Changes Over Time in Risk of Initial Virological Failure of Combination Antiretroviral Therapy

Long-Term Clinical Outcomes After Autologous Hematopoietic Stem Cell Transplantation in 49 Individuals Living With HIV (PLWH) and Affected by High-Risk or Relapsed Lymphoma: A European Experience of Continued Relevance for PLWH

Previous reports have indicated that during the era of combination antiretroviral therapy, the major causes of morbidity and mortality in people living with HIV (PLWH) were not solely linked to HIV-related opportunistic infections but also to cancers that were difficult to manage due to HIV-related immunodeficiency. We investigated whether PLWH who underwent autologous hematopoietic stem cell transplantation (ASCT) for lymphomas experienced significant morbidity over the past thirty years following HIV infection. We conducted a retrospective follow-up study of 49 PLWH over a 10-year period following ASCT. We collected survival data, examined the occurrence of long-term events, assessed CD4 + T-cell immune recovery, and analysed the correlation between immune recovery and the events experienced by these patients. The data confirmed the significant long-term effectiveness of ASCT, with an overall survival rate of 78% at 10 years post-ASCT. Opportunistic infections, which occurred soon after ASCT and were associated with lower CD4 + T-cell counts, were successfully managed. However, lymphoma relapse, secondary malignancies, cardiovascular disease, and bone disease, which developed years after ASCT, were major causes of morbidity and mortality in this population. Our findings highlight the need for the development and validation of specific tests to predict risk and guide effective interventions for metabolic diseases, secondary malignancies, and lymphoma relapses in PLWH treated with ASCT for lymphoma.

Identifying causes of persistent HIV viremia in adult patients at an academic medical center

Objectives:

Despite many advances in medicine, not all individuals with HIV are able to achieve complete virologic suppression. This retrospective study identifies variables associated with persistent HIV viremia in an academic clinic.

Methods:

We studied 66 HIV-infected patients with a viral load of >200 copies/mL over 1 year, with controls matched 1:1 via a propensity score utilizing age at diagnosis, era of diagnosis, gender, and initial CD4 count. We collected data on multiple variables including medications, adherence, comorbidities, hospitalizations, and insurance status. Conditional logistic regression was used for unadjusted and adjusted analyses.

Results:

A total of 66 viremic cases/matched controls were included. Fewer viremic patients were on antiretroviral therapy for all 12 months (45% vs 77%; odds ratio: 0.33, p = .018) and fewer were of white race (52% vs 70%; odds ratio: 0.49, p = .053). Hospitalization (11% vs 3%; odds ratio: 10, p = .028), underinsurance (20% vs 1%; odds ratio: 5.87, p = .022), and conflicting personal beliefs about their disease (17% vs 3%; odds ratio: 5.5, p = .027) were more common in viremic patients. Psychiatric illness increased the odds of viremia in patients who had four or more visits (odds ratio: 1.63/6.64 with four/five clinic visits, respectively).

Conclusion:

Psychiatric illness is an important contributor to the presence of persistent viremia in HIV-infected patients and deserves further study.

Where is the greatest impact of uncontrolled HIV infection on AIDS and non-AIDS events in HIV?

OBJECTIVE

The extent to which controlled and uncontrolled HIV interact with ageing, European region of care and calendar year of follow-up is largely unknown.

METHOD

EuroSIDA participants were followed after 1 January 2001 and grouped according to current HIV progression risk; high risk (CD4 cell count ≤350/μl, viral load ≥10 000 copies/ml), low risk (CD4 cell count ≥500 cells/μl, viral load <50 copies/ml) and intermediate (other combinations). Poisson regression investigated interactions between HIV progression risk, age, European region of care and year of follow-up and incidence of AIDS or non-AIDS events.

