Immune checkpoint inhibitors, which target PD-1 and CTLA-4, have been shown to be effective in other cancers such as melanoma; however, they have not demonstrated outcome benefits in PDA so far.
Ipilimumab (anti-CTLA-4) has been tested as a single agent in patients with pancreatic ductal adenocarcinoma (PDA) resulting in a delayed response at a dose of 3 mg/kg.