A non-integrating viral delivery system is disclosed. The system includes a viral carrier, wherein the viral carrier contains a defective integrase gene； a heterologous viral episomal origin of replication； a sequence encoding at least one initiator protein specific for the heterologous viral episomal origin of replication, wherein expression of the sequence encoding the at least one initiator protein specific for the heterologous viral episomal origin of DNA replication is inducible； and at least one gene, gene product, shRNA, siRNA, miRNA, or other RNA of interest.
