Enfuvirtide (or T-20) belongs to class of drugs called fusion inhibitors, so called because they stop HIV from binding to and entering the CD4 cell.  HIV needs to attach to the CD4 cell, firstly by attaching to a receptor, then to a specialised protein call glycoprotein 41 (gp41) on the surface of the CD4 cell.  T-20 binds to gp41, preventing HIV from attaching or entering the CD4 cell.

Enfuvirtide has to be injected under the skin (subcutaneous) twice daily.  Many people develop skin reactions where it is injected, and most are minor.

Enfuvirtide is designed for people who have developed multiple drug resistance.  It has not been studied in people who have not taken HIV treatment (treatment naive). 

Basic info

Generic name enfuvirtide
Brand name Fuzeon
Also known as T-20
Drug class Entry Inhibitors
Pediatric dosing? Available in doses suitable for children and/or young people.
Availability in Australia Available on a restricted authority basis the Pharmaceutical Benefits Scheme (PBS) through S100 prescribers since 2004
This drug may be available through clinical trials in Australia.
You may be able to import this drug from overseas for your personal use.
Formulation 90 mg vial

Taking it

Like most anti-HIV drugs, enfuvirtide must be taken in combination with other drugs to be completely effective. Commonly, enfuvirtide is combined with one other nucleoside (NRTI) drug and either a protease inhibitor or non-nucleoside, although other combinations are sometimes used. Your doctor will advise you on the right combination of drugs to suit your circumstances.


One 90 mg vial by subcutaneous injection twice a day.

Regardless of what you read on this website or elsewhere, you should always take your medications according to your doctor's instructions. If you're unsure, speak to your doctor or pharmacist.

With or without food

enfuvirtide may be taken with or without food

Side effect

All drugs can produce side effects in some people. These may be mild, moderate or severe, so you should be aware of potential side effects before starting any drug, and speak to your doctor if you experience side effects that concern you.

  • Common side effects may include injection site reactions.
  • It's unlikely you will experience all of these side effects, and you may not experience any side effects at all. Before starting any new drug, ask your doctor about side effects you might experience and discuss strategies for dealing with side effects if they do occur. If you experience any significant side effect you should continue taking your medicine and see your doctor as soon as possible.

Interactions with other drugs

There are no known clinically significant interactions between enfuvirtide and any other medications.

Related Content

  • Consumer Medicine Information (CMI)
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