Birgit Grund

Major clinical outcomes in antiretroviral therapy (ART)-naive participants and in those not receiving ART at baseline in the SMART study.

BACKGROUND The SMART study randomized 5,472 human immunodeficiency virus (HIV)-infected patients with CD4+ cell counts >350 cells/microL to intermittent antiretroviral therapy (ART; the drug conservation [DC] group) versus continuous ART (the viral suppression [VS] group). In the DC group, participants started ART when the CD4+ cell count was <250 cells/microL. Clinical outcomes in participants not receiving ART at entry inform the early use of ART. METHODS Patients who were either ART naive (n=249) or who had not been receiving ART for >or= 6 months (n=228) were analyzed. The following clinical outcomes were assessed: (i) opportunistic disease (OD) or death from any cause (OD/death); (ii) OD (fatal or nonfatal); (iii) serious non-AIDS events (cardiovascular, renal, and hepatic disease plus non-AIDS-defining cancers) and non-OD deaths; and (iv) the composite of outcomes (ii) and (iii). RESULTS A total of 477 participants (228 in the DC group and 249 in the VS group) were followed (mean, 18 months). For outcome (iv), 21 and 6 events occurred in the DC (7 in ART-naive participants and 14 in those who had not received ART for >or= 6 months) and VS (2 in ART-naive participants and 4 in those who had not received ART for 6 months) groups, respectively. Hazard ratios for DC vs. VS by outcome category were as follows: outcome (i), 3.47 (95% confidence interval [CI], 1.26-9.56; p=.02); outcome (ii), 3.26 (95% CI, 1.04-10.25; p=.04); outcome (iii), 7.02 (95% CI, 1.57-31.38; p=.01); and outcome (iv), 4.19 (95% CI, 1.69-10.39; p=.002 ). CONCLUSIONS Initiation of ART at CD4+ cell counts >350 cells/microL compared with <250 cells/microL may reduce both OD and serious non-AIDS events. These findings require validation in a large, randomized clinical trial.Background. The SMART study randomized 5472 human immunodeficiency virus (HIV)-infected patients with CD4 + cell counts >350 cells/μL to intermittent antiretroviral therapy (ART; the drug conservation [DC] group) versus continuous ART (the viral supression [VS] group). In the DC group, participants started ART when the CD4 + cell count was 350 cells/μL compared with <250 cells/μL may reduce both OD and serious non-AIDS events. These findings require validation in a large, randomized clinical trial.

Continuous antiretroviral therapy decreases bone mineral density.

Objectives:To assess the effects of antiretroviral therapy (ART) on bone mineral density (BMD) Design:Randomized comparison of continuous ART (viral suppression group; VS) with intermittent ART (drug conservation group; DC) Setting:Outpatient clinics in the United States, Australia, and Spain. Participants:Participants in the Strategies for Management of Antiretroviral Therapy (SMART) Body Composition substudy. Main outcome measures:Annual hip and spine BMD by dual-energy radiographic absorptiometry (DXA) and spine BMD by quantitative computed tomography (qCT). Methods:Comparisons were by intention-to-treat analysis, using longitudinal models for change in BMD. Risk factors for BMD loss were evaluated. Results:The 214 participants (median 44 years, 19% female participants, 73% on ART; median T-scores −0.5 total hip, −0.7 spine DXA, −0.9 spine qCT; 98 randomized to VS and 116 to DC) were followed for a mean 2.4 years. With continuous ART, BMD declined per year by 0.8% (hip), 0.4% (spine DXA), and 2.4% (spine qCT). BMD declined significantly less with intermittent ART. Estimated DC minus VS group differences in mean BMD change through follow-up were 1.4% [hip; 95% confidence interval (CI) 0.6–2.3; P = 0.002], 1.3% (spine DXA; 95% CI 0.1–2.4, P = 0.03), and 3.0% (spine qCT; 95% CI 0.8–5.2, P = 0.007). No consistent drug-specific association with BMD decline was found. In the parent study, 10 of 2753 participants in the VS group and two of 2720 in the DC group reported serious fractures (hazard ratio 4.9; 95% CI 1.1–22.5; P = 0.04). Conclusion:Continuous ART is associated with decline in BMD and possibly more fractures relative to intermittent, CD4 cell count-guided ART.

