In a study on links between endometriosis and GI conditions, Yang et al identified some candidates genes for drug repurposing [54] highlighting, CCKBR, that encoded a protein targeted by two drugs Proglumide and Netzepide not yet tested in endometriosis patients and PDE4B the product of which is targeted by Pentoxifylline, already being tested for endometriosis (phase III) and IBS (phase IV) in separate trials. The gene discussed is PDE4B; the disease is irritable bowel syndrome.