Clinical sub-phenotypes of Staphylococcus aureus bacteraemia.

BACKGROUND: Staphylococcus aureus bacteraemia (SAB) is a clinically heterogeneous disease. The ability to identify sub-groups of patients with shared traits (sub-phenotypes) is an unmet need that could allow patient stratification for clinical management and research. We aimed to test the hypothesis that clinically-relevant sub-phenotypes can be reproducibly identified amongst patients with SAB. METHODS: We studied three cohorts of hospitalised adults with monomicrobial SAB: a UK retrospective observational study (Edinburgh cohort, n=458), the UK ARREST randomised trial (n=758), and the Spanish SAFO randomised trial (n=214). Latent class analysis was used to identify sub-phenotypes using routinely-collected clinical data, without considering outcomes. Mortality and microbiologic outcomes were then compared between sub-phenotypes. RESULTS: Included patients had predominantly methicillin-susceptible SAB (1366/1430,95.5%). We identified five distinct, reproducible clinical sub-phenotypes: (A) SAB associated with older age and comorbidity, (B) nosocomial intravenous catheter-associated SAB in younger people without comorbidity, (C) community-acquired metastatic SAB, (D) SAB associated with chronic kidney disease, and (E) SAB associated with injection drug use. Survival and microbiologic outcomes differed between the sub-phenotypes. 84-day mortality was highest in sub-phenotype A, and lowest in B and E. Microbiologic outcomes were worse in sub-phenotype C. In a secondary analysis of the ARREST trial, adjunctive rifampicin was associated with increased 84-day mortality in sub-phenotype B and improved microbiologic outcomes in sub-phenotype C. CONCLUSIONS: We have identified reproducible and clinically-relevant sub-phenotypes within SAB, and provide proof-of-principle of differential treatment effects. Through clinical trial enrichment and patient stratification, these sub-phenotypes could contribute to a personalised medicine approach to SAB.

When should factorial designs be used for late-phase randomised controlled trials?

BACKGROUND: A 2×2 factorial design evaluates two interventions (A versus control and B versus control) by randomising to control, A-only, B-only or both A and B together. Extended factorial designs are also possible (e.g. 3×3 or 2×2×2). Factorial designs often require fewer resources and participants than alternative randomised controlled trials, but they are not widely used. We identified several issues that investigators considering this design need to address, before they use it in a late-phase setting. METHODS: We surveyed journal articles published in 2000-2022 relating to designing factorial randomised controlled trials. We identified issues to consider based on these and our personal experiences. RESULTS: We identified clinical, practical, statistical and external issues that make factorial randomised controlled trials more desirable. Clinical issues are (1) interventions can be easily co-administered; (2) risk of safety issues from co-administration above individual risks of the separate interventions is low; (3) safety or efficacy data are wanted on the combination intervention; (4) potential for interaction (e.g. effect of A differing when B administered) is low; (5) it is important to compare interventions with other interventions balanced, rather than allowing randomised interventions to affect the choice of other interventions; (6) eligibility criteria for different interventions are similar. Practical issues are (7) recruitment is not harmed by testing many interventions; (8) each intervention and associated toxicities is unlikely to reduce either adherence to the other intervention or overall follow-up; (9) blinding is easy to implement or not required. Statistical issues are (10) a suitable scale of analysis can be identified; (11) adjustment for multiplicity is not required; (12) early stopping for efficacy or lack of benefit can be done effectively. External issues are (13) adequate funding is available and (14) the trial is not intended for licensing purposes. An overarching issue (15) is that factorial design should give a lower sample size requirement than alternative designs. Across designs with varying non-adherence, retention, intervention effects and interaction effects, 2×2 factorial designs require lower sample size than a three-arm alternative when one intervention effect is reduced by no more than 24%-48% in the presence of the other intervention compared with in the absence of the other intervention. CONCLUSIONS: Factorial designs are not widely used and should be considered more often using our issues to consider. Low potential for at most small to modest interaction is key, for example, where the interventions have different mechanisms of action or target different aspects of the disease being studied.

Pharmacokinetic Data of Dolutegravir in Second-line Treatment of Children With Human Immunodeficiency Virus: Results From the CHAPAS4 Trial.

BACKGROUND: Dolutegravir (DTG), combined with a backbone of 2 nucleoside reverse transcriptase inhibitors, is currently the preferred first-line treatment for human immunodeficiency virus (HIV) in childhood. CHAPAS4 is an ongoing randomized controlled trial investigating second-line treatment options for children with HIV. We did a nested pharmacokinetic (PK) substudy within CHAPAS4 to evaluate the DTG exposure in children with HIV taking DTG with food as part of their second-line treatment. METHODS: Additional consent was required for children on DTG enrolled in the CHAPAS4 trial to participate in this PK substudy. Children weighing 14-19.9 kg took 25 mg DTG as dispersible tablets and children ≥20 kg took 50 mg film-coated tablets. Steady-state 24-hour DTG plasma concentration-time PK profiling was done at t = 0 and 1, 2, 4, 6, 8, 12, and 24 hours after observed DTG intake with food. Reference adult PK data and pediatric data from the ODYSSEY trial were used primarily for comparison. The individual target trough concentration (Ctrough) was defined as 0.32 mg/L. RESULTS: Thirty-nine children on DTG were included in this PK substudy. The geometric mean (GM) area under the concentration-time curve over the dosing interval (AUC0-24h) was 57.1 hours × mg/L (coefficient of variation [CV%], 38.4%), which was approximately 8% below the average AUC0-24h in children in the ODYSSEY trial with comparable dosages, but above the adult reference. The GM (CV%) Ctrough was 0.82 mg/L (63.8%), which was comparable to ODYSSEY and adult reference values. CONCLUSIONS: This nested PK substudy shows that the exposure of DTG taken with food in children on second-line treatment is comparable with that of children in the ODYSSEY trial and adult references. Clinical Trials Registration.ISRCTN22964075.