RESULTS

A total of 16 839 persons were included with 136 688 person-years of follow-up. In persons aged 30 years or less, those at high risk had a six-fold increased incidence of non-AIDS compared with those at low risk, compared with a two-to-three-fold increase in older persons (P = 0.0004, interaction). In Eastern Europe, those at highest risk of non-AIDS had a 12-fold increased incidence compared with a two-to-four-fold difference in all other regions (P = 0.0029, interaction). Those at high risk of non-AIDS during 2001-2004 had a two-fold increased incidence compared with those at low risk, increasing to a five-fold increase between 2013 and 2016 (P < 0.0001, interaction). Differences among high, intermediate and low risk of AIDS were similar across age groups, year of follow-up and Europe (P = 0.57, 0.060 and 0.090, respectively, interaction).

CONCLUSION

Factors other than optimal control of HIV become increasingly important with ageing for predicting non-AIDS, whereas differences across Europe reflect differences in patient management as well as underlying socioeconomic circumstances. The differences between those at high, intermediate and low risk of non-AIDS between 2013 and 2016 likely reflects better quality of care.

Durability of viral suppression with first-line antiretroviral therapy in patients with HIV in the UK: an observational cohort study

BACKGROUND

The length of time that people with HIV on antiretroviral therapy (ART) with viral load suppression will be able to continue before developing viral rebound is unknown. We aimed to investigate the rate of first viral rebound in people that have achieved initial suppression with ART, to determine factors associated with viral rebound, and to use these estimates to predict long-term durability of viral suppression.

METHODS

The UK Collaborative HIV Cohort (UK CHIC) Study is an ongoing multicentre cohort study that brings together in a standardised format data on people with HIV attending clinics around the UK. We included participants who started ART with three or more drugs and who had achieved viral suppression (≤50 copies per mL) by 9 months after the start of ART (baseline). Viral rebound was defined as the first single viral load of more than 200 copies per mL or treatment interruption (for ≥1 month). We investigated factors associated with viral rebound with Poisson regression. These results were used to calculate the rate of viral rebound according to several key factors, including age, calendar year at start of ART, and time since baseline.

RESULTS

Of the 16 101 people included, 4519 had a first viral rebound over 58 038 person-years (7·8 per 100 person-years, 95% CI 7·6-8·0). Of the 4519 viral rebounds, 3105 (69%) were defined by measurement of a single viral load of more than 200 copies per mL, and 1414 (31%) by a documented treatment interruption. The rate of first viral rebound declined substantially over time until 7 years from baseline. The other factors associated with viral rebound were current age at follow-up and calendar year at ART initiation (p<0·0001) and HIV risk group (p<0·0001); higher pre-ART CD4 count (p=0·0008) and pre-ART viral load (p=0·0003) were associated with viral rebound in the multivariate analysis only. For 1322 (29%) of the 3105 people with observed viral rebound, the next viral load value after rebound was 50 copies per mL or less with no regimen change. For HIV-positive men who have sex with men, our estimates suggest that the probability of first viral rebound reaches a plateau of 1·4% per year after 45 years of age, and 1·0% when accounting for the fact that 29% of viral rebounds are temporary elevations.

INTERPRETATION

A substantial proportion of people on ART will not have viral rebound over their lifetime, which has implications for people with HIV and the planning of future drug development.

FUNDING

UK Medical Research Council.

Using drug exposure for predicting drug resistance - A data-driven genotypic interpretation tool

Antiretroviral treatment history and past HIV-1 genotypes have been shown to be useful predictors for the success of antiretroviral therapy. However, this information may be unavailable or inaccurate, particularly for patients with multiple treatment lines often attending different clinics. We trained statistical models for predicting drug exposure from current HIV-1 genotype. These models were trained on 63,742 HIV-1 nucleotide sequences derived from patients with known therapeutic history, and on 6,836 genotype-phenotype pairs (GPPs). The mean performance regarding prediction of drug exposure on two test sets was 0.78 and 0.76 (ROC-AUC), respectively. The mean correlation to phenotypic resistance in GPPs was 0.51 (PhenoSense) and 0.46 (Antivirogram). Performance on prediction of therapy-success on two test sets based on genetic susceptibility scores was 0.71 and 0.63 (ROC-AUC), respectively. Compared to geno2pheno_[resistance], our novel models display a similar or superior performance. Our models are freely available on the internet via www.geno2pheno.org. They can be used for inferring which drug compounds have previously been used by an HIV-1-infected patient, for predicting drug resistance, and for selecting an optimal antiretroviral therapy. Our data-driven models can be periodically retrained without expert intervention as clinical HIV-1 databases are updated and therefore reduce our dependency on hard-to-obtain GPPs.

