Efficacy of a nelfinavir- and nevirapine-containing salvage regimen

Clinical Utility of Current NNRTIs and Perspectives of New Agents in This Class under Development

Highly active antiretroviral therapy (HAART) has significantly reduced the number of deaths caused by AIDS. However, the antiviral efficacy of HAART comprising protease inhibitors (PIs) and nucleoside reverse transcriptase inhibitors (NRTIs) is frequently accompanied by a decrease in patients' quality of life. PI-based therapies often fail due to poor adherence caused by heavy pill burden, complex dosing schedules and undesirable side effects. The current trend is to switch from PI-based to PI-sparing regimens consisting of non-nucleoside reverse transcriptase inhibitors (NNRTIs) and NRTIs. Despite some encouraging results from NNRTI-containing therapies, two major concerns in using the currently available NNRTIs remain: 1) low genetic barrier to the emergence of resistance and 2) cross-resistance due to single mutations that often render the whole class of NNRTIs ineffective. Clearly, new and improved NNRTIs are needed to address these concerns.

Nelfinavir: a review of its use in the management of HIV infection

Nelfinavir (Viracept) is an orally administered protease inhibitor. In combination with other antiretroviral drugs (usually nucleoside reverse transcriptase inhibitors [NRTIs]), nelfinavir produces substantial and sustained reductions in viral load in patients with HIV infection. Nelfinavir may be used in the treatment of adults, adolescents and children aged >or=2 years with HIV infection. It can also be used in pregnancy. Resistance to nelfinavir may develop, but the most common mutation (D30N, appearing mainly in HIV-1 subtype B) does not confer resistance to other protease inhibitors, thereby conserving these agents for later use. Although less effective than lopinavir/ritonavir, the preferred first-line treatment in US guidelines, nelfinavir is positioned as an alternative agent for the treatment of adults and adolescents with HIV infection and is an option for those unable to tolerate other protease inhibitors. Nelfinavir also has a role in the management of pregnant patients as well as paediatric patients with HIV infection.

Lack of evidence for local immune activity in oral hairy leukoplakia and oral wart lesions

BACKGROUND

Oral warts, caused by human papillomavirus (HPV), and oral hairy leukoplakia (OHL) caused by Epstein-Barr virus (EBV), are common oral manifestations in HIV-infected persons. Although both conditions occur most often with reduced blood CD4+ T-cell numbers, oral warts and OHL rarely occur simultaneously, suggesting that dysfunctions in other secondary local immune parameters are also involved. The present study evaluated tissue-associated proinflammatory and T-helper cytokine and chemokine mRNA expression and the presence of T cells in each lesion.

METHODS

Biopsies were taken from lesion-positive and adjacent lesion-negative sites of HIV+ persons with oral warts or OHL and lesion-negative sites from HIV+ persons who were oral HPV or EBV DNA-positive (matched controls). Cytokine/chemokine mRNA expression was quantified by real-time polymerase chain reaction. CD3, CD4, and CD8 cells were identified by immunohistochemistry.

RESULTS

No differences were detected in tissue-associated cytokine/chemokine mRNA expression in warts or OHL when compared to lesion-negative sites. Immunohistochemical analysis of T cells showed CD8+ cells exclusively, but few cells were present in either lesion. No differences were detected between lesion-positive and -negative control sites of each pathologic condition.

CONCLUSION

Little evidence was found for local immune reactivity to either oral warts and OHL, suggesting that CD4+ T cells are a primary host defense against both oral warts and OHL, but with nonimmune factors potentially responsible for the divergent prevalence of each.

Oral opportunistic infections in HIV-positive individuals: review and role of mucosal immunity

Oral opportunistic infections in the HIV-positive individual have been documented since the first reports of the epidemic, with many lesions associated with reduced CD4(+) T lymphocyte cell count. The most common oral lesions seen in HIV disease prior to the advent of highly active antiretroviral therapy (HAART) were oropharyngeal candidiasis and oral hairy leukoplakia. However, since the advent of HAART while many oral lesions have decreased significantly the incidence of oral warts has surprisingly increased. Despite the correlation of diminished CD4(+) T lymphocyte count to the occurrence of these lesions, it is rare for the lesions to occur concurrently suggesting that each pathologic lesion type is associated with distinct host immune dysfunctions. To date, the oral opportunistic infection most frequently investigated is oropharyngeal candidiasis, where data suggests that both systemic and local immunity is important for protection against infection. In contrast, recent investigations into the host responses associated with oral hairy leukoplakia and oral warts show little to no evidence of systemic or mucosal immune responsiveness despite the presumed competence of several types of leukocytes other than CD4(+) T cells. Together these data are suggesting that susceptibility to oropharyngeal candidasis in HIV-positive persons is predominantly immune-based, whereas protection or susceptibility to oral hairy leukoplakia and oral warts may be more associated with factors other than mucosal immune function.

Effectiveness of Antiretroviral Therapy after Protease Inhibitor Failure: An Analytic Overview

To examine effectiveness of subsequent antiretroviral therapy (ART), studies published during the period of 1 January 1997 through 31 May 2003 involving patients who had failed a protease inhibitor (PI)-containing regimen and were switched to another regimen were reviewed. Twelve studies describing 1197 patients were analyzed. A total of 38% of patients had human immunodeficiency virus (HIV) RNA levels of <500 copies/mL at 24 weeks. After adjustment for baseline HIV RNA level, the rate of virologic suppression ranged from 16% for patients switching drugs within previously failed classes to 54% for nonnucleoside reverse-transcriptase inhibitor (NNRTI)-naive patients switched to boosted PI- and NNRTI-containing regimens. ART regimens in patients who failed a PI-containing regimen provided virologic suppression only in a few patients. The best response was seen in NNRTI-naive patients receiving NNRTI- and boosted PI-containing regimens. New approaches are needed to achieve better suppression in pretreated HIV-infected patients.