This is a multicenter, double-blind, placebo-controlled, randomized study of fosbretabulin given with chemotherapy (paclitaxel and carboplatin) compared to placebo given with chemotherapy (paclitaxel and carboplatin) in subjects with anaplastic thyroid cancer (ATC). The primary objective of the study is to determine overall survival. A maximum of 300 subjects will be recruited from approximately 75 multinational sites of which approximately 35 will be located in the United States.