
Effects of Changing HIV Therapy at Lower Versus Higher Viral Loads
HIV InfectionsThis study will look at people who have been taking anti-HIV drugs but still have detectable levels of HIV. The purpose of the study is to find out what happens in those people who change anti-HIV drugs when their viral load reaches 200 copies compared to those who change anti-HIV drugs when their viral load reaches 10,000 copies. This study will also look at drug resistance (how well HIV responds to drugs), viral fitness (how well drug-resistant HIV copies itself), and immunologic reconstitution (how well the immune system recognizes various infections, including HIV). Many patients experience virologic relapse (increase in viral load after sustained viral load suppression) within 1 to 2 years of taking anti-HIV drugs. The approach to treatment for patients who experience virologic relapse while on a highly active antiretroviral therapy (HAART) has not been defined. Current guidelines recommend switching to a new treatment regimen as soon as possible to prevent HIV from becoming even more resistant to anti-HIV drugs. However, there is evidence that patients can benefit from staying on the same HAART drugs, even after virologic relapse. This study wants to find what happens when drugs are changed immediately after virologic relapse (when the viral load is lower) compared to what happens if drugs are changed only after a delay (when the viral load is higher).

A Phase III Study Comparing Two Different Anti-HIV Drug Combinations in HIV-Positive Patients Without...
HIV InfectionsThe purpose of this study is to see how safe a new protease inhibitor (PI) is and how well it fights HIV infection. A PI is a drug that stops HIV from using healthy cells to make more virus. This study will compare the new PI combination of ABT-378 plus ritonavir (RTV) with another PI, nelfinavir (NFV). Earlier studies suggest ABT-378/RTV will be just as good as and perhaps better than NFV at fighting HIV infection.

A Study of the Safety and Effectiveness of Combination Anti-HIV Therapy in HIV-Infected Adults
HIV InfectionsThe purpose of this study is to see if a certain combination of anti-HIV drugs is safe and effective in HIV-infected patients. The drug combination includes a tablet containing lamivudine and zidovudine (called Combivir) plus abacavir plus efavirenz.

Atazanavir Used in Combination With Other Anti-HIV Drugs in HIV-Infected Infants, Children, and...
HIV InfectionsThe purpose of this study was to find a safe and tolerable dose of the protease inhibitor (PI) atazanavir (ATV), with or without a low-dose boost of the PI ritonavir (RTV), when taken with other anti-HIV drugs in HIV infected infants, children, and adolescents. Advancements in anti-HIV drugs for HIV infected children and adolescents have been hard to make, in part because these patients often do not take the drugs as prescribed. ATV may be a better option because it is available in the form of powder which children and adolescents may be more willing to take regularly. Using a low dose of RTV as a boosting agent for ATV may also increase the chances of virologic response of highly active antiretroviral treatment (HAART)-experienced patients. This study aimed to find safe and tolerable doses of ATV with or without low-dose RTV boost in infants, children, and adolescents. For this study, participants were enrolled in the United States and South Africa.

Four-Drug Combination Therapy With Zidovudine, Lamivudine, 1592U89 (Abacavir), and 141W94 (Amprenavir)...
HIV InfectionsThe purpose of this study is to see if the multidrug combination of zidovudine (ZDV), lamivudine (3TC), 1592U89 (abacavir [ABC]), and 141W94 (amprenavir [APV]) is a safe and effective treatment for HIV-infected patients and if there is a reduction of active HIV in blood and other tissues. HIV infection is a life-changing illness and new HIV treatments must be tested. This study will test if a 4-drug combination will reduce HIV virus activity in blood and other tissues and if it is safe and well tolerated. Doctors also want to know if the multidrug combination is able to decrease viral activity over a long time period.

Safety of the Candidate Vaccine C4-V3 Alone or With Interleukin-12 (IL-12) in HIV-Infected Patients...
HIV InfectionsThe purpose of this study is to see if it is safe to give C4-V3, a possible HIV vaccine, alone or in conjunction with 4 different doses of interleukin-12 (IL-12), to HIV-infected patients who are taking anti-HIV drugs that have lowered the amount of HIV in patients' blood. (This study has been changed so that vaccine is administered alone or with 4 different doses of IL-12.) Immune cells known as cytotoxic T lymphocytes (CTLs) help destroy HIV-infected cells. However, in most patients, CTLs decrease over time. This allows HIV levels to rise and AIDS symptoms to develop. The C4-V3 vaccine contains small pieces of HIV protein that can boost CTL levels, allowing the body's immune system to fight HIV. Giving IL-12, a normal part of the immune system, with C4-V3 may make the vaccine more effective.

Effectiveness and Safety of Two Forms of Stavudine in HIV-Infected Patients
HIV InfectionsThe purpose of this study is to compare the safety and effectiveness of 2 forms of stavudine (d4T). One form is taken once a day (extended release) and the other form is taken twice a day (immediate release).

Safety and Effectiveness of Adding Either an HIV Vaccine, Interleukin-2, or Both to a Patient's...
HIV InfectionsThe purpose of this study is to see if adding an HIV vaccine (ALVAC-HIV vCP1452), IL-2 (interleukin-2, a protein found in the blood that helps boost the immune system), or both to anti-HIV-drug therapy is safe, tolerable, and effective in controlling viral load (level of HIV in the body). (This study has been changed to clarify drug name.) Anti-HIV drugs can help reduce a patient's viral load. However, HIV can still remain in CD4 cells (cells of the immune system that help fight infection). Combining an HIV vaccine, IL-2, or both with anti-HIV drugs may help reduce the number of HIV-infected cells.

Pharmacokinetics of Antiretroviral Agents in HIV-1 Infected Pregnant Women
HIV InfectionThis study will determine if blood levels of anti-HIV drugs in pregnant women change at different stages of pregnancy and if these changes require dosage adjustments in order to maintain adequate drug levels during pregnancy. Anti-HIV medications are recommended for HIV-infected women during pregnancy not only to treat their infection, but also to reduce the chance of passing the virus to the baby during pregnancy. Changes in the body that occur during pregnancy may affect how the body uses and eliminates these drugs, reducing their levels during pregnancy. Pregnant women 18 years of age or older who are infected with HIV may be eligible for this study. Candidates will have a medical history and physical examination, pregnancy test and blood tests. Participants will come to the NIH Clinical Center once every 6 to 12 weeks until around their 34th week (8 months) of pregnancy and then again at least 1 month after the birth of the baby to have blood drawn. A catheter (thin plastic tube) will be placed in a vein to avoid multiple needle sticks for blood sampling during the day. The first sample will be collected before the patient takes the morning doses of anti-HIV medicines and additional samples will be drawn at 1, 2, 4, 8 and 12 hours after taking the medication. A urine sample will also be collected at each visit.

Safety, Tolerability, and Anti-HIV Activity of PEG-Intron in HIV-Positive Children
HIV InfectionsThe purpose of this study is to see if PEG-Intron is safe and tolerated when given to children, to see how much gets into the blood and how long it stays in the blood, and to see how well it works to reduce viral load (level of HIV in the blood). PEG-Intron is an experimental drug that works differently than other anti-HIV medications. It decreases the ability of HIV to infect the T cells (a special type of cell that helps fight infection). PEG-Intron has been approved by the Food and Drug Administration (FDA) to treat hepatitis C in adults, but in this study, it is being used as an investigational agent for the treatment of HIV/AIDS. It has not been tested in children before and experience with PEG-Intron in adults is limited. (This protocol has been changed to reflect FDA approval of PEG-Intron for treating hepatitic C in adults.)