Immunosenescence and hurdles in the clinical management of older HIV-patients

People living with HIV (PLWH) who are treated with effective highly active antiretroviral therapy (HAART) have a similar life expectancy to the general population. Moreover, an increasing proportion of new HIV diagnoses are made in people older than 50 y. The number of older HIV-infected patients is thus constantly growing and it is expected that by 2030 around 70% of PLWH will be more than 50 y old. On the other hand, HIV infection itself is responsible for accelerated immunosenescence, a progressive decline of immune system function in both the adaptive and the innate arm, which impairs the ability of an individual to respond to infections and to give rise to long-term immunity; furthermore, older patients tend to have a worse immunological response to HAART. In this review we focus on the pathogenesis of HIV-induced immunosenescence and on the clinical management of older HIV-infected patients.

Incidence of virological failure and major regimen change of initial combination antiretroviral therapy in the Latin America and the Caribbean: an observational cohort study

BACKGROUND

Access to combination antiretroviral therapy (ART) is expanding in Latin America (Mexico, Central America, and South America) and the Caribbean. We assessed the incidence of and factors associated with regimen failure and regimen change of initial ART in this region.

METHODS

This observational cohort study included antiretroviral-naive adults starting ART from 2000 to 2014 at sites in seven countries throughout Latin America and the Caribbean. Primary outcomes were time from ART initiation until virological failure, major regimen modification, and a composite endpoint of the first of virological failure or major regimen modification. Cumulative incidence of the primary outcomes was estimated with death considered a competing event.

FINDINGS

14,027 patients starting ART were followed up for a median of 3.9 years (2.0-6.5): 8374 (60%) men, median age 37 years (IQR 30-44), median CD4 count 156 cells per μL (61-253), median plasma HIV RNA 5.0 log10 copies per mL (4.4-5.4), and 3567 (28%) had clinical AIDS. 1719 (12%) patients had virological failure and 1955 (14%) had a major regimen change. Excluding the site in Haiti, which did not regularly measure HIV RNA, cumulative incidence of virological failure was 7.8% (95% CI 7.2-8.5) 1 year after ART initiation, 19.2% (18.2-20.2) at 3 years, and 25.8% (24.6-27.0) at 5 years; cumulative incidence of major regimen change was 5.9% (5.3-6.4) at 1 year, 12.7% (11.9-13.5) at 3 years, and 18.2% (17.2-19.2) at 5 years. Incidence of major regimen change at the site in Haiti was 10.7% (95% CI 9.7-11.6) at 5 years. Virological failure was associated with younger age (adjusted hazard ratio [HR] 2.03, 95% CI 1.68-2.44, for 20 years vs 40 years), infection through injection drug use (vs infection through heterosexual sex; 1.60, 1.02-2.52), and initiation in earlier calendar years (1.28, 1.13-1.46, for 2002 vs 2006), but was not significantly associated with boosted protease inhibitor-based regimens (vs non-nucleoside reverse transcriptase inhibitor; 1.17, 1.00-1.36).

INTERPRETATION

Incidence of virological failure in Latin America and the Caribbean was generally lower than that reported in North America or Europe. Our results suggest the need to design strategies to reduce failure and major regimen change in young patients and those with a history of injection drug use.

FUNDING

US National Institutes of Health.

Treatment Modifications and Treatment-Limiting Toxicities or Side Effects: Risk Factors and Temporal Trends

