Explore the vast range of titles available.

Background Multi-class resistance, intolerance, and drug–drug interactions can result in unique antiretroviral (ART) combinations for heavily treatment-experienced (HTE) people living with HIV (PLWH). We aimed to compare clinical outcomes between HTE and non-HTE PLWH. Methods Eligible ART-experienced PLWH in care in the OPERA® Cohort were identified in a cross-sectional manner on December 31, 2016 and observed from the date of initiation of the ART regimen taken on December 31, 2016 until loss to follow up, death, study end (December 31, 2018), or becoming HTE (non-HTE group only). In the absence of resistance data, HTE was defined based on the ART regimens used (i.e., exposed to ≥ 3 core agent classes or regimen suggestive of HTE). Time to virologic undetectability, failure, and immunologic preservation were assessed using Kaplan–Meier methods; cumulative probabilities were compared between the two groups. Regimen changes, incident morbidities, and death were described. Results A total of 24,183 PLWH (2277 HTE PLWH, 21,906 non-HTE) were followed for a median of 28 months (IQR 21, 38). Viremic HTE PLWH (viral load [VL] ≥ 50 copies/mL) were less likely to achieve undetectability (VL < 50 copies/mL; 24-month cumulative probability: 80% [95% Confidence Interval 77–82]) than their non-HTE counterparts (85% [84–86]). No difference was observed in the probability of maintaining VLs < 200 copies/mL over the first 48 months after achieving suppression (< 50 copies/mL). HTE PLWH were less likely than non-HTE PLWH to maintain CD4 cell counts ≥ 200 cells/µL (24-month cumulative probability: 95% HTE [91–93]; 97% non-HTE [97–97]), and more likely to change regimens (45% HTE; 41% non-HTE). Incident non-AIDS defining event (ADE) morbidities were common in both populations, though more likely among HTE PLWH (45%) than non-HTE PLWH (35%). Incident ADE morbidities and deaths were uncommon among HTE (ADEs 5%; deaths 2%) and non-HTE (ADEs 2%; deaths 1%) PLWH. Conclusions HTE PLWH were at greater risk of unfavorable treatment outcomes than non-HTE PLWH, suggesting additional therapeutic options are needed for this vulnerable population.

Introduction The first complete long-acting antiretroviral therapy (ART) regimen, cabotegravir + rilpivirine long-acting (CAB + RPV LA) injectable, was approved in the US for HIV-1 treatment in individuals on a stable antiretroviral regimen with a viral load < 50 copies/mL, no treatment failure history, and no resistance to either cabotegravir or rilpivirine. We describe injection schedule adherence and virologic effectiveness of CAB + RPV LA in routine clinical care in the US. Methods From the OPERA ® cohort, all adults with HIV who received their first CAB + RPV LA injection and ≥ 1 continuation injections between 21 January 2021 and 15 March 2022 were included. The injection target date was updated monthly and set to the same date of the month as the previous injection. Continuation injections administered within 7 days before or after the target date were considered on time, as per the label. Virologic undetectability (viral load < 50 copies/mL), suppression (viral load < 200 copies/mL), and confirmed virologic failure (2 consecutive viral loads ≥ 200 copies/mL or 1 viral load ≥ 200 copies/mL followed by discontinuation) were described among individuals with a viral load < 50 copies/mL at initiation and ≥ 1 follow-up viral load. Results Among 321 individuals on CAB + RPV LA, 90% of the continuation injections were administered on time (within ± 7 days of the target date). Of the 237 individuals with a viral load < 50 copies/mL at initiation and ≥ 1 follow-up viral load, nearly all were undetectable (95%) or suppressed (99%) at their last viral load measurement, 96% maintained virologic suppression with all measured viral loads < 200 copies/mL, and four confirmed virologic failures were observed. Injection delays were infrequent, and did not affect virologic outcomes over the short term. Conclusion In this large US cohort, most monthly CAB + RPV LA injections were administered on time and high levels of virologic control were achieved. These results suggest that CAB + RPB LA injectable can be administered effectively during routine clinical care.

