Inclusion Criteria:

- Histologically or cytologically confirmed diagnosis of soft tissue sarcoma with
measurable disease.

- Target tumors outside prior radiation field(s).

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

- Adequate hematologic profile, as determined by hemoglobin, platelet, and neutrophil
count.

- Adequate renal function

- Adequate liver function

- No history of hemorrhagic cystitis or evidence of microscopic hematuria

- Capable of understanding the protocol requirements and risks and providing written
informed consent.

- Either 0 or 1 prior chemotherapy regimens

Exclusion Criteria:

- Subject has a diagnosis of gastrointestinal stromal tumors.

- Concurrent serious medical illness unrelated to tumor within the past 6 months.

- Known chronic infectious disease, such as AIDS or hepatitis.

- Positive screening pregnancy test or is breast-feeding.

- A female or male subject of reproductive capacity unwilling to use methods
appropriate to prevent pregnancy during the course of this study.

- Receiving concurrent chemotherapy, radiotherapy, or surgery, or has received wide
field radiation within the previous 4 weeks.

- History of another active malignancy (except non-melanoma skin cancer and carcinoma
in situ of the cervix), unless in complete remission and off all therapy for that
disease for the last 2 years.

- Known or clinically suspected brain metastases.

- Received more than one prior treatment regimen (excluding adjuvant or neoadjuvant
therapy) for soft tissue sarcoma.

- Received any investigational drug within the last 30 days.

- Not fully recovered from any prior surgery (at least 4 weeks recovery period for
major surgery), and from any reversible side effects related to the administration of
cytotoxic chemotherapy or radiation therapy.

- Received a prior camptothecin analog (e.g., topotecan, irinotecan).