First Pharmacokinetic Data of Tenofovir Alafenamide Fumarate and Tenofovir With Dolutegravir or Boosted Protease Inhibitors in African Children: A Substudy of the CHAPAS-4 Trial.

BACKGROUND: We evaluated the pharmacokinetics of tenofovir alafenamide fumarate (TAF) and tenofovir in a subset of African children enrolled in the CHAPAS-4 trial. METHODS: Children aged 3-15 years with human immunodeficiency virus infection failing first-line antiretroviral therapy were randomized to emtricitabine/TAF versus standard-of-care nucleoside reverse transcriptase inhibitor combination, plus dolutegravir, atazanavir/ritonavir, darunavir/ritonavir, or lopinavir/ritonavir. Daily emtricitabine/TAF was dosed according to World Health Organization (WHO)-recommended weight bands: 120/15 mg in children weighing 14 to <25 kg and 200/25 mg in those weighing ≥25 kg. At steady state, 8-9 blood samples were taken to construct pharmacokinetic curves. Geometric mean (GM) area under the concentration-time curve (AUC) and the maximum concentration (Cmax) were calculated for TAF and tenofovir and compared to reference exposures in adults. RESULTS: Pharmacokinetic results from 104 children taking TAF were analyzed. GM (coefficient of variation [CV%]) TAF AUClast when combined with dolutegravir (n = 18), darunavir/ritonavir (n = 34), or lopinavir/ritonavir (n = 20) were 284.5 (79), 232.0 (61), and 210.2 (98) ng*hour/mL, respectively, and were comparable to adult reference values. When combined with atazanavir/ritonavir (n = 32), TAF AUClast increased to 511.4 (68) ng*hour/mL. For each combination, tenofovir GM (CV%) AUCtau and Cmax remained below reference values in adults taking 25 mg TAF with a boosted protease inhibitors. CONCLUSIONS: In children, TAF combined with boosted PIs or dolutegravir and dosed according to WHO-recommended weight bands provides TAF and tenofovir concentrations previously demonstrated to be well tolerated and effective in adults. These data provide the first evidence for use of these combinations in African children. CLINICAL TRIALS REGISTRATION: ISRCTN22964075.

Safety and immunogenicity of a self-amplifying RNA vaccine against COVID-19: COVAC1, a phase I, dose-ranging trial.

BACKGROUND: Lipid nanoparticle (LNP) encapsulated self-amplifying RNA (saRNA) is a novel technology formulated as a low dose vaccine against COVID-19. METHODS: A phase I first-in-human dose-ranging trial of a saRNA COVID-19 vaccine candidate LNP-nCoVsaRNA, was conducted at Imperial Clinical Research Facility, and participating centres in London, UK, between 19th June to 28th October 2020. Participants received two intramuscular (IM) injections of LNP-nCoVsaRNA at six different dose levels, 0.1-10.0µg, given four weeks apart. An open-label dose escalation was followed by a dose evaluation. Solicited adverse events (AEs) were collected for one week from enrolment, with follow-up at regular intervals (1-8 weeks). The binding and neutralisation capacity of anti-SARS-CoV-2 antibody raised in participant sera was measured by means of an anti-Spike (S) IgG ELISA, immunoblot, SARS-CoV-2 pseudoneutralisation and wild type neutralisation assays. (The trial is registered: ISRCTN17072692, EudraCT 2020-001646-20). FINDINGS: 192 healthy individuals with no history or serological evidence of COVID-19, aged 18-45 years were enrolled. The vaccine was well tolerated with no serious adverse events related to vaccination. Seroconversion at week six whether measured by ELISA or immunoblot was related to dose (both p<0.001), ranging from 8% (3/39; 0.1µg) to 61% (14/23; 10.0µg) in ELISA and 46% (18/39; 0.3µg) to 87% (20/23; 5.0µg and 10.0µg) in a post-hoc immunoblot assay. Geometric mean (GM) anti-S IgG concentrations ranged from 74 (95% CI, 45-119) at 0.1µg to 1023 (468-2236) ng/mL at 5.0µg (p<0.001) and was not higher at 10.0µg. Neutralisation of SARS-CoV-2 by participant sera was measurable in 15% (6/39; 0.1µg) to 48% (11/23; 5.0µg) depending on dose level received. INTERPRETATION: Encapsulated saRNA is safe for clinical development, is immunogenic at low dose levels but failed to induce 100% seroconversion. Modifications to optimise humoral responses are required to realise its potential as an effective vaccine against SARS-CoV-2. FUNDING: This study was co-funded by grants and gifts from the Medical Research Council UKRI (MC_PC_19076), and the National Institute Health Research/Vaccine Task Force, Partners of Citadel and Citadel Securities, Sir Joseph Hotung Charitable Settlement, Jon Moulton Charity Trust, Pierre Andurand, Restore the Earth.

The impact of viraemia on inflammatory biomarkers and CD4+ cell subpopulations in HIV-infected children in sub-Saharan Africa.

