Arm A: 30 mg GC4419 per day (60 min IV infusion to complete within 60 minutes prior to IMRT), concurrent with daily fractions of IMRT (2.0 - 2.2 Gy) to a total of 60 - 72 Gy over approximately 7 weeks, plus cisplatin administered 80 - 100 mg/m2 once every three weeks for 3 doses or 30 - 40 mg/m2 once weekly for 6-7 doses (investigator's choice).