Inclusion Criteria:

- Male and female subjects aged at least 18 years with histologically-confirmed non
hematological malignancy that is metastatic or unresectable and for which no standard
therapy exists.

- Eastern Cooperative Oncology Group (ECOG) Performance status of 0-2.

- Peripheral neuropathy less than Grade 2 on National Cancer Institute Common Toxicity
Criteria (NCI CTC) version 3 adverse event scale.

- Subjects must have acceptable organ and marrow function during the Screening Period
as defined below. (Note: Subjects must meet these criteria at each pre-dose visit
to receive additional doses of STA-5312).

- Absolute neutrophil count (ANC) greater than 1500 cells/µL

- Platelets greater than 100,000/µL

- Total bilirubin must be <1.5 times ULN

- Aspartate transaminase (AST) ≤3 times ULN or less than 5 times the ULN in
subjects with liver metastases

- Alanine transaminase (ALT) ≤3 times ULN or less than 5 times the ULN in subjects
with liver metastases

- Adequate renal function (serum creatinine <2.0 mg/dL).

- Electrocardiogram (ECG) without evidence of clinically significant ventricular
arrhythmias or active ischemia as determined by the investigator.

- Documented cardiac ejection fraction greater than 50% obtained within 30 days of
administration of the first dose.

- The effects of STA-5312 on the developing human fetus are unknown. Therefore, women
of childbearing potential (defined as women over 50 years of age or history of
amenorrhea for <12 months prior to study entry) must agree to use adequate
contraception (hormonal or barrier method of birth control; abstinence) prior to
study entry and for the duration of study participation. Should a female subject
become pregnant or suspect she is pregnant while participating in this study, she
should inform the treating physician immediately.

- Ability to understand and willingness to sign a written informed consent document.

Exclusion Criteria:

- Women who are pregnant or breast-feeding.

- Subjects who have had chemotherapy or radiotherapy within 4 weeks (6 weeks for
nitrosoureas or mitomycin C) prior to entering the study

- Subjects with previous high-dose chemotherapy with autologous allogeneic
hematopoietic stem cell transplantation.

- Subjects with primary brain tumors or active brain metastases are excluded. Subjects
with previously treated brain metastases who are not receiving corticosteroids or
anticonvulsants are eligible.

- History of stroke within 6 months of treatment or other significant neurological
limitations.

- Use of any investigational agents within 4 weeks of study enrollment.

- History of severe allergic reactions to excipients (e.g. Tween 80/polysorbate 80),
including severe hypersensitivity reactions defined as greater than Grade 3 based on
NCI CTC version 3.

- Uncontrolled intercurrent illness including, but not limited to, human
immunodeficiency virus (HIV)-positive subjects receiving combination antiretroviral
therapy, ongoing or active infection, symptomatic congestive heart failure, unstable
angina pectoris, ventricular arrhythmia, or psychiatric illness/social situations
that would limit compliance with study requirements.