Photodynamic priming synergizes with anti-PD1 therapy to improve survival in a preclinical pancreatic tumor model

Pancreatic ductal adenocarcinoma (PDAC) is characterized by extensive desmoplasia which is considered to be a primary cause of treatment resistance observed in these tumors. Desmoplasia also plays a major role in mediating an immunosuppressive microenvironment and restricting immune cell infiltration in PDAC. In this study, using a syngeneic orthotopic immunocompetent KPC PDAC model, we demonstrate that PDT using Visudyne® can alter the tumor microenvironment, enhances immune cell infiltration, significantly reducing tumor growth and increasing survival in combination with anti-PD1.