ISAM-140 is a selective non-xanthinic adenosine A<sub>2B</sub> receptor antagonist. Discovered in 2016, it has a K<sub>i</sub> of 3.49 nM on the A<sub>2B</sub> receptor and >1000-fold selectivity with respect to the other three adenosine receptor subtypes. It has been shown to help the immune system to attack cancer cells in in vitro assays by rescuing T and NK cell proliferation, cytokine release, and TIL infiltration.