OBJECTIVE: To determine the impact of virological control on inflammation and cluster of differentiation 4 depletion among HIV-infected children initiating antiretroviral therapy (ART) in sub-Saharan Africa. DESIGN: Longitudinal cohort study. METHODS: In a sub-study of the ARROW trial (ISRCTN24791884), we measured longitudinal HIV viral loads, inflammatory biomarkers (C-reactive protein, tumour necrosis factor alpha, interleukin 6 (IL-6), soluble CD14) and (Uganda only) whole blood immunophenotype by flow cytometry in 311 Zimbabwean and Ugandan children followed for median 3.5 years on first-line ART. We classified each viral load measurement as consistent suppression, blip/post-blip, persistent low-level viral load or rebound. We used multi-level models to estimate rates of increase or decrease in laboratory markers, and Poisson regression to estimate the incidence of clinical events. RESULTS: Overall, 42% children experienced viral blips, but these had no significant impact on immune reconstitution or inflammation. Persistent detectable viraemia occurred in one-third of children and prevented further immune reconstitution, but had little impact on inflammatory biomarkers. Virological rebound to ≥5000 copies/ml was associated with arrested immune reconstitution, rising IL-6 and increased risk of clinical disease progression. CONCLUSIONS: As viral load testing becomes more available in sub-Saharan Africa, repeat testing algorithms will be required to identify those with virological rebound, who need switching to prevent disease progression, whilst preventing unnecessary second-line regimen initiation in the majority of children with detectable viraemia who remain at low risk of disease progression.

Predictors of recurrence, early treatment failure and death from Staphylococcus aureus bacteraemia: Observational analyses within the ARREST trial.

OBJECTIVES: Adjunctive rifampicin did not reduce failure/recurrence/death as a composite endpoint in the ARREST trial of Staphylococcus aureus bacteraemia, but did reduce recurrences. We investigated clinically-defined 14-day treatment failure, and recurrence and S. aureus-attributed/unattributed mortality by 12-weeks to further define their predictors. METHODS: A post-hoc exploratory analysis using competing risks models was conducted to identify sub-groups which might benefit from rifampicin. A points-based recurrence risk score was developed and used to compare rifampicin's benefits. RESULTS: Recurrence was strongly associated with liver and renal failure, diabetes and immune-suppressive drugs (p < 0.005); in contrast, failure and S. aureus-attributed mortality were associated with older age and higher neutrophil counts. Higher SOFA scores predicted mortality; higher Charlson scores and deep-seated initial infection focus predicted failure. Unexpectedly, recurrence risk increased with increasing BMI in placebo (p = 0.04) but not rifampicin (p = 0.60) participants (pheterogeneity = 0.06). A persistent focus was judged the primary reason for recurrence in 23(74%). A 5-factor risk score based on BMI, Immunosuppression, Renal disease, Diabetes, Liver disease (BIRDL) strongly predicted recurrence (p < 0.001). CONCLUSIONS: Rifampicin reduces recurrences overall; those with greatest absolute risk reductions were identified using a simple risk score. Source control and adequate duration of antibiotic therapy remain essential to prevent recurrence and improve outcomes.

Inflammatory biomarkers in HIV-infected children hospitalized for severe malnutrition in Uganda and Zimbabwe.

OBJECTIVES: A proportion of HIV-infected children with advanced disease develop severe malnutrition soon after antiretroviral therapy (ART) initiation. We tested the hypothesis that systemic inflammation underlies the pathogenesis of severe malnutrition in HIV-infected children. DESIGN: Cross-sectional laboratory substudy in 613 HIV-infected children initiating ART in Uganda and Zimbabwe. METHODS: We measured C-reactive protein (CRP), TNFα, IL-6 and soluble CD14 by ELISA in cryopreserved plasma at baseline (pre-ART) and week-4 (children with severe malnutrition only). Independent associations between baseline biomarkers and subsequent hospitalization for severe malnutrition were identified using multivariable fractional polynomial logistic regression. RESULTS: Compared with children without severe malnutrition (n = 574, median age 6.3 years, median baseline weight-for-age Z-score -2.2), children hospitalized for severe malnutrition post-ART (n = 39, median age 2.3 years, median baseline weight-for-age Z-score -4.8) had higher baseline CRP [median 13.5 (interquartile range 5.5, 41.1) versus 4.1 (1.4, 14.4) mg/l; P = 0.003] and IL-6 [median 9.2 (6.7, 15.6) versus 5.9 (4.6, 9.3) pg/ml; P < 0.0001], but similar overall TNFα, soluble CD14 and HIV viral load (all P > 0.06). In a multivariable model, higher pre-ART IL-6, lower TNFα and lower weight-for-age were independently associated with subsequent hospitalization for severe malnutrition. Between weeks 0 and 4, there was a significant rise in CRP, IL-6 and soluble CD14, and fall in TNFα and HIV viral load in children hospitalized for severe malnutrition (all P < 0.02). CONCLUSION: Pre-ART IL-6 and TNFα were more strongly associated with hospitalization for severe malnutrition than CD4 cell count or viral load, highlighting the importance of inflammation at the time of ART initiation in HIV-infected children.

Cotrimoxazole reduces systemic inflammation in HIV infection by altering the gut microbiome and immune activation.

