This clinical trial is for adult participants who have metastatic pancreatic cancer and have been given prior chemotherapy with FOLFIRINOX (5FU + leucovorin + irinotecan + oxaliplatin).

The purpose of this study is to determine the safety and effectiveness of a new study drug called botensilimab (AGEN1811) when given in combination with the drugs nab-paclitaxel + gemcitabine in patients with metastatic pancreatic cancer. Botensilimab is an experimental drug that has not yet been approved for general use by the U.S. Food and Drug Administration (FDA).
   
The study drug Botensilimab (AGEN1811) is an immune-based therapy that may be effective against pancreatic cancer. In this study, it will be evaluated when given in combination with the standard of care nab-paclitaxel + gemcitabine in people who have had progression of their pancreatic cancer following prior chemotherapy with FOLFIRINOX, with the goal of improving response to nab-paclitaxel + gemcitabine.

Nab-paclitaxel and gemcitabine are both approved by the FDA.
   
Not all participants will receive botensilimab. Some will only receive the standard of care regimen of Nab-paclitaxel + gemcitabine. The study doctor will inform participants which part of the study they are being asked to participate in.
   
Participants who receive the study drug botensilimab will receive up to 3 doses in total over a 16-week period. Treatment will be given as an intravenous (IV) infusion. This means that the study treatment will go straight into the vein through an IV line.

The participant will then continue on nab-paclitaxel + gemcitabine until intolerable toxicity, disease progression, or they wish to discontinue from study treatment for any reason. Therefore, the duration of the study will depend on how long participants continue to receive standard of care treatment.