Inferior clinical outcome of the CD4+ cell count-guided antiretroviral treatment interruption strategy in the SMART study: role of CD4+ Cell counts and HIV RNA levels during follow-up.

BACKGROUND AND METHODS The SMART study compared 2 strategies for using antiretroviral therapy-drug conservation (DC) and viral suppression (VS)-in 5,472 human immunodeficiency virus (HIV)-infected patients with CD4+ cell counts >350 cells/microL. Rates and predictors of opportunistic disease or death (OD/death) and the relative risk (RR) in DC versus VS groups according to the latest CD4+ cell count and HIV RNA level are reported. RESULTS During a mean of 16 months of follow-up, DC patients spent more time with a latest CD4+ cell count <350 cells/microL (for DC vs. VS, 31% vs. 8%) and with a latest HIV RNA level >400 copies/mL (71% vs. 28%) and had a higher rate of OD/death (3.4 vs. 1.3/100 person-years) than VS patients. For periods of follow- up with a CD4+ cell count <350 cells/microL, rates of OD/death were increased but similar in the 2 groups (5.7 vs. 4.6/100 person-years), whereas the rates were higher in DC versus VS patients (2.3 vs. 1.0/100 person-years; RR, 2.3 [95% confidence interval, 1.5-3.4]) for periods with the latest CD4+ cell count >or= 350 cells/microL-an increase explained by the higher HIV RNA levels in the DC group. CONCLUSIONS The higher risk of OD/death in DC patients was associated with (1) spending more follow-up time with relative immunodeficiency and (2) living longer with uncontrolled HIV replication even at higher CD4+ cell counts. Ongoing HIV replication at a given CD4+ cell count places patients at an excess risk of OD/death.

Risk for opportunistic disease and death after reinitiating continuous antiretroviral therapy in patients with HIV previously receiving episodic therapy - a randomized trial

BACKGROUND Episodic use of antiretroviral therapy guided by CD4+ cell counts is inferior to continuous antiretroviral therapy. OBJECTIVE To determine whether reinitiating continuous antiretroviral therapy in patients who received episodic treatment reduces excess risk for opportunistic disease or death. DESIGN Randomized, controlled trial. SETTING Sites in 33 countries. PATIENTS 5472 HIV-infected individuals with CD4(+) cell counts greater than 0.350 x 10(9) cells/L enrolled from January 2002 to January 2006. INTERVENTION Episodic or continuous antiretroviral therapy initially, followed by continuous therapy in participants previously assigned to episodic treatment. MEASUREMENTS Opportunistic disease or death was the primary outcome. RESULTS Eighteen months after the recommendation to reinitiate continuous therapy, mean CD4+ cell counts were 0.152 x 10(9) cells/L (95% CI, 0.136 to 0.167 x 10(9) cells/L) less in participants previously assigned to episodic treatment (P < 0.001). The proportion of follow-up time spent with CD4+ cell counts of 0.500 x 10(9) cells/L or more and HIV RNA levels of 400 copies/mL or less was 29% for participants initially assigned to episodic therapy and 66% for those assigned to continuous therapy. Participants who reinitiated continuous therapy experienced rapid suppression of HIV RNA levels (89.7% with HIV RNA levels < or =400 copies/mL after 6 months), but CD4+ cell counts after 6 months remained 0.140 x 10(9) cells/L below baseline. The hazard ratio (episodic versus continuous treatment) for opportunistic disease or death decreased after the recommendation to reinitiate continuous therapy (from 2.5 [CI, 1.8 to 3.5] to 1.4 [CI, 1.0 to 2.0]; P = 0.033 for difference). The residual excess risk was attributable to failure to reinitiate therapy by some participants and slow recovery of CD4+ cell counts for those who reinitiated therapy. LIMITATION Follow-up was too short to assess the full effect of switching from episodic to continuous antiretroviral therapy. CONCLUSION Reinitiating continuous antiretroviral therapy in patients previously assigned to episodic treatment reduced excess risk for opportunistic disease or death, but excess risk remained. Episodic antiretroviral therapy, as used in the SMART study, should be avoided.

