Recent advances in immunotherapy for pancreatic cancer

Pancreatic ductal adenocarcinoma (PDAC) remains a disease with a dismal prognosis. Since 1996 there have only been two upfront regimens found to be superior to gemcitabine: FOLFIRINOX (5-fluorouracil, leucovorin, irinotecan and oxaliplatin), and gemcitabine plus nab-paclitaxel. Despite the improvement noted in these trials, PDAC is highly chemo-resistant and patients who respond will inevitably develop resistance. The unique immunosuppressive tumor microenvironment with extensive desmoplasia has posed challenges to developing new and effective treatments. Therapeutic vaccines, combination treatments, adoptive T cell transfer, as well as immunomodulators are being explored. With the emerging use of immunotherapy and immunomodulators, the scope of this review is to present the current data on these agents as well as focus on the advancements in the treatment of PDAC. Overall, results in this realm have been disappointing to date reflecting the non-immunogenic and complex tumor microenvironment of PDAC.