Drug information of Amprenavir
Amprenavir inhibits HIV-1 protease by binding to the enzyme's active site. This prevents the processing of viral gag and gag-pol polyprotein precursors and results in the formation of immature noninfectious viral particles.
Mechanism of effect
Amprenavir is a protease inhibitor with activity against Human Immunodeficiency Virus Type 1 (HIV-1). Protease inhibitors block the part of HIV called protease. HIV-1 protease is an enzyme required for the proteolytic cleavage of the viral polyprotein precursors into the individual functional proteins found in infectious HIV-1.Amprenavir binds to the protease active site and inhibits the activity of the enzyme. This inhibition prevents cleavage of the viral polyproteins resulting in the formation of immature non-infectious viral particles. Protease inhibitors are almost always used in combination with at least two other anti-HIV drugs.
Rapidly absorbed after oral administration in HIV-1-infected patients.
time to peak concentration (Tmax): 1-2 hours after a single oral dose.
Half-life: 7.1-10.6 hours
Agenerase: Capsule 50mg
Agenerase: Capsule 150mg
Agenerase: Suspension 15mg
- HIV infection: 1200 mg ORALLY twice a day
- HIV infection: When used with ritonavir 200 mg once daily, amprenavir 1200 mg ORALLY once daily
- HIV infection: When used with ritonavir 100 mg twice daily, amprenavir 600 mg ORALLY twice daily
- renal impairment: oral solution CONTRAINDICATED in patients with renal failure due to propylene glycol content; use with caution in patients with renal impairment
- hepatic failure: oral solution CONTRAINDICATED in patients with hepatic failure
- hepatic impairment: Child-Pugh score 5-8; 450 mg twice daily (capsules), 513 mg twice daily (solution); Child-Pugh score 9-12; 300 mg twice daily (capsules), 342 mg twice daily (solution)
- HIV infection: capsules; 13 to 16 years, 1200 mg ORALLY twice daily
- HIV infection: capsules; 4 to 16 years and less than 50 kg, 20 mg/kg ORALLY twice daily or 15 mg/kg 3 times a day; maximum 2400 mg/day
- HIV infection: solution; 4 to 16 years and less than 50 kg, 22.5 mg/kg ORALLY twice daily or 17 mg/kg 3 times a day; maximum 2800 mg/day)
- HIV infection: solution; 13 years and older and 50 kg or more, 1400 mg ORALLY twice daily
- HIV infection: Adult: yes
- HIV infection: Pediatric: yes (4 years and older)
Drug contraindicationsliver failure , renal failure , Pregnancy , Children under4 years , Hypersensitivity to this drug or components
Side effectsDiarrhea , Headache , nausea , vomiting , urticaria , Stevens-Johnson syndrome , Cutaneous Reaction , Abdominal pain , Abdominal discomfort
InteractionsPimozide , Dihydroergotamine , Cisapride , Methylergonovin , ergotamine , ergonovine , Midazolam , Colchicine , propoxyphene , nasal Mometasone , Maraviroc , Halofantrine , Delavirdine , Terfenadine , Fesoterodine , Alfuzosin , Erdafitinib , trabectedine , Triazolam
- alcohol use; may compete for the same metabolic pathway of elimination as the excipient, propylene glycol (solution only)
- amprenavir solution should only be used when the capsules or other protease inhibitor formulations are not therapeutic options
- anticoagulant therapy; amprenavir provides high daily doses of vitamin E that may exacerbate blood coagulation defect of vitamin K deficiency caused by anticoagulant therapy
- Diabetes mellitus; potential for exacerbation, new onset, or hyperglycemia may occur
- Ethnic populations (Asians, Eskimos, Native Americans); may be at increased risk for propylene glycol toxicity (solution only)
- Hemolytic anemia, acute has been reported
- Hepatic impairment ; amprenavir is principally metabolized in the liver
- Hypertriglyceridemia may occur
- Malabsorption; amprenavir provides high daily doses of vitamin E that may exacerbate blood coagulation defect of vitamin K deficiency caused by malabsorption
- Opportunistic infections, indolent or residual; inflammatory response (immune reconstitution syndrome) may occur
- Sulfonamide allergy; amprenavir is a sulfonamide
- Stevens-Johnson syndrome and other severe and life-threatening skin reactions have occurred
- Women; may be at increased risk for propylene glycol toxicity (solution only)
Points of recommendation
- Advise patient to practice safe sex. Drug does not prevent HIV transmission.
- Instruct patient to report signs/symptoms of increased bleeding, anemia, hepatotoxicity, or nephrotoxicity.
- Patient may take with or without food, but should avoid high-fat meals.
- Patient should take 1 h before or after antacids or buffered didanosine.
- Instruct patient to avoid alcohol, supplemental vitamin E, and St. John's Wort.
- Advise patient there are multiple significant drug-drug interactions for this drug. Consult healthcare professional prior to new drug use (including over-the-counter and herbal drugs).