* corresponding author: kristian@syntbio.net

Malignant tumors are a major cause of death and for several tumor types new specific and effective therapies are urgently needed. The epidermal growth factor receptor (EGFR) is a validated tumor marker for several therapeutic antibodies but is also abundantly expressed on healthy tissue. Recombinant adeno-associated viruses (rAAV) are preferred for gene therapy due to their low immunogenicity, long-term stable transgene expression and low cytotoxicity. We explore the use of rAAV for tumor therapy by re-targeting of the capsid and endowing them with a gene coding for a prodrug activating enzyme. Here, we inserted at the genetic level the EGFR binding Affibody ZEGFR:1907 in the 453-loop area of rAAV2-VP2 resulting in a mosaic rAAV named rAAV2-VP2-453Affi. This rAAV2 variant bound to EGFR overexpressing cells (A431) but not to EGFR depleted cells (MCF7). Transduction efficiency correlated well with reported cell-surface EGFR levels on model cell lines. We further observed transduction of neuroendocrine tumor (NET) cell lines (BON, QGP) and patient derived NET organoids and their successful in-vitro tumor cell killing. Using thymidine kinase as suicide gene in a virus-directed enzyme product therapy (VDEPT) with ganciclovir (GCV) treatment drastically reduced cell metabolism and viability. Based on our results, re-targeting of rAAVs enables antibody-like tumor marker specificity. In the future, the combination of receptor-specific cellular targeting with translational and transcriptional targeting afforded by rAAVs will provide specificity superior to that of antibodies and will expand the choice of personalized therapies.