Enfuvirtide
Aliases: Fuzeon · T-20
Last verified: 2026-09-23
The short version
A 36-aa peptide — the first HIV fusion inhibitor: blocks viral-cell fusion (gp41).
Identity & type
- Molecular type
- analog
- Origin
- A 36-aa peptide — the first HIV fusion inhibitor: blocks viral-cell fusion (gp41).
Mechanism of action
Binds the HR1 region of gp41 → prevents the conformational change needed for membrane fusion.
Dosing & routes
Official / clinical context
Approved drug — indications, dosing and warnings are defined by the official label. 90 mg SC twice daily.
Regulator-approved labeling and published study designs — never a recommendation.
Community-reported practice
90 mg SC twice daily. Fuzeon: in resistant HIV, an add-on that lowers viral load; injection-site reactions are the main burden — mostly historical today.
Unverified self-reports. Not medical advice. Not endorsement.
Expected effects (community)
Fuzeon: in resistant HIV, an add-on that lowers viral load; injection-site reactions are the main burden — mostly historical today.
Protocol — official vs community
Official / label
Fuzeon (HIV-1, treatment-experienced patients with resistance): 90 mg SC twice daily into the upper arm, anterior thigh, or abdomen, rotating sites.
Duration: Chronic while it remains a needed component of a suppressive regimen; it is always used as part of an optimized background combination.
The first fusion inhibitor — mechanistically elegant, practically burdensome: twice-daily injection with near-universal local reactions is why it is largely a drug of historical and salvage-treatment interest today.
Community (anecdotal)
Structured protocol data for this entry is coming.
Human evidence
Approved 2003 for multidrug-resistant HIV; rarely used today.
Preclinical evidence
The preclinical phase was completed and submitted to regulators as part of registration; pharmacology and toxicology details are part of the official label.
Known risks
- Pronounced injection-site reactions (nearly all), rare pneumonia.characterized
Teal: characterized in clinical/labeling contexts. Amber: theoretical or reported outside controlled settings.
Unknowns & evidence gaps
- Real-world data outside controlled trials