Combined antiretroviral treatment (cART) modifications are often required due to treatment failure or side effects. We investigate cART regimens' durability, frequency of treatment-limiting adverse events, and potential risk factors and temporal trends. Data were derived from the Athens Multicenter AIDS Cohort Study (AMACS). Statistical analyses were based on survival techniques, allowing for multiple contributions per individual. Overall, 2,756 individuals, aged >15 years, initiated cART. cART regimens were grouped by their initiation date into four calendar periods (1995-1998, 1999-2002, 2003-2006, and 2007+). Median [95% confidence interval (CI)] time to first treatment modification was 2.11 (1.95-2.33) years; cumulative probabilities at 1 year were 31.6%, 29.0%, 33.1%, and 29.6% for the four periods, respectively. cART modifications were less frequent in more recent years (adjusted HR=0.96 per year; p<0.001). Longer treatment duration was associated with lower HIV-RNA, higher CD4 counts, and being previously ART naive. cART modifications due to treatment failure became less frequent in recent years (adjusted HR=0.91 per year; p<0.001). Estimated (95% CI) 1 year cumulative probabilities of treatment-limiting side effects were 16.4% (12.0-21.3%), 19.3% (15.6-23.3%), 24.9% (20.3-29.7%), and 21.1% (13.4-29.9%) for the four periods, respectively, with no significant temporal trends. Risk of side effects was lower in nonnucleoside reverse transcriptase inhibitor (NNRTI)-based regimens or triple nucleoside reverse transcriptase inhibitor (NRTI)-based cART regimens. Treatment modifications have become less frequent in more recent years. This could be partly attributed to the lower risk for side effects of NNRTI-based cART regimens and mainly to the improved efficacy of newer drugs. However, the rate of drugs substitutions due to adverse events remains substantially high.

Projected Lifetime Healthcare Costs Associated with HIV Infection

Objective

Estimates of healthcare costs associated with HIV infection would provide valuable insight for evaluating the cost-effectiveness of possible prevention interventions. We evaluate the additional lifetime healthcare cost incurred due to living with HIV.

Methods

We used a stochastic computer simulation model to project the distribution of lifetime outcomes and costs of men-who-have-sex-with-men (MSM) infected with HIV in 2013 aged 30, over 10,000 simulations. We assumed a resource-rich setting with no loss to follow-up, and that standards and costs of healthcare management remain as now.

Results

Based on a median (interquartile range) life expectancy of 71.5 (45.0–81.5) years for MSM in such a setting, the estimated mean lifetime cost of treating one person was £360,800 ($567,000 or €480,000). With 3.5% discounting, it was £185,200 ($291,000 or €246,000). The largest proportion (68%) of these costs was attributed to antiretroviral drugs. If patented drugs are replaced by generic versions (at 20% cost of patented prices), estimated mean lifetime costs reduced to £179,000 ($281,000 or €238,000) and £101,200 ($158,900 or €134,600) discounted.

Conclusions

If 3,000 MSM had been infected in 2013, then future lifetime costs relating to HIV care is likely to be in excess of £1 billion. It is imperative for investment into prevention programmes to be continued or scaled-up in settings with good access to HIV care services. Costs would be reduced considerably with use of generic antiretroviral drugs.

Modelling the HIV epidemic among MSM in the United Kingdom: quantifying the contributions to HIV transmission to better inform prevention initiatives

OBJECTIVES

HIV is a major public health problem among MSM in the United Kingdom with around 2400 new infections annually. We quantified the contribution of biological and behavioural factors.

DESIGN

Modelling study.

METHODS

A partnership-based model of HIV transmission among UK MSM aged 15-64 years was developed and calibrated to time series HIV prevalence. The calibration was validated using multiple surveillance datasets. Population-attributable fractions were used to estimate the contribution of behavioural and biological factors to HIV transmission over the period 2001-2002, 2014-2015, and 2019-2020.

RESULTS

The contribution of most biological and behavioural factors was relatively constant over time, with the key group sustaining HIV transmission being higher-sexual activity MSM aged below 35 years living with undiagnosed HIV. The effect of primary HIV infection was relatively small with 2014-2015 population-attributable fraction of 10% (3-28%) in comparison with other subsequent asymptomatic stages. Diagnosed men who were not on antiretroviral therapy (ART) currently contributed 26% (14-39%) of net infections, whereas ART-treated MSM accounted for 17% (10-24%). A considerable number of new infections are also likely to occur within long-term relationships.

