not limited to, renal, hepatic, hematological, gastrointestinal, endocrine, pulmonary, neurological, cerebral or psychiatric disease
• 26. Females who are pregnant or breastfeeding, and all women of childbearing potential unwilling to use adequate barrier contraception while on treatment and for 16 weeks after last dose of STRO-002/bevacizumab and 6 months after the last dose of bevacizumab.