Patients receive vaccine (or vaccine placebo) injections at Weeks 0, 8, 16, 24, and 48. IL-2 injections are synchronized with vaccine injections. IL-2 is given open-label while vCP1452 is double-blinded. Patients must be on Step I for a minimum of 51 weeks [AS PER AMENDMENT 08/23/01: prior to entry into Step II].