Long-term cotrimoxazole prophylaxis reduces mortality and morbidity in HIV infection, but the mechanisms underlying these clinical benefits are unclear. Here, we investigate the impact of cotrimoxazole on systemic inflammation, an independent driver of HIV mortality. In HIV-positive Ugandan and Zimbabwean children receiving antiretroviral therapy, we show that plasma inflammatory markers were lower after randomization to continue (n = 144) versus stop (n = 149) cotrimoxazole. This was not explained by clinical illness, HIV progression, or nutritional status. Because subclinical enteropathogen carriage and enteropathy can drive systemic inflammation, we explored cotrimoxazole effects on the gut microbiome and intestinal inflammatory biomarkers. Although global microbiome composition was unchanged, viridans group Streptococci and streptococcal mevalonate pathway enzymes were lower among children continuing (n = 36) versus stopping (n = 36) cotrimoxazole. These changes were associated with lower fecal myeloperoxidase. To isolate direct effects of cotrimoxazole on immune activation from antibiotic effects, we established in vitro models of systemic and intestinal inflammation. In vitro cotrimoxazole had modest but consistent inhibitory effects on proinflammatory cytokine production by blood leukocytes from HIV-positive (n = 16) and HIV-negative (n = 8) UK adults and reduced IL-8 production by gut epithelial cell lines. Collectively we demonstrate that cotrimoxazole reduces systemic and intestinal inflammation both indirectly via antibiotic effects on the microbiome and directly by blunting immune and epithelial cell activation. Synergy between these pathways may explain the clinical benefits of cotrimoxazole despite high antimicrobial resistance, providing further rationale for extending coverage among people living with HIV in sub-Saharan Africa.

Raltegravir-intensified initial antiretroviral therapy in advanced HIV disease in Africa: A randomised controlled trial.

BACKGROUND: In sub-Saharan Africa, individuals infected with HIV who are severely immunocompromised have high mortality (about 10%) shortly after starting antiretroviral therapy (ART). This group also has the greatest risk of morbidity and mortality associated with immune reconstitution inflammatory syndrome (IRIS), a paradoxical response to successful ART. Integrase inhibitors lead to significantly more rapid declines in HIV viral load (VL) than all other ART classes. We hypothesised that intensifying standard triple-drug ART with the integrase inhibitor, raltegravir, would reduce HIV VL faster and hence reduce early mortality, although this strategy could also risk more IRIS events. METHODS AND FINDINGS: In a 2×2×2 factorial open-label parallel-group trial, treatment-naive adults, adolescents, and children >5 years old infected with HIV, with cluster of differentiation 4 (CD4) <100 cells/mm3, from eight urban/peri-urban HIV clinics at regional hospitals in Kenya, Malawi, Uganda, and Zimbabwe were randomised 1:1 to initiate standard triple-drug ART, with or without 12-week raltegravir intensification, and followed for 48 weeks. The primary outcome was 24-week mortality, analysed by intention to treat. Of 2,356 individuals screened for eligibility, 1,805 were randomised between 18 June 2013 and 10 April 2015. Of the 1,805 participants, 961 (53.2%) were male, 72 (4.0%) were children/adolescents, median age was 36 years, CD4 count was 37 cells/mm3, and plasma viraemia was 249,770 copies/mL. Fifty-six participants (3.1%) were lost to follow-up at 48 weeks. By 24 weeks, 97/902 (10.9%) raltegravir-intensified ART versus 91/903 (10.2%) standard ART participants had died (adjusted hazard ratio [aHR] = 1.10 [95% CI 0.82-1.46], p = 0.53), with no evidence of interaction with other randomisations (pheterogeneity > 0.7) and despite significantly greater VL suppression with raltegravir-intensified ART at 4 weeks (343/836 [41.0%] versus 113/841 [13.4%] with standard ART, p < 0.001) and 12 weeks (567/789 [71.9%] versus 415/803 [51.7%] with standard ART, p < 0.001). Through 48 weeks, there was no evidence of differences in mortality (aHR = 0.98 [95% CI 0.76-1.28], p = 0.91); in serious (aHR = 0.99 [0.81-1.21], p = 0.88), grade-4 (aHR = 0.88 [0.71-1.09], p = 0.29), or ART-modifying (aHR = 0.90 [0.63-1.27], p = 0.54) adverse events (the latter occurring in 59 [6.5%] participants with raltegravir-intensified ART versus 66 [7.3%] with standard ART); in events judged compatible with IRIS (occurring in 89 [9.9%] participants with raltegravir-intensified ART versus 86 [9.5%] with standard ART, p = 0.79) or in hospitalisations (aHR = 0.94 [95% CI 0.76-1.17], p = 0.59). At 12 weeks, one and two raltegravir-intensified participants had predicted intermediate-level and high-level raltegravir resistance, respectively. At 48 weeks, the nucleoside reverse transcriptase inhibitor (NRTI) mutation K219E/Q (p = 0.004) and the non-nucleoside reverse transcriptase inhibitor (NNRTI) mutations K101E/P (p = 0.03) and P225H (p = 0.007) were less common in virus from participants with raltegravir-intensified ART, with weak evidence of less intermediate- or high-level resistance to tenofovir (p = 0.06), abacavir (p = 0.08), and rilpivirine (p = 0.07). Limitations of the study include limited clinical, radiological, and/or microbiological information for some participants, reflecting available services at the centres, and lack of baseline genotypes. CONCLUSIONS: Although 12 weeks of raltegravir intensification was well tolerated and reduced HIV viraemia significantly faster than standard triple-drug ART during the time of greatest risk for early death, this strategy did not reduce mortality or clinical events in this group and is not warranted. There was no excess of IRIS-compatible events, suggesting that integrase inhibitors can be used safely as part of standard triple-drug first-line therapy in severely immunocompromised individuals. TRIAL REGISTRATION: ClinicalTrials.gov NCT01825031. TRIAL REGISTRATION: International Standard Randomised Controlled Trials Number ISRCTN 43622374.

Adjunctive rifampicin to reduce early mortality from Staphylococcus aureus bacteraemia: the ARREST RCT.

