A randomized controlled trial of single-class maintenance therapy with abacavir/lamivudine/zidovudine after standard triple antiretroviral induction therapy: final 96-week results from the FREE study.

OBJECTIVES: The aim of the study was to test the antiviral efficacy of a triple nucleoside reverse transcriptase inhibitor (NRTI) regimen, with potential beneficial metabolic effects, as maintenance therapy after induction with dual NRTIs and a boosted protease inhibitor (PI). METHODS: An open-label, noninferiority study was carried out. Antiretroviral therapy (ART)-naïve patients with CD4 count ≤ 350 cells/µL and HIV-1 RNA >30000 copies/mL (n=207) were treated with zidovudine/lamivudine and lopinavir/ritonavir. After achieving HIV-1 RNA <50 copies/mL on two consecutive occasions between weeks 12 and 24 after baseline, 120 patients (baseline: median HIV-1 RNA 5.19 log10 copies/mL; median CD4 count 180 cells/µL) were randomized to receive abacavir/lamivudine/zidovudine (ABC/3TC/ZDV) (n=61) or to continue the PI-based ART (n=59). RESULTS: For the proportions of patients (intention-to-treat; missing=failure) with HIV-1 RNA <400 copies/mL (PI group, 66%; ABC/3TC/ZDV group, 71%) and <50 copies/mL (PI group, 63%; ABC/3TC/ZDV group, 62%) at 96 weeks, switching to ABC/3TC/ZDV was noninferior compared with continuing the PI regimen; the difference in failure rate (ABC/3TC/ZDV minus PI) was -4.4 percentage points [95% confidence interval (CI) -21.0 to +12.3 percentage points] and +0.4 percentage points (95% CI -16.9 to +17.7 percentage points), respectively. In the per protocol analysis, the difference in virological failure for HIV-1 RNA >400 copies/mL (0 of 39 patients in the PI group and two of 45 patients in the NRTI group) and for HIV-1 RNA >50 copies/mL (two of 39 and three of 45 patients, respectively) was +4.4 percentage points (95% CI -2.1 to +11.0 percentage points) and +1.5 percentage points (95% CI -8.6 to +11.7 percentage points), respectively, also showing noninferiority. Serum lipids significantly improved in the NRTI group, but not in the PI arm. CONCLUSIONS: A single-class NRTI regimen after successful induction with standard ART had similar antiviral efficacy compared to continuation of a PI-based regimen at 96 weeks after baseline, with improved serum lipids.

Leukocyte activation and cytokine production during experimental human endotoxemia.

Background: At present, it is unclear whether in experimental endotoxemia, the pro-inflammatory response observed in healthy volunteers is followed by an anti-inflammatory response, as observed in patients with sepsis. We studied the evolution of a number of inflammatory parameters during a prolonged period (24 h) after infusion of endotoxin in healthy subjects. Methods: Six healthy male subjects received an infusion of endotoxin (4 ng/kg body weight). Blood was drawn before, and at various intervals up to and including 24 h after, endotoxin infusion. Circulating cytokine levels, leukocyte activation surface markers, plasma lactoferrin, and neopterin levels were measured, and clinical signs and symptoms were noted during a 24-h period. Monocyte and neutrophil activation after endotoxin infusion is investigated in relation to the inflammatory response. The extent of neutrophil and monocyte activation was correlated to clinical markers and blood levels of inflammatory mediators and cytokines. Results: Tumor necrosis factor-alpha appeared 30 min after infusion in the circulation, peaking (5665+/-1910 pg/ml) at 2 h. Interleukin-10 appeared 60 min after infusion, peaking (427+/-348 pg/ml) at 3 h. The expression of leukocyte activation markers increased significantly after infusion. Expression of HLA-DR on monocytes decreased significantly after 3 h (P=0.03). There was a correlation between the TNF-alpha:IL-10 ratio and the CD11b:HLA-DR ratio (P=0.03). Conclusions: During experimental human endotoxemia, an initial pro-inflammatory response is successfully compensated by an anti-inflammatory response, leading to homeostasis. This is in contrast to what happens in septic patients with compensatory anti-inflammatory response syndrome. The inflammatory balance, expressed as the cytokine pro:anti-inflammatory ratio, is reflected at a cellular level.