The FDA’s independent Cardiovascular and Renal Drugs Advisory Committee (CRDAC) voted against approving Roxadustat from FibroGen, which would be a novel treatment of anemia resulting from chronic kidney disease (CKD).

Roxadustat is an oral hypoxia-inducible factor prolyl hydroxylase (HIF-PH) inhibitor.

FibroGen’s CEO said in a statement that the company believes scientific evidence warrants approval of the U.S.

Regulators in other countries, including China, Japan, Chile and South Korea, have approved Roxadustat.

An FDA briefing document on the drug released earlier this week underscored the drug’s efficacy but questioned its safety in CKD patients. Regulators pointed to the possibly elevated risk of blood clots and seizures stemming from the drug compared to Amgen’s Epogen (epoetin alfa), which J&J also markets as Procrit. Such risks are “evident even against epoetin alfa, which is itself known to pose these risks,” the FDA briefing note concluded. “Other signals of concern include serious adverse events of hypoglycemia, gastroenteritis and pancreatitis.”

In April, FibroGen announced it was launching a comprehensive internal review after presenting erroneous safety data about the drug. As it disclosed the “post-hoc changes to the stratification factors,” it provided analyses with pre-specified stratification factors.

AstraZeneca announced in 2013 that it was helping FibroGen develop Roxadustat, which was then known as FG-4592.

Astellas acquired the rights to FG-4592 in Europe, Commonwealth of Independent States (CIS), Middle East and South Africa in 2006.