BACKGROUND: Staphylococcus aureus bacteraemia is a common and frequently fatal infection. Adjunctive rifampicin may enhance early S. aureus killing, sterilise infected foci and blood faster, and thereby reduce the risk of dissemination, metastatic infection and death. OBJECTIVES: To determine whether or not adjunctive rifampicin reduces bacteriological (microbiologically confirmed) failure/recurrence or death through 12 weeks from randomisation. Secondary objectives included evaluating the impact of rifampicin on all-cause mortality, clinically defined failure/recurrence or death, toxicity, resistance emergence, and duration of bacteraemia; and assessing the cost-effectiveness of rifampicin. DESIGN: Parallel-group, randomised (1 : 1), blinded, placebo-controlled multicentre trial. SETTING: UK NHS trust hospitals. PARTICIPANTS: Adult inpatients (≥ 18 years) with meticillin-resistant or susceptible S. aureus grown from one or more blood cultures, who had received < 96 hours of antibiotic therapy for the current infection, and without contraindications to rifampicin. INTERVENTIONS: Adjunctive rifampicin (600-900 mg/day, oral or intravenous) or placebo for 14 days in addition to standard antibiotic therapy. Investigators and patients were blinded to trial treatment. Follow-up was for 12 weeks (assessments at 3, 7, 10 and 14 days, weekly until discharge and final assessment at 12 weeks post randomisation). MAIN OUTCOME MEASURES: The primary outcome was all-cause bacteriological (microbiologically confirmed) failure/recurrence or death through 12 weeks from randomisation. RESULTS: Between December 2012 and October 2016, 758 eligible participants from 29 UK hospitals were randomised: 370 to rifampicin and 388 to placebo. The median age was 65 years [interquartile range (IQR) 50-76 years]. A total of 485 (64.0%) infections were community acquired and 132 (17.4%) were nosocomial; 47 (6.2%) were caused by meticillin-resistant S. aureus. A total of 301 (39.7%) participants had an initial deep infection focus. Standard antibiotics were given for a median of 29 days (IQR 18-45 days) and 619 (81.7%) participants received flucloxacillin. By 12 weeks, 62 out of 370 (16.8%) patients taking rifampicin versus 71 out of 388 (18.3%) participants taking the placebo experienced bacteriological (microbiologically confirmed) failure/recurrence or died [absolute risk difference -1.4%, 95% confidence interval (CI) -7.0% to 4.3%; hazard ratio 0.96, 95% CI 0.68 to 1.35; p = 0.81]. There were 4 (1.1%) and 5 (1.3%) bacteriological failures (p = 0.82) in the rifampicin and placebo groups, respectively. There were 3 (0.8%) versus 16 (4.1%) bacteriological recurrences (p = 0.01), and 55 (14.9%) versus 50 (12.9%) deaths without bacteriological failure/recurrence (p = 0.30) in the rifampicin and placebo groups, respectively. Over 12 weeks, there was no evidence of differences in clinically defined failure/recurrence/death (p = 0.84), all-cause mortality (p = 0.60), serious (p = 0.17) or grade 3/4 (p = 0.36) adverse events (AEs). However, 63 (17.0%) participants in the rifampicin group versus 39 (10.1%) participants in the placebo group experienced antibiotic or trial drug-modifying AEs (p = 0.004), and 24 (6.5%) participants in the rifampicin group versus 6 (1.5%) participants in the placebo group experienced drug-interactions (p = 0.0005). Evaluation of the costs and health-related quality-of-life impacts revealed that an episode of S. aureus bacteraemia costs an average of £12,197 over 12 weeks. Rifampicin was estimated to save 10% of episode costs (p = 0.14). After adjustment, the effect of rifampicin on total quality-adjusted life-years (QALYs) was positive (0.004 QALYs), but not statistically significant (standard error 0.004 QALYs). CONCLUSIONS: Adjunctive rifampicin provided no overall benefit over standard antibiotic therapy in adults with S. aureus bacteraemia. FUTURE WORK: Given the substantial mortality, other antibiotic combinations or improved source management should be investigated. TRIAL REGISTRATIONS: Current Controlled Trials ISRCTN37666216, EudraCT 2012-000344-10 and Clinical Trials Authorisation 00316/0243/001. FUNDING: This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 22, No. 59. See the NIHR Journals Library website for further project information.

Effect of ready-to-use supplementary food on mortality in severely immunocompromised HIV-infected individuals in Africa initiating antiretroviral therapy (REALITY): an open-label, parallel-group, randomised controlled trial.

