Dear Healthcare Provider,

We are writing to inform you of an important update regarding TAVNEOS® (avacopan), which was approved by the U.S. Food and Drug Administration (FDA) in Oct 2021 for the adjunctive treatment of adult patients with severe active anti-neutrophil cytoplasmic autoantibody (ANCA)-associated vasculitis (AAV) in combination with standard therapy including glucocortocoids.1 TAVNEOS was developed by ChemoCentryx, Inc. Amgen acquired ChemoCentryx in Oct 2022, after TAVNEOS had been on the market for a year.

On January 16th, 2026, the FDA requested that ChemoCentryx voluntarily withdraw TAVNEOS from the U.S. market. The FDA raised concerns about the process followed by ChemoCentryx to re-adjudicate primary endpoint results for 9 of the 331 patients in the ADVOCATE trial. Hepatotoxicity, which is a known infrequent risk of TAVNEOS treatment for AAV, was also raised in the context of the benefit-risk profile of the medicine. Amgen is not aware of any issues with the underlying patient data and after review of the relevant clinical data and years of real-world evidence, Amgen is confident that TAVNEOS demonstrates effectiveness and a favorable benefit-risk profile.

On January 28th, 2026, following the FDA regulatory process, Amgen informed the FDA that it did not intend to withdraw TAVNEOS from the market. Amgen is working with the FDA to determine a path forward, while keeping patient safety, needs, and support at the forefront.

We would like to take this opportunity to provide a brief review of some of the important evidence supporting the favorable benefit-risk profile of TAVNEOS.

Efficacy and Safety Profile

  • The Phase 3 ADVOCATE trial demonstrated that, in combination with standard therapy in each arm, the TAVNEOS arm was noninferior to the prednisone taper arm in achieving remission at week 26 (72.3% vs 70.1%, p<0.001 for noninferiority) and superior in sustaining remission at week 52 (65.7% vs 54.9%, p<0.001 for noninferiority; p=0.007 for superiority).2
  • Secondary outcomes* showed that the TAVNEOS arm had less glucocorticoid exposure and glucocorticoid toxicity, fewer relapses, greater improvement in estimated glomerular filtration rate, and better physical and mental health-related quality of life metrics over 52 weeks.2-5
  • An integrated safety analysis of two Phase 2 trials (CLEAR and CLASSIC) and one Phase 3 trial (ADVOCATE) included 239 patients comprising the avacopan group and 200 patients not receiving avacopan (the non-avacopan group). The overall exposure-adjusted rates of AEs and SAEs were lower in the avacopan group versus the non-avacopan group.6
  • Due to observations of abnormality on liver function testing among some patients receiving TAVNEOS in clinical trials, liver injury is an important identified risk of avacopan and described under Warnings and Precautions in the U.S. Prescribing Information (USPI), which includes recommendations for regular liver test panel monitoring for patients receiving TAVNEOS. Other Warnings and Precautions include serious hypersensitivity reactions, hepatitis B virus reactivation, and serious infection.1

Ongoing Commitment to Patient Safety

Amgen remains committed to patient safety with its routine safety surveillance and signal detections activities. Amgen continues to conduct a multi-country, FDA-required post-marketing study as well as multiple U.S.-based real-world observational studies to further characterize the effectiveness and safety profile of TAVNEOS. Additional ongoing studies in Europe and Japan are also prospectively monitoring patients receiving TAVNEOS for safety events.

Based on robust clinical and real-world data demonstrating efficacy and effectiveness with a favorable benefit–risk profile, Amgen remains confident that TAVNEOS represents an important treatment option for patients with severe, active ANCA-associated vasculitis (GPA and MPA), rare, serious autoimmune diseases with limited therapeutic alternatives.

Amgen is evaluating next steps with the FDA to determine a path forward, while keeping patient safety, needs, and support at the forefront. We will inform you of any further updates that impact the availability of TAVNEOS for patients with severe active GPA and MPA. Healthcare providers should refer to the USPI guidance for important safety information related to TAVNEOS, including recommendations for liver test panel monitoring. Any suspected adverse events should be reported to +1 805-447-3505 or +1-800-772-6436 (+1-800-77-Amgen) or the FDA (1-800-FDA-1088, www.fda.gov/medwatch). For questions, contact Medical Information at +1-800-772-6436 (+1-800-77-Amgen) or www.amgenmedinfo.com.

We are providing TAVNEOS Patient FAQs to support your discussions with patients, which you may share at your discretion.

