Clear Search sequence regions
Bookmark Forward

QuickView for Fosamprenavir (compound)


PubChem
Name: fosamprenavir
PubChem Compound ID: 11954282
Molecular formula: C25H36CaN3O10PS
Molecular weight: 641.685 g/mol
Synonyms:
Lexiva; Fosamprenavir calcium hydrate; Fosamprenavir calcium hydrate (JAN); D02867; Lexiva (TN)
DrugBank
Identification
Name: fosamprenavir
Name (isomeric): DB01319
Drug Type: small molecule
Brand: Lexiva, Telzir
Category: Prodrugs, HIV Protease Inhibitors, Anti-HIV Agents
CAS number: 226700-79-4
Pharmacology
Indication: Indicated in combination with other antiretroviral agents for the treatment of human immunodeficiency virus (HIV-1) infection, as well as postexposure prophylaxis of HIV infection in individuals who have had occupational or nonoccupational exposure to potentially infectious body fluids of a person known to be infected with HIV when that exposure represents a substantial risk for HIV transmission. The use of fosamprenavir is pending revision due to a potential association between the drug and myocardial infarction and dyslipidemia in HIV infected adults.
Pharmacology:
Fosamprenavir is a pro-drug of the protease inhibitor and antiretroviral drug amprenavir. It has little or no antiviral activity until it is hydrolyzed by cellular phosphatases into amprenavir, which is the active ingredient. That metabolization increases the duration that amprenavir is available, making fosamprenavir a slow-release version of ampr...
show more »
Mechanism of Action:
Fosamprenavir is a prodrug that is rapidly hydrolyzed to amprenavir by cellular phosphatases in the gut epithelium as it is absorbed. Amprenavir is an inhibitor of HIV-1 protease. During HIV replication, HIV protease cleaves viral polypeptide products of the Gag and Gag-Pol genes to form structural proteins of the virion core and essential viral en...
show more »
Absorption: The absolute oral bioavailability of amprenavir after administration of fosamprenavir in humans has not been established. After administration of a single 1,400 mg dose in the fasted state, fosamprenavir oral suspension (50 mg/mL) and fosamprenavir tablets (700 mg) provided similar amprenavir exposures (AUC), however, the Cmax of amprenavir after administration of the suspension formulation was 14.5 % higher compared with the tablet.
Protein binding: Very high (approximately 90%); primarily bound to alpha 1 -acid glycoprotein. Higher amounts of unbound amprenavir present as amprenavir serum concentrations increase.
Biotransformation: In the gut epithelium during absorption, fosamprenavir is rapidly and almost completely hydrolyzed to amprenavir and inorganic phosphate prior to reaching the systemic circulation. Amprenavir is metabolized in the liver by the cytochrome P450 3A4 (CYP3A4) enzyme system.
Route of elimination: Excretion of unchanged amprenavir in urine and feces is minimal. The renal elimination of unchanged amprenavir represents approximately 1% of the administered dose; therefore, renal impairment is not expected to significantly impact the elimination of amprenavir. Amprenavir, the active metabolite of fosamprenavir, is metabolized in the liver by the cytochrome P450 enzyme system.
Half Life: The plasma elimination half-life of amprenavir (the active metabolite) is approximately 7.7 hours.
Affected organisms: Human Immunodeficiency Virus
Interactions
Food interaction:
Vitamin E increases fosamprenavir bioavailability.
Take with or without food, however avoid lipid-rich meals.
Avoid alcohol, especially with the oral solution since it contains propylene glycol which competes with alcohol for alcohol dehydrogenase metabolism.
Drug interaction:
DantroleneFosamprenavir may increase the serum concentration of dantrolene by decreasing its metabolism. Consider alternate therapy or monitor for changes in the therapeutic and adverse effects of dantrolene if fosamprenavir is initiated, discontinued or dose changed.
TrimipramineThe strong CYP3A4 inhibitor, Fosamprenavir, may decrease the metabolism and clearance of Trimipramine, a CYP3A4 substrate. Consider alternate therapy or monitor for changes in therapeutic and adverse effects of Trimipramine if Fosamprenavir is initiated, discontinued or dose changed.
SildenafilThe protease inhibitor, fosamprenavir, may increase the effect and toxicity of sildenafil.
St. John's WortSt. John's Wort decreases the effect of indinavir
TemsirolimusFosamprenavir may inhibit the metabolism and clearance of Temsirolimus. Concomitant therapy should be avoided.
show more »

Targets


Enzymes