Glutamine antagonists and their use for treating oncological, immunological, and neurological diseases are disclosed. Also disclosed are methods for treating an oncological, immunological, infectious or neurological
disease or disorder, the method comprising administering to a subject in need of treatment thereof a therapeutically effective amount of a
glutamine antagonist of the disclosure or the pharmaceutical composition thereof. Also disclosed are methods of enhancing the effects of an
immune checkpoint inhibitor, enabling a subject to respond to an
immune checkpoint inhibitor, or enabling the
toxicity or the
dose or number of treatments with an
immune checkpoint inhibitor to be reduced, comprising administering to a subject in need of treatment thereof a therapeutically effective amount of a
glutamine antagonist of the disclosure or the pharmaceutical composition thereof, and an immune checkpoint inhibitor. Also disclosed are methods for treating an oncological, immunological, infectious or neurological
disease or disorder that is
refractory to checkpoint inhibitor therapy, the method comprising administering to a subject in need thereof, and having the
refractory disease or disorder, a therapeutically effective amount of a
glutamine antagonist of the disclosure or the pharmaceutical composition thereof.