Tags: Tenofovir

Treatment of HIV / AIDS

The goal of antiretroviral therapy is to achieve the maximum suppression of HIV replication (HIV RNA level that is less than the lower limit of quantitation). Secondary goals include an increase in CD4 lymphocytes and an improved quality of life. The ultimate goal is decreased morbidity and mortality.

Antiretroviral Agents General Statement

Decisions regarding when to initiate or modify antiretroviral therapy should be guided by monitoring plasma HIV-1 RNA levels (viral load), CD4+ T-cell counts, and the clinical condition of the patient. Although various other surrogate markers and laboratory parameters were used in the past to assess the risk of progression of HIV infection and evaluate efficacy of antiretroviral agents.

Patient Compliance and Issues Related to Dosage and Administration

Patient compliance with recommended regimens (even when asymptomatic) is essential to the potential benefits of antiretroviral therapy. Adherence to antiretroviral regimens is an important determinant of both the degree and duration of virologic suppression. Excellent adherence has been shown to increase the likelihood of sustained virologic control, which is important for reducing HIV-associated morbidity and mortality. Poor adherence has been shown to increase the likelihood of virologic failure and can lead to the development of resistance and limit the effectiveness of antiretroviral therapy.

Nucleoside Reverse Transcriptase Inhibitors

Safety and efficacy of zidovudine in pregnant women have been established and the drug appears to be well tolerated during pregnancy. In addition to zidovudine, data are available from clinical trials in pregnant women for didanosine, lamivudine, and stavudine; data regarding use of abacavir or tenofovir disoproxil fumarate (a nucleotide reverse transcriptase inhibitor) are not available to date. Follow-up of uninfected children born to women enrolled in study PACTG 076 (from birth to a median age of 4.2 years) has not revealed any difference in growth, neurodevelopment, or immunologic status among infants born to women who received zidovudine for prevention of maternal-fetal transmission of HIV compared with those born to women who received placebo.

Antiretroviral Therapy during Pregnancy

Recommendations for use of antiretroviral agents for the treatment of HIV infection in pregnant HIV-infected women generally are the same as those for nonpregnant HIV-infected adults, and women should receive optimal antiretroviral therapy regardless of pregnancy status. Although zidovudine is the only antiretroviral agent currently labeled for use in pregnant women, most clinicians do not consider pregnancy a contraindication for multiple-drug antiretroviral therapy when such therapy is indicated, especially during the second or third trimester.

Antiretroviral Therapy in Previously Treated Adults

A review of the agents that the patient already has received is essential. Resistance testing (performed while the patient is still receiving the old regimen) is useful in maximizing the number of active drugs in the new regimen. Viral resistance is an important, but not the only, reason for treatment failure.

Initial Antiretroviral Therapy in Treatment-naive Adults

Antiretroviral therapy in HIV-infected adults who are treatment naive (have not previously received antiretroviral therapy) should be initiated with a potent multiple-drug regimen. Treatment should be aggressive with the goal of maximal suppression of viral load to undetectable levels.

Classification of Antiretroviral Agents

Antiretroviral agents are synthetic antiviral agents that have antiviral activity against human immunodeficiency virus (HIV) and are used in the management of HIV infection. There currently are 5 different classes of antiretroviral agents commercially available: nucleoside reverse transcriptase inhibitors (NRTIs), HIV protease inhibitors, nonnucleoside reverse transcriptase inhibitors (NNRTIs), nucleotide reverse transcriptase inhibitors, and HIV fusion inhibitors.

Viread (Tenofovir Disoproxil)

Viread contains the active substance, tenofovir disoproxil. This active substance is an antiretroviral or antiviral medicine which is used to treat HIV or HBV or both. Tenofovir is a nucleotide reverse transcriptase inhibitor, generally known as an NRTI and works by interfering with the normal working of enzymes (in HIV reverse trans criptase; in hepatitis B DNA polymerase) that are essential for the viruses to reproduce themselves.