A direct measurement of cosmic-ray electrons and positrons with unprecedentedly high energy resolution reveals a spectral break at about 0.9 teraelectronvolts, confirming the evidence found by previous indirect measurements. A break in the cosmic-ray spectrum The spectrum of cosmic-ray electrons and positrons that arrive at Earth potentially contains information about the sources that accelerated them, and may reveal dark-matter annihilation. The spectrum has previously been measured directly up to around 2 teraelectronvolts (TeV), and indirectly up to around 5 TeV from ground-based Cherenkov arrays, which revealed a possible break in the spectrum. The Dark Matter Particle Explorer (DAMPE) Collaboration reports a direct measurement between 25 gigaelectronvolts and 4.6 TeV, which clearly reveals a spectral break at around 0.9 TeV. High-energy cosmic-ray electrons and positrons (CREs), which lose energy quickly during their propagation, provide a probe of Galactic high-energy processes 1 , 2 , 3 , 4 , 5 , 6 , 7 and may enable the observation of phenomena such as dark-matter particle annihilation or decay 8 , 9 , 10 . The CRE spectrum has been measured directly up to approximately 2 teraelectronvolts in previous balloon- or space-borne experiments 11 , 12 , 13 , 14 , 15 , 16 , and indirectly up to approximately 5 teraelectronvolts using ground-based Cherenkov γ-ray telescope arrays 17 , 18 . Evidence for a spectral break in the teraelectronvolt energy range has been provided by indirect measurements 17 , 18 , although the results were qualified by sizeable systematic uncertainties. Here we report a direct measurement of CREs in the energy range 25 gigaelectronvolts to 4.6 teraelectronvolts by the Dark Matter Particle Explorer (DAMPE) 19 with unprecedentedly high energy resolution and low background. The largest part of the spectrum can be well fitted by a ‘smoothly broken power-law’ model rather than a single power-law model. The direct detection of a spectral break at about 0.9 teraelectronvolts confirms the evidence found by previous indirect measurements 17 , 18 , clarifies the behaviour of the CRE spectrum at energies above 1 teraelectronvolt and sheds light on the physical origin of the sub-teraelectronvolt CREs.

Two-drug regimens (2DR) may address drug-drug interactions and toxicity concerns. Dolutegravir/lamivudine (DTG/3TC) 2DR was approved in the US for both treatment-naïve and treatment-experienced individuals with a viral load <50 copies/mL. This study describes real-world DTG/3TC 2DR treatment outcomes among treatment-experienced individuals, stratified by age, sex, and race. From the OPERA cohort, people with HIV with a viral load <50 copies/mL who switched from a commonly used three-drug regimen to DTG/3TC 2DR as per the label between April 8, 2019 and April 30, 2021 were included. Incidence rates (Poisson regression) for loss of virologic control (first viral load ≥50 copies/mL), confirmed virologic failure (2 viral loads ≥200 copies/mL or discontinuation after 1 viral load ≥200 copies/mL), and DTG/3TC 2DR discontinuation were estimated overall and stratified by age, sex, and race. The 787 individuals included were followed for a median of 13.6 months (IQR: 8.2, 22.3). Confirmed virologic failure occurred in ≤5 individuals. Loss of virologic control occurred at a rate of 14.0 per 100 person-years (95% CI: 11.7, 16.8). DTG/3TC 2DR discontinuation occurred at a rate of 17.5 per 100 person-years (95% CI: 15.0, 20.3); 4% discontinued for treatment-related reasons (viremia, adverse diagnosis, side effect, lab abnormality). For all outcomes, incidence rates were comparable across strata of age, sex, and race. This descriptive study demonstrates that DTG/3TC 2DR is an effective and well-tolerated treatment option for people with HIV with a viral load <50 copies/mL at switch, regardless of their age, sex, or race.

How many stars have formed in the Universe, and when did they do so? These fundamental questions are difficult to answer because there are systematic uncertainties in converting the light we observe into the total mass of stars in galaxies. The Fermi-LAT Collaboration addressed these questions by exploiting the way that gamma rays from distant blazars propagate through intergalactic space, which depends on the total amount of light emitted by all galaxies. The collaboration found that star formation peaked about 3 billion years after the Big Bang (see the Perspective by Prandini). Although this is similar to previous estimates from optical and infrared observations, the results provide valuable confirmation because they should be affected by different systematic effects. Science , this issue p. 1031 ; see also p. 995 Intergalactic gamma rays are used to determine the star formation history of the Universe. The light emitted by all galaxies over the history of the Universe produces the extragalactic background light (EBL) at ultraviolet, optical, and infrared wavelengths. The EBL is a source of opacity for gamma rays via photon-photon interactions, leaving an imprint in the spectra of distant gamma-ray sources. We measured this attenuation using 739 active galaxies and one gamma-ray burst detected by the Fermi Large Area Telescope. This allowed us to reconstruct the evolution of the EBL and determine the star formation history of the Universe over 90% of cosmic time. Our star formation history is consistent with independent measurements from galaxy surveys, peaking at redshift z ~ 2. Upper limits of the EBL at the epoch of reionization suggest a turnover in the abundance of faint galaxies at z ~ 6.

