Pronunciation: len-a-cap-a-vir
Generic name: lenacapavir
Brand names: Sunlenca, Yeztugo
Dosage form: tablets for oral use (300 mg), injection for subcutaneous use in a single-dose vial (463.5 mg/1.5 mL)
Drug class: Miscellaneous antivirals

Medically reviewed by Carmen Pope, BPharm. Last updated on June 23, 2025.

What is lenacapavir?

Lenacapavir is used to treat HIV-1 infection (in combination with other antivirals) or for HIV-1 PrEP, depending on the brand.

• The Sunlenca brand of lenacapavir is used in combination with other antiretrovirals to treat HIV-1 infection in heavily treatment-experienced adults with multidrug-resistant HIV-1, whose current antiretroviral regimen is failing due to resistance, intolerance, or safety considerations. 
• The Yeztugo brand of lenacapavir is used to reduce the risk of getting HIV-1 (HIV-1 PrEP) in adults and adolescents who weigh at least 77 pounds (at least 35 kg). 
• Both brands of lenacapavir are made by Gilead Sciences.

The initial dose of lenacapavir for HIV-1 treatment or PrEP consists of lenacapavir injections and tablets, followed by 2 lenacapavir injections every 6 months (twice a year) thereafter.

Lenacapavir targets HIV-1 by attaching to specific binding sites on capsid proteins with strong binding affinity (KD=1.4nM). It works by disrupting the virus at multiple points: preventing viral DNA from entering the cell nucleus, hampering viral particle assembly and release through reduced capsid protein production, and causing defective capsid structures during formation. Lenacapavir belongs to the drug class called selective HIV-1 capsid inhibitors.

Lenacapavir first gained FDA approval on December 22, 2022, under the Sunlenca brand for HIV-1 treatment. On June 18, 2025, lenacapavir gained FDA approval under the Yeztugo brand for HIV PrEP. There is no generic Sunlenca or Yeztugo.

Side effects

The most common side effects of lenacapavir injection when used for HIV-1 treatment are:

• Nausea
• Injection site reactions (such as swelling, pain, redness, lumps or nodules, thickening or hardening, or itchiness at the injection site).

The most common side effects of lenacapavir injection when used for HIV PrEP are:

• injection site reactions (a lump or bump, pain, skin hardening, swelling, itching, redness, bruising, or warmth at the injection site. This may be felt but not seen, and may take longer to go away than other injection site reactions)
• headache
• nausea.

Serious injection site reactions. Rarely, some lenacapavir injection site reactions caused by improper technique by a healthcare provider can lead to serious injection site reactions like severe skin damage (necrosis) or open sores (ulcers). Tell your healthcare provider if you have any injection site reactions or other side effects.

Related/similar drugs

Warnings and serious side effects

Sunlenca brand of lenacapavir

The following serious side effects have been reported when lenacapavir is used to treat HIV-1 in combination with other antiretrovirals.

Changes in your immune system (Immune Reconstitution Syndrome). This can happen when you start taking HIV-1 medicines. Your immune system may get stronger and begin to fight infections that have been hidden in your body for a long time. Tell your healthcare provider right away if you start having any new symptoms after starting your HIV-1 medicine.

Yeztugo brand of lenacapavir

When used for HIV PrEP (Yeztugo brand), lenacapavir carries a Boxed Warning for the risk of drug resistance with use in people with undiagnosed HIV-1 infection.

• This does not apply when the Sunlenca brand of lenacapavir is used for HIV-1 treatment in combination with other antiretrovirals.

Undiagnosed HIV-1 infection

Before receiving lenacapavir injection to reduce your risk of getting HIV-1, you must be HIV-1 negative to start lenacapavir. You must get tested to make sure that you do not already have HIV-1.

• Do not receive lenacapavir unless you are confirmed to be HIV-1 negative.
• Some HIV-1 tests can miss HIV-1 infection in a person who has recently acquired HIV-1. If you have flu-like symptoms, you could have recently acquired HIV-1. Tell your healthcare provider if you had a flu-like illness within the last month before starting lenacapavir or at any time while receiving lenacapavir. Symptoms of a new HIV-1 infection include:
  • tiredness
  • joint or muscle aches
  • sore throat
  • rash
  • enlarged lymph nodes in the neck or groin
  • fever
  • headache
  • vomiting or diarrhea
  • night sweats.

Risk of other sexually transmitted infections (STIs)

Lenacapavir does not prevent other sexually transmitted infections (STIs).

