Rukobia (Fostemsavir) - Oral

What Is Rukobia?

Rukobia (fostemsavir) is an oral antiretroviral drug used with other medications to treat human immunodeficiency virus (HIV) infection. It belongs to a drug class known as HIV-1 entry inhibitor/fusion inhibitors.

Rukobia is a gp120 attachment inhibitor that works by blocking specific proteins on the virus’s cell wall’s outer layer from sticking or attaching to your immune cells. It is available by prescription only as a 12-hour extended-release tablet.

Drug Facts

Generic Name: Fostemsavir

Brand Name(s): Rukobia

Drug Availability: Prescription

Administration Route: Oral

Therapeutic Classification: Antiretroviral agent

Available Generically: No

Controlled Substance: N/A

Active Ingredient: Fostemsavir

Dosage Form(s): Extended-release tablet

What Is Rukobia Used For?

Rukobia (fostemsavir) is combined with other antiretrovirals to treat HIV infection. It is used in people with HIV resistance to several antiviral drugs and whose previous drug treatment has failed. Fostemsavir keeps the viral load below the detection threshold and prevents pregnant individuals from passing HIV to their babies.

Rukobia (Fostemsavir) Drug Information : A person's lymph nodes and part of the immune system

Verywell / Zoe Hansen

How to Take Rukobia

Take one tablet of Rukobia by mouth twice daily with or without food. Swallow the tablets whole. Do not chew, break, or crush them.


Store this drug in a dry place at room temperature (68 to 77 degrees F). Occasionally, you may store it between cool and mildly hot temperatures (59 to 86 degrees F). Do not store it in your bathroom. Keep Rukobia away from the reach of children and pets.

Any unused or expired medication should be disposed of at a proper drug take-back location. Ask your pharmacist about the best ways to dispose of your medicine. Check out local take-back programs in your area.

How Long Does Rukobia Take to Work?

Rukobia takes two hours to peak in your system. However, taking it with a high-fat meal improves drug exposure compared with fasting.

What Are the Side Effects of Rukobia?

This is not a complete list of side effects, and others may occur. A healthcare provider can advise you on side effects. If you experience other effects, contact your pharmacist or a healthcare provider. You may report side effects to the Food and Drug Administration (FDA) at or 1-800-FDA-1088.

Common Side Effects

Any drug may cause side effects. However, some people taking Rukobia may experience some or no adverse effects.

Side effects include:

These are only a few of the drug's possible side effects. If you have any concerns about side effects, contact your healthcare provider. Get medical treatment if any side effects concern you or do not go away.

Severe Side Effects

If you have any severe side effects, contact your healthcare provider right away. Call 911 if you have a medical emergency or your symptoms seem to be life-threatening. Serious side effects of Rukobia can include:

Report Side Effects

Rukobia may cause other side effects. Call your healthcare provider if you have any unusual problems while taking this medication.

If you experience a serious side effect, you or your healthcare provider may send a report to the FDA's MedWatch Adverse Event Reporting Program or by phone (800-332-1088).

Dosage: How Much of Rukobia Should I Take?

Drug Content Provided and Reviewed by IBM Micromedex®

The dose of this medicine will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of this medicine. If your dose is different, do not change it unless your doctor tells you to do so.

The amount of medicine that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.

  • For oral dosage form (extended-release tablets):
    • For treatment of HIV infection:
      • Adults—600 milligrams (mg) 2 times a day.
      • Children—Use and dose must be determined by your doctor.


Rukobia may raise the blood level of ethinyl estradiol used as birth control, increasing the risk for blood clots (thromboembolism). Hence, the maximum daily dose of ethinyl estradiol when used with Rukobia is 30 micrograms.

Also, Rukobia increases the levels of HMG-CoA reductase inhibitors (statins) in the body. It may increase statin-related side effects, including muscle breakdown (rhabdomyolysis). If you experience muscle aches and pains, your healthcare provider may lower the dose of your statins while on this drug.

In general, taking antiretroviral therapy (ART) during pregnancy has been linked to adverse pregnancy effects, such as low birth weight, preterm labor, and stillbirth. Since the benefits of using ART outweighs its risks, people who are pregnant should continue taking their medicine as directed by their healthcare provider. All infants who are exposed to Rukobia should be monitored for any abnormalities, including heart issues.

Missed Dose

Take the missed dose once you remember. If your next dose is too close, skip the missed dose. Return to your usual dosing schedule. Do not double the amount or take extra doses. If you are not sure of what to do if you miss a dose, call your healthcare provider.

Overdose: What Happens If I Use Too Much Rukobia?

Overdose symptoms may include a fast heartbeat or irregular heartbeat.

What Happens If I Overdose on Rukobia?

If you think you or someone else may have overdosed on Rukobia, call a healthcare provider or the Poison Control Center (800-222-1222).

If someone collapses or isn't breathing after taking Rukobia, call 911 immediately.


Drug Content Provided and Reviewed by IBM Micromedex®

It is very important that your doctor check your progress at regular visits to make sure that this medicine is working properly. Blood tests may be needed to check for unwanted effects.