CONCLUSION

The majority of the new HIV infections among MSM in the United Kingdom during 2001-2020 is expected to be accounted for by a small group of younger and highly sexually active individuals, living with undiagnosed HIV in the asymptomatic stage. Bringing this group into HIV/AIDS care by improving testing uptake is a vital step for preventing onward transmission and will determine the success of using ART as prevention.

Comparison of Single and Boosted Protease Inhibitor Versus Nonnucleoside Reverse Transcriptase Inhibitor–Containing cART Regimens in Antiretroviral-Naïve Patients Starting cART After January 1, 2000

BACKGROUND

Few published studies have considered both the short- and long-term virologic or immunologic response to combination antiretroviral therapy (cART) and the impact of different cART strategies.

PURPOSE

To compare time to initial virologic (<500 copies/mL) or immunologic (>200/mm3 cell increase) response in antiretroviral-naïve patients starting either a single protease inhibitor (PI; n = 183), a ritonavir-boosted PI regimen (n = 197), or a nonnucleoside reverse transcriptase inhibitor (NNRTI)-based cART regimen (n = 447) after January 1, 2000, and the odds of lack of virologic or immunologic response at 3 years after starting cART.

METHOD

Cox proportional hazards models and logistic regression.

RESULTS

After adjustment, compared to patients taking an NNRTI-regimen, patients taking a single-PI regimen were significantly less likely to achieve a viral load (VL) <500 copies/mL (relative hazard [RH] 0.74, 95% CI 0.54-0.84, p = .0005); there was no difference between the boosted-PI regimen and the NNRTI regimen (p = .72). There were no differences between regimens in the risk of >200/mm3 CD4 cell increase after starting cART (p > .3). At 3 years after starting cART, patients taking a single-PI-based regimen were more likely to not have virologic suppression (<500 copies/mL; odds ratio [OR] 1.60, 95% CI 1.06-2.40, p = .024), while there were no differences in the odds of having an immunologic response (>200/mm3 increase; p > .15). This model was adjusted for CD4 and VL at starting cART, age, prior AIDS diagnosis, year of starting cART, and region of Europe.

CONCLUSION

Compared to patients starting an NNRTI-based regimen, patients starting a single-PI regimen were less likely to be virologically suppressed at 3 years after starting cART. These results should be interpreted with caution, because of the potential biases associated with observational studies. Ultimately, clinical outcomes, such as new AIDS diagnoses or deaths, will be the measure of efficacy of cART regimens, which requires the follow-up of a very large number of patients over many years.

Economic impact of HIV/AIDS: a systematic review in five European countries

The HIV/AIDS disease represent a priority for all health authorities in all countries and it also represents serious added socioeconomic problems for societies over the world. The aim of this paper is to analize the economic impact associated to the HIV/AIDS in an European context. We conducted a systematic literature review for five different countries (France, Germany, Italy, Spain and United Kingdom) and searched five databases. Three types of analyses were undertaken: descriptive statistics; quantitative analysis to calculate mean costs; and comparison across countries. 26 papers were included in this study containing seventy-six cost estimates. Most of the studies analyzed the health care cost of treatment of HIV/AIDS. Only 50% of the cost estimates provided mean lymphocyte count describing the patients' disease stage. Approximately thirty percent of cost estimates did not indicate the developmental stage of the illness in the patients included. There is a high degree of variability in the estimated annual cost per patient of the treatments across countries. There is also a great disparity in total healh care costs for patients with lymphocyte counts between 200CD4+/mm3 and 500 CD4/mm3, although the reason of variation is unclear. In spite of the potential economic impact in terms of productivity losses and cost of formal and informal care, few studies have set out to estimate the non-medical costs of HIV/AIDS in the countries selected. Another important result is that, despite the low HIV/AIDS prevalence, its economic burden is very relevant in terms of the total health care costs in this five countries. This study also shows that there are relatively few studies of HIV costs in European countries compared to other diseases. Finally, we conclude that the methodology used in many of the studies carried out leaves ample room for improvement and that there is a need for these studies to reflect the economic impact of HIV/AIDS beyond health care including other components of social burden.

Effect of mobile telephone reminders on treatment outcome in HIV: evidence from a randomised controlled trial in India

OBJECTIVE

To assess whether customised mobile phone reminders would improve adherence to therapy and thus decrease virological failure among HIV infected patients starting antiretroviral treatment (ART).

