An interesting read. Seems that there is more and more interest in bromodomain (BD) selective BET inhibitors. I posted last month about Abbvie's ABV-744 compound. This paper linked below (thanks for the heads up Aureus on IV) has a lot of GSK authors, so seems that GSK is a contender in the BD-selective BET inhibitor arena now too. I'm not sure if this paper has open access, so you may not be able to read.

In this paper, they did a focused library screening to identify a series of tetrahydroquinoxalines with high selectivity for BD2 (much more so than apabetalone). However, the important thing to keep in mind is that BD selectivity isn't the only determinant to how a BET inhibitor will alter gene expression. Different compounds may bind slightly differently to the BET protein and alter the structure in a different way, which can have huge implications on how transcription is affected. So although apabetalone has somewhat modest BD-2 selectivity relative to ABBV-744 and some of these GSK compounds detailed in this paper, as of right now none of these other players have shown that their compounds elicit the same array of effects achieved by apabetalone.

Discovery of Tetrahydroquinoxalines as Bromodomain and Extra-Terminal Domain (BET) Inhibitors with Selectivity for the Second Bromodomain.

https://www.ncbi.nlm.nih.gov/pubmed/29656650