In vitro activity: Falnidamol (formerly known as BIBX 1382) is a potent and selective inhibitor EGFR inhibitor with IC50 of 3 nM and potential anticancer activities; it displays> 1000-fold lower potency against ErbB2 (IC50 = 3.4 μM) and a range of other related tyrosine kinases (IC50> 10 μM). BIBX1382 and BIBU1361 are both potent and selective submicromolar inhibitors of the EGFR kinase activity. An IC50 value of 3 nM was determined for both compounds. The potency of these two compounds compares with the one obtained with Iressa, which is a leading EGFR inhibitor in the field. Inhibition of the closest family member, HER2, was 100- to 1000-fold less potent. Furthermore, BIBX1382 and BIBU1361 did not inhibit a number of other related tyrosine kinases.

Kinase Assay: BIBX1382 and BIBU1361 are both potent and selective submicromolar inhibitors of the EGFR kinase activity. An IC50 value of 3 nM was determined for both compounds. The potency of these two compounds compares with the one obtained with Iressa, which is a leading EGFR inhibitor in the field. Inhibition of the closest family member, HER2, was 100- to 1000-fold less potent. Furthermore, BIBX1382 and BIBU1361 did not inhibit a number of other related tyrosine kinases.

Cell Assay: