This is a Phase I study to test the safety, pharmacokinetics and effectiveness of STM 434 alone, or in combination with liposomal doxorubicin, in patients with ovarian cancer or other advanced solid tumors.

This is an open-label (identity of assigned study drug will be known) study to evaluate the safety, pharmacokinetics (study of what the body does to a drug), pharmacodynamics (study of what a drug does to the body), and anti-tumor activities of STM 434 (an inhibitor of activin A) in patients with ovarian cancer and other advanced solid tumors. The study will be conducted in 3 phases (Part 1, Part 2 and Part 3). In the first part of the study (Part 1), which will enroll patients with multiple solid tumor types, the maximum tolerated dose (MTD) of STM 434 will be determined for use in the second and third parts of the study (Parts 2 and 3). In the second part (Part 2), which will enroll patients with ovarian cancer, STM 434 will be administered alone, and in the third part (Part 3), which will enroll patients with ovarian cancer, STM 434 will be given together with a chemotherapy called liposomal doxorubicin. Doses of STM 434 (starting at 0.25 mg/kg up to a maximum of 4 mg/kg) will be taken on one of three dosing schedules to determine the MTD. Patients will continue taking STM 434 until their tumor progresses. Serial blood samples will be collected for pharmacokinetic and pharmacodynamic testing and safety will be monitored throughout the study.

Inclusion Criteria:

• Males and postmenopausal females, 18 years or older
• Advanced solid tumors with histologic diagnosis confirming cancer
• Patients with recurrent metastatic or locally advanced disease considered refractory or intolerant to all standard treatment available for their tumor, or those tumors for which no standard treatment is available
• Subjects with serous ovarian/fallopian tube/primary peritoneal, granulosa cell tumors or clear cell tumors considered platinum refractory/resistant, defined as having at least one prior platinum-based chemotherapeutic regimen with a subsequent platinum-free interval of < 12 months, having progression during platinum-based therapy, or having persistent disease after a platinum-based therapy, are eligible. Intolerant subjects, defined as unable to receive further platinum due to toxicity, are eligible.
• Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1
• Informed consent

Exclusion Criteria:

• History of gastrointestinal bleeding within the past 6 months
• History of epistaxis requiring medical/surgical intervention (such as nasal packing) within the past 6 months
• History of central nervous system hemorrhage
• History of bleeding diathesis or known qualitative platelet defect (including von Willebrand disease)
• Ongoing need for therapeutic anticoagulants (full dose heparin, warfarin, factor Xa or direct thrombin inhibitors; rivaroxaban, apixaban, dabigatran) chronic use of aspirin or anti-platelet agents (ticlopidine or clopidogrel)
• History of hereditary hemorrhagic telangiectasia (HHT, Osler-Weber-Rendu syndrome)
• Myocardial infarction, unstable angina within the past 6 months, or congestive heart failure New York Heart Association Class II or greater
• Chemotherapy, hormonal therapy or radiation therapy within the past 3 weeks, antibody/biologic therapy within 5 half-lives or within the past 4 weeks (whichever is longer)
• Current bowel obstruction
• Brain metastasis
• Known HIV infection and/or active Hepatitis B or C infection
• Prior treatment with any investigational product within the past 4 weeks
• Not willing to use contraception (inclusive of abstinence)