Efficacy of etravirine combined with darunavir or other ritonavir-boosted protease inhibitors in HIV-1-infected patients: an observational study using pooled European cohort data

OBJECTIVES

This observational study in antiretroviral treatment-experienced, HIV-1-infected adults explored the efficacy of etravirine plus darunavir/ritonavir (DRV group; n = 999) vs. etravirine plus an alternative boosted protease inhibitor (other PI group; n = 116) using pooled European cohort data.

METHODS

Two international (EuroSIDA; EUResist Network) and five national (France, Italy, Spain, Switzerland and UK) cohorts provided data (collected in 2007-2012). Stratum-adjusted (for confounding factors) Mantel-Haenszel differences in virological responses (viral load < 50 HIV-1 RNA copies/mL) and odds ratios (ORs) with 95% confidence intervals (CIs) were derived.

RESULTS

Baseline characteristics were balanced between groups except for previous use of antiretrovirals (≥ 10: 63% in the DRV group vs. 49% in the other PI group), including previous use of at least three PIs (64% vs. 53%, respectively) and mean number of PI resistance mutations (2.3 vs. 1.9, respectively). Week 24 responses were 73% vs. 75% (observed) and 49% vs. 43% (missing = failure), respectively. Week 48 responses were 75% vs. 73% and 32% vs. 30%, respectively. All 95% CIs around unadjusted and adjusted differences encompassed 0 (difference in responses) or 1 (ORs). While ORs by cohort indicated heterogeneity in response, for pooled data the difference between unadjusted and adjusted for cohort ORs was small.

CONCLUSIONS

These data do not indicate a difference in response between the DRV and other PI groups, although caution should be applied given the small size of the other PI group and the lack of randomization. This suggests that the efficacy and virology results from DUET can be extrapolated to a regimen of etravirine with a boosted PI other than darunavir/ritonavir.

Signatures of Lévy flights with annealed disorder

We present theoretical and experimental results of Lévy flights of light originating from a random walk of photons in a hot atomic vapor. In contrast to systems with quenched disorder, this system does not present any correlations between the position and the step length of the random walk. In an analytical model based on microscopic first principles including Doppler broadening we find anomalous Lévy-type superdiffusion corresponding to a single-step size distribution P(x)∝x^{-(1+α)}, with α≈1. We show that this step size distribution leads to a violation of Ohm's law [T_{diff}∝L^{-α/2}≠L^{-1}], as expected for a Lévy walk of independent steps. Furthermore, the spatial profile of the transmitted light develops power-law tails [T_{diff}(r)∝r^{-3-α}]. In an experiment using a slab geometry with hot Rb vapor, we measured the total diffuse transmission T_{diff} and the spatial profile of the transmitted light T_{diff}(r). We obtained the microscopic Lévy parameter α under macroscopic multiple scattering conditions paving the way to investigation of Lévy flights in different atomic physics and astrophysics systems.

Atomic lighthouse effect

We investigate the deflection of light by a cold atomic cloud when the light-matter interaction is locally tuned via the Zeeman effect using magnetic field gradients. This "lighthouse" effect is strongest in the single-scattering regime, where deviation of the incident field is largest. For optically dense samples, the deviation is reduced by collective effects, as the increase in linewidth leads to a decrease in magnetic field efficiency.

Self-organization in cold atomic gases: a synchronization perspective

We study non-equilibrium spatial self-organization in cold atomic gases, where long-range spatial order spontaneously emerges from fluctuations in the plane transverse to the propagation axis of a single optical beam. The self-organization process can be interpreted as a synchronization transition in a fully connected network of fictitious oscillators, and described in terms of the Kuramoto model.