Abstract Background Increases in lipids have been observed in people with HIV (PWH) switching from tenofovir disoproxil fumarate (TDF) to tenofovir alafenamide (TAF). We assessed changes in low-density lipoprotein cholesterol (LDL-C) and triglycerides (TG) following a switch from TDF to TAF. Methods Adults with ≥1 lipid measure before and after switch from TDF to TAF were identified in the OPERA cohort. Multivariable linear regression using generalized estimating equations was used to estimate predicted changes in lipids over time on TAF, modeled flexibly with linear splines. Results A total of 6451 PWH switched from TDF to TAF, of whom 4328 maintained all other agents. LDL-C increased significantly by 1.40 mg/dL/mo over the first 3 months on TAF, by 0.33 mg/dL/mo between 3 and 9 months and then plateauing beyond 9 months. TG increased significantly by 3.52 mg/dL/mo over the first 3 months of TAF, by 0.91 mg/mL/mo between 3 and 9 months and by 0.72 mg/mL/mo between 9 and 16 months, but decreased thereafter. Similar patterns were observed in analyses restricted to PWH who switched from TDF to TAF but maintained all other agents. Conclusions TDF-to-TAF switch was associated with LDL-C and TG increases over the first 9 to 16 months on TAF. The dynamic patterns observed cannot be attributed to changes in other agents.

Background Two-drug regimens (2DRs) have been introduced in recent years to potentially reduce antiretroviral therapy (ART) toxicities and drug-drug interactions while demonstrating comparable efficacy to three-drug regimens (3DRs) for people with HIV (PWH). The objective of this study was to compare the real-world effectiveness and durability of a single-tablet 2DR of dolutegravir/lamivudine (DTG/3TC) with that of commonly prescribed 3DRs in ART-experienced, virologically suppressed PWH during the first 24 months of DTG/3TC availability in the United States. Methods Virologically suppressed (viral load [VL] < 200 copies/mL) adult PWH initiating DTG/3TC 2DR, bictegravir/emtricitabine/tenofovir alafenamide (BIC/FTC/TAF), or a DTG-based 3DR between 01MAY2019 and 31OCT2020 were identified in the OPERA ® cohort and followed through 30APR2021. Univariate Poisson regression (incidence rates) and marginal structural Cox proportional hazards models with inverse probability of treatment weights (hazard ratios) were used to quantify relationships between regimen type and confirmed virologic failure (2 consecutive VLs ≥ 200 copies/mL) or regimen discontinuation. Reasons for discontinuation were examined. Results A total of 8,037 ART-experienced, virologically suppressed PWH met the inclusion criteria and switched to DTG/3TC ( n  = 1,450), BIC/FTC/TAF ( n  = 5,691), or a DTG-based 3DR ( n  = 896). Incidence rates of confirmed virologic failure were low for all groups, at 0.66 (DTG/3TC), 0.84 (BIC/FTC/TAF), and 1.78 (DTG 3DR) per 100 person-years (py). Compared to DTG/3TC, only the DTG 3DRs were associated with a statistically significant increased hazard of confirmed virologic failure (hazard ratio: 5.21, 95% confidence interval: 1.85, 14.67). Discontinuation rates per 100 py were highest in the DTG 3DR group (24.90), followed by the DTG/3TC group (17.69) and the BIC/FTC/TAF group (8.30). Regardless of regimen, discontinuations were infrequently attributed to effectiveness (VL ≥ 200 copies/mL; 4%) or tolerability (adverse diagnoses, side effects, or lab abnormalities; 6%). Conclusions Among virologically suppressed PWH initiating a new regimen, few individuals experienced virologic failure in real-world clinical care. While rates of regimen discontinuation were high, most discontinuations could not be attributed to a lack of virologic control or poor tolerability. These findings suggest that DTG/3TC is an effective option for ART-experienced, virologically suppressed PWH.

