Leveraging Gene Therapy to Achieve Long-Term Continuous or Controllable Expression of Biotherapeutics

T cells redirected to cancer cells either via a chimeric antigen receptor or a bispecific molecule have been breakthrough technologies in cancer immunotherapy, yet each have significant limitations. Here we present an off-the-shelf, single dose solution for achieving prolonged systemic exposure (>1 year) of constitutively secreted protein-based immunotherapeutics via adeno-associated virus gene transfer. We demonstrate proof of principle using a single intravenous dose of AAV expressing a secreted version of blinatumomab to treat a CD19+ lymphoma model. In addition, we created an inducible version by reverse engineering a defective exon into its coding sequence that was excluded following the intravenous administration of a morpholino, restoring expression of the immunotherapeutic. We achieved repeated, intermittent in vivo transgene expression lasting 2-3 weeks following systemic morpholino administration up to 36 weeks after AAV injection. Our system could be considered for transient and/or repeated expression of other transgenes of interest for non-cancer applications.