A preliminary study of ritonavir, an inhibitor of HIV-1 protease, to treat HIV-1 infection.

Background: Ritonavir is a potent inhibitor in vitro of human immunodeficiency virus type 1 (HIV-1) protease, which is needed for virions to mature and become infective. We assessed the safety and efficacy of ritonavir in patients with HIV-1 infection.

Methods: We administered ritonavir orally to 62 patients in one of four dosages during a 12-week trial containing a 4-week randomized, placebo-controlled, double-blinded phase followed by an 8-week dose-blinded phase.

Assessment of antiretroviral therapy by plasma viral load testing: standard and ICD HIV-1 p24 antigen and viral RNA (QC-PCR) assays compared.

To assess the utility of quantitative competitive-polymerase chain reaction (QC-PCR) measurements of plasma human immunodeficiency virus type 1 (HIV-1) RNA and other viral load markers for assessment of antiretroviral therapy, we used archived cryopreserved specimens from a randomized controlled clinical trial of 135 patients (CD4+ T cell count < or = 500/mm3), comparing zidovudine (500 mg/day) versus the nonnucleoside reverse transcriptase inhibitor L-697, 661 (50, 300, or 1,000 mg daily). We evaluated treatment-associated changes in plasma viral load by standard and immune complex-dissociated (ICD) HIV-1 p24 antigen assays, and, in a representative subset of patients (n = 46), by QC-PCR determination of virion-associated HIV-1 RNA. At baseline, HIV-1 RNA was quantifiable by QC-PCR in all patients tested (100%), whereas standard and ICD HIV-1 p24 antigen tests were positive (> or = 30 pg/ml) in 42% and 56%, respectively.

Pharmacokinetics of an anti-human immunodeficiency virus antisense oligodeoxynucleotide phosphorothioate (GEM 91) in HIV-infected subjects.

Human pharmacokinetics of an antisense oligodeoxynucleotide phosphorothioate (GEM 91) developed as an anti-human immunodeficiency virus (HIV) agent was carried out in this study. 35S-Labeled GEM 91 was administered to six HIV-infected individuals by means of 2-hour intravenous infusions at a dose of 0.1 mg/kg.

Clinical evaluation of branched DNA signal amplification for quantifying HIV type 1 in human plasma.

Quantification of HIV-1 RNA in human plasma has provided unique insight into AIDS pathogenesis and promises to hasten progress in antiretroviral therapy and vaccine research. However, no generally available HIV-1 RNA assay has yet been subjected to rigorous clinical testing or to comparative evaluation with research-based RNA assays using large numbers of well-characterized clinical specimens. In this study, the Chiron Quantiplex branched DNA (bDNA) signal amplification assay was used to measure viral RNA in the plasma of 152 HIV-1-positive individuals at all stages of infection and in 12 patients before and after initiating zidovudine therapy.

Is there a role for non-nucleoside reverse transcriptase inhibitors in the treatment of HIV infection?

Because the efficacy of currently approved antiretroviral agents used as prolonged monotherapy is limited, there is an urgent need for alternative agents for the treatment of HIV infection. We review the development of a diverse group of new compounds, the non-nucleoside reverse transcriptase inhibitors (NNRTIs), which are potent and specific inhibitors of HIV replication. Early clinical experience with the NNRTIs has demonstrated antiviral activity and a high therapeutic index, but some patients rapidly develop viral strains resistant to these drugs.

Knowledge and self-reported use of universal precautions in a university teaching hospital.

This article reports a study of knowledge and self-reported use of universal precautions by professionals (individuals on the medical staff, in nursing service, in the laboratory, and in the social service, pastoral care, and respiratory care departments) and nonprofessionals (individuals working in the dietary and environmental services departments) in a university teaching hospital. Nonprofessional workers were found to be less knowledgeable about universal precautions than were professional workers. Appropriate use of universal precautions significantly correlated with a worker's perceived risk of exposure (positively correlated), the belief that HIV is easy to "catch" (negatively correlated), and the extent of the worker's involvement with HIV-infected patients (positively correlated).

