Medarex, Inc. and Bristol-Myers Squibb Company announced today that complete or partial responses in seven of 56 patients with metastatic melanoma showed durability ranging from four months to the longest still ongoing at over 34 months, with five of the seven responses ongoing for more than two years.
These patients were treated in a Phase II clinical study with the investigational fully human anti-CTLA-4 antibody, MDX-010, in combination with MDX-1379, a gp100 melanoma vaccine. The Phase II clinical trial was conducted by Steven A. Rosenberg, M.D., Ph.D., Chief of Surgery at the National Cancer Institute, under a Cooperative Research and Development Agreement with Medarex. Results from the clinical trial were presented at the 96th Annual Meeting of the American Association of Cancer Research, April 16- 20, 2005, in Anaheim, CA.
The Phase II clinical trial evaluated two dose regimens of MDX-010 in combination with MDX-1379 in a total of 56 patients with metastatic melanoma. All patients had stage IV disease, Karnofsky performance status greater than or equal to 60, no previous MDX-010 treatment or gp100 vaccination, no evidence of autoimmune or immunodeficiency, and 3 weeks had elapsed since any previous systemic cancer therapy. Of the 56 patients, 29 patients (cohort 1) received 3.0 mg/kg intravenously over 90 minutes of MDX-010 and MDX-1379 every three weeks, and 27 patients (cohort 2) received an initial dose of 3.0 mg/kg intravenously over 90 minutes of MDX-010 and MDX-1379, followed by subsequent doses of 1.0 mg/kg of MDX-010 every three weeks. Data on the initial 14 patients in cohort 1 and the initial 24 patients in cohort 2 were previously presented at the 2003 annual meeting of the American Society of Clinical Oncology.
Four of the 29 patients treated in cohort 1 experienced complete or partial responses. Two patients experienced complete responses that are ongoing at over 30 and 31 months, respectively, and two additional patients experienced partial responses, with one response lasting four months and the other ongoing at over 34 months. In cohort 2, three of 27 patients experienced partial responses, with one partial response ongoing to six months and two partial responses ongoing at 25 and 26 months, respectively.