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Related to enfuvirtide: Maraviroc



Pharmacologic class: Human immunodeficiency-1 (HIV-1) fusion inhibitor

Therapeutic class: Antiretroviral

Pregnancy risk category B


Interferes with entry of HIV-1 into cells by inhibiting fusion of viral and cellular membranes


Powder for injection: 90 mg/1-ml vial

Indications and dosages

HIV-1 infection in adults in combination with other antiretrovirals

Adults: 90 mg subcutaneously b.i.d. in upper arm, anterior thigh, or abdomen

Children ages 6 to 16: 2 mg/kg subcutaneously b.i.d. in upper arm, anterior thigh, or abdomen. Maximum dosage is 90 mg b.i.d.


• Hypersensitivity to drug or its components


Use cautiously in:
• increased risk of pneumonia
• injection site reaction
• concurrent use of anticoagulants
• hemophilia or other coagulant disorders
• elderly patients
• children younger than age 6 (safety and efficacy not established).


• Rotate injection sites.
• Be aware that preferred injection sites are upper arm, anterior thigh, and abdomen.
• Reconstitute with 1.1 ml of sterile water for injection, and gently tap vial for 10 seconds. Then gently roll vial between hands or allow vial to stand until product dissolves completely (could take up to 45 minutes).
• Know that drug is usually given with other antiretrovirals.
• Use reconstituted solution immediately.

Adverse reactions

CNS: fatigue, asthenia, insomnia, depression, anxiety, peripheral neuropathy

EENT: conjunctivitis, sinusitis

GI: nausea, diarrhea, upper abdominal pain, dry mouth, anorexia, pancreatitis

Hematologic: lymphadenopathy

Musculoskeletal: limb pain, myalgia

Respiratory: cough, pneumonia

Skin: folliculitis

Other: taste disturbance, decreased appetite, weight loss, herpes simplex infection, injection site reactions (erythema, induration, nodules, cysts, mild to moderate pain, infection), flulike illness, hypersensitivity reactions


Drug-diagnostic tests.Alanine aminotransferase, amylase, aspartate aminotransferase, creatine kinase, eosinophils, gamma-glutamyltransferase, lipase, triglycerides: increased levels

Hemoglobin: decreased level

Patient monitoring

• Inspect injection sites frequently for adverse reactions.
• Monitor CBC with white cell differential, lipid panel, liver function test results, and gastric enzymes levels.
• Watch for hypersensitivity reactions.
• Monitor nutritional and hydration status in light of GI adverse effects and underlying disease.

Patient teaching

• Teach patient (or caregiver) how to reconstitute and self-administer drug, as appropriate.

Instruct patient not to change dosage or stop taking drug unless prescriber approves.

Tell patient to immediately report signs or symptoms of hypersensitivity reaction (such as rash, fever, nausea and vomiting, and chills).
• Teach patient how to recognize signs and symptoms of injection site reaction. Tell him to contact prescriber if these occur, especially if they last more than 7 days.
• Advise female patient to notify prescriber if she is pregnant or plans to become pregnant.
• Tell HIV-infected patient not to breastfeed.
• If patient misses a dose, instruct him to take it as soon as he remembers. However, if it's almost time for next dose, tell him to skip the missed dose and take next dose on schedule.
• As appropriate, review all other significant adverse reactions and interactions, especially those related to the tests mentioned above.


An antiretroviral drug of the fusion inhibitor class used in combination with other drugs to treat HIV infection.


an antiretroviral.
indications This drug is used in combination with other antiretrovirals to treat HIV-1 infection.
contraindication Known hypersensitivity to this drug prohibits its use.
adverse effects Adverse effects of this drug include anxiety, peripheral neuropathy, taste disturbance, insomnia, depression, abdominal pain, anorexia, constipation, pancreatitis, injection site reactions, influenza, cough, conjunctivitis, lymphadenopathy, myalgia, hyperglycemia, and pneumonia. Life-threatening side effects include glomerulonephritis, renal failure, Guillain-Barré syndrome, thrombocytopenia, and neutropenia.


The first of a new class of anti-HIV drugs. Enfuvirtide (Fuzeon) interferes with the mechanism by which the membranes of HIV and of the target T cell fuse together so as to allow insertion of the viral genome. The drug is currently unique in that it attacks the virus before the T cell is infected. It does so by binding to a region of the envelope and blocking the conformational change necessary for fusion. Unfortunately, the drug, which requires twice-daily injections, is extremely expensive. A brand name is Fuzeon.
References in periodicals archive ?
Enfuvirtide, the first fusion inhibitor to treat HIV infection.
Enfuvirtide, an HIV-1 fusion inhibitor for drug- resistant HIV infection in North and South America.
Concomitant use of an active boosted protease inhibitor with enfuvirtide in treatment-experienced, HIV-infected individuals: recent data and consensus recommendations.
For these individuals, other new drugs have offered hope, particularly with regimens that include the fusion inhibitor enfuvirtide, which is the first available agent in a novel class since the development of protease inhibitors.
For experienced patients, "This section has been updated to redefine the goal of antiretroviral therapy in the management of treatment-experienced patients with virologic failure and to review the role of more potent ritonavir-boosted protease inhibitors such as tipranavir with or without enfuvirtide in these patients.
Patients' background regimens were based on the results of resistance testing and include a fully-active ritonavir-boosted protease inhibitor, and a second agent that was permitted to be a nucleoside or nucleotide reverse transcriptase inhibitor, etravirine, maraviroc or enfuvirtide.
Enfuvirtide must be administered by injection, but despite the disadvantages associated with peptide-based therapy, it has gained FDA approval because of its efficacy in multiple-drug-resistant HIV-1 patients.
4% of patients taking tipranavir/r combined with first-time enfuvirtide use achieved an undetectable viral load of less than 50 copies/mL, p=0.
The FDA approves the first entry inhibitor enfuvirtide Fuzeon, T20).
They also had little or no enfuvirtide resistance because this drug is in a different class--fusion inhibitors--from all other approved antiretrovirals (so there is no cross resistance), and 88% of these volunteers had no prior exposure to enfuvirtide itself.
WASHINGTON -- The best strategy for using two of the newest anti-HIV drugs, tipranavir and enfuvirtide, may be to use them together because each appears to work better when coupled with at least one other active anti-retroviral drug, several experts recommended at the annual Interscience Conference on Antimicrobial Agents and Chemotherapy.
Patients' background regimens were based on the results of resistance testing and included a fully-active ritonavir-boosted PI, and a second investigator-selected agent that was permitted to be a nucleoside or nucleotide reverse transcriptase inhibitor (NRTI), etravirine, maraviroc or enfuvirtide.