ENFUVIRTIDE
| ENFUVIRTIDE (en-fu-vir'tide) Fuzeon Classifications: antiviral; antiretroviral; fusion inhibitor; Therapeutic: antiretroviral; fusion inhibitor Pregnancy Category: B |
Availability
90 mg/mL injection
Action
Enfuvirtide interferes with entry of HIV-1 into host cells by inhibiting fusion of the virus with the host cell membranes. In order for HIV-1 to enter and infect a human cell, the viral surface glycoprotein (gp41) must bind to the host CD4+ cells. Then, the viral glycoprotein undergoes a change in shape facilitating the fusion of viral membranes with the host cell membrane. Enfuvirtide binds to viral envelope glycoprotein (gp41) and prevents the change in shape required for membrane fusion and viral entry into target cells.
Therapeutic Effect
Prevents entry of the HIV-1 virus into host cells.
Uses
Treatment of advanced HIV disease with evidence of resistance to other therapies.
Contraindications
Hypersensitivity to enfuvirtide or any of its components; lactation.
Cautious Use
Renal and hepatic impairment; renal clearance of <35 mL/min; bacterial pneumonia, low initial CD4 count, past history of lung disease, high initial viral load, IV drug use; mannitol hypersensitivity; history of pulmonary disease; pregnancy (category B).
Route & Dosage
| Advanced HIV Disease Adult/Adolescent (≥16 y or ≥42.6 kg): SC 90 mg b.i.d. Child/Adolescent (6–16 y or <42.6 kg): SC 2 mg/kg (up to 90 mg) b.i.d. |
Administration
Subcutaneous- Reconstitute by adding 1.1 mL sterile water for injection into vial. Mix by gently tapping vial for 10 sec, then gently rolling in palms of hands. Ensure that no drug is remaining on vial wall. Allow vial to stand until powder completely dissolves (up to 45 min). Solution should be clear, colorless, and without bubbles or particulate matter.
- Bring refrigerated reconstituted solution to room temperature before injection. Ensure that powder is fully dissolved and solution is clear, colorless, and without bubbles or particulate matter.
- Inject into upper arm, abdomen, or anterior thigh.
- Rotate injection sites and inject in an area with no current injection site reaction.
- Store unreconstituted vials at 15°–30° C (59°–86° F) or refrigerated at 2°–6° C (3°–46° F); do not freeze.
Adverse Effects (≥1%)
Body as a Whole: Injection site reactions (pain, induration, erythema, nodules, cysts, pruritus, ecchymoses), infection at injection site, fatigue, systemic hypersensitivity reactions, Guillain-Barr? syndrome, asthenia, herpes simplex infections, influenza, lymphadenopathy, myalgia, peripheral neuropathy. CNS: Anxiety, depression, insomnia. GI: Diarrhea, nausea, abdominal pain, anorexia, constipation, dysgeusia, pancreatitis, weight loss. Hematologic: Eosinophilia, anemia. Metabolic: Increased amylase, increased lipase, increased ALT and AST, hypertriglyceridemia. Respiratory: Bacterial pneumonia, acute respiratory distress syndrome, cough, sinusitis. Skin: Pruritus, skin papilloma. Special Senses: Conjunctivitis. Urogenital: Glomerulonephritis.Interactions
None yet reported.Pharmacokinetics
Absorption: 84.3% absorbed from SC site. Peak: Average 4–8 h. Distribution: 92% protein bound. Metabolism: Catabolized into constituent amino acids. Half-Life: 4 h.Nursing Implications
Assessment & Drug Effects
- Inspect SC sites for S&S of site reactions (e.g., itching, swelling, redness, pain, tenderness, or hardened skin) that usually last for <7 d postinjection.
- Monitor closely for S&S of pneumonia, especially with low initial CD4 count, high initial viral load, IV drug use, smoking, or prior history of lung disease.
- Lab tests: Periodic LFTs, serum lipase and amylase, lipid profile, and CBC with differential.
Patient & Family Education
- Report promptly S&S of infection at SC injection sites: increased heat, redness, pain, or oozing.
- Report promptly S&S of pneumonia: cough with fever, rapid breathing, shortness of breath.
Common adverse effects in italic, life-threatening effects underlined; generic names in bold; classifications in SMALL CAPS; 
Canadian drug name; 
Prototype drug