The present invention provides phagemid vectors and associated phagemid particles for cancer treatment, and in particular, to the use of novel phagemid particles and associated expression systems for the treatment, prevention, amelioration, or management of cancer. In particular, the invention relates to the use of phagemid particles and expression systems for the delivery of transgenes encoding cytokines, for the treatment, prevention, amelioration, or management of cancer. The invention also extends to the use of phagemid particles and expression systems for the delivery of transgenes, and for the combination of such treatment with the use of adoptively transferred T cells, for the treatment, prevention, amelioration, or management of cancer.