Cardiovascular risk factors associated with lower baseline cognitive performance in HIV-positive persons

Objective: To determine factors associated with baseline neurocognitive performance in HIV-infected participants enrolled in the Strategies for Management of Antiretroviral Therapy (SMART) neurology substudy. Methods: Participants from Australia, North America, Brazil, and Thailand were administered a 5-test neurocognitive battery. Z scores and the neurocognitive performance outcome measure, the quantitative neurocognitive performance z score (QNPZ-5), were calculated using US norms. Neurocognitive impairment was defined as z scores <−2 in two or more cognitive domains. Associations of test scores, the QNPZ-5, and impairment with baseline factors including demographics and risk factors for HIV-associated dementia (HAD) and cardiovascular disease (CVD) were determined in multiple regression. Results: The 292 participants had a median CD4 cell count of 536 cells/mm3, 88% had an HIV viral load ≤400 copies/mL, and 92% were taking antiretrovirals. Demographics, HIV, and clinical factors differed between locations. The mean QNPZ-5 score was −0.72; 14% of participants had neurocognitive impairment. For most tests, scores and z scores differed significantly between locations, with and without adjustment for age, sex, education, and race. Prior CVD was associated with neurocognitive impairment. Prior CVD, hypercholesterolemia, and hypertension were associated with poorer neurocognitive performance but conventional HAD risk factors and the CNS penetration effectiveness rank of antiretroviral regimens were not. Conclusions: In this HIV-positive population with high CD4 cell counts, neurocognitive impairment was associated with prior CVD. Lower neurocognitive performance was associated with prior CVD, hypertension, and hypercholesterolemia, but not conventional HAD risk factors. The contribution of CVD and cardiovascular risk factors to the neurocognition of HIV-positive populations warrants further investigation.

Considerations in the rationale, design and methods of the Strategic Timing of AntiRetroviral Treatment (START) study:

Background Untreated human immunodeficiency virus (HIV) infection is characterized by progressive depletion of CD4+ T lymphocyte (CD4) count leading to the development of opportunistic diseases (acquired immunodeficiency syndrome (AIDS)), and more recent data suggest that HIV is also associated with an increased risk of serious non-AIDS (SNA) diseases including cardiovascular, renal, and liver diseases and non-AIDS-defining cancers. Although combination antiretroviral treatment (ART) has resulted in a substantial decrease in morbidity and mortality in persons with HIV infection, viral eradication is not feasible with currently available drugs. The optimal time to start ART for asymptomatic HIV infection is controversial and remains one of the key unanswered questions in the clinical management of HIV-infected individuals. Purpose In this article, we outline the rationale and methods of the Strategic Timing of AntiRetroviral Treatment (START) study, an ongoing multicenter international trial designed to assess the risks and benefits of initiating ART earlier than is currently practiced. We also describe some of the challenges encountered in the design and implementation of the study and how these challenges were addressed. Methods A total of 4000 study participants who are HIV type 1 (HIV-1) infected, ART naïve with CD4 count > 500 cells/µL are to be randomly allocated in a 1:1 ratio to start ART immediately (early ART) or defer treatment until CD4 count is <350 cells/µL (deferred ART) and followed for a minimum of 3 years. The primary outcome is time to AIDS, SNA, or death. The study had a pilot phase to establish feasibility of accrual, which was set as the enrollment of at least 900 participants in the first year. Results Challenges encountered in the design and implementation of the study included the limited amount of data on the risk of a major component of the primary endpoint (SNA) in the study population, changes in treatment guidelines when the pilot phase was well underway, and the complexities of conducting the trial in a geographically wide population with diverse regulatory requirements. With the successful completion of the pilot phase, more than 1000 participants from 100 sites in 23 countries have been enrolled. The study will expand to include 237 sites in 36 countries to reach the target accrual of 4000 participants. Conclusions START is addressing one of the most important questions in the clinical management of ART. The randomization provided a platform for the conduct of several substudies aimed at increasing our understanding of HIV disease and the effects of antiretroviral therapy beyond the primary question of the trial. The lessons learned from its design and implementation will hopefully be of use to future publicly funded international trials.

