FDA calls for an advisory meeting for anemia drug from FibroGen
The FDA will hold an advisory meeting to review the new drug application for roxadustat, days ahead of the agency’s planned date for approval of the anemia drug, according to a company press release.
Last December, the FDA announced it was delaying a final review of the oral, small molecule hypoxia-inducible factor prolyl hydroxylase (HIF-PH) inhibitor for 3 months and set a new Prescription Drug User Fee Act action date for the drug of March 20.
FibroGen Inc. and AstraZeneca are seeking approval of the drug for treating anemia in patients with chronic kidney disease. According to the release, the companies have not heard when the FDA Cardiovascular and Renal Drugs Advisory Committee will take place.
“While disappointed with the news today, FibroGen and AstraZeneca are committed to working with the FDA to bring roxadustat to patients with anemia of CKD in the U.S. as soon as possible,” Enrique Conterno, CEO of FibroGen said. “We continue to be confident in the efficacy and safety profile of this potential new medicine based on positive results from a global phase 3 program encompassing more than 8,000 patients.”
The announcement on March 4 about the planned advisory committee meeting sent the stock price of FibroGen down to $33.27 per share after hitting a high of $57.20 on February 12.
FibroGen also responded to a citizen’s petition filed with the FDA by the law firm Epstein Becker & Green P.C. asking the agency to request more cardiovascular safety and mortality data from use of the drug during clinical trials before approving roxadustat, and requested the FDA include a box warning about the safety risks of the drug.
“Phase  clinical program data released by the roxadustat NDA applicant demonstrate that roxadustat poses an increased risk of adverse cardiovascular outcomes and mortality in comparison to the current standard of care, in particular, for patients who are stable on dialysis,” according to the anonymous citizen’s petition.
“Moreover, data released to date fail to demonstrate that roxadustat provides a meaningful treatment benefit over the existing standard of care for [non-dialysis dependent chronic kidney disease, NDD-CKD] patients,” according to the petition. “Roxadustat has only been demonstrated to be non-inferior to placebo in this population; however, any meaningful correction of anemia would be expected to produce better cardiovascular safety and all-cause mortality outcomes than no anemia correction at all.”
In response to the petition, R. Wayne Frost, PharmD, JD, senior vice president of regulatory affairs and medical writing for FibroGen, said the petition “is without scientific or legal basis, and bears all of the hallmarks of citizen petitions that are submitted with the intent of delaying competition.
“ ... [D]espite the petitioner’s erroneous claims, placebo is an appropriate comparator for a study in NDD-CKD, as in the 12 months prior to dialysis initiation less than 15% of CKD patients receive treatment with erythropoietin stimulating agents (ESA), while the average hemoglobin level at dialysis initiation is as low as 9.3 g/dL (USRDS Annual Data Report 2020),” Frost said in the response. “With respect to the use of iron supplementation in this population, iron therapy was permitted as a concomitant treatment in FibroGen’s phase 3 NDD-CKD studies.
“In addition to cardiovascular safety, reduction of transfusion is a fundamental aim of anemia treatment, as transfusion carries with its significant safety risks for the patient. Importantly, in each of the phase 3 NDD-CKD clinical studies, the proportion of patients requiring red blood cell transfusion was lower in patients treated with roxadustat,” Frost said.
The company said roxadustat has been approved in China, Japan and Chile for the treatment of anemia of CKD in both adult patients with NDD and DD.