DESIGN

Randomised controlled trial among HIV infected patients initiating antiretroviral treatment.

SETTING

Three diverse healthcare delivery settings in south India: two ambulatory clinics within the Indian national programme and one private HIV healthcare clinic.

PARTICIPANTS

631 HIV infected, ART naïve, adult patients eligible to initiate first line ART were randomly assigned to mobile phone intervention (n=315) or standard care (n=316) and followed for 96 weeks..

INTERVENTION

The intervention consisted of customised, interactive, automated voice reminders, and a pictorial message that were sent weekly to the patients' mobile phones for the duration of the study.

MAIN OUTCOME MEASURES

The primary outcome was time to virological failure (viral load >400 copies/mL on two consecutive measurements). Secondary outcomes included ART adherence measured by pill count, death rate, and attrition rate. Suboptimal adherence was defined as mean adherence <95%.

RESULTS

Using an intention-to-treat approach we found no observed difference in time to virological failure between the allocation groups: failures in the intervention and standard care arms were 49/315 (15.6%) and 49/316 (15.5%) respectively (unadjusted hazard ratio 0.98, 95% confidence interval 0.67 to 1.47, P=0.95). The rate of virological failure in the intervention and standard care groups were 10.52 and 10.73 per 100 person years respectively. Comparison of suboptimal adherence was similar between both groups (unadjusted incidence rate ratio 1.24, 95% CI 0.93 to 1.65, P=0.14). Incidence proportion of patients with suboptimal adherence was 81/300 (27.0%) in the intervention arm and 65/299 (21.7%) in the standard care arm. The results of analyses adjusted for potential confounders were similar, indicating no significant difference between the allocation groups. Other secondary outcomes such as death and attrition rates, and subgroup analysis also showed comparable results across allocation groups.

CONCLUSIONS

In this multicentre randomised controlled trial among ART naïve patients initiating first line ART within the Indian national programme, we found no significant effect of the mobile phone intervention on either time to virological failure or ART adherence at the end of two years of therapy.Trial registration Current Controlled Trials ISRCTN79261738.

Improved virologic outcomes over time for HIV-infected patients on antiretroviral therapy in a cohort from Rio de Janeiro, 1997-2011

BACKGROUND

Previous cohort studies have demonstrated the beneficial effects of antiretroviral therapy (ART) on viral load suppression. We aimed to examine the factors associated with virologic suppression for HIV-infected patients on ART receiving care at the Evandro Chagas Clinical Research Institute, Oswaldo Cruz Foundation in Rio de Janeiro, Brazil.

METHODS

HIV-1 RNA levels and CD4+ T-cell counts at the date closest to midyear (1 July) were evaluated for 1,678 ART-naïve patients ≥ 18 years of age initiating ART between 1997 and 2010. The odds ratios (OR) and 95% confidence intervals (CI) for having an undetectable viral load (≤ 400 copies/mL) were estimated using generalized estimating equations regression models adjusted for clinical and demographic factors. Time-updated covariates included age, years since HIV diagnosis, hepatitis C diagnosis and ART interruptions.

RESULTS

Between 1997 and 2011, the proportion of patients with an undetectable viral load increased from 6% to 78% and the median [interquartile range] CD4+ T-cell count increased from 207 [162, 343] to 554 [382, 743] cells/μL. Pre-treatment median CD4+ T-cell count significantly increased over the observation period from 114 [37, 161] to 237 [76, 333] cells/μL (p < .001). The per-year adjusted OR (aOR) for having undetectable viral load was 1.18 (95% CI = 1.16-1.21). ART interruptions >1 month per calendar significantly decreased the odds [aOR = 0.32 (95% CI = 0.27-0.38)] of having an undetectable viral load. Patients initiating on a protease inhibitor (PI)-based first-line regimen were less likely to have undetectable viral load [aOR = 0.72 (95% CI = 0.63-0.83)] compared to those initiating on a non-nucleoside reverse transcriptase inhibitor (NNRTI)-based regimen.

