This research is to determine which medication, Esmesol (PPI) or Placebo works best at reducing the chance that a patient will get an marginal ulcer after pancreaticoduodenectomy.

Inclusion Criteria:

• Subject is age ≥ 19 years Patient meets the criteria for Open/MIS PPPD Females only: Patient is willing to take a urine pregnancy test

Exclusion Criteria:

- Subject allergic to ESMESOL Patient receiving antifungal (i.e. ketoconazole or itraconazole) Hepatic insufficiency History of Crohns disease History of Zollinger-Ellison disease Patient received an investigational drug within 30 days of enrollment Previous Gastric Surgery HX