Background:

pIC50: 7.3

I-BRD9 is a BRD9 inhibitor.

BRD9 is identified as a bromodomain containing protein forming a small sub-branch of the bromodomain family tree. Human BRD9 has a single bromodomain and contains five isoforms which are produced by alternative splicing.

In vitro: In previous study, the I-BRD9 development was driven by iterative medicinal chemistry, using structure based design to result in nanomolar potency at BRD9, over 700-fold selectivity against the BET family as well as more than 70-fold to a panel of 34 bromodomains. In Kasumi-1 cells, I-BRD9 could downregulate DUSP6, CLEC1, SAMSN1 and FES genes. Moreover, I-BRD9 was used to expore genes regulated by BRD9 in Kasumi-1 cells involved in immune response and oncology pathways. In addition, when BRD4 was used as a representative member of the BET family for initial selectivity screening, I-BRD9 was found to have a pIC50 of 5.3 against this protein. I-BRD9 thus represented the first available selective tool compound to investigate the cellular phenotype of the inhibition of BRD9 bromodomain [1].

In vivo: So far, there is no animal in vivo data reported for I-BRD9.

Clinical trial: Up to now, I-BRD9 is still in the preclinical development stage.

Reference:
[1] Theodoulou NH et al.  Discovery of I-BRD9, a Selective Cell Active Chemical Probe for Bromodomain Containing Protein 9 Inhibition. J Med Chem. 2016 Feb 25;59(4):1425-39.