CONCLUSIONS

Our results demonstrate significant improvements in virologic outcomes from 1997 to 2011, which persisted after adjusting for other factors. This may in part be due to improvements in care and new treatment options. NNRTI- versus PI-based first-line regimens were found to be associated with increased odds of having an undetectable viral load, consistent with previous studies. Treatment interruptions were found to be the most important determinant of not having an undetectable viral load. Studies are needed to characterize the reasons for treatment interruptions and to develop subsequent strategies for improving adherence to ART.

Factors associated with virological failure in a cohort of combination antiretroviral therapy-treated patients managed at a tertiary referral centre

BACKGROUND

Recent antiretroviral regimens are potent and better tolerated, resulting in a low prevalence of treatment failure. It is important to identify the drivers of virological failure, so that patients at risk can be identified early and prevention strategies implemented.

METHODS

We performed a retrospective case-control study of HIV-positive patients on antiretroviral therapy and managed at The Alfred Hospital during 2010 to evaluate the predictors of virological failure. Controls were matched 3:1 to cases by gender, and by clinical review in the same week as the diagnosis of virological failure in the case. Predictors of virological failure were identified by multivariate conditional logistic regression.

RESULTS

Thirty-nine patients were identified with treatment failure. In the multivariate model, characteristics associated with virological failure were missed clinic appointments in 1 year before virological failure (odds ratio (OR)=13.1, 95% confidence interval (CI): 2.8-61.1), multiple previous combined antiretroviral therapy regimens (OR =4.2, 95% CI:1.2-15.3), current hepatitis C infection (OR=8.6, 95% CI: 1.9-38.7), older age at HIV diagnosis (OR=1.1, 95% CI: 1.0-1.2), younger age at time of virological failure (OR=0.9, 95% CI: 0.8 to 1.0), and CD4 cell count at virological failure (OR=0.7, 95% CI: 0.5 to 0.9).

CONCLUSIONS

Targeted and appropriate adherence support should be provided to treatment-experienced patients, particularly those who have missed clinical appointments and those with hepatitis C coinfection. Further elucidation of the barriers to clinic attendance may optimise linkage and retention in care.

[Consensus Statement by GeSIDA/National AIDS Plan Secretariat on antiretroviral treatment in adults infected by the human immunodeficiency virus (Updated January 2013)]

OBJECTIVE

This consensus document is an update of combined antiretroviral therapy (cART) guidelines for HIV-1 infected adult patients.

METHODS

To formulate these recommendations a panel composed of members of the GeSIDA/National AIDS Plan Secretariat (Grupo de Estudio de Sida and the Secretaría del Plan Nacional sobre el Sida) reviewed the efficacy and safety advances in clinical trials, cohort and pharmacokinetic studies published in medical journals (PubMed and Embase) or presented in medical scientific meetings. The strength of the recommendations and the evidence which support them are based on a modification of the criteria of Infectious Diseases Society of America.

RESULTS

cART is recommended in patients with symptoms of HIV infection, in pregnant women, in serodiscordant couples with high risk of transmission, in hepatitisB co-infection requiring treatment, and in HIV nephropathy. cART is recommended in asymptomatic patients if CD4 is <500cells/μl. If CD4 are >500cells/μl cART should be considered in the case of chronic hepatitisC, cirrhosis, high cardiovascular risk, plasma viral load >100.000 copies/ml, proportion of CD4 cells <14%, neurocognitive deficits, and in people aged >55years. The objective of cART is to achieve an undetectable viral load. The first cART should include 2 reverse transcriptase inhibitors (RTI) nucleoside analogs and a third drug (a non-analog RTI, a ritonavir boosted protease inhibitor, or an integrase inhibitor). The panel has consensually selected some drug combinations, for the first cART and specific criteria for cART in acute HIV infection, in tuberculosis and other HIV related opportunistic infections, for the women and in pregnancy, in hepatitisB or C co-infection, in HIV-2 infection, and in post-exposure prophylaxis.

CONCLUSIONS

These new guidelines update previous recommendations related to first cART (when to begin and what drugs should be used), how to monitor, and what to do in case of viral failure or adverse drug reactions. cART specific criteria in comorbid patients and special situations are similarly updated.

