Avacopan (Tavneos)

How Medicare covers it

Part D (forms used at home). Part A during a covered inpatient stay. No Part B clinician-administered form in the CMS Part B spending file.

What it treats

Severe, active ANCA-associated vasculitis — granulomatosis with polyangiitis (GPA) and microscopic polyangiitis (MPA) — in adults, as an added (adjunctive) treatment used together with standard therapy including glucocorticoids (steroids). Tavneos does not eliminate glucocorticoid use.

What it is for, in depth

Tavneos (avacopan) is an add-on treatment for adults whose ANCA-associated vasculitis is severe and active — the two forms named in the label are granulomatosis with polyangiitis (GPA) and microscopic polyangiitis (MPA), diseases where the immune system attacks small blood vessels and can damage organs such as the kidneys and lungs. It is prescribed on top of standard therapy, which includes glucocorticoid steroids, and the label is clear that it does not remove the need for steroids. In the treatment path it sits alongside the main immune-suppressing treatment rather than replacing it, giving doctors another way to control the vessel inflammation. It comes only as a 10 mg capsule, and the dose is three capsules (30 mg) twice a day with food.

How it works

Avacopan blocks the complement 5a receptor (C5aR). By blocking that receptor it stops the immune signal C5a from switching on and pulling in neutrophils (a type of white blood cell), which is part of what damages blood vessels in ANCA-associated vasculitis.

How it is taken

30 mg by mouth twice a day, with food — that is three 10 mg capsules in the morning and three in the evening. Swallow the capsules whole: do not crush, chew, or open them. If a dose is missed, wait and take the next dose at the usual time; do not double the next dose.

Common side effects

In the phase 3 trial, the side effects that happened in 5% or more of patients and more often with Tavneos than with prednisone were nausea (23.5%), headache (20.5%), high blood pressure (18.1%), diarrhea (15.1%), vomiting (15.1%), rash (11.4%), fatigue (10.2%), upper belly pain (6.6%), dizziness (6.6%), increased blood creatinine (6.0%), and tingling or prickling feelings (paresthesia, 5.4%).

Serious warnings

Liver injury (hepatotoxicity): serious liver damage has occurred, including higher liver enzymes and liver/bile duct events, and after approval vanishing bile duct syndrome (VBDS), a severe liver condition that has included fatal cases, has been reported, so liver blood tests are checked before starting, every 4 weeks for the first 6 months, and as needed after that. Allergic reactions: Tavneos can cause angioedema (swelling that can threaten the airway); it must be stopped at once and never restarted unless another cause is found. Hepatitis B can become active again (HBV reactivation), which can lead to liver failure and death, so patients are screened for hepatitis B before starting. Serious infections, including fatal ones, have been reported — pneumonia and urinary tract infections were the most common — and Tavneos should be avoided during an active serious infection.

Who should be careful

People with liver disease: Tavneos is not recommended for patients with cirrhosis, especially severe liver impairment (Child-Pugh C), or with active, untreated or uncontrolled chronic liver disease such as chronic active hepatitis B, untreated hepatitis C, or uncontrolled autoimmune hepatitis. People with past or current hepatitis B infection need screening and monitoring during treatment and for 6 months after it. People with a chronic or returning infection, a history of a serious or opportunistic infection, exposure to tuberculosis, or time spent in areas where tuberculosis or certain fungal infections are common should weigh the risks and benefits with their doctor first. Anyone with a serious allergic reaction to avacopan or any of its ingredients must not take it.

Major interactions

Strong and moderate CYP3A4 inducers (such as rifampin) lower avacopan levels and should be avoided. Strong CYP3A4 inhibitors (such as itraconazole) raise avacopan levels, so the Tavneos dose is lowered to 30 mg once a day while one is being taken. Avacopan itself is a moderate CYP3A4 inhibitor and raises levels of drugs broken down by CYP3A4: while taking Tavneos, simvastatin should be limited to 10 mg a day (or 20 mg a day for patients who previously tolerated 80 mg a day for at least a year without muscle toxicity), and dose reductions should be considered for other CYP3A4 substrate drugs.

