FUZEON blocks HIV outside CD4+ T cells—before the virus can enter and infect healthy cells.


FUZEON is designed to target HIV outside the CD4 Cells

  • FUZEON is always used with other anti-HIV medicines to treat adults and children ages 6 years and older with HIV infection.
  • Because of the way that FUZEON may work, FUZEON may be active against HIV that is resistant to other HIV medicines. So if you haven't been on FUZEON before and those other medicines have failed you, your virus may be sensitive to FUZEON. As with other HIV medicines, it is possible to develop resistance to FUZEON.



If you have a detectable viral load and have experienced treatment failure with previous drug regimens, FUZEON may be an option for you.

It may be time to talk to your healthcare provider about FUZEON if you have only 1 fully active agent in your current regimen.

To design a new regimen, your treatment history—as well as past and current resistance test results—should be used to identify at least 2 (preferably 3) fully active agents to combine with an optimized background antiretroviral (ARV) regimen (AI). A fully active agent is one that is likely to have ARV activity on the basis of your treatment history, drug-resistance testing, and/or a novel mechanism of action.1

Do not use FUZEON if you are allergic to any of the ingredients in FUZEON.


1. Department of Health and Human Services. Panel on Antiretroviral Guidelines for Adults and Adolescents. Guidelines for the Use of antiretroviral agents in HIV-1-infected adults and adolescents. Accessed December 21, 2019.


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What is FUZEON?

FUZEON is a medicine called an HIV (human immunodeficiency virus) fusion inhibitor. FUZEON is always used with other anti-HIV medicines to treat adults and children ages 6 years and older with HIV infection.

FUZEON blocks HIV’s ability to infect healthy CD4 cells. When used with other anti-HIV medicines, FUZEON can reduce the amount of HIV in the blood and increase the number of CD4 cells. This may keep your immune system healthy, so it can help fight infection.

Who should not use FUZEON?

Do not use FUZEON if you are allergic to any of the ingredients in FUZEON.

What are the possible side effects of FUZEON?

Injection Site Reactions (ISRs)

FUZEON causes injection site reactions. Almost all people get injection site reactions with FUZEON. Reactions are usually mild to moderate but occasionally may be severe. Reactions on the skin where FUZEON is injected include:

  • itching
  • swelling
  • redness
  • pain or tenderness
  • hardened skin
  • bumps

These reactions generally happen within the first week of FUZEON treatment and usually happen again as you keep using FUZEON. A reaction at one skin injection site usually lasts for less than 7 days. Injection site reactions may be worse when injections are given again in the same place on the body or when the injection is given deeper than it should be (for example, into the muscle).

If you are worried about the reaction you are having, call your healthcare provider to help you decide if you need medical care. If the injection site reaction you are having is severe, call your healthcare provider right away. If you have an injection site reaction, you can discuss with your healthcare provider ways to help the symptoms.

An injection site can get infected. It is important to follow the FUZEON Injection Instructions that come with your medicine to lower your chances of getting an injection site infection.

Call your healthcare provider right away if there are signs of infection at the injection site such as oozing, increasing heat, swelling, redness or pain.

Injection using Biojector® 2000
Shooting nerve pain and tingling lasting up to 6 months from injecting close to large nerves or near joints, and bruising and/or collections of blood under the skin have been reported with use of the Biojector 2000 needle-free device to inject FUZEON. If you are taking any blood thinners, or have hemophilia or any other bleeding disorder, you may be at higher risk of bruising or bleeding after using the Biojector.

Patients with HIV get bacterial pneumonia more often than patients without HIV. Patients taking FUZEON with other HIV medicines may get bacterial pneumonia more often than patients not receiving FUZEON. It is unclear if this is related to the use of FUZEON. You should contact your healthcare provider right away if you have a cough, fever or trouble breathing. Patients are more likely to get bacterial pneumonia if they had a low number of CD4 cells, increased amount of HIV in the blood, intravenous (injected into the vein) drug use, smoking or had experienced lung disease in the past. It is unclear if pneumonia is related to FUZEON.

Allergic reactions 
FUZEON can cause serious allergic reactions. Symptoms of a serious allergic reaction with FUZEON can include:

  • trouble breathing
  • fever with vomiting and a skin rash
  • blood in your urine
  • swelling of your feet

Call your healthcare provider right away if you get any of these symptoms. Discuss with your healthcare provider if you have previously taken FUZEON and experienced any of these reactions.

Other Side Effects
The following side effects were seen more often in patients using FUZEON with their other anti-HIV medicines than in patients not using FUZEON with their other anti-HIV medicines:

  • pain and numbness in feet or legs
  • loss of sleep
  • depression
  • decreased appetite
  • sinus problems
  • enlarged lymph nodes
  • weight decrease
  • weakness or loss of strength
  • muscle pain
  • constipation
  • pancreas problems

These are not all possible side effects of FUZEON. For more information, ask your healthcare provider or pharmacist. If you have questions about side effects, ask your healthcare provider.

As with other anti-HIV medicines, FUZEON may strengthen the body’s immune response which could uncover hidden infections. Report any new or continuing symptoms to your healthcare provider. Your healthcare provider will tell you what to do and may be able to help you with these side effects.

FUZEON is not a cure for HIV infection or AIDS; FUZEON does not prevent the transmission of HIV. For complete details on FUZEON, please see the Patient Information, or call 1-877-4-FUZEON (1-877-438-9366).