The present invention relates to Proton Pump Inhibitors (PPI) for use as immunomodulators which allow to overcome immune escape in antineoplastic therapy chronic inflammatory diseases associated with an acidic microenvironment and in chronic infection thereto associated. The therapeutic efficacy of PPIs is guaranteed by their ability of inhibiting the activity of the hydrogen/potassium adenosine triphosphatase enzyme system (H + /K + - ATPase or proton pump). The PPI according to the present i...

PROBLEM TO BE SOLVED: To provide compositions for reducing gastic acid secretion in a mammal that are capable of enhancing anti-acid activity of gastic H+/K+-ATPase proton pump inhibitor (PPI) in the stomach. SOLUTION: The compositions comprise an irreversible PPI (for example pantoprazole) as a gastic acid secretion inhibitor and one or more small carboxylic acid molecules such as saturated or unsaturated monocarboxylic acid dicarboxylic or tricarboxylic acid molecules having between three to ...