The present embodiments relate to substituted heterocyclic derivative therapeutic compounds, compositions comprising said compounds, and the use of said compounds and compositions for epigenetic regulation by inhibition of bromodomain-mediated recognition of acetyl lysine regions of proteins, such as histones. Said compositions and methods are useful for the treatment of diseases mediated by aberrant cell signalling, such as inflammatory disorders, cancer and neoplastic disease. Particular compounds described herein exhibit selective inhibitory activity against CBP compared with BRD4.