Enfuvirtide

Enfuvirtide is a prescription medication used to treat human immunodeficiency virus (HIV). It is always used in combination with other medications. Enfuvirtide belongs to a group of drugs called HIV fusion inhibitors. It works by stopping HIV from entering human cells. HIV must enter human cells in order to replicate.

This medication comes in an injectable form. It is injected just under the skin of the upper arm, stomach area, or thigh, twice daily.

Common side effects of enfuvirtide include redness, pain, and other effects at the injection site. Other common side effects include weight loss, sinus infection and dizziness. Do not drive a car or operate machinery until you know how this medication affects you.

Enfuvirtide is a prescription medication used to treat human immunodeficiency virus (HIV). It is always used in combination with other medications.

This medication may be prescribed for other uses. Ask your doctor or pharmacist for more information.

Take this medication exactly as prescribed by your doctor. Follow the directions on your prescription label carefully.

The dose your doctor recommends may be based on the following:

• your weight
• your age

The recommended dose of enfuvirtide is 90 mg (1 mL) twice daily.

The recommended dose of enfuvirtide for pediatric patients (6 to 16 years of age) is 2 mg/kg to a maximum dose of 90 mg twice daily.

• Do not use enfuvirtide if you are allergic to any of the ingredients in it.
• Avoid doing anything that can spread HIV infection since enfuvirtide does not stop you from passing the HIV infection to others.
  • Do not share needles or other injection equipment.
  • Do not share personal items that can have blood or body fluids on them, like toothbrushes or razor blades.
  • Do not have any kind of sex without protection. Always practice safer sex by using a latex or polyurethane condom or other barrier method to reduce the chance of sexual contact with semen, vaginal secretions or blood.
• Do not drive or operate heavy machinery if enfuvirtide makes you feel dizzy.

Injection Site Reactions

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

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

These reactions generally happen within the first week of enfuvirtide treatment and usually happen again as you keep using enfuvirtide. 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 enfuvirtide 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 enfuvirtide. 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.

Pneumonia

Patients with HIV get bacterial pneumonia more often than patients without HIV. Patients taking enfuvirtide with other HIV medicines may get bacterial pneumonia more often than patients not receiving enfuvirtide. It is unclear if this is related to the use of enfuvirtide. 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 enfuvirtide.

Allergic reactions

Enfuvirtide can cause serious allergic reactions. Symptoms of a serious allergic reaction with enfuvirtide 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.

Other side effects

The following side effects were seen more often in patients using enfuvirtide with their other anti-HIV medicines than in patients not using enfuvirtide 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 the side effects of enfuvirtide. For more information, ask your healthcare provider or pharmacist.

If you have questions about side effects, ask your healthcare provider. 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.

Tell your healthcare provider about all the medicines you use, including prescription and non-prescription medicines, vitamins, and herbal supplements. Enfuvirtide has not been tested with all medicines. 

Enfuvirtide does not affect other anti-HIV medicines or the medicine rifampin (also known as rifampicin, Rifadin or Rimactane). You can take enfuvirtide at the same times or at different times than your other anti-HIV medicines.

Tell your healthcare provder if you are pregnant or plan to become pregnant.

The FDA categorizes medications based on safety for use during pregnancy. Five categories - A, B, C, D, and X, are used to classify the possible risks to an unborn baby when a medication is taken during pregnancy.

Enfuvirtide falls into category B. There are no well-done studies that have been done in humans with but in animal studies, pregnant animals were given this medication, and the babies did not show any medical issues related to this medication.

Pregnancy Registry. There is a pregnancy registry for women who take antiviral medicines during pregnancy. The purpose of this registry is to collect information about the health of you and your baby. Talk with your healthcare provider about how you can take part in this registry.

Tell your healthcare provider if you are breastfeeding. 

It is not known if enfuvirtide can be passed to your baby in your breast milk and whether it could harm your baby. Also, mothers with HIV-1 should not breastfeed because HIV-1 can be passed to the baby in the breast milk.

Avoid doing anything that can spread HIV infection since enfuvirtide does not stop you from passing the HIV infection to others.

Do not inject enfuvirtide in the same area as you did the time before.

You can use enfuvirtide whether you have eaten or not. Food does not affect enfuvirtide.

When your enfuvirtide supply runs low, be sure to have it refilled. This is very important because the amount of virus in your blood may increase if the medicine is stopped for even a short time. If you miss or skip doses of enfuvirtide, HIV may develop resistance to enfuvirtide and become harder to treat.