Having found that the performance of the HB model varies greatly between different protein targets in the PDBbind Test Set, we next investigated how well the model generalised to novel binding data from outside the PDBbind database. To do this, we created and used used the Updated DUD-E Diverse Subset of targets: serine/threonine-protein kinase AKT (AKT1), cytochrome P450 3A4 (CP3A4), glucocorticoid receptor (GCR), HIV-1 protease (HIVPR), HIV-1 reverse transcriptase (HIVRT), and kinesin-like protein 1 (KIF11).