Do not use this medicine together with carbamazepine (Tegretol®), enzalutamide (Xtandi®), mitotane (Lysodren®), phenytoin (Dilantin®), rifampin (Rifadin®), or St. John’s wort.

Your immune system may get stronger when you start using HIV medicines. Tell your doctor right away if you or your child notice any changes in your health. Sometimes the immune system will start to fight infections that were hidden in your body, such as pneumonia, herpes, or tuberculosis. Autoimmune disorders (including Graves disease, polymyositis, and Guillain-Barré syndrome) may also occur.

Contact your doctor right away if you have any changes to your heart rhythm. You might feel dizzy or faint, or you might have a fast, pounding, or uneven heartbeat. Make sure your doctor knows if you had a heart rhythm problem, such as QT prolongation.

This medicine does not treat hepatitis B or C virus infection. You should continue to take medicine for your hepatitis B or C infection during treatment with fostemsavir. Your hepatitis B infection may become active again if you stop your anti-hepatitis B treatment. Your doctor may also do blood tests to check your liver during treatment.

This medicine does not decrease the risk of transmitting the HIV infection to others through sexual contact or by contaminated blood. Make sure you understand and practice safe sex, even if your partner also has HIV. Avoid sharing needles with anyone. If you have any questions about this, check with your doctor.

Do not take other medicines unless they have been discussed with your doctor. This includes prescription or nonprescription (over-the-counter [OTC]) medicines and herbal or vitamin supplements.

What Are Reasons I Shouldn't Take Rukobia?

Do not take Rukobia if you have hypersensitivity to fostemsavir or any part of its formulation.

Avoid taking Rukobia if you are on strong CYP3A4 inducers such as:

What Other Medications Interact With Rukobia?

Taking Rukobia with specific drugs may increase the levels of either drug, which may cause you to have more severe side effects. Avoid taking the following medications with Rukobia:

  • Hycamtin (topotecan)
  • Orilissa (elagolix)
  • Zepatier (elbasvir and grazoprevir)
  • Votrient (pazopanib)
  • Yupelri (revefenacin)
  • Mitotane
  • St. John's Wort
  • Strong CYP3A4 inducers, such as carbamazepine, phenytoin, and rifampin

Other medications may require a dosage adjustment if taken with Rukobia, including:

  • Ethinyl estradiol
  • Statins including rosuvastatin, atorvastatin, and fluvastatin, among others

What Medications Are Similar?

There are three other HIV-1 entry inhibitors similar to Rukobia:

  • Selzentry (maraviroc)
  • Fuzeon (enfuvirtide)
  • Trogarzo (ibalizumab)

Other drugs used to treat HIV infection include:

This list lists drugs also prescribed to treat HIV infections. It is NOT a list of medicines recommended to take with Rukobia. Do not take these drugs together unless your healthcare provider tells you to. If you have any problems, talk to your healthcare provider.

Frequently Asked Questions

  • What is Rukobia used to treat?

    Rukobia is used to treat HIV infections.

  • What are the common side effects of Rukobia?

    The common side effects of Rukobia are:

    • Too much cholesterol in the blood
    • Elevated bilirubin
    • Diarrhea
    • Feeling tired or weak
    • Upset stomach
    • Headache
  • What should I do if I miss a dose of Rukobia?

    Take the missed dose once you think of it. Skip the missed dose if it is too close to your next dose. Return to your regular dosing schedule. Do not take extra doses or double the amount.

  • How soon does Rukobia begin to work?

    Rukobia takes two hours to reach its peak in your body. Taking this medicine with a high-fat meal increases drug exposure compared with fasting.

How Can I Stay Healthy While Taking Rukobia?

Tell your healthcare provider about all your current medications, including over-the-counter (OTC) drugs, natural products, and vitamins. Some OTC drugs like St. John’s Wort can affect how your Rukobia works.

Remember that Rukobia is not a cure for HIV. Continue to practice safer sex. Do not share needles, razors, or toothbrushes.

If you become pregnant while on this drug, enroll as soon as possible in the Antiretroviral Pregnancy Registry (1-800-258-4263 or Stay connected and get involved in HIV support groups near you for more mental and moral support.

Medical Disclaimer

Verywell Health's drug information is meant for educational purposes only and is not intended to replace medical advice, diagnosis, or treatment from a healthcare provider. Consult your healthcare provider before taking any new medication(s). IBM Watson Micromedex provides some of the drug content, as indicated on the page.

2 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Food and Drug Administration. Rukobia label.

  2. Kozal M, Aberg J, Pialoux G, et al. Fostemsavir in adults with multidrug-resistant HIV-1 infection. New England Journal of Medicine. 2020;382(13):1232-1243. doi:10.1056/NEJMoa1902493

By Queen Buyalos, PharmD
Queen Buyalos is a pharmacist and freelance medical writer. She takes pride in advocating for cancer prevention, overall health, and mental health education. Queen enjoys counseling and educating patients about drug therapy and translating complex ideas into simple language.