Background HLA-B*57:01 screening was added to clinical care guidelines in 2008 to reduce the risk of hypersensitivity reaction from abacavir. The uptake of HLA-B*57:01 screening and incidence of hypersensitivity reaction were assessed in a prospective clinical cohort in the United States to evaluate the effectiveness of this intervention. Methods We included all patients initiating an abacavir-containing regimen for the first time in the pre-HLA-B*57:01 screening period (January 1, 1999 to June 14, 2008) or the post-HLA-B*57:01 screening period (June 15, 2008 to January 1, 2016). Yearly incidence of both HLA-B*57:01 screening and physician panel-adjudicated hypersensitivity reactions were calculated and compared. Results Of the 9619 patients eligible for the study, 33% initiated abacavir in the pre-screening period and 67% in the post-screening period. Incidence of HLA-B*57:01 screening prior to abacavir initiation increased from 43% in 2009 to 84% in 2015. The incidence of definite or probable hypersensitivity reactions decreased from 1.3% in the pre-screening period to 0.8% in 2009 and further to 0.2% in 2015 in the post-screening period. Conclusions Frequency of HLA-B*57:01 screening increased steadily since its first inclusion in treatment guidelines in the United States. This increase in screening was accompanied by a decreasing incidence of definite or probable hypersensitivity reactions over the same period. However, a considerable proportion of patients initiating abacavir were not screened, representing a failed opportunity to prevent hypersensitivity reactions. Where HLA-B*57:01 screening is standard of care, patients should be confirmed negative for this allele before starting abacavir treatment.

Background Weight gain has been associated with the use of antiretrovirals in people with HIV, especially with integrase inhibitors or tenofovir alafenamide, and among women. In 2018, doravirine became the latest non-nucleoside reverse transcriptase inhibitor to be approved in the US. We assessed changes in weight over time among virologically suppressed individuals who switched to a regimen containing doravirine (DOR). Methods From the US-based OPERA cohort, treatment-experienced adults with HIV who switched to a DOR-containing regimen between 30AUG2018-30NOV2022 with a viral load < 50 copies/mL were included (followed through 31MAY2023). The study population was characterized and a linear mixed model was used to estimate rates of weight change on DOR. Results were stratified by sex, by patterns of efavirenz (EFV) and/or tenofovir disoproxil fumarate (TDF) use before/after switch to DOR, and by integrase inhibitor (INSTI) & tenofovir alafenamide (TAF) use combination (restricted to individuals who maintained the same combination before/after switch). Results Of 388 included individuals, 21% were women, 33% were Black, and 78% were obese or overweight at DOR switch. Overall, people who switched to DOR lost an average of 0.80 kg/year (95% CI: -1.32, -0.28). Both women and men experienced statistically significant weight loss; women (70% Black, 70% aged ≥ 40 years) lost weight at a rate of -1.67 kg/year (95% CI: -3.32, -0.02) and men at a rate of -0.60 kg/year (95% CI: -1.12, -0.08). When EFV and TDF were absent before and after switch to DOR, statistically significant weight loss was observed. Among those who had the same INSTI and TAF combination throughout and had any INSTI or TAF use, a statistically non-significant trend toward weight loss was observed. Conclusions In one of the first real-world analyses of weight changes among virologically suppressed individuals who switched to a DOR-containing regimen in the US, DOR was associated with statistically significant weight loss. Patterns of use of other antiretrovirals did not fully explain the observed weight loss. These findings are clinically meaningful given that most individuals included were overweight or obese at switch to DOR and that women were predominantly of perimenopausal or menopausal age.

Cosmic rays are particles (mostly protons) accelerated to relativistic speeds. Despite wide agreement that supernova remnants (SNRs) are the sources of galactic cosmic rays, unequivocal evidence for the acceleration of protons in these objects is still lacking. When accelerated protons encounter interstellar material, they produce neutral pions, which in turn decay into gamma rays. This offers a compelling way to detect the acceleration sites of protons. The identification of pion-decay gamma rays has been difficult because high-energy electrons also produce gamma rays via bremsstrahlung and inverse Compton scattering. We detected the characteristic pion-decay feature in the gamma-ray spectra of two SNRs, IC 443 and W44, with the Fermi Large Area Telescope. This detection provides direct evidence that cosmic-ray protons are accelerated in SNRs.