CSL Vifor holds the marketing authorization for Tavneos in the U.K., where the drug is marketed as Avacopan Vifor. It continues to be sold on the U.S. market by Amgen despite concerns raised by the FDA.
The U.K. has stopped allowing the use of rare autoimmune disease therapy Tavneos in new patients, becoming the latest major health regulator to act on concerns about the drug’s benefit-risk profile.
Tavneos is sold as Avacopan Vifor in the U.K. and is marketed there by CSL Vifor. The drug was originally developed by ChemoCentryx and won FDA approval in 2021 for ANCA-associated vasculitis, a systemic disease that can lead to organ damage and failure. Amgen acquired ChemoCentryx for $3.7 billion in 2022, and the pharma remains Tavneos’ owner in the U.S.
In a media release on Tuesday, the U.K.’s Medicines and Healthcare products Regulatory Agency (MHRA) said that the decision to suspend Avacopan Vifor was driven by an assessment of all available evidence for the drug, as well as concerns raised by patients and healthcare professionals regarding “the integrity and reliability of data from the pivotal clinical study underpinning the medicine’s authorization.”
Amgen expressed disappointment with the MHRA’s decision. “We disagree with the MHRA’s decision to withdraw Tavneos from the U.K. market and are deeply concerned about the impact this decision may have on rare disease patients,” a company spokesperson told BioSpace in an email.
“We are disappointed that the MHRA’s interpretation of the data fails to appropriately recognize the totality of evidence supporting the effectiveness and favorable benefit-risk profile of Tavneos,” the spokesperson added, pointing to real-world studies and secondary-endpoint data.
While supply and sale to new patients is no longer allowed, CSL Vifor can still provide the drug to those who are already on Avacopan Vifor as these patients are “safely transitioned” to alternative products. The MHRA has allowed a six-month “managed withdrawal period” after which it will completely revoke the drug’s marketing authorization in the U.K.
The deadline for that withdrawal is currently set for March 1, 2027.
Tavneos’ troubles started in January this year, when the FDA first asked Amgen to voluntarily take the drug off the market, pointing to uncertainties with how ChemoCentryx re-adjudicated the pivotal data that led to Tavneos’ approval. Amgen refused.
The standoff has continued between the pharma and the regulator, and in recent months escalated to involve other territories and parties. Last month, the European Medicines Agency, the main health regulatory body for the European Union, pulled marketing authorization for Tavneos, likewise pointing to “serious breaches” in how the pivotal trial had been conducted. Japan earlier this year also instructed Kissei Pharmaceutical, which markets Tavneos in the country, to add new warnings to the drug alerting prescribers of risks such as liver complications and death.
In June, The New England Journal of Medicine retracted a paper for that same study at the request of two authors. “Without the knowledge of these two authors, the primary end-point assessments in nine patients were readjudicated after database lock and trial unblinding,” the journal wrote at the time.
Amgen has requested a hearing with the FDA over the Tavneos row. The pharma is building its defense of the drug with an independent analysis of pivotal data, supplemented by patient testimonials.
