Tenofovir Alafenamide: A Complete Overview

Tenofovir Alafenamide is a prescription antiviral medication used to treat chronic hepatitis B virus (HBV) infection in adults and children ages 6 and older weighing at least 25 kg.

If you or someone you know has been prescribed this medication — or if you're researching treatment options for hepatitis B — this guide covers everything you need to know, including what it is, how it works, how to take it, and how much it costs in 2026.

What Is Tenofovir Alafenamide?

Tenofovir Alafenamide (often abbreviated as TAF) is a nucleotide reverse transcriptase inhibitor (NtRTI) manufactured by Gilead Sciences. It is sold under the brand name Vemlidy as a standalone product for hepatitis B treatment.

TAF is also used as a component in several combination HIV medications, including Descovy, Biktarvy, Genvoya, Odefsey, and Symtuza. However, Vemlidy (the standalone TAF product) is specifically approved for hepatitis B.

Tenofovir Alafenamide is not a controlled substance and does not carry a DEA schedule designation.

It's important to distinguish TAF from the older medication Tenofovir Disoproxil Fumarate (TDF), sold as Viread. Both are prodrugs that convert to the active drug tenofovir in the body, but TAF delivers the active drug more efficiently, which allows for a lower dose and is associated with fewer kidney and bone side effects. Learn more about how Tenofovir Alafenamide works.

What Is Tenofovir Alafenamide Used For?

Tenofovir Alafenamide (Vemlidy) is FDA-approved for:

• Treatment of chronic hepatitis B virus (HBV) infection in adults and pediatric patients ages 6 and older weighing at least 25 kg with compensated liver disease.

Chronic hepatitis B is a long-term infection of the liver caused by the hepatitis B virus. Without treatment, it can lead to serious complications including cirrhosis, liver failure, and liver cancer. Tenofovir Alafenamide works by suppressing the virus to very low or undetectable levels, which helps protect the liver from further damage.

As part of combination products, TAF is also used in the treatment and prevention of HIV-1, but Vemlidy alone should never be used to treat HIV.

How Is Tenofovir Alafenamide Taken?

Tenofovir Alafenamide comes as a 25 mg oral tablet. Here's how to take it:

• Dose: One 25 mg tablet once daily
• With food: Always take Vemlidy with food to increase absorption
• Swallow whole: Do not crush, break, or chew the tablet
• Storage: Store below 86°F (30°C) in the original container with the cap tightly closed
• Consistency: Take it at the same time each day to maintain steady drug levels

If you miss a dose, take it as soon as you remember (with food). If it's almost time for your next dose, skip the missed dose and continue your regular schedule. Do not take two doses at once.

Important: Never stop taking Tenofovir Alafenamide without talking to your doctor first. Stopping suddenly can cause severe hepatitis B flare-ups.

Who Should Not Take Tenofovir Alafenamide?

Tenofovir Alafenamide is not right for everyone. You should not take Vemlidy if you:

• Have decompensated liver disease (Child-Pugh B or C)
• Have end-stage renal disease and are not receiving chronic hemodialysis
• Are co-infected with HIV-1 — Vemlidy alone can lead to HIV-1 resistance. Patients must be tested for HIV before starting treatment. If you have both HBV and HIV, your doctor will prescribe a combination regimen that treats both.

Tell your doctor about all medications you take, including supplements and over-the-counter products. Certain drugs like Rifampin, Carbamazepine, Phenytoin, and St. John's Wort can reduce the effectiveness of Tenofovir Alafenamide. For a complete list, see our guide on Tenofovir Alafenamide drug interactions.

How Much Does Tenofovir Alafenamide Cost?

The cost of Tenofovir Alafenamide depends on your insurance coverage and the pharmacy you use:

• Cash price (without insurance): $1,500 to $1,800 per month for 30 tablets of brand-name Vemlidy
• Generic availability: As of early 2026, no generic version of Tenofovir Alafenamide is marketed in the United States, though the FDA has approved generic manufacturing
• Insurance: Most commercial insurance and Medicare Part D plans cover Vemlidy, though prior authorization may be required. Some plans may require step therapy through the older medication Tenofovir Disoproxil Fumarate (TDF) first.

Ways to Save

• Gilead co-pay assistance: Commercially insured patients may pay as little as $0 per month. Call 1-855-769-7284.
• Gilead Advancing Access: Free medication for qualifying uninsured or underinsured patients. Call 1-800-226-2056 or visit gileadadvancingaccess.com.
• NeedyMeds and RxAssist: These organizations list additional patient assistance programs.

For a more detailed look at savings options, read our complete guide to saving money on Tenofovir Alafenamide.

Final Thoughts

Tenofovir Alafenamide (Vemlidy) is an effective, well-tolerated treatment for chronic hepatitis B. It offers advantages over the older formulation (TDF) with fewer kidney and bone side effects, and it's taken as a simple once-daily tablet with food.

If you've been prescribed Tenofovir Alafenamide and need help finding it in stock or at an affordable price, Medfinder can help you search pharmacies near you. And if you're looking for a prescriber, check out our guide on how to find a doctor who can prescribe Tenofovir Alafenamide.