Title: Enfuvirtide
CAS Registry Number: 159519-65-0
Additional Names: Pentafuside
Manufacturers' Codes: DP-178; T-20
Trademarks: Fuzeon (Roche)
Molecular Formula: C204H301N51O64
Molecular Weight: 4491.88
Percent Composition: C 54.55%, H 6.75%, N 15.90%, O 22.80%
Literature References: HIV fusion inhibitor. Synthetic, 36 amino acid peptide corresponding to a region of gp41, the transmembrane subunit of the HIV-1 envelope protein. Prepn and biological activity: D. P. Bolognesi et al., WO 9428920; eidem, US 5464933 (1994, 1995 both to Duke Univ.); C. T. Wild et al., Proc. Natl. Acad. Sci. USA 91, 9770 (1994). Mechanism of action study: R. A. Furuta et al., Nat. Struct. Biol. 5, 276 (1998). Clinical pharmacokinetics: J. M. Kilby et al., AIDS Res. Hum. Retroviruses 18, 685 (2002). Review of development: N. Press et al., Curr. Opin. Anti-Infect. Invest. Drugs 1, 171-178 (1999); of clinical evaluations: A. Pozniak, J. HIV Ther. 6, 91-94 (2001).
Therap-Cat: Antiviral.
Keywords: HIV Fusion Inhibitor; Antiviral.
Enilconazole Eniluracil Enniatins Enocitabine Enoxacin

Clinical data
Trade names Fuzeon
AHFS/Drugs.com monograph
Pregnancy cat. B2 (AU) B (US)
Legal status Prescription Only (S4) (AU) -only (CA) POM (UK) -only (US) S4
Routes Subcutaneous (SC)
Pharmacokinetic data
Bioavailability 84.3% (SC)
Protein binding 92%
Metabolism Hepatic
Half-life 3.8 hours
Excretion unknown
CAS number 159519-65-0 YesY
ATC code J05AX07
PubChem CID 16130199
DrugBank DB00109
ChemSpider 16743716 YesY
KEGG D02499 N
ChEBI CHEBI:608828 N
NIAID ChemDB 059486
Chemical data
Formula C202H298N50O64 
Mol. mass 4492.1 g/mol
 N (what is this?)  (verify)

Enfuvirtide (INN) is an HIV fusion inhibitor, the first of a novel class of antiretroviral drugs used in combination therapy for the treatment of HIV-1 infection. It is marketed under the trade name Fuzeon (Roche).

Enfuvirtide therapy costs an estimated US$25,000 per year in the United States. Its cost and inconvenient dosing regimen are factors behind its use as a reserve, for salvage therapy in patients with multi-drug resistant HIV.