In vitro activity: AL082D06 (formerly known as D-06), is a nonsteroidal glucocorticoid receptor (GR) antagonist which is characterized by a tri-aryl methane core chemical structure. AL082D06 binds with nanomolar affinity to the GR and has no detectable binding affinity for the highly related receptors for mineralocorticoids, androgens, estrogens, and progestins. AL082D06 inhibits glucocorticoid-mediated transcriptional regulation. AL082D06 binds competitively with steroids, likely occupying a similar site within the ligand-binding domain. Once bound, however, AL082D06 fails to induce critical conformational changes in the receptor necessary for agonist activity.

Kinase Assay: AL 082D06 is a selective, nonsteroidal glucocorticoid receptor (GR) antagonist with Ki of 210 nM. AL082D06 acts to antagonize reporter activity using several glucocorticoid-responsive promoter- reporter systems including the 3-kb tyrosine amino transferase (TAT) promoter and less complex promoters comprised of isolated glucocorticoid response element (GRE) sequences. AL 082D06 competes with 3H-Dex for baculovirus-expressed GR with nanomolar affinity. Other intracellular receptors (AR, ER, PR, and MR) have no affinity for AL 082D06 in a similarly structured binding assay with the appropriate receptor and tritiated ligand (>2500 nM). AL 082D06 has no activation efficacy on the progesterone, androgen, mineralocorticoid, retinoid, glucocorticoid, or estrogen receptors. AL 082D06 is very efficacious at antagonizing GR activity but exhibits much weaker efficacy when tested against the other steroid receptors in contrast to the reference antagonists used as controls.

Cell Assay: