Primary Outcome Measures:
- Reduction in tumor blood flow and permeability of vessels
Secondary Outcome Measures:
- Response rate (time to progression, rate of objective response, and rate and duration of disease control)
- Safety (adverse events [AEs], lab tests and physical examinations)
- Reduction in circulating endothelial cells (CECs)
- Reduction in circulating endothelial progenitor cells (CEPs)
Angiogenesis, defined as the growth of new blood vessels from pre-existing vessels, is a requirement for the growth of nearly all tumors. Clear cell renal cell carcinoma (CCRCC) is a malignancy characterized by abundant vascularization and a high degree of resistance to chemotherapy which makes antiangiogenic therapy an intriguing concept for treatment. This concept has been established by the initial successes observed in recent studies of antiangiogenic therapies for CCRCC. ATN-161 is an attractive candidate for investigation as a therapeutic agent in CCRCC because it binds to several fully activated integrins, which are essential downstream components in the angiogenic signaling cascade.
Functional imaging using dceMRI has been demonstrated as an effective way to show effects on the vasculature across different tumors, including CCRCC. Preclinical experiments have shown that ATN-161 affects tumor perfusion in tumor bearing mice. Therefore, use of imaging in this study is expected to be an effective method for evaluating the antiangiogenic response to ATN-161.
Patients will be administered ATN-161 three times weekly by short (10 minute) IV infusion at 1 of 3 dose levels (20, 100, and 600 mg). Patients will be treated until progression of disease, unacceptable drug toxicity, or withdrawal of consent occurs.
Functional imaging (dceMRI) will be performed within 1 week prior to first treatment, again during the second week of treatment, and finally during the fourth week of treatment.