Cost and saving notes

This drug is usually covered under Medicare Part D, often through a specialty pharmacy with prior authorization. If your cost is high, ask your plan about a tier exception. If you have limited income, the Extra Help (Low-Income Subsidy) program can lower your Part D premiums and drug costs. In 2027, your total yearly out-of-pocket spending on Part D drugs is capped at $2,400, and you can ask your plan to spread those costs out in monthly payments through the Medicare Prescription Payment Plan. The maker may also offer a patient support program.

Why it is in its tier

Avacopan (Tavneos) sits on Tier 5 in 96.33% of the plans that list it (2204 of 2288 listing plans). Tier 5 is the specialty tier — instead of a flat copay, patients usually pay a percentage of the drug's cost (coinsurance), which is why specialty drugs feel expensive even with coverage. The data-visible drivers: It is a brand-only product with no generic version in the formulary data, and the CMS dashboard puts its average Part D spending at about $91,847 per beneficiary for 2024 — among the highest-cost drugs in the program, which matches where plans place it. Only 41.64% of Part D plans list it at all, so many readers will find their plan does not list it and covers a similar drug instead. The tier shown is the most common one; individual plans vary.

Sources

• TAVNEOS (AVACOPAN) CAPSULE [CHEMOCENTRYX, INC.] — DailyMed
• MedlinePlus — National Library of Medicine
• MedlinePlus — Avacopan

What official patient guides say

Avacopan fits into your day as a morning-and-evening routine with food: three 10 mg capsules in the morning and three in the evening, at around the same times every day. Swallow the capsules whole with water and do not open, chew, or crush them. Ask your doctor before eating grapefruit or drinking grapefruit juice while you take it. If you miss a dose, skip it and take the next dose at the usual time; do not take a double dose to make up for it. Keep the capsules in their container, tightly closed, at room temperature, away from extra heat and moisture and out of children's reach. In daily life, many people notice nausea, vomiting, stomach pain, diarrhea, headache, dizziness, tiredness, or a rash, especially early on. Keep your regular lab and doctor visits, since your team watches your liver and blood counts while you take this drug along with your other vasculitis treatment.

Source: MedlinePlus — Avacopan

Part D formulary coverage

Source: CMS Prescription Drug Plan Formulary, Pharmacy Network, and Pricing Information Files — Monthly file 2026-10-15 (plan year 2027), file 2027_20261008.zip (data.cms.gov dataset ed1496ea-23e7-41f1-9292-172fa842ccfb): basic drugs formulary file + plan information file, both dated 20261031 inside the zip; downloaded and aggregated 2026-10-30. Medication RxCUI sets resolved through the NLM RxNav (RxNorm) API.

What you pay

A tier is not a price; what you pay depends on your plan, pharmacy, and benefit stage; Extra Help or Medicaid can lower it further.

Sources: CMS Plan Benefit Package + formulary data; CMS NADAC · Checked 2026-11-07

Coverage by plan and tier

Of the 5,495 Medicare drug plans we track for 2027, 2,288 list Avacopan (Tavneos) — 41.6% of plans. Most of those plans put it on Tier 5: 2,204 plans, 96.3% of the plans that list it. Other plans place it on Tier 1 (70 plans), Tier 4 (7 plans) or Tier 3 (6 plans). For example: Aetna Medicare Dual Extra (HMO D-SNP) puts it on Tier 5; Aetna Medicare Dual Extra Care (PPO D-SNP) puts it on Tier 5; Aetna Medicare Value Plus (PPO) puts it on Tier 5. You can compare these plans side by side on our Medicare Advantage hub. A tier is not a price. What you pay also depends on whether you have met your plan';s deductible, whether the drug costs a flat copay or a share of the price, and whether you get Extra Help or Medicaid.

Read next

• Part D in 2027: The $700 Deductible, the $2,400 Cap, and the $35 Insulin Rule
• Extra Help in 2027: Lower Drug Copays and Who Qualifies
• Checking Medicare Savings Programs and Extra Help

Part D spending averages (2024)

Source: CMS Medicare Part D Spending by Drug (Drug Spending Dashboard), release RY26 P04 V10, data through 2024 (DSD_PTD_RY26_P04_V10_DY24_BGM.csv), downloaded 2026-10-30

Companies covering this drug

Part D and Medicare Advantage plan sponsors that list this drug on a formulary, 50 at a time.