Drug information

Audio
Pronounce:
Brand Name:
Tybost
Other Names:
COBI, c
Drug Class:
Pharmacokinetic Enhancers (CYP3A Inhibitors)
Drug Image(s): (Click to enlarge)
 
What are the most important things to know about cobicistat? What are the most important things to know about cobicistat?

What are the most important things to know about cobicistat?

 

Cobicistat can cause serious, life-threatening side effects. These include new or worsening kidney problems, including kidney failure and drug interactions.

Cobicistat, when taken with a regimen containing tenofovir disoproxil fumarate, can cause new or worsening kidney problems, including kidney failure. Contact your health care provider right away if you have any of the following symptoms that could be signs of a worsening kidney problem (called Fanconi Syndrome), which may be related to tenofovir-containing drugs:

  • Bone pain that does not go away or gets worse
  • Pain in your arms, hands, legs, or feet
  • Broken bones
  • Muscle pain or weakness

Taking cobicistat and atazanavir or darunavir with certain other medicines can cause serious, life-threatening side effects. Tell your health care provider about all the medicines you take, including prescription and over-the-counter medicines, vitamins, and herbal supplements.

While taking cobicistat, it is important to keep all of your appointments with your health care provider.

What is cobicistat?What is cobicistat?

What is cobicistat?

Cobicistat (brand name: Tybost) is a prescription medicine approved by the U.S. Food and Drug Administration (FDA) for use in adults and children along with the HIV medicines atazanavir (brand name Reyataz) or darunavir (brand name Prezista).

  • When taken with atazanavir, cobicistat is FDA-approved for use in adults and children who weigh at least 77 lb (35 kg).
  • When taken with darunavir, cobicistat is FDA-approved for use in adults and children who weigh at least 88 lb (40 kg).

For more information on the use of cobicistat in people with HIV, please refer to the Guidelines for the Use of Antiretroviral Agents in Adults and Adolescents Living with HIV and the Guidelines for the Use of Antiretroviral Agents in Pediatric HIV Infection.

Cobicistat is not an HIV medicine and does not treat HIV. Even if you take cobicistat and atazanavir or darunavir, you must also take all the HIV medicines prescribed by your health care provider. Do not cut down on, skip, or stop taking cobicistat or any HIV medicines unless your health care provider tells you to.

What should I tell my health care provider before taking cobicistat?What should I tell my health care provider before taking cobicistat?

What should I tell my health care provider before taking cobicistat?

Before taking cobicistat, tell your health care provider:

  • If you are allergic to cobicistat, atazanavir, darunavir, or any other medicines. 
  • If you have kidney problems.
  • If you have liver problems.
  • If you have any other medical conditions.
  • If you are pregnant or plan to become pregnant. Talk to your health care provider about the risks and benefits of taking cobicistat during pregnancy. For more information on the use of cobicistat during pregnancy, please refer to the Recommendations for the Use of Antiretroviral Drugs in Pregnant Women with HIV Infection and Interventions to Reduce Perinatal HIV Transmission in the United States.
  • If you are breastfeeding or plan to breastfeed. For women with HIV in the United States, the Guideline does not recommend breastfeeding. Before your baby is born, or if you are already breastfeeding, talk to your health care provider to discuss alternative options for feeding your baby. 
  • If you are using hormone-based birth control (such as pills, implants, or vaginal rings). Cobicistat may make these forms of birth control less effective. Your health care provider can help you decide how to adjust your birth control while you are taking cobicistat. For more information about using birth control and HIV medicines at the same time, view the HIVinfo HIV and Birth Control infographic.
  • About other prescription and nonprescription medicines, vitamins, nutritional supplements, and herbal products (including St. John's wort) you are taking or plan to take. Cobicistat may affect the way other medicines or products work, and other medicines or products may affect how cobicistat works. Taking cobicistat together with atazanavir or darunavir and certain other medicines may cause serious or life-threatening side effects.
How should I take cobicistat?How should I take cobicistat?

How should I take cobicistat?

Cobicistat comes in tablet form. Each tablet contains 150 mg of cobicistat.

Take cobicistat according to your health care provider’s instructions.

Take cobicistat once each day at the same time you take atazanavir or darunavir. It is important to take these medicines on a regular dosing schedule.

Take cobicistat and atazanavir or darunavir by mouth with food.

If you have taken too much cobicistat, contact your health care provider or local poison control center (1-800-222-1222) right away, or go to the nearest hospital emergency room.

For more information on how to take cobicistat, see the FDA drug label.

What should I do if I forget a dose?What should I do if I forget a dose?

What should I do if I forget a dose?

If you miss a dose of cobicistat, take the missed dose as soon as you remember it. But if it is almost time for your next dose, skip the missed dose and just take your next dose at the regular time. Do not take two doses at the same time to make up for the missed dose.

What side effects can cobicistat cause?What side effects can cobicistat cause?

What side effects can cobicistat cause?

Cobicistat may cause side effects. Some side effects of cobicistat can be serious as noted above. Many side effects from HIV medicines, such as nausea or occasional dizziness, are manageable. See the HIVinfo fact sheet on HIV Medicines and Side Effects for more information.  

When cobicistat is taken with atazanavir, the most common side effects include yellowing of your skin or the whites of your eyes (jaundice) and rash.

Tell your health care provider if you have any side effect that bothers you or that does not go away.

These are not all the possible side effects of cobicistat. To learn more about possible side effects of cobicistat, read the drug label or package insert or talk to your health care provider or pharmacist.

You can report side effects to FDA at 1-800-FDA-1088 (1-800-332-1088) or online.

How should cobicistat be stored?How should cobicistat be stored?

How should cobicistat be stored?

  • Store cobicistat at room temperature, 68°F to 77°F (20°C to 25°C).
  • Keep cobicistat in the container that it came in and keep the container tightly closed. If the container has a small packet of drying agent (called a desiccant), do not remove it. The desiccant protects the medicine from moisture.
  • Do not use cobicistat if the original seal over the container opening is broken or missing.
  • Throw away cobicistat that is no longer needed or expired (out of date). Follow FDA guidelines on how to safely dispose of unused medicine.
  • Keep cobicistat and all medicines out of reach of children.
Where can I find more information about cobicistat?Where can I find more information about cobicistat?

Where can I find more information about cobicistat?

Manufacturer Information

Gilead Sciences, Inc.
Main number: 800-445-3235
Patient assistance: 800-226-2056

 

Last Reviewed: June 1, 2021