• Practice safer sex by using a latex or polyurethane condom to reduce the risk of getting STIs.
• Get tested for other STIs such as syphilis, chlamydia, and gonorrhea.
• You must stay HIV-1 negative to keep receiving lenacapavir.

Know your HIV-1 status and the HIV-1 status of your partners.

Ask your partners with HIV-1 if they are taking anti-HIV-1 medicine and have an undetectable viral load.

• An undetectable viral load is when the amount of virus in the blood is too low to be measured in a lab test. To maintain an undetectable viral load, your partners must keep taking HIV-1 medicine as prescribed. Your risk of getting HIV-1 is lower if your partners with HIV-1 are taking effective treatment.

Get tested for HIV-1 with each lenacapavir injection or when your healthcare provider tells you. You should not miss any HIV-1 tests. If you get HIV-1 and continue receiving lenacapavir because you do not know you have HIV-1, the HIV-1 may become harder to treat.

• If you think you were exposed to HIV-1, tell your healthcare provider right away. They may want to do more tests to be sure you do not have HIV-1.

Get information and support to help reduce sexual behaviors associated with the risk of getting HIV-1.

Follow the lenacapavir dosing schedule, which includes returning to a healthcare provider for your scheduled injections every 6 months. Missing injections or tablets increases your risk of getting HIV-1.

If you get HIV-1, you will need to immediately take other medicines to treat HIV-1. Lenacapavir, Yeztugo brand, is not for HIV-1 treatment.

• If you have HIV-1 and receive only lenacapavir, over time your HIV-1 may become harder to treat.
• It is not known if lenacapavir is safe and effective for HIV PrEP in children weighing less than 77 pounds (less than 35 kg).

These are not all of the possible side effects of lenacapavir. Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.

Before receiving

Do not receive or take lenacapavir for HIV-1 treatment (Sunlenca brand) if you also take certain other medicines called strong CYP3A inducers. Ask your healthcare provider if you are not sure. 

Do not receive or take lenacapavir for HIV PrEP (Yeztugo brand) if you have HIV-1 or your HIV status is unknown.

Before receiving lenacapavir, tell your healthcare provider about all your medical conditions, including if you:

• Are pregnant or plan to become pregnant
• Are breastfeeding or plan to breastfeed.

Pregnancy 

Tell your healthcare provider if you become pregnant while or after receiving lenacapavir.

Pregnancy Registry: There is a pregnancy registry for individuals who receive lenacapavir during pregnancy. The purpose of this registry is to collect information about you and your baby's health. Talk with your healthcare provider about how you can take part in this registry.

Breastfeeding 

A small amount of lenacapavir will transfer into breast milk. Talk to your healthcare provider about the best way to feed your baby while you are receiving lenacapavir.

If you are taking lenacapavir for HIV-1 treatment (Sunlenca brand), breastfeeding is not recommended because of the risk of passing HIV-1 to your baby.

How will I receive and take lenacapavir?

Lenacapavir consists of injections and tablets.

• How you take them depends on whether you are taking them for HIV-1 treatment (in combination with other antiretrovirals) or HIV PrEP.
• Your healthcare provider will give you the lenacapavir injections.
• You can take the tablets by mouth with or without food.

Lenacapavir for HIV-1 treatment (Sunlenca brand)

There are two starting options when lenacapavir is used for HIV-1 treatment. Your healthcare provider will decide which one is best for you.

• Lenacapavir injections will be given to you by your healthcare provider under the skin (subcutaneous injection) in your stomach area (abdomen).
• Stay under the care of a healthcare provider during treatment. It is important that you attend your planned appointments to receive your injections.
• Continue to take all of your other HIV-1 medicines as prescribed by your doctor.

Option 1:

• On Day 1, you will receive 2 lenacapavir injections SC and take 2 lenacapavir tablets.
• On Day 2, you will take 2 tablets.
• 6 months (26 weeks) thereafter: 2 injections SC every 6 months (26 weeks) from the date of your last injection.

Option 2:

• Day 1: 2 lenacapavir tablets.
• Day 2: 2 tablets.
• Day 8: 1 tablet.
• Day 15: 2 lenacapavir injections given SC 
• 6 months (26 weeks) thereafter: 2 injections SC every 6 months (26 weeks) from the date of your last injection.

Lenacapavir for HIV PrEP (Yeztugo brand)

Your dosing schedule will start as follows:

• On Day 1, you will receive 2 lenacapavir injections and take 2 lenacapavir tablets.
• On Day 2, you will take 2 lenacapavir tablets.

After completing the start of your dosing schedule, you will receive 2 lenacapavir injections every 6 months (26 weeks) from the date of your last injection.