Analysis of biomarker data: logs, odds ratios, and receiver operating characteristic curves.

Purpose of reviewWe discuss two data analysis issues for studies that use binary clinical outcomes (whether or not an event occurred): the choice of an appropriate scale and transformation when biomarkers are evaluated as explanatory factors in logistic regression and assessing the ability of biomarkers to improve prediction accuracy for event risk. Recent findingsBiomarkers with skewed distributions should be transformed before they are included as continuous covariates in logistic regression models. The utility of new biomarkers may be assessed by measuring the improvement in predicting event risk after adding the biomarkers to an existing model. The area under the receiver operating characteristic (ROC) curve (C-statistic) is often cited; it was developed for a different purpose, however, and may not address the clinically relevant questions. Measures of risk reclassification and risk prediction accuracy may be more appropriate. SummaryThe appropriate analysis of biomarkers depends on the research question. Odds ratios obtained from logistic regression describe associations of biomarkers with clinical events; failure to accurately transform the markers, however, may result in misleading estimates. Although the C-statistic is often used to assess the ability of new biomarkers to improve the prediction of event risk, other measures may be more suitable.

Phase 2 Placebo-Controlled Trial of Two Vaccines to Prevent Ebola in Liberia

BACKGROUND The safety and efficacy of vaccines to prevent Ebola virus disease (EVD) were unknown when the incidence of EVD was peaking in Liberia. METHODS We initiated a randomized, placebo‐controlled, phase 3 trial of the chimpanzee adenovirus 3 vaccine (ChAd3‐EBO‐Z) and the recombinant vesicular stomatitis virus vaccine (rVSV&Dgr;G‐ZEBOV‐GP) in Liberia. A phase 2 subtrial was embedded to evaluate safety and immunogenicity. Because the incidence of EVD declined in Liberia, the phase 2 component was expanded and the phase 3 component was eliminated. RESULTS A total of 1500 adults underwent randomization and were followed for 12 months. The median age of the participants was 30 years; 36.6% of the participants were women. During the week after the administration of vaccine or placebo, adverse events occurred significantly more often with the active vaccines than with placebo; these events included injection‐site reactions (in 28.5% of the patients in the ChAd3‐EBO‐Z group and 30.9% of those in the rVSV&Dgr;G‐ZEBOV‐GP group, as compared with 6.8% of those in the placebo group), headache (in 25.1% and 31.9%, vs. 16.9%), muscle pain (in 22.3% and 26.9%, vs. 13.3%), feverishness (in 23.9% and 30.5%, vs. 9.0%), and fatigue (in 14.0% and 15.4%, vs. 8.8%) (P<0.001 for all comparisons); these differences were not seen at 1 month. Serious adverse events within 12 months after injection were seen in 40 participants (8.0%) in the ChAd3‐EBO‐Z group, in 47 (9.4%) in the rVSV&Dgr;G‐ZEBOV‐GP group, and in 59 (11.8%) in the placebo group. By 1 month, an antibody response developed in 70.8% of the participants in the ChAd3‐EBO‐Z group and in 83.7% of those in the rVSV&Dgr;G‐ZEBOV‐GP group, as compared with 2.8% of those in the placebo group (P<0.001 for both comparisons). At 12 months, antibody responses in participants in the ChAd3‐EBO‐Z group (63.5%) and in those in the rVSV&Dgr;G‐ZEBOV‐GP group (79.5%) remained significantly greater than in those in the placebo group (6.8%, P<0.001 for both comparisons). CONCLUSIONS A randomized, placebo‐controlled phase 2 trial of two vaccines that was rapidly initiated and completed in Liberia showed the capability of conducting rigorous research during an outbreak. By 1 month after vaccination, the vaccines had elicited immune responses that were largely maintained through 12 months. (Funded by the National Institutes of Allergy and Infectious Diseases and the Liberian Ministry of Health; PREVAIL I ClinicalTrials.gov number, NCT02344407.)