Major expansion of CD8+ T cells with a predominant V beta usage during the primary immune response to HIV.

A SIGNIFICANT proportion (up to 70%) of individuals experience an acute clinical syndrome of varying severity associated with primary infection with the human immunodeficiency virus (HIV). We report here studies on six individuals who showed an acute HIV syndrome which generally resolved within four weeks, concomitant with a dramatic downregulation of viraemia. To characterize the T-cell-mediated primary immune response to HIV, we used combined semiquantitative polymerase chain reaction assay and cytofluorometry to analyse the T-cell antigen receptor repertoire in sequential peripheral blood mononuclear cells from the patients.

Evolving understanding of the immunopathogenesis of HIV.

Understanding of the immunopathogenesis of HIV infection is becoming more advanced as the activity of HIV infection in lymph nodes is appreciated and as improved virological measures permit more accurate quantitation of viral burden in patients at all stages of HIV disease. Although CD4+ cell counts remain important prognostic indicators, their role as a surrogate for direct antiviral activity has been questioned and increasing focus has been placed on more direct quantitative viral measures that are now available. After an initial explosive burst of viral replication during acute seroconversion that is downregulated by the immune system, these newer markers have revealed that viral replication is ongoing during the so-called "clinically latent" period of HIV infection.

Measurement of cryptococcal antigen in serum and cerebrospinal fluid: value in the management of AIDS-associated cryptococcal meningitis.

The value of monitoring titers of cryptococcal antigen in serum and cerebrospinal fluid (CSF) during therapy for AIDS-associated cryptococcal meningitis was evaluated. Baseline and final titers of antigen in serum and CSF from participants in two studies of such therapy were categorized as increased (a rise of at least two dilutions), unchanged, or decreased (a fall of at least two dilutions). There was no correlation between outcome and changes in serum titers of cryptococcal antigen during treatment for acute meningitis or during suppressive therapy.

Issues in combination antiretroviral therapy: a review.

High viral burden and replication persist during all phases of human immunodeficiency virus (HIV) disease. Although monotherapy has yielded considerable benefits, these benefits are neither absolute nor durable. Combination therapy has multiple goals: to reduce viral replication and burden; to relieve drug toxicity; to attenuate viral mutations leading to resistance and possibly to conversion from non-syncytium-inducing to syncytium-inducing virus; and to broaden the spectrum of specific cells and tissues in which antiretroviral agents are active.

Pathogenicity and diversity of HIV and implications for clinical management: a review.

Genetic variation of human immunodeficiency virus (HIV) over time is an important consideration in long-term antiretroviral therapy, in all likelihood affecting the course of HIV disease and its response to antiretroviral therapy. Viral replication persists throughout HIV disease, and viral burden is correlated with disease stage. CD4+ T-helper cells, a prime target for HIV, appear responsible for direct cellular and humoral responses to infection.

Determination of plasma viral load in HIV-1 infection by quantitative competitive polymerase chain reaction.

Objectives: To better characterize viral load profiles through the course of HIV-1 disease and in response to treatment, and to further evaluate quantitative competitive polymerase chain reaction for measurement of viral load, we extended our comparative evaluation of this and other viral load measurements to a total of 118 patients, representing all stages of HIV-1 disease.

Design: For cross-sectional analysis across the spectrum of HIV-1 disease, plasma viral load was evaluated in 112 HIV-1-infected patients by quantitative competitive polymerase chain reaction analysis, plasma p24 antigen assay, plasma immune complex-dissociated p24 antigen assay and an endpoint dilution viral culture. Longitudinal specimens from six additional patients were analyzed, extending from the time of presentation with symptomatic acute HIV-1 infection through up to more than 2 years of follow-up.