BACKGROUND: In sub-Saharan Africa, severely immunocompromised HIV-infected individuals have a high risk of mortality during the first few months after starting antiretroviral therapy (ART). We hypothesise that universally providing ready-to-use supplementary food (RUSF) would increase early weight gain, thereby reducing early mortality compared with current guidelines recommending ready-to-use therapeutic food (RUTF) for severely malnourished individuals only. METHODS: We did a 2 × 2 × 2 factorial, open-label, parallel-group trial at inpatient and outpatient facilities in eight urban or periurban regional hospitals in Kenya, Malawi, Uganda, and Zimbabwe. Eligible participants were ART-naive adults and children aged at least 5 years with confirmed HIV infection and a CD4 cell count of fewer than 100 cells per µL, who were initiating ART at the facilities. We randomly assigned participants (1:1) to initiate ART either with (RUSF) or without (no-RUSF) 12 weeks' of peanut-based RUSF containing 1000 kcal per day and micronutrients, given as two 92 g packets per day for adults and one packet (500 kcal per day) for children aged 5-12 years, regardless of nutritional status. In both groups, individuals received supplementation with RUTF only when severely malnourished (ie, body-mass index [BMI] <16-18 kg/m2 or BMI-for-age Z scores <-3 for children). We did the randomisation with computer-generated, sequentially numbered tables with different block sizes incorporated within an online database. Randomisation was stratified by centre, age, and two other factorial randomisations, to 12 week adjunctive raltegravir and enhanced anti-infection prophylaxis (reported elsewhere). Clinic visits were scheduled at weeks 2, 4, 8, 12, 18, 24, 36, and 48, and included nurse assessment of vital status and symptoms and dispensing of all medication including ART and RUSF. The primary outcome was mortality at week 24, analysed by intention to treat. Secondary outcomes included absolute changes in weight, BMI, and mid-upper-arm circumference (MUAC). Safety was analysed in all randomly assigned participants. Follow-up was 48 weeks. This trial is registered with ClinicalTrials.gov (NCT01825031) and the ISRCTN registry (43622374). FINDINGS: Between June 18, 2013, and April 10, 2015, we randomly assigned 1805 participants to treatment: 897 to RUSF and 908 to no-RUSF. 56 (3%) were lost-to-follow-up. 96 (10·9%, 95% CI 9·0-13·1) participants allocated to RUSF and 92 (10·3%, 8·5-12·5) to no-RUSF died within 24 weeks (hazard ratio 1·05, 95% CI 0·79-1·40; log-rank p=0·75), with no evidence of interaction with the other randomisations (both p>0·7). Through 48 weeks, adults and adolescents aged 13 years and older in the RUSF group had significantly greater gains in weight, BMI, and MUAC than the no-RUSF group (p=0·004, 0·004, and 0·03, respectively). The most common type of serious adverse event was specific infections, occurring in 90 (10%) of 897 participants assigned RUSF and 87 (10%) of 908 assigned no-RUSF. By week 48, 205 participants had serious adverse events in both groups (p=0·81), and 181 had grade 4 adverse events in the RUSF group compared with 172 in the non-RUSF group (p=0·45). INTERPRETATION: In severely immunocompromised HIV-infected individuals, providing RUSF universally at ART initiation, compared with providing RUTF to severely malnourished individuals only, improved short-term weight gain but not mortality. A change in policy to provide nutritional supplementation to all severely immunocompromised HIV-infected individuals starting ART is therefore not warranted at present. FUNDING: Joint Global Health Trials Scheme (UK Medical Research Council, UK Department for International Development, and Wellcome Trust).

Causes and Timing of Mortality and Morbidity Among Late Presenters Starting Antiretroviral Therapy in the REALITY Trial.

Background: In sub-Saharan Africa, 20%-25% of people starting antiretroviral therapy (ART) have severe immunosuppression; approximately 10% die within 3 months. In the Reduction of EArly mortaLITY (REALITY) randomized trial, a broad enhanced anti-infection prophylaxis bundle reduced mortality vs cotrimoxazole. We investigate the contribution and timing of different causes of mortality/morbidity. Methods: Participants started ART with a CD4 count <100 cells/µL; enhanced prophylaxis comprised cotrimoxazole plus 12 weeks of isoniazid + fluconazole, single-dose albendazole, and 5 days of azithromycin. A blinded committee adjudicated events and causes of death as (non-mutually exclusively) tuberculosis, cryptococcosis, severe bacterial infection (SBI), other potentially azithromycin-responsive infections, other events, and unknown. Results: Median pre-ART CD4 count was 37 cells/µL. Among 1805 participants, 225 (12.7%) died by week 48. Fatal/nonfatal events occurred early (median 4 weeks); rates then declined exponentially. One hundred fifty-four deaths had single and 71 had multiple causes, including tuberculosis in 4.5% participants, cryptococcosis in 1.1%, SBI in 1.9%, other potentially azithromycin-responsive infections in 1.3%, other events in 3.6%, and unknown in 5.0%. Enhanced prophylaxis reduced deaths from cryptococcosis and unknown causes (P < .05) but not tuberculosis, SBI, potentially azithromycin-responsive infections, or other causes (P > .3); and reduced nonfatal/fatal tuberculosis and cryptococcosis (P < .05), but not SBI, other potentially azithromycin-responsive infections, or other events (P > .2). Conclusions: Enhanced prophylaxis reduced mortality from cryptococcosis and unknown causes and nonfatal tuberculosis and cryptococcosis. High early incidence of fatal/nonfatal events highlights the need for starting enhanced-prophylaxis with ART in advanced disease. Clinical Trials Registration: ISRCTN43622374.

Adjunctive rifampicin for Staphylococcus aureus bacteraemia (ARREST): a multicentre, randomised, double-blind, placebo-controlled trial.

