Open Label Phase II Study of AntiCTLA4 in Patients With Unresectable or Metastatic Uveal Melanoma

This is a Phase 2, multi-center, open-label study in patients with surgically incurable stage III or IV uveal melanoma who have not received prior immunotherapy. Patients may have received prior chemotherapy or biological therapy for the treatment of advanced disease. Twenty-nine patients will be enrolled. Patients may have either measurable disease or non-measurable disease.

Patients will receive CP-675,206 at 15 mg/kg administered intravenously on day 1 of every 90-day cycle for up to 4 cycles or until disease progression or intolerance of toxicity. Each cycle is defined as a 90 +/- 4 days period. Patients should be weighed within 10 days prior to each cycle and the administered dose of CP-675,206 should be recalculated.

Patients who complete 4 doses of CP-675,206 without disease progression and who subsequently experience disease progression more than 3 months after the last dose may receive 4 additional doses of CP-675,206 provided that they have not received other systemic therapy for their melanoma. Patients with clinical benefit may be considered for additional dosing if evidence emerges supporting ongoing maintenance therapy.

Tumor assessments will be done every 3 months. All patients with objective tumor response must have additional scans scheduled 4-6 weeks after the criteria for response are first met in order to confirm the response. Additional scans will be done if clinically indicated. Survival will be monitored on all patients for up to 5 years from the date of first dose of CP-675,206. The follow up time may be adjusted based on ongoing studies using CP-675,206 for melanoma.

An exploratory study will be conducted to identify micro environmental features in the tumor that are permissive of tumor immunity (i.e: those associated with a "response" to anti-CTLA4) and to assess whether anti-CTLA4 causes peripheral mobilization of immunomodulatory inflammatory cells.