All pan-BET inhibitor clinical trials have been Phase 1 or 2 oncology trials. The only selective (non-pan) BET inhibitor in clinical trials that I know of are  apabetalone and ABBV-744. But ABBV-744 is only in early oncology trials. So by default, apabetalone is a) the only selective BET inhibitor in non-oncology clinical trials b) the only BET inhibitor in a cardiovascular outcomes trial; and c) the only BET inhibitor in a Phase 3 trial. I don't know of any other epigenetic (non BET inhibitors) drugs being investigated for cardiovascular indications.