Focal adhesion kinase (FAK) and proline-rich tyrosine kinase 2 (PYK2) are non-receptor tyrosine kinases that constitute the FAK subfamily and play a vital role in many oncogenic pathways.{15630} PF-562271 is an ATP-competitive, reversible inhibitor of FAK (IC50 = 1.5 nM) that demonstrates 10-fold reduced potency for PYK2 (IC50 = 14 nM) and >100-fold selectivity against other protein kinases.{29911} PF-562271 inhibits FAK phosphorylation with an EC50 value of 93 ng/ml in glioblastoma-bearing mice and has been shown to regress tumors in multiple xenograft models.{29911,29912}