BACKGROUND: Staphylococcus aureus bacteraemia is a common cause of severe community-acquired and hospital-acquired infection worldwide. We tested the hypothesis that adjunctive rifampicin would reduce bacteriologically confirmed treatment failure or disease recurrence, or death, by enhancing early S aureus killing, sterilising infected foci and blood faster, and reducing risks of dissemination and metastatic infection. METHODS: In this multicentre, randomised, double-blind, placebo-controlled trial, adults (≥18 years) with S aureus bacteraemia who had received ≤96 h of active antibiotic therapy were recruited from 29 UK hospitals. Patients were randomly assigned (1:1) via a computer-generated sequential randomisation list to receive 2 weeks of adjunctive rifampicin (600 mg or 900 mg per day according to weight, oral or intravenous) versus identical placebo, together with standard antibiotic therapy. Randomisation was stratified by centre. Patients, investigators, and those caring for the patients were masked to group allocation. The primary outcome was time to bacteriologically confirmed treatment failure or disease recurrence, or death (all-cause), from randomisation to 12 weeks, adjudicated by an independent review committee masked to the treatment. Analysis was intention to treat. This trial was registered, number ISRCTN37666216, and is closed to new participants. FINDINGS: Between Dec 10, 2012, and Oct 25, 2016, 758 eligible participants were randomly assigned: 370 to rifampicin and 388 to placebo. 485 (64%) participants had community-acquired S aureus infections, and 132 (17%) had nosocomial S aureus infections. 47 (6%) had meticillin-resistant infections. 301 (40%) participants had an initial deep infection focus. Standard antibiotics were given for 29 (IQR 18-45) days; 619 (82%) participants received flucloxacillin. By week 12, 62 (17%) of participants who received rifampicin versus 71 (18%) who received placebo experienced treatment failure or disease recurrence, or died (absolute risk difference -1·4%, 95% CI -7·0 to 4·3; hazard ratio 0·96, 0·68-1·35, p=0·81). From randomisation to 12 weeks, no evidence of differences in serious (p=0·17) or grade 3-4 (p=0·36) adverse events were observed; however, 63 (17%) participants in the rifampicin group versus 39 (10%) in the placebo group had antibiotic or trial drug-modifying adverse events (p=0·004), and 24 (6%) versus six (2%) had drug interactions (p=0·0005). INTERPRETATION: Adjunctive rifampicin provided no overall benefit over standard antibiotic therapy in adults with S aureus bacteraemia. FUNDING: UK National Institute for Health Research Health Technology Assessment.

Virological response and resistance among HIV-infected children receiving long-term antiretroviral therapy without virological monitoring in Uganda and Zimbabwe: Observational analyses within the randomised ARROW trial.

BACKGROUND: Although WHO recommends viral load (VL) monitoring for those on antiretroviral therapy (ART), availability in low-income countries remains limited. We investigated long-term VL and resistance in HIV-infected children managed without real-time VL monitoring. METHODS AND FINDINGS: In the ARROW factorial trial, 1,206 children initiating ART in Uganda and Zimbabwe between 15 March 2007 and 18 November 2008, aged a median 6 years old, with median CD4% of 12%, were randomised to monitoring with or without 12-weekly CD4 counts and to receive 2 nucleoside reverse transcriptase inhibitors (2NRTI, mainly abacavir+lamivudine) with a non-nucleoside reverse transcriptase inhibitor (NNRTI) or 3 NRTIs as long-term ART. All children had VL assayed retrospectively after a median of 4 years on ART; those with >1,000 copies/ml were genotyped. Three hundred and sixteen children had VL and genotypes assayed longitudinally (at least every 24 weeks). Overall, 67 (6%) switched to second-line ART and 54 (4%) died. In children randomised to WHO-recommended 2NRTI+NNRTI long-term ART, 308/378 (81%) monitored with CD4 counts versus 297/375 (79%) without had VL <1,000 copies/ml at 4 years (difference = +2.3% [95% CI -3.4% to +8.0%]; P = 0.43), with no evidence of differences in intermediate/high-level resistance to 11 drugs. Among children with longitudinal VLs, only 5% of child-time post-week 24 was spent with persistent low-level viraemia (80-5,000 copies/ml) and 10% with VL rebound ≥5,000 copies/ml. No child resuppressed <80 copies/ml after confirmed VL rebound ≥5,000 copies/ml. A median of 1.0 (IQR 0.0,1.5) additional NRTI mutation accumulated over 2 years' rebound. Nineteen out of 48 (40%) VLs 1,000-5,000 copies/ml were immediately followed by resuppression <1,000 copies/ml, but only 17/155 (11%) VLs ≥5,000 copies/ml resuppressed (P < 0.0001). Main study limitations are that analyses were exploratory and treatment initiation used 2006 criteria, without pre-ART genotypes. CONCLUSIONS: In this study, children receiving first-line ART in sub-Saharan Africa without real-time VL monitoring had good virological and resistance outcomes over 4 years, regardless of CD4 monitoring strategy. Many children with detectable low-level viraemia spontaneously resuppressed, highlighting the importance of confirming virological failure before switching to second-line therapy. Children experiencing rebound ≥5,000 copies/ml were much less likely to resuppress, but NRTI resistance increased only slowly. These results are relevant to the increasing numbers of HIV-infected children receiving first-line ART in sub-Saharan Africa with limited access to virological monitoring. TRIAL REGISTRATION: ISRCTN Registry, ISRCTN24791884.

Virologic Response to First-line Efavirenz- or Nevirapine-based Antiretroviral Therapy in HIV-infected African Children.

