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Pronunciation: VEM-lih-dee
Generic name: tenofovir alafenamide
Dosage form: oral tablet
Drug class: Nucleoside reverse transcriptase inhibitors (NRTIs)

Medically reviewed by Carmen Pope, BPharm. Last updated on Apr 3, 2024.

What is Vemlidy?

Vemlidy (tenofovir alafenamide) is an oral, once-daily, antiviral tablet that may be used to treat long-lasting (chronic) hepatitis B virus (HBV) infection in adults and children aged 6 years of age and older and weighing at least 55 pounds (25 kg) with stable (compensated) liver disease.

Vemlidy (tenofovir alafenamide) is a prodrug that is converted inside liver cells to tenofovir and then to its active metabolite which inhibits replication of HBV by incorporation into the viral DNA by HBV reverse transcriptase, which terminates the DNA chain. Vemlidy may lower levels of HBV in your body and may improve the condition of your liver.

Vemlidy was FDA approved on November 10, 2026.


Vemlidy should not be used by itself to treat HIV-1 infection because resistance may develop. Your healthcare provider may conduct tests to test for the presence of HIV-1 infection. Do not share your medicine with anyone else.

If you have hepatitis B, it may get worse (flare-up) if you take Vemlidy and then stop taking it. A “flare-up” is when your HBV infection suddenly returns in a worse way than before.

Do not run out of Vemlidy. Refill your prescription or talk to your healthcare provider before it is all gone. Do not stop taking it without first talking to your healthcare provider.

If you stop taking Vemlidy, your healthcare provider will need to check your health often and do blood tests regularly for several months to check your liver. Tell your healthcare provider about any new or unusual symptoms you may have after you stop taking it.

Your healthcare provider may conduct other tests, for example, to assess your kidney function, or to test your urine for glucose or protein, before starting Vemlidy and regularly thereafter if necessary. Not recommended for people with end-stage kidney disease who are not receiving hemodialysis nor for people with decompensated liver disease (Child-Pugh B or C).

May increase the risk of lactic acidosis or an enlarged liver (hepatomegaly) with steatosis (fat build-up). Your healthcare provider will monitor you for this.

It is not known if Vemlidy is safe and effective in children under 6 years of age or who weigh less than 55 pounds (25kg).

Before taking this medicine

You should not take Vemlidy if you are allergic to tenofovir, Vemlidy, or any of the inactive ingredients in the tablets.

To make sure Vemlidy is safe for you, tell your healthcare provider about all of your medical conditions, including if you:


It is not known if Vemlidy will harm your unborn baby. Tell your healthcare provider if you become pregnant during treatment. There is a pregnancy registry for women who take antiviral medicines during pregnancy. The purpose of this registry is to collect information about the health of you and your baby. Talk with your healthcare provider about how you can take part in this registry.


Vemlidy may pass into your breast milk. Talk with your healthcare provider about the best way to feed your baby.

How should I take Vemlidy?

Take Vemlidy exactly as prescribed by your doctor. Follow all directions on your prescription label and read all medication guides or instruction sheets. Before you start treatment, your doctor may perform tests to make sure you do not have HIV.

Do not change your dose or stop taking Vemlidy without first talking with your healthcare provider. Stay under a healthcare provider's care when taking this medicine.

What happens if I miss a dose?

Do not miss a dose of Vemlidy. When your Vemlidy supply starts to run low, get more from your healthcare provider or pharmacy. This is very important because your HBV infection may get worse (flare-up) if you stop taking Vemlidy.

If you forget to take a dose, take it as soon as you remember.

What happens if I overdose?

If you take too much Vemlidy, call your healthcare provider or go to the nearest emergency room right away.

What should I avoid while taking Vemlidy?

Drinking alcohol may increase your risk of liver damage.

Taking Vemlidy will not prevent you from passing hepatitis B to other people. Practice safe sex and do not share needles with other people.

What are the side effects of Vemlidy?

Get emergency medical help if you have signs of an allergic reaction to Vemlidy such as hives, difficulty breathing, or swelling of your face, lips, tongue, or throat.

Vemlidy may cause serious side effects, including:

The most common side effect of Vemlidy affecting 10% or more people is headache.

Tell your healthcare provider if you have any side effect that bothers you or does not go away. These are not all the possible side effects of Vemlidy. For more information, ask your healthcare provider or pharmacist. Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.

What other drugs will affect Vemlidy?

Tell your healthcare provider about all the medicines you take, including prescription and over-the-counter medicines, vitamins, and herbal supplements. Some medicines may affect how Vemlidy works.

Keep a list of your medicines and show it to your healthcare provider and pharmacist when you get a new medicine. You can ask your healthcare provider or pharmacist for a list of medicines that interact with Vemlidy or refer to the prescribing information. Not all possible interactions are listed here.


Store at room temperature below 86 °F (30 °C) in the original container. Keep the container tightly closed. Vemlidy comes in a child-resistant package but still should be kept out of reach of children.

Vemlidy ingredients

Active ingredients: tenofovir alafenamide

Inactive ingredients: croscarmellose sodium, lactose monohydrate, magnesium stearate, and microcrystalline cellulose.

Film-coating: iron oxide, yellow, polyethylene glycol, polyvinyl alcohol, talc, and titanium dioxide.

Available as a 25mg oral tablet.


 Gilead Sciences, Inc.

Popular FAQ

Vemlidy (tenofovir alafenamide) and Viread (Tenofovir disproxil fumarate) are antiviral medications marketed by Gilead Sciences. They are both prodrugs of tenofovir.

Vemlidy and Viread are similar in terms of their effectiveness, but Vemlidy is effective at a much lower dose than Viread. Less tenofovir ends up in the bloodstream after taking Vemlidy, leading to improved renal and bone laboratory safety parameters compared with Viread.

Vemlidy also has greater plasma stability, enabling it to deliver tenofovir to hepatocytes more efficiently.

Vemlidy and Viread are both used to treat chronic hepatitis B virus (HBV) infection, but Viread is also used in the treatment of human immunodeficiency virus-1 (HIV-1) infection. Continue reading

Biktarvy (bictegravir, emtricitabine and tenofovir alafenamide) can increase cholesterol levels due to the tenofovir alafenamide (TAF) component, but this does not appear to be a frequent or significant side effect. Continue reading

More FAQ

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.