FG 2216 is an erythropoietic small molecule prolyl hydroxylase inhibitor, originally developed by FibroGen, that is undergoing development for the treatment of anemia. PDH inhibitor FG-2216 was orally bioavailable and induced significant and reversible EPO induction in vivo. Chronic oral dosing in male rhesus macaques was well tolerated, significantly increased erythropoiesis, and prevented anemia induced by weekly phlebotomy. Furthermore, modest increases in HbF-containing red cells and reticulocytes were demonstrated by flow cytometry. FG 2216 had been in phase II clinical trials for the treatment of anemia, however, all researchers on this drug candidate were discontinued.