A short-term clinical evaluation of L-697,661, a non-nucleoside inhibitor of HIV-1 reverse transcriptase. L-697,661 Working Group.

Background: The non-nucleoside reverse transcriptase inhibitors are novel antiretroviral agents with selective activity in vitro against human immunodeficiency virus type 1 (HIV-1). They act through direct inhibition of reverse transcriptase and are not incorporated into DNA.

Methods: We evaluated a pyridinone non-nucleoside reverse transcriptase inhibitor, L-697,661, in separate six-week double-blind trials in patients with HIV-1 infection whose CD4 counts ranged from 200 to 500 cells per cubic millimeter (68 patients) or less than 200 cells per cubic millimeter (67 patients).

Kinetics of human immunodeficiency virus type 1 (HIV-1) DNA and RNA synthesis during primary HIV-1 infection.

HIV-1 replication and viral burden in peripheral blood mononuclear cells (PBMC) have been reported to be high in primary infection but generally very low during the prolonged period of clinical latency. It is uncertain precisely when this transition occurs during the HIV-1 infection and what the relationship is between the changes in HIV-1 replication versus the clearance of infected cells in the overall control of viral replication. In the present study, the kinetics of viral burden (i.

A molecular clone of HIV-1 tropic and cytopathic for human and chimpanzee lymphocytes.

Previous studies of HIV-1 replication in chimpanzee lymphocytes have been limited to a small number of virus isolates which generally replicated poorly and without cytopathic effect. Here, we describe an HIV-1 provirus (SG3), cloned as a single proviral unit, which replicates more efficiently in chimpanzee than in human lymphocytes, resulting in syncytium formation and cell death. This provirus also replicates efficiently and with extraordinary cytopathic effect in immortalized human T-cell lines.

Prevention of relapse of histoplasmosis with itraconazole in patients with the acquired immunodeficiency syndrome.

Objective: To assess the efficacy and safety of itraconazole in preventing relapse of histoplasmosis after induction therapy with amphotericin B in patients with the acquired immunodeficiency syndrome (AIDS) and disseminated histoplasmosis.

Design: A prospective, multicenter, open-label clinical trial, with follow-up for at least 52 weeks.

Setting: Tertiary care hospitals participating in a clinical investigation sponsored by the National Institutes of Allergy and Infectious Diseases (AIDS Clinical Trial Group and Mycoses Study Group).

High levels of HIV-1 in plasma during all stages of infection determined by competitive PCR.

Quantitative competitive polymerase chain reaction (QC-PCR) methods were used to quantify virion-associated human immunodeficiency virus type-1 (HIV-1) RNA in plasma from 66 patients with Centers for Disease Control stage I to IVC1 infection. HIV-1 RNA, ranging from 100 to nearly 22,000,000 copies per milliliter of plasma (corresponding to 50 to 11,000,000 virions per milliliter), was readily quantified in all subjects, was significantly associated with disease stage and CD4+ T cell counts, and decreased by as much as 235-fold with resolution of primary infection or institution of antiretroviral therapy. Plasma virus levels determined by QC-PCR correlated with, but exceeded by an average of 60,000-fold, virus titers measured by endpoint dilution culture.

Itraconazole therapy for blastomycosis and histoplasmosis. NIAID Mycoses Study Group.

Objective: To assess the efficacy and toxicity of orally administered itraconazole in the treatment of nonmeningeal, nonlife-threatening forms of blastomycosis and histoplasmosis.

Design: Prospective, nonrandomized, open trial.

Setting: Multicenter trial at 14 university referral centers.

Treatment of HIV infection: the antiretroviral nucleoside analogues. Nucleoside analogues: adverse effects.

The three approved nucleoside analogues are fairly well tolerated, and only a few patients have to discontinue therapy permanently. However, because clinical experience is limited, especially with ddI and ddC, delayed toxicities are likely to emerge over time. In addition, physicians should be vigilant for overlapping toxicities from combination therapy with these and other medications.