Fusion and Entry Inhibitors for HIV
Enfuvirtide is available only as an injection. It is taken 2 times each day: once in the morning and then again 12 hours later.
Maraviroc is also called a chemokine receptor 5 (CCR-5) inhibitor. It is available as a pill taken twice a day.
How It Works
When HIV invades your body, the virus attaches to the outside of a CD4+ cell (a type of white blood cell) where it joins (fuses) with the cell and then multiplies. Fusion and entry inhibitors prevent fusion between the virus and the cell from occurring and prevent the virus from entering the cell. So HIV is unable to infect the cell and multiply.
Why It Is Used
Enfuvirtide and maraviroc are used in combination with other antiretroviral medicines for the treatment of HIV to prevent the virus from spreading in the body and to reduce the amount of virus in your blood (viral load). Enfuvirtide and maraviroc may be effective for people who have taken other anti-HIV drugs without success.
The use of three or more antiretroviral medicines (highly active antiretroviral therapy, or HAART) is the usual treatment for HIV infection.
The combination of medicines used for HAART will depend on your health, other conditions you might have (such as hepatitis), and results of testing. Talk to your doctor about the best treatment plan for you.
You may also want to start HIV treatment if your sexual partner does not have HIV. Treatment of your HIV infection can help prevent the spread of HIV to your sexual partner.3
How Well It Works
Enfuvirtide Common side effects of enfuvirtide include skin itchiness, swelling, and pain at the site of the injection. Other side effects may include fatigue, numbness in feet or legs, dizziness, and insomnia.
Maraviroc Common side effects of maraviroc include a cough, fever, dizziness, headache, and nausea. Other side effects reported for maraviroc include an increased risk of some infections and also liver and heart problems.
See Drug Reference for a full list of side effects. (Drug Reference is not available in all systems.)
What To Think About
Maraviroc is effective only against certain strains of HIV. Before maraviroc treatment is considered, you need to be tested to see if maraviroc will work against the virus you are infected with. This is called a tropism test. You should not take maraviroc unless you have had this test and it shows that maraviroc will be effective against the type of virus you have.
Enfuvirtide and maraviroc are used in combination with other anti-HIV drugs.
The U.S. Food and Drug Administration (FDA) approved enfuvirtide and maraviroc for people who have already been taking other anti-HIV medicines. They are not intended for use by people who are just starting drug treatment for HIV infection.
Enfuvirtide and maraviroc should be used to treat a pregnant woman only if the potential benefit is greater than the risk to the unborn baby (fetus).
Enfuvirtide is approved for use in people with HIV who are at least 6 years old.
Enfuvirtide is available only as an injection. It is taken 2 times each day: once in the morning and then again 12 hours later. To prepare each dose, you will need to mix the powdered medicine and sterile water, both of which come with the injector.
HIV can become resistant to enfuvirtide, so your viral load and CD4+ cell counts will be closely monitored while you are taking this medicine.
Maraviroc is approved for use in people with HIV who are at least 16 years old.
eMedicineHealth Medical Reference from Healthwise
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