Active clinical trials for "HIV Infections"

This study will examine the safety and immune response to a two-part HIV vaccine. Healthy volunteers who are at low risk of HIV infection will receive either active vaccine or a placebo.

The Luo tribe of Kisumu, Kenya, does not traditionally practice male circumcision (MC). This study will work with the Luo tribe to test the effectiveness of MC on reducing the risk of HIV infections in young men.

The purpose of this study is to see if it is safe to give an HIV vaccine (vCP205) to volunteers who received an HIV vaccine at least 2 years ago, and to study how the immune system responds to this vaccine. Vaccines are given to people to try to resist infection or prevent disease. There are a number of different HIV vaccines that are currently being tested. The vaccines that seem to be the most promising are canarypox vaccines, known as ALVAC vaccines; the vaccine tested in this study is ALVAC-HIV vCP205. This study will look at the safety of the vaccine and how the immune system responds to it.

To evaluate the safety and immunogenicity of HIV p17/p24:Ty-VLP (virus-like particles) vaccine in uninfected volunteers. Specifically, to determine whether the vaccine formulated with and without alum induces CD8+ cytotoxic T lymphocytes ( CTLs ) that may be cross-reactive against multiple HIV-1 stains. Also, to determine whether boosting with the vaccine orally or rectally will help induce mucosal antibody responses. Induction of CD8+ CTL activity is considered a critical property for a candidate vaccine. Additionally, since the majority of HIV-1 infections occur after inoculation of a mucosal surface, it is desirable to induce mucosal immunity as well as systemic immunity. The HIV p17/p24:Ty-VLP vaccine may potentially induce both CTL and mucosal antibody responses against HIV-1.

To determine the safety of and immune response to vaccinia-derived HIV-1 recombinant envelope glycoprotein (gp160) at a dose of 200 mcg in human volunteers; to evaluate duration of antibody response and its relationship to the dose and frequency of inoculation. Although recent advances have been made in antiviral therapy against AIDS, there is currently no cure for AIDS. It is likely that the ultimate control of the disease depends on the development of safe and effective vaccines against HIV.

To evaluate the safety and immunogenicity of an accelerated schedule of recombinant canarypox vaccine ALVAC-HIV MN120TMG (vCP205) versus control followed by boost with rgp120/HIV-1 SF2 vaccine in HIV-negative volunteers. Frequent injections of ALVAC-HIV vCP205 may result in more rapid induction of cytotoxic T-lymphocytes. This trial will evaluate whether an accelerated vaccination schedule can produce immunological responses comparable to those obtained in other trials of ALVAC-HIV vCP205.

To compare the long-term virologic response to combination therapy with two protease inhibitors, i.e., nelfinavir (NFV) + saquinavir soft gel capsule (SQVsgc) and delavirdine (DLV) or combination lamivudine/zidovudine (3TC/ZDV, Combivir) versus NFV and 3TC/ZDV, in the proportion of patients demonstrating virologic success (< 500 copies/ml HIV RNA) at week 48, without prior virologic or clinical failure. To evaluate the safety and tolerance of combination protease inhibitors. To evaluate the durability of virologic response as assessed by the Roche Ultra Sensitive assay (< 200 copies/ml) and culturable virus. To compare time to a confirmed virologic response (two consecutive plasma HIV RNA levels < 500 copies/ml) or to a confirmed treatment relapse following a confirmed virologic response across the treatment arms. To evaluate biologic phenotype (non-syncytium inducing versus syncytium inducing capacity) and the evolution and patterns of viral resistance among patients with confirmed treatment failures at or after weeks 16 to 24. To compare immunologic benefits, as measured by longitudinal CD4/CD8 cell count profiles. To evaluate the influence of baseline virologic and immunologic parameters on the magnitude and duration of plasma HIV RNA response. To compare virologic response between the two dose schedules of NFV and SQVsgc (bid vs tid) and between NFV and SQVsgc with either DLV or combination 3TC/ZDV. To evaluate compliance and exploratory population pharmacometrics. Past studies have shown that combination therapies not only will result in better clinical outcomes but may prolong the effects of therapy. The enhanced effects seen with combination therapies are likely related to a greater suppression of HIV replication and alterations in resistance patterns. Both in vitro and in vivo studies suggest that triple-drug therapy may have an advantage over one- and two-drug regimens. Therefore, triple-drug therapy appears to be an important strategy in the treatment of HIV infection.

To quantitate in an HIV-infected population the percentage of patients demonstrating the "booster" phenomenon (attainment of a positive response to a second tuberculin purified protein derivative skin test when the first skin test was negative); to determine the relationship between the booster phenomenon and CD4-positive lymphocyte cell counts; to detect any relationship between the booster phenomenon and HIV exposure category. The accuracy of skin testing to detect Mycobacterium tuberculosis (MTb) infection is dependent upon the host's ability to mount a delayed-type hypersensitivity (DTH) reaction; however, the DTH response may be impaired or absent in patients with impaired cell-mediated immunity, a classic characteristic of HIV infection. Patients in whom immunity is diminished, but not absent, may test negative the first time a purified protein derivative skin test for MTb is administered, but if the same skin test is repeated, a positive DTH response may then be elicited. This occurrence is known as the "booster" phenomenon.

To expand the safety information regarding MN rsgp 120/HIV-1 formulated with QS21 or alum. To evaluate the immunogenicity of low doses of MN rsgp 120/HIV-1 formulated with QS21 or alum. Studies to date indicate that there may be a dose-sparing effect with the use of QS21. In animal studies, when QS21 has been employed as an adjuvant, it shifted both the dose response curve and allowed less antigen to elicit equivalent binding antibody titers to the rgp120 protein. There may also be an acceleration in the course of antibody response after both the first and the second immunizations. Although the final titers in response to vaccine given in both alum and QS21 appear similar after 3 doses in humans, this plateau may be reached more readily, and with a lower antigen dose, when using QS21 as an adjuvant. In addition, it has been established that using a lower dose of antigen may elicit an immune response which is characterized by lymphoproliferation and production of TH1-like cytokines such as INF-gamma, interleukin-2, interleukin-4, interleukin-5 and interleukin-10.

The purpose of this study is to see if giving the ALVAC vCP1452 anti-HIV vaccine alone or with another vaccine called AIDSVAX B/B to babies of HIV-positive mothers is safe. The study will also look at how these vaccines affect a baby's immune system. Most HIV-positive children get HIV from their mothers during pregnancy or birth. Treatment with anti-HIV drugs can reduce the baby's risk of getting HIV. Vaccines also may help prevent HIV infection. This study will look at whether the ALVAC vCP1452 vaccine and the AIDSVAX B/B vaccine can help the body fight off HIV infection. There is no chance of getting HIV infection from the vaccines. (This study has been changed. In earlier versions, ALVAC vCP205 and AIDSVAX B/E were going to be used.)