It is a tyrosine kinase inhibitor.

Competitor assay kits (green) are used to determine relative in vitro binding affinities of ARN-509 for the rat AR ligand binding domain (LBD), human progesterone receptor (PR) LBD, and full-length human estrogen receptor-alpha (ERα) and human glucocorticoid receptor (GR). Each hormone dose is performed in triplicate, relative error is calculated from the standard error of the mean (SEM), and binding curves are fit using a single binding site competition model (Prism statistical analysis software package) with R2>0.8. Experiments are conducted multiple times with SEM<0.3 log units from the average logIC50 value. Ki values are calculated as averages across experiments with SEM, and binding affinities are reported as a percentage relative to the tight-binding ligand control for that receptor[1].