Sincerely,

Amgen Medical Affairs


* Prespecified secondary endpoints not adjusted for multiplicity and should be considered exploratory. Results should be interpreted with caution.


INDICATION

TAVNEOS (avacopan) is indicated as an adjunctive treatment of adult patients with severe active anti- neutrophil cytoplasmic autoantibody (ANCA)-associated vasculitis (granulomatosis with polyangiitis [GPA] and microscopic polyangiitis [MPA]) in combination with standard therapy including glucocorticoids. TAVNEOS does not eliminate glucocorticoid use.

IMPORTANT SAFETY INFORMATION

CONTRAINDICATIONS

Serious hypersensitivity to avacopan or to any of the excipients.

WARNINGS AND PRECAUTIONS

Hepatotoxicity: Serious cases of hepatic injury have been observed in patients taking TAVNEOS, including life-threatening events. Obtain liver test panel before initiating TAVNEOS, every 4 weeks after start of therapy for 6 months and as clinically indicated thereafter. Monitor patients closely for hepatic adverse reactions, and consider pausing or discontinuing treatment as clinically indicated (refer to section 5.1 of the Prescribing Information). TAVNEOS is not recommended for patients with active, untreated, and/or uncontrolled chronic liver disease (e.g., chronic active hepatitis B, untreated hepatitis C, uncontrolled autoimmune hepatitis) and cirrhosis. Consider the risks and benefits before administering this drug to a patient with liver disease.

Serious Hypersensitivity Reactions: Cases of angioedema occurred in a clinical trial, including 1 serious event requiring hospitalization. Discontinue immediately if angioedema occurs and manage accordingly. TAVNEOS must not be readministered unless another cause has been established.

Hepatitis B Virus (HBV) Reactivation: Hepatitis B reactivation, including life-threatening hepatitis B, was observed in the clinical program. Screen patients for HBV. For patients with evidence of prior infection, consult with physicians with expertise in HBV and monitor during TAVNEOS therapy and for 6 months following. If patients develop HBV reactivation, immediately discontinue TAVNEOS and concomitant therapies associated with HBV reactivation, and consult with experts before resuming.

Serious Infections: Serious infections, including fatal infections, have been reported in patients receiving TAVNEOS. The most common serious infections reported in the TAVNEOS group were pneumonia and urinary tract infections. Avoid use of TAVNEOS in patients with active, serious infection, including localized infections. Consider the risks and benefits before initiating TAVNEOS in patients with chronic infection, at increased risk of infection, or who have been to places where certain infections are common.

ADVERSE REACTIONS

The most common adverse reactions (≥5% of patients and higher in the TAVNEOS group vs. prednisone group) were nausea, headache, hypertension, diarrhea, vomiting, rash, fatigue, upper abdominal pain, dizziness, blood creatinine increased, and paresthesia.

DRUG INTERACTIONS

Avoid co-administration of TAVNEOS with strong and moderate CYP3A4 enzyme inducers. Reduce TAVNEOS dose when co-administered with strong CYP3A4 enzyme inhibitors to 30 mg once daily. Consider dose reduction of CYP3A4 substrates when co-administering TAVNEOS. Coadministration of avacopan and 40 mg simvastatin increases the systemic exposure of simvastatin. While taking TAVNEOS, limit simvastatin dosage to 10 mg daily (or 20 mg daily for patients who have previously tolerated simvastatin 80 mg daily for at least one year without evidence of muscle toxicity). Consult the concomitant CYP3A4 substrate product information when considering administration of such products together with TAVNEOS.

TAVNEOS is available as a 10 mg capsule.

Please see Full Prescribing Information and Medication Guide for TAVNEOS.

To report a suspected adverse event, call 1-833-828-6367. You may report to the FDA directly by visiting www.fda.gov/medwatch or calling 1-800-332-1088.


References

  1. TAVNEOS® (avacopan) prescribing information, Amgen.
  2. Jayne DRW, Merkel PA, Schall TJ, Bekker P. N Engl J Med. 2021;384:599-609.
  3. Jayne DRW, et al. N Engl J Med. 2021;384:599-609; supplementary appendix.
  4. Data on file, Amgen; [1]; 2020.
  5. Strand V, et al. Lancet Rheumatol. 2023;5:e451-e460.
  6. Merkel PA, George MD, Yue H, et al. ACR Open Rheumatol. 2025;7:e70001.