Axelopran (INN, USAN) (developmental code name TD-1211) is a drug which is under development by Theravance Biopharma and licensed to Glycyx for all indications.

An extensive body of literature has shown diverse and profound immunosuppressive effects of μ-opioid activation in vivo and in vitro.

[6] Recent data for axelopran in three different pre-clinical models of cancer shows that a μ-opioid antagonist isolates distinct effects of the endogenous opioid system on tumor growth and works in combination with checkpoint inhibitors.

Furthermore, axelopran and murine anti-PD-1 antibody were synergistic in slowing tumor growth and increasing survival in the syngeneic mouse model.

Axelopran has potent μ-opioid receptor antagonist activity on the gastrointestinal tract in vivo, and thus it produces a dose-dependent inhibition of opioid-induced delaying in gastric emptying in mice and rats following subcutaneous or oral administration.