Amgen (AMGN.US) hired Duke Clinical Research Institute to independently review and ensure the star drug Tavneos remains on the market.

After the FDA proposed to withdraw the rare disease drug Tavneos from the market due to data manipulation and safety concerns, Amgen has hired the Duke Clinical Research Institute to independently reassess key clinical data in an attempt to turn things around for this product with annual sales of approximately $500 million. Amgen disclosed this arrangement in a letter to the FDA's Center for Drug Evaluation and Research on June 1, which was made public on the regulatory agency's website on Thursday. The letter mentioned that since February of this year, the Duke Clinical Research Institute has initiated an "independent and fully blinded redetermination" to review the major endpoint results supporting the approval of Tavneos in the ADVOCATE late-stage clinical study. Amgen plans to submit detailed reanalyzed data to the FDA by June 29 at the latest as supportive evidence that the benefits of the drug outweigh the risks. Tavneos (generic name: avacopan) was approved by the FDA in October 2021 for the treatment of severe active anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis, a rare autoimmune disease that can cause inflammation of small blood vessels leading to severe damage to the kidneys and lungs. Amgen acquired the drug when it purchased ChemoCentryx for $3.7 billion in 2022, and the current annual sales are around $500 million. In April of this year, the FDA formally proposed to withdraw the approval of Tavneos citing reasons such as false statements in the original submission, insufficient evidence of drug efficacy, and a series of safety signals. According to information from the FDA's Center for Drug Evaluation and Research, the regulatory agency has confirmed 76 cases of serious drug-induced liver injury related to Tavneos, including 8 deaths, with some cases also experiencing severe bile duct loss syndrome. Earlier, the FDA had stated that any new independent analysis of Tavneos data would not be statistically appropriate and would not "rescue" the study that was already questioned. Safety concerns are not limited to the United States. A safety notification released by Amgen's market partner in Japan, Kissei Pharmaceutical, in May of this year showed that approximately 20 patients treated with Tavneos in Japan have died from serious liver dysfunction, although the specific role of the drug in these cases is not clear. Additionally, the medical journal that initially published the ADVOCATE study results has also launched an independent investigation into the allegations of data manipulation. Facing numerous doubts, Amgen emphasized in the letter that the company believes the benefits of Tavneos outweigh the risks and that withdrawing the drug from the market "does not serve the best interests of patients." An Amgen spokesperson responded that the company will carefully review the findings of the Duke Clinical Research Institute and continue to maintain appropriate communication with regulatory agencies, researchers, and the medical community. The Duke Clinical Research Institute declined to comment on the matter.