BACKGROUND: Poorer virologic response to nevirapine- versus efavirenz-based antiretroviral therapy (ART) has been reported in adult systematic reviews and pediatric studies. METHODS: We compared drug discontinuation and viral load (VL) response in ART-naïve Ugandan/Zimbabwean children ≥3 years of age initiating ART with clinician-chosen nevirapine versus efavirenz in the ARROW trial. Predictors of suppression <80, <400 and <1000 copies/mL at 36, 48 and 144 weeks were identified using multivariable logistic regression with backwards elimination (P = 0.1). RESULTS: A total of 445 (53%) children received efavirenz and 391 (47%) nevirapine. Children receiving efavirenz were older (median age, 8.6 vs. 7.5 years nevirapine, P < 0.001) and had higher CD4% (12% vs. 10%, P = 0.05), but similar pre-ART VL (P = 0.17). The initial non-nucleoside-reverse-transcriptase-inhibitor (NNRTI) was permanently discontinued for adverse events in 7 of 445 (2%) children initiating efavirenz versus 9 of 391 (2%) initiating nevirapine (P = 0.46); at switch to second line in 17 versus 23, for tuberculosis in 0 versus 26, for pregnancy in 6 versus 0 and for other reasons in 15 versus 5. Early (36-48 weeks) virologic suppression <80 copies/mL was superior with efavirenz, particularly in children with higher pre-ART VL (P = 0.0004); longer-term suppression was superior with nevirapine in older children (P = 0.05). Early suppression was poorer in the youngest and oldest children, regardless of NNRTI (P = 0.02); longer-term suppression was poorer in those with higher pre-ART VL regardless of NNRTI (P = 0.05). Results were broadly similar for <400 and <1000 copies/mL. CONCLUSION: Short-term VL suppression favored efavirenz, but long-term relative performance was age dependent, with better suppression in older children with nevirapine, supporting World Health Organization recommendation that nevirapine remains an alternative NNRTI.

Baseline Inflammatory Biomarkers Identify Subgroups of HIV-Infected African Children With Differing Responses to Antiretroviral Therapy.

BACKGROUND: Identifying determinants of morbidity and mortality may help target future interventions for human immunodeficiency virus (HIV)-infected children. METHODS: CD4(+) T-cell count, HIV viral load, and levels of biomarkers (C-reactive protein, tumor necrosis factor α [TNF-α], interleukin 6 [IL-6], and soluble CD14) and interleukin 7 were measured at antiretroviral therapy (ART) initiation in the ARROW trial (case-cohort design). Cases were individuals who died, had new or recurrent World Health Organization clinical stage 4 events, or had poor immunological response to ART. RESULTS: There were 115 cases (54 died, 45 had World Health Organization clinical stage 4 events, and 49 had poor immunological response) and 485 controls. Before ART initiation, the median ages of cases and controls were 8.2 years (interquartile range [IQR], 4.4-11.4 years) and 5.8 years (IQR, 2.3-9.3 years), respectively, and the median percentages of lymphocytes expressing CD4 were 4% (IQR, 1%-9%) and 13% (IQR, 8%-18%), respectively. In multivariable logistic regression, cases had lower age-associated CD4(+) T-cell count ratio (calculated as the ratio of the subject's CD4(+) T-cell count to the count expected in healthy individuals of the same age; P < .0001) and higher IL-6 level (P = .002) than controls. Clustering biomarkers and age-associated CD4(+) and CD8(+) T-cell count ratios identified 4 groups of children. Group 1 had the highest frequency of cases (41% cases; 16% died) and profound immunosuppression; group 2 had similar mortality (23% cases; 15% died), but children were younger, with less profound immunosuppression and high levels of inflammatory biomarkers and malnutrition; group 3 comprised young children with moderate immunosuppression, high TNF-α levels, and high age-associated CD8(+) T-cell count ratios but lower frequencies of events (12% cases; 7% died); and group 4 comprised older children with low inflammatory biomarker levels, lower HIV viral loads, and good clinical outcomes (11% cases; 5% died). CONCLUSIONS: While immunosuppression is the major determinant of poor outcomes during ART, baseline inflammation is an additional important factor, identifying a subgroup of young children with similar mortality. Antiinflammatory interventions may help improve outcomes.

Single-dose nevirapine exposure does not affect response to antiretroviral therapy in HIV-infected African children aged below 3 years.

OBJECTIVES: To assess the impact of exposure to single-dose nevirapine (sdNVP) on virological response in young Ugandan/Zimbabwean children (<3 years) initiating antiretroviral therapy (ART), and to investigate other predictors of response. DESIGN: Observational analysis within the ARROW randomized trial. METHODS: sdNVP exposure was ascertained by the caregiver's self-report when the child initiated non-nucleoside reverse transcriptase inhibitor (NNRTI)-based ART. Viral load was assayed retrospectively over a median 4.1 years of follow-up. Multivariable logistic regression models were used to identify independent predictors of viral load below 80 copies/ml, 48 and 144 weeks after ART initiation (backwards elimination, exit P = 0.1). RESULTS: Median (IQR) age at ART initiation was 17 (10-23) months in 78 sdNVP-exposed children vs. 21 (14-27) months in 289 non-exposed children (36 vs. 20% <12 months). At week 48, 49 of 73 (67%) sdNVP-exposed and 154 of 272 (57%) non-exposed children had viral load below 80 copies/ml [adjusted odds ratio (aOR) 2.34 (1.26-4.34), P = 0.007]; 79 and 77% had viral load below 400 copies/ml. Suppression was significantly lower in males (P = 0.009), those with higher pre-ART viral load (P = 0.001), taking syrups (P = 0.05) and with lower self-reported adherence (P = 0.04). At week 144, 55 of 73 (75%) exposed and 188 of 272 (69%) non-exposed children had less than 80 copies/ml [aOR 1.75 (0.93-3.29), P = 0.08]. There was no difference between children with and without previous sdNVP exposure in intermediate/high-level resistance to NRTIs (P > 0.3) or NNRTIs (P > 0.1) (n = 88) at week 144. CONCLUSION: Given the limited global availability of lopinavir/ritonavir, its significant formulation challenges in young children, and the significant paediatric treatment gap, tablet fixed-dose-combination NVP-based ART remains a good alternative to syrup lopinavir-based ART for children, particularly those over 1 year and even if exposed to sdNVP.