Abstract: A mutant virus for use as a vaccine for prophylaxis or therapy, wherein the genome of the virus is defective in respect of a gene essential for the production of infectious virus. In one aspect the mutant virus, e.g. a herpesvirus, e.g HSV-1 or HSV-2, is capable of protecting a susceptible species immunised therewith against infection by the corresponding wild-type virus. In another aspect, the mutant virus acts as a vector for an immunogenic protein derived from a pathogen, encoded by foreign DNA incorporated in the mutant virus. The mutant virus can be produced by a recombinant host cell which expresses a gene complementing the defect. The mutant virus can be infectious for the host to be protected, and the genetic defect can allow expression in the infected host of at least some of the viral genes, which can provoke a cell-mediated immune response. The defect can be in a glycoprotein gene such as gH.

Abstract: A mutant virus for use as a vaccine, wherein the genome of the virus is defective in respect of a gene essential for the production of infectious virus. In one aspect the mutant virus is capable of protecting a susceptible species immunized therewith against infection by the corresponding wild-type virus. In another aspect, the mutant virus acts as a vector for an immunogenic protein derived from a pathogen and which is encoded by foreign DNA incorporated in the mutant virus. The mutant virus can be produced in a recombinant host cell which expresses a gene complementing the defect. The mutant virus is preferably infectious for the host to be protected, but the defective gene allows expression in the infected host of at least some of the viral genes, which can provoke a cell-mediated immune response.

Abstract: The application provides a pharmaceutical which comprises a mutant non-retroviral virus (particularly HSV-1 and/or HSV-2) whose genome is defective in respect of a gene essential for the production of infectious virus. The virus can infect normal cells and undergo replication and expression of viral antigen genes in those cells but cannot produce normal infectious virus. The pharmaceutical is for prophylactic or therapeutic use in generating an immune response in a subject infected therewith. Where the non-retroviral virus is a herpes simplex virus eg HSV-1 or HSV-2, the defect can be in the glycoprotein gH gene. Vaccines and therapeutic pharmaceuticals are provided especially for epithelial, oral, vaginal and nasal administration. Also provided is use of a mutant based on HSV-1 for the preparation of a pharmaceutical for prophylactic or therapeutic use in generating an immune response in a subject against type-2 HSV infection.

Abstract: A mutant virus for use as a vaccine, wherein the genome of the virus is defective in respect of a gene essential for the production of infectious virus. In one aspect the mutant virus is capable of protecting a susceptible species immunized therewith against infection by the corresponding wild-type virus. In another aspect, the mutant virus acts as a vector for an immunogenic protein derived from a pathogen and which is encoded by foreign DNA incorporated in the mutant virus. The mutant virus can be produced in a recombinant host cell which expresses a gene complementing the defect. The mutant virus is preferably infectious for the host to be protected, but the defective gene allows expression in the infected host of at least some of the vital genes, which can provoke a cell-mediated immune response.