• Lenacapavir injections will be given to you by your healthcare provider under the skin (subcutaneous injection) in your stomach area (abdomen) or upper thigh.
• Stay under the care of a healthcare provider during treatment. You must attend your planned appointments to receive your injections.
• Continue to practice safe sex by using a latex or polyurethane condom to reduce the risk of getting STIs.

Dosing information

Adult Dose of Lenacapavir for HIV-1 treatment

Initiation with one of two options, followed by once every 6 months maintenance dosing.

Missed dose - If more than 28 weeks since last injection and clinically appropriate to continue Sunlenca, restart initiation from Day 1, using either Option 1 or Option 2.

Dose of Lenacapavir for HIV-1 PrEP

• Day 1: 927 mg by subcutaneous (SC) injection (2 x 1.5 mL injections) and 600 mg orally (2 x 300 mg tablets)
• Day 2: 600 mg orally (2 x 300 mg tablets)
• 6 months (26 weeks) thereafter from the date of the last injection (+/-2 weeks): 927 mg by SC injection (2 x 1.5 mL injections)

Note: Lenacapavir injection is for subcutaneous administration only. Two 1.5 mL injections are required for the complete dose.

What happens if I miss a dose?

Lenacapavir for HIV-1 treatment

If you miss your scheduled injection appointment, call your healthcare provider right away to discuss your treatment options. Missing an injection may cause the HIV-1 virus to change (mutate) and become harder to treat (resistant).

Tell your healthcare provider right away if you stop receiving lenacapavir or stop taking any other antiretroviral medicines. If you stop treatment with lenacapavir, you will need other medicines to treat your HIV-1 infection. If you do not take other HIV-1 medicines, the amount of virus in your blood may increase, and the virus may become harder to treat. Call your healthcare provider right away to discuss your treatment options.

Lenacapavir for HIV PrEP

If you miss or need to delay your scheduled every 6 months injection of lenacapavir by more than 2 weeks, call your healthcare provider right away to discuss your PrEP options.

If you need to delay your scheduled lenacapavir injection appointment, there is the option to temporarily take Yeztugo tablets. You will take 1 lenacapavir tablet by mouth 1 time every 7 days, until your injections resume.

If more than 28 weeks have elapsed since your last injection and tablets have not been taken, your healthcare provider will restart the initiation schedule from Day 1 if clinically appropriate.

It is important to continue receiving lenacapavir as scheduled. Missing lenacapavir injections or tablets may increase your risk of getting HIV-1.

• If you stop receiving lenacapavir, talk to your healthcare provider about other options to reduce the risk of getting HIV-1.

What happens if I take too many lenacapavir tablets?

If you take too many lenacapavir tablets, call your healthcare provider or go to the nearest hospital emergency room right away.

What other drugs will affect this medicine?

Tell your healthcare provider about all the medicines you take, including prescription and over-the-counter medicines, vitamins, and herbal supplements, including St. John’s wort.

Some medicines may interact with lenacapavir. Keep a list of your medicines and show it to your healthcare provider and pharmacist when you get a new medicine. Medicines that may interact with lenacapavir include:

Strong CYP3A inducers (such as rifampin, phenytoin, or phenobarbital) or moderate CYP3A inducers (such as efavirenz, dexamethasone, or St. John's Wort).

Do not start a new medicine without telling your healthcare provider. Your healthcare provider can tell you if it is safe to receive lenacapavir with other medicines. Lenacapavir may affect certain other medicines for up to 9 months after your last injection.

Storage

• Store tablets at room temperature between 68 °F to 77 °F (20 °C to 25 °C).
• The bottle contains a desiccant packet to help keep your medicine dry (protect it from moisture). Keep the desiccant packet in the bottle. Do not eat the desiccant packet.
• Keep the tablets in their original blister pack.
• Keep all medicines out of the reach of children and pets.

Ingredients

Active ingredient: lenacapavir

Inactive ingredients:

• Sunlenca/Yeztugo tablets: copovidone, croscarmellose sodium, magnesium stearate, mannitol, microcrystalline cellulose, and poloxamer 407.
• Sunlenca/Yeztugo tablet film-coating: iron oxide black, iron oxide red, iron oxide yellow, polyethylene glycol, polyvinyl alcohol, talc, and titanium dioxide.
• Sunlenca/Yeztugo injection: polyethylene glycol 300 and water for injection.

Available as 300 mg tablets and 463.5 mg/1.5 mL injection.

Manufacturer

Sunlenca and Yeztugo injections and tablets are manufactured and distributed by Gilead Sciences Inc., Foster City, CA 94404.

Further information

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

Medical Disclaimer