Packaging systems for human recombinant adenovirus to be used in gene therapy

An adenoviral producer cell that does not produce replication competent adenovirus, said adenoviral producer cell comprising:

• one or more recombinant nucleic acid molecules having no overlapping sequences with respect to one another which would otherwise allow for homologous recombination leading to replication competent adenovirus in said adenoviral producer cell, and wherein said adenoviral producer cell comprises a nucleic acid encoding adenoviral E1A and E1B gene products, said nucleic acid lacking a gene coding for functional or active pIX.

An adenoviral producer cell that does not produce replication competent adenovirus, said adenoviral producer cell comprising:

• one or more recombinant nucleic acid molecules having no overlapping sequences with respect to one another which would otherwise allow for homologous recombination leading to replication competent adenovirus in said adenoviral producer cell, and wherein said adenoviral producer cell comprises a nucleic acid encoding adenoviral E1 and E1B gene products, said nucleic acid lacking a gene coding for functional or active pIX, and E2A gene product under the control of an inducible promoter.

An adenoviral producer cell that does not produce replication competent adenovirus, said adenoviral producer cell comprising:

• one or more recombinant nucleic acid molecules having no overlapping sequences with respect to one another which would otherwise allow for homologous recombination leading to replication competent adenovirus in said adenoviral producer cell, said adenoviral producer cell comprises a nucleic acid encoding adenoviral E1 and E2A gene products, said nucleic acid lacking a gene coding for functional or active pIX, and wherein said E2A gene product encodes a temperature sensitive mutation.

An established adenoviral producer cell that lacks a gene encoding for active or functional pIX and does not produce replication competent adenovirus, said established adenoviral producer cell derived from a primary cell, said established adenoviral producer cell comprising:

• one or more recombinant nucleic acid molecules having no overlapping sequences within each of the recombinant nucleic acid molecules, wherein said adenoviral producer cell comprises DNA sequences encoding functional adenoviral E1A and E1B gene products.