All study drug will be administered on an inpatient basis and the patient will remain confined for 24 hours following study drug administration for evaluation of safety and collection of specified body fluid samples for plasmid IL-12-DNA and cytokine determinations. Each patient will receive the same dose of EGEN-001 once weekly for four weeks (administered on Day 0, Day 7, Day 14, and Day 21). Patients will undergo safety evaluations 1, 4 and 24 hours and 3 days following each dose. Patients will return to the clinic for safety evaluations three days, one week and five weeks (± one week) following the last dose.