Relevance of Interleukin-6 and D-Dimer for Serious Non-AIDS Morbidity and Death among HIV-Positive Adults on Suppressive Antiretroviral Therapy.

Background Despite effective antiretroviral treatment (ART), HIV-positive individuals are at increased risk of serious non-AIDS conditions (cardiovascular, liver and renal disease, and cancers), perhaps due in part to ongoing inflammation and/or coagulation. To estimate the potential risk reduction in serious non-AIDS conditions or death from any cause that might be achieved with treatments that reduce inflammation and/or coagulation, we examined associations of interleukin-6 (IL-6), D-dimer, and high-sensitivity C-reactive protein (hsCRP) levels with serious non-AIDS conditions or death in 3 large cohorts. Methods In HIV-positive adults on suppressive ART, associations of IL-6, D-dimer, and hsCRP levels at study entry with serious non-AIDS conditions or death were studied using Cox regression. Hazard ratios (HR) adjusted for age, gender, study, and regression dilution bias (due to within-person biomarker variability) were used to predict risk reductions in serious non-AIDS conditions or death associated with lower “usual” levels of IL-6 and D-dimer. Results Over 4.9 years of mean follow-up, 260 of the 3766 participants experienced serious non-AIDS conditions or death. IL-6, D-dimer and hsCRP were each individually associated with risk of serious non-AIDS conditions or death, HR = 1.45 (95% CI: 1.30 to 1.63), 1.28 (95% CI: 1.14 to 1.44), and 1.17 (95% CI: 1.09 to 1.26) per 2x higher biomarker levels, respectively. In joint models, IL-6 and D-dimer were independently associated with serious non-AIDS conditions or death, with consistent results across the 3 cohorts and across serious non-AIDS event types. The association of IL-6 and D-dimer with serious non-AIDS conditions or death was graded and persisted throughout follow-up. For 25% lower “usual” IL-6 and D-dimer levels, the joint biomarker model estimates a 37% reduction (95% CI: 28 to 46%) in the risk of serious non-AIDS conditions or death if the relationship is causal. Conclusions Both IL-6 and D-dimer are independently associated with serious non-AIDS conditions or death among HIV-positive adults with suppressed virus. This suggests that treatments that reduce IL-6 and D-dimer levels might substantially decrease morbidity and mortality in patients on suppressive ART. Clinical trials are needed to test this hypothesis.

Why START? Reflections that led to the conduct of this large long-term strategic HIV trial

This monograph describes a cohort of 4685 HIV-positive persons, most of whom were recently infected, who volunteered to dedicate several years to being participants in a research study that addresses the question of when antiretroviral therapy (ART) should be initiated. Should it be started early after HIV infection occurs, or should it be deferred until the infection has started to impair immune function but before the risk of AIDS increases? There has been consensus based on robust data for many years that ART should be initiated following the development of AIDS. Also, within the past 6 to 7 years, data from randomized trials [1–3] and observational studies [4–7] emerged that supported the initiation of ART when the CD4 cell count declined to < 350 cells/μL among asymptomatic individuals. It has been hotly debated whether the clinical benefits of initiating ART at a CD4 cell count > 500 cells/ μL, compared with deferring ART until the CD4 cell count decreases to 350 cells/μL, as is being tested in the Strategic Timing of AntiRetroviral Treatment (START) study, outweigh the risks [8–10]. The debate is lively because the data available are not optimal. The fact that 4685 persons from 215 clinics in 35 countries volunteered to be randomized in START reflects the considerable uncertainty that many individuals with HIV infection and investigators around the world have about the answer to the question being addressed by START.