This Phase II study is designed to treat patients who have been diagnosed with Stage IV
Breast Cancer, which has progressed despite treatment with primary therapies, including
hormonal therapy, chemotherapy, and antibody therapy. Thirty-three patients will be treated
with the monoclonal antibody MDX-010. The initial antitumor activity profile of MDX-010 will
be determined, as well as identification of the induction of any antitumor immunity following
the MDX-010 treatment.