AstraZeneca entered into an exclusive licensing deal that could be worth over $1.2 billion for the global rights to develop and market Rigel’s late-stage RA drug, fostamatinib. Fostamatinib is an oral inhibitor of spleen tyrosine kinase (Syk) and in patients with RA who have failed to respond to methotrexate along, fostamatinib has led to significant improvements in symptoms as compared with placebo. The company expects to file for regulatory approval of the drug in 2013.