Fosamprenavir (FPV), sold under the brand names Lexiva and Telzir, is a

medication Medication (also called medicament, medicine, pharmaceutical drug, medicinal product, medicinal drug or simply drug) is a drug used to medical diagnosis, diagnose, cure, treat, or preventive medicine, prevent disease. Drug therapy (pharmaco ...

used to treat

HIV/AIDS The HIV, human immunodeficiency virus (HIV) is a retrovirus that attacks the immune system. Without treatment, it can lead to a spectrum of conditions including acquired immunodeficiency syndrome (AIDS). It is a Preventive healthcare, pr ...

. It is a

prodrug A prodrug is a pharmacologically inactive medication or compound that, after intake, is metabolized (i.e., converted within the body) into a pharmacologically active drug. Instead of administering a drug directly, a corresponding prodrug can be ...

of the protease inhibitor and

antiretroviral drug The management of HIV/AIDS normally includes the use of multiple Antiviral drug, antiretroviral drugs as a strategy to control HIV/AIDS, HIV infection. There are several classes of antiretroviral agents that act on different stages of the HIV li ...

amprenavir. It is marketed by

ViiV Healthcare ViiV Healthcare ( ) is a British multinational pharmaceutical company specializing in the research and development of medicines to treat and prevent HIV/AIDS. Its global headquarters is located in London. The company was created as a joint ...

as the

calcium Calcium is a chemical element; it has symbol Ca and atomic number 20. As an alkaline earth metal, calcium is a reactive metal that forms a dark oxide-nitride layer when exposed to air. Its physical and chemical properties are most similar to it ...

salt. Fosamprenavir was approved for medical use in the United States in October 2003, and in the European Union in July 2004. The human body metabolizes fosamprenavir in order to form amprenavir, which is the active ingredient. A head-to-head study with lopinavir showed the two drugs to have comparable potency, but patients on fosamprenavir tended to have a higher serum cholesterol.

Medical uses

Fosamprenavir is used for the treatment of

HIV-1 The subtypes of HIV include two main subtypes, known as HIV type 1 (HIV-1) and HIV type 2 (HIV-2). These subtypes have distinct genetic differences and are associated with different epidemiological patterns and clinical characteristics. HIV-1 e ...

infections, typically but not necessarily in combination with low-dose

ritonavir Ritonavir, sold under the brand name Norvir, is an antiretroviral medication used along with other medications to treat HIV/AIDS. This combination treatment is known as highly active antiretroviral therapy (HAART). Ritonavir is a protease inhi ...

or other antiviral drugs.

Adverse effects

The most common adverse effect is diarrhea. Other common side effects include

headache A headache, also known as cephalalgia, is the symptom of pain in the face, head, or neck. It can occur as a migraine, tension-type headache, or cluster headache. There is an increased risk of Depression (mood), depression in those with severe ...

, dizziness and exanthema, which is usually transient. Severe allergic reactions (

Stevens–Johnson syndrome Stevens–Johnson syndrome (SJS) is a type of severe skin reaction. Together with toxic epidermal necrolysis (TEN) and #Classification, Stevens–Johnson/toxic epidermal necrolysis (SJS/TEN) overlap, they are considered febrile mucocutaneous d ...

) are rare.

Interactions

Amprenavir (the active metabolite of fosamrenavir, which is found in blood plasma, liver and other organs) is metabolized via the liver enzyme

CYP3A4 Cytochrome P450 3A4 (abbreviated CYP3A4) () is an important enzyme in the body, mainly found in the liver and in the intestine, which in humans is encoded by ''CYP3A4'' gene. It organic redox reaction, oxidizes small foreign organic molecules ( ...

and also weakly inhibits this enzyme. This means that combination with drugs that are also metabolized by CYP3A4 can increase their plasma concentrations and thus side effects; and combination with drugs that inhibit CYP3A4 can increase amprenavir concentrations. When combining fosamprenavir with low doses of the CYP3A4 inhibitor ritonavir, this interaction is intended as it allows for application of lower fosamprenavir doses.

Pharmacology

Fosamprenavir is quickly activated to amprenavir, even before it reaches the circulation. Amprenavir is a HIV protease inhibitor. 3nu3 478

References

External links

* * {{Portal bar , Medicine , Viruses Carbamates CYP3A4 inhibitors Drugs developed by GSK plc HIV protease inhibitors Prodrugs Sulfonamides Tetrahydrofurans