Fibrogen Inc. and its co-development partners for roxadustat, Astrazeneca plc and Astellas Pharma Inc., were dealt a major blow May 5 as the oral hypoxia-inducible factor prolyl hydroxylase inhibitor failed to meet its primary efficacy endpoint in a phase III trial in patients with anemia caused by transfusion-dependent lower-risk myelodysplastic syndromes (MDS).