PFI‐3 was developed as a highly selective small molecule bromodomain inhibitor of the BRG1 and BRM subunits of the SWI/SNF complex, which has minimal ‘off‐target’ effects in primary human cells and no evidence of toxicity on the NCI‐60 panel of tumour cell lines.18, 19. This evidence concerns the gene SMARCA2 and neoplasm.