Orally active, selective inhibitor of EGFR tyrosine kinase (IC50 = 23 - 79 nM). Shows minimal activity against ErbB2, KDR, c-flt, PKC, MEK and ERK-2. Blocks EGFR autophosphorylation and inhibits tumor growth in mice bearing a range of human xenografts. Also inhibits growth of brain metastases in mouse model of non-small cell lung cancer. View information regarding the usage of Iressa for non-clinical studies . Purity 98%. MW (observed): 446.9