A preparation of autologous T-lymphocytes that are genetically modified with a viral vector encoding a T-cell receptor (TCR) targeting an as of yet undisclosed patient-specific tumor associated antigen (TAA), with potential antineoplastic activity. Upon intravenous administration back into the patient, the autologous TCR-engineered T-cells IMA203 specifically recognize and bind to the TAA on cancer cells, which induces a cytotoxic T-lymphocyte (CTL)-mediated immune response against the TAA-positive cancer cells.