Definition

An orally bioavailable cholecystokinin (CCK) receptor antagonist, with gastric acid reducing and potential antineoplastic activities. Upon oral administration, proglumide binds to and blocks both cholecystokinin receptor type A (CCK-AR; CCK1-R) and gastrin/cholecystokinin type B receptor (CCK-BR; CCK2-R). This prevents the binding of cholecystokinin and gastrin to the CCK receptors, and inhibits both gastrointestinal (GI) motility and gastric secretions. This may also decrease fibrosis in the tumor microenvironment (TME), increase both the infiltration of T-cells and the penetration of chemotherapeutic agents, and inhibit tumor growth and metastasis. CCK receptors, normally expressed in the GI tract and the nervous system, are overexpressed on fibroblasts and certain cancers.