Efficacy of tenofovir and efavirenz in combination with lamivudine or emtricitabine in antiretroviral-naive patients in Europe.

BACKGROUND: The combination of tenofovir and efavirenz with either lamivudine or emtricitabine (TELE) has proved to be highly effective in clinical trials for first-line treatment of HIV-1 infection. However, limited data are available on its efficacy in routine clinical practice. METHODS: A multicentre cohort study was performed in therapy-naive patients initiating ART with TELE before July 2009. Efficacy was studied using ITT (missing or switch = failure) and on-treatment (OT) analyses. Genotypic susceptibility scores (GSSs) were determined using the Stanford HIVdb algorithm. RESULTS: Efficacy analysis of 1608 patients showed virological suppression to <50 copies/mL at 48 weeks in 91.5% (OT) and 70.6% (ITT). Almost a quarter of all patients (22.9%) had discontinued TELE at week 48, mainly due to CNS toxicity. Virological failure within 48 weeks was rarely observed (3.3%, n = 53). In multilevel, multivariate analysis, infection with subtype B (P = 0.011), baseline CD4 count <200 cells/mm³ (P < 0.001), GSS <3 (P = 0.002) and use of lamivudine (P < 0.001) were associated with a higher risk of virological failure. After exclusion of patients using co-formulated compounds, virological failure was still more often observed with lamivudine. Following virological failure, three-quarters of patients switched to a PI-based regimen with GSS <3. After 1 year of second-line therapy, viral load was suppressed to <50 copies/mL in 73.5% (OT). CONCLUSIONS: In clinical practice, treatment failure on TELE regimens is relatively frequent due to toxicity. Virological failure is rare and more often observed with lamivudine than with emtricitabine. Following virological failure on TELE, PI-based second-line therapy was often successful despite GSS <3.

Macrophage activation and HIV infection: can the Trojan horse turn into a fortress?

Macrophages are infected early during HIV infection and are thought to play the role of a Trojan horse by spreading infection in tissues. Most recent studies point out to a more complex role for macrophages in HIV infection: macrophages could contribute to both host defense and viral persistence and pathogenesis. Infected macrophages are a reservoir for HIV and modulate apoptosis of T cells present in their vicinity. Also, a functional impairment of HIV-infected macrophages may play a role in AIDS pathogenesis. Nevertheless, both activation and differentiation of monocyte/macrophages can interfere with susceptibility of these cells to infection. Therefore, a wide variety of stimuli result in HIV suppression through macrophage activation. At present times, a dynamic view on the role of macrophages in HIV infection arises which indicates that macrophages are a target for the virus and at the same time regulate its replication. Therefore, macrophages are at the cross-road between protection and pathogenesis in HIV infection due to their involvement both as a viral target and a key modulator of non-specific and specific immune responses. Future studies will help unravel the cellular and molecular mechanisms that underlie HIV-macrophage interactions and might result in new vaccine and/or therapeutic strategies.