Dosing and uses of Fuzeon (enfuvirtide)
Adult dosage forms and strengths
powder for injection
- 90mg/vial
HIV Infection
90 mg SC q12hr
Administration
Inject SC into the upper arm, anterior thigh, or abdomen
Pediatric dosage forms and strengths
powder for injection
- 90mg/vial
HIV Infection
<6 years old: Safety and efficacy not established
6-16 years: 2 mg/kg SC q12hr; not to exceed 90 mg q12hr
>16 years: As adults; 90 mg SC q12hr
Administration
Inject SC into the upper arm, anterior thigh, or abdomen
Fuzeon (enfuvirtide) adverse (side) effects
>10%
Difficult to separate from background regimen
Multiple inj site rxn (98%)
Pain & discomfort (96%)
Erythema (91%)
Induration (90%)
Nodules and cysts (80%)
Pruritis (65%)
Ecchymosis (52%)
Diarrhea (31%)
Nausea (22%)
Fatigue (20%)
Periph. neuropathy
Insomnia
1-10%
Difficult to separate from background regimen
Asthenia
Depression
Pruritis
Abdominal pain
Anorexia
Decreased appetite
Weight loss
Myalgia
Cough
Herpes simplex
Influenza-like illness
Pneumonia
Sinusitis
Lymphadenopathy
Pancreatitis
<1% (selected)
Unstable angina
Toxic hepatitis
Renal failure
Respiratory distress
Guillain-Barre syndrome
Hypersensitivity rxn
Primary immune complex reaction
Suicide attempt
Postmarketing Reports
Cutaneous amyloidosis at the injection site
Warnings
Contraindications
Hypersensitivity
Cautions
Use only in combination with other antiretrovirals
Each injection should be in a different site than the previous one (upper arm, anterior thigh, abdomen)
Monitor for signs and symptoms of pneumonia
Low initial CD4+ T-cell count and high initial viral load
Pulmonary disease, smoking
If pt becomes pregnant, call Antiretroviral Pregnancy Registry 1-800-258-4263
The possibility exists that this drug could result in a false-positive HIV test using (ELISA); use of a confirmatory test (Western blot) is advised
Risk of immune reconstitution syndrome if used in combination with other antiretroviral drugs; patients may develop an inflammatory response to indolent or residual opportunistic infection
Pregnancy and lactation
Pregnancy category: B
Lactation: Unknown whether enfuvirtide is excreted in milk; avoid in breastfeeding women; the CDC advises HIV-infected women not to breast-feed to avoid postnatal transmission of HIV
Pregnancy categories
A: Generally acceptable. Controlled studies in pregnant women show no evidence of fetal risk.
B: May be acceptable. Either animal studies show no risk but human studies not available or animal studies showed minor risks and human studies done and showed no risk.
C: Use with caution if benefits outweigh risks. Animal studies show risk and human studies not available or neither animal nor human studies done.
D: Use in LIFE-THREATENING emergencies when no safer drug available. Positive evidence of human fetal risk.
X: Do not use in pregnancy. Risks involved outweigh potential benefits. Safer alternatives exist.
NA: Information not available.
Pharmacology of Fuzeon (enfuvirtide)
Mechanism of action
Synthetic peptide; inhibits fusion of HIV-1 with CD4+ cell membrane
Combination use recommended
Pharmacokinetics
Half-Life: 3.8 hr
Peak Plasma Time: 4-8 hr
Peak Plasma Concentration: 4.59 +/- 1.5 mcg/mL
AUC: 55.8 +/- 12.1 mcg.hr/mL
Bioavailability: 84%
Vd: 5.5L
Protein Bound: 92%
Metabolism: Hydrolysis
Total Body Clearance: 21-29 mL/hr/kg
