A combination of immunotherapy and chemotherapy has also been used by a nano-enabled approach against highly refractive pancreatic ductal adenocarcinoma (PDAC) using synergistic dual drug delivery.168 Oxaliplatin was used to induce immunogenic cell death (ICD) whereas another drug indoximod was used to block a regionally overexpressed immunosuppressive enzyme, indoleamine 2,3-dioxygenase 1 (IDO1) (which interfere with cytotoxic T cells (Tc) development and induce immunosuppressive T regulatory cells (Treg)). This evidence concerns the gene IDO1 and pancreatic ductal adenocarcinoma.