ABC-294640 is an orally bioavailable and selective sphingosine kinase-2 (SphK2) inhibitor with IC50 of approximately 60 uM. ABC-294640 inhibits SK2, a lipid kinase that catalyzes formation of the lipid signaling molecule sphingosine 1-phosphate (S1P). S1P promotes cancer growth, and proliferation and pathological inflammation, including TNFα signaling and other inflammatory cytokine production. Specifically, by inhibiting the SK2 enzyme, ABC-294640 blocks the synthesis of S1P which regulates fundamental biological processes such as cell proliferation, migration, immune cell trafficking and angiogenesis, and are also involved in immune-modulation and suppression of innate immune responses from T cells. Preliminary evidence suggests that because of its specificity for targeting SK2, rather than SK1, ABC-294640 may have a better therapeutic ratio than nonspecific sphingosine kinase inhibitors or those targeting only SK1. Oral administration of ABC-294640 to mice bearing mammary adenocarcinoma xenografts results in dose-dependent antitumor activity associated with depletion of S1P levels in the tumors and progressive tumor cell apoptosis. Therefore, this newly developed SK2 inhibitor provides an orally available drug candidate for the treatment of cancer and other diseases. ABC-294640 has completed multiple successful pre-clinical studies in inflammatory, GI, radioprotection and oncology models, as well as a Phase I clinical study in cancer patients with advanced solid tumors.