Influenza virus vector for virotherapy
The present invention provides a recombinant influenza virus vector comprising an NS gene encoding a truncated NS1 protein of at least 73 and up to 122 amino acids of the N-terminus of the respective wild type NS 1 protein, wherein said vector replicates in IFN-sensitive tumor cells and does not replicate in normal, non-tumor cells, and expresses a heterologous immunostimulatory polypetide. The invention further provides a pharmaceutical composition containing said influenza virus vector, its use for the treatment of cancer patients and methods for producing said influenza virus vaccine.
1. A recombinant influenza A virus vector comprising an NS gene encoding a truncated NS1 protein consisting of 106 amino acids of the N-terminus of the respective wild type NS1 protein, wherein said vector:
(i) replicates in IFN-sensitive tumor cells and in IFN-resistant tumor cells, and is attenuated in normal cells, and
(ii) expresses a heterologous immunostimulatory polypeptide, wherein the heterologous polypeptide is a cytokine.
2. The recombinant influenza A virus vector of claim 1 , wherein said influenza virus vector has an IFN-inducing phenotype.
3. The recombinant influenza A virus vector of claim 1 , wherein the IFN-sensitive tumor cells are melanoma cells.
4. The recombinant influenza A virus vector of claim 1 , wherein the NS gene is further modified by mutations in the noncoding region.
5. The recombinant influenza A virus vector of claim 1 , wherein the vector comprises modifications of the genes encoding the NA and/or HA proteins.
6. The recombinant influenza A virus vector of claim 1 , wherein the vector comprises modifications of the polymerase genes encoding the PB1, PB2, PA, and/or NP proteins.
7. A composition comprising the recombinant influenza A virus vector of claim 1 and a physiologically acceptable excipient.
8. A method of inducing an immune response in a subject, comprising the step of administering an effective amount of the recombinant influenza A virus vector of claim 1 to a subject in need thereof.
9. The composition of claim 7 , further comprising an immunomodulatory molecule.
10. The composition of claim 9 , wherein the immunomodulatory molecule is an antibody.
11. The composition of claim 9 , wherein the immunomodulatory molecule is an antagonist of CTLA-4, PD-1or 4-1BB21.
12. The method of claim 8 , wherein the recombinant influenza A virus vector is administered to the subject on a plurality of occasions.
13. The recombinant influenza A virus vector of claim 1 , wherein the wild type NS1 protein has the sequence of SEQ ID NO:1.
14. The recombinant influenza A virus vector of claim 1 , wherein the vector is derived from an influenza virus subtype H1N1.
15. A recombinant influenza A virus vector comprising an NS gene encoding a truncated NS1 protein consisting of 106 amino acids of the N-terminus of the respective wild type NS1 protein, wherein said vector:
(i) replicates in IFN-sensitive tumor cells and in IFN-resistant tumor cells, and is attenuated in normal cells, and
(ii) expresses a heterologous immunostimulatory polypeptide, wherein the heterologous polypeptide is a cytokine selected from the group consisting of IL2, GM-CSF, IL-15,MIP 1alpha, and MIP3 alpha.
16. The recombinant influenza A virus vector of claim 15 , wherein the cytokine is IL2.