R788

R788 is a prodrug of the active compound tamatinib (R-406), which is an inhibitor of the enzyme spleen tyrosine kinase (Syk). R788 (Fostamatinib) effectively inhibits BCR signaling in vivo, resulting in reduced proliferation and survival of the malignant B cells and significantly prolonged survival of the treated animals. R788 also inhibits the anti-IgE-induced production and release of LTC4 and cytokines and chemokines, including TNFα, IL-8 and GM-CSF. R788 (Fostamatinib) induces apoptosis of the majority of examined DLBCL cell lines. Fostamatinib is orally bioavailable and was well tolerated in phase I and II trials, with the most common side effect being gastrointestinal symptoms. Fostamatinib is currently in phase III clinical trials for rheumatoid arthritis and phase II trials for autoimmune thrombocytopenia and lymphoma.