The incidence of AIDS-defining illnesses at a current CD4 count ≥ 200 cells/μL in the post-combination antiretroviral therapy era

BACKGROUND

Few studies consider the incidence of individual AIDS-defining illnesses (ADIs) at higher CD4 counts, relevant on a population level for monitoring and resource allocation.

METHODS

Individuals from the Collaboration of Observational HIV Epidemiological Research Europe (COHERE) aged ≥14 years with ≥1 CD4 count of ≥200 µL between 1998 and 2010 were included. Incidence rates (per 1000 person-years of follow-up [PYFU]) were calculated for each ADI within different CD4 strata; Poisson regression, using generalized estimating equations and robust standard errors, was used to model rates of ADIs with current CD4 ≥500/µL.

RESULTS

A total of 12 135 ADIs occurred at a CD4 count of ≥200 cells/µL among 207 539 persons with 1 154 803 PYFU. Incidence rates declined from 20.5 per 1000 PYFU (95% confidence interval [CI], 20.0-21.1 per 1000 PYFU) with current CD4 200-349 cells/µL to 4.1 per 1000 PYFU (95% CI, 3.6-4.6 per 1000 PYFU) with current CD4 ≥ 1000 cells/µL. Persons with a current CD4 of 500-749 cells/µL had a significantly higher rate of ADIs (adjusted incidence rate ratio [aIRR], 1.20; 95% CI, 1.10-1.32), whereas those with a current CD4 of ≥1000 cells/µL had a similar rate (aIRR, 0.92; 95% CI, .79-1.07), compared to a current CD4 of 750-999 cells/µL. Results were consistent in persons with high or low viral load. Findings were stronger for malignant ADIs (aIRR, 1.52; 95% CI, 1.25-1.86) than for nonmalignant ADIs (aIRR, 1.12; 95% CI, 1.01-1.25), comparing persons with a current CD4 of 500-749 cells/µL to 750-999 cells/µL.

DISCUSSION

The incidence of ADIs was higher in individuals with a current CD4 count of 500-749 cells/µL compared to those with a CD4 count of 750-999 cells/µL, but did not decrease further at higher CD4 counts. Results were similar in patients virologically suppressed on combination antiretroviral therapy, suggesting that immune reconstitution is not complete until the CD4 increases to >750 cells/µL.

Predictors of first-line antiretroviral therapy discontinuation due to drug-related adverse events in HIV-infected patients: a retrospective cohort study

BACKGROUND

Drug-related toxicity has been one of the main causes of antiretroviral treatment discontinuation. However, its determinants are not fully understood. Aim of this study was to investigate predictors of first-line antiretroviral therapy discontinuation due to adverse events and their evolution in recent years.

METHODS

Patients starting first-line antiretroviral therapy were retrospectively selected. Primary end-point was the time to discontinuation of therapy due to adverse events, estimating incidence, fitting Kaplan-Meier and multivariable Cox regression models upon clinical/demographic/chemical baseline patients' markers.

RESULTS

1,096 patients were included: 302 discontinuations for adverse events were observed over 1,861 person years of follow-up between 1988 and 2010, corresponding to an incidence (95% CI) of 0.16 (0.14-0.18). By Kaplan-Meier estimation, the probabilities (95% CI) of being free from an adverse event at 90 days, 180 days, one year, two years, and five years were 0.88 (0.86-0.90), 0.85 (0.83-0.87), 0.79 (0.76-0.81), 0.70 (0.67-0.74), 0.55 (0.50-0.61), respectively. The most represented adverse events were gastrointestinal symptoms (28.5%), hematological (13.2%) or metabolic (lipid and glucose metabolism, lipodystrophy) (11.3%) toxicities and hypersensitivity reactions (9.3%). Factors associated with an increased hazard of adverse events were: older age, CDC stage C, female gender, homo/bisexual risk group (vs. heterosexual), HBsAg-positivity. Among drugs, zidovudine, stavudine, zalcitabine, didanosine, full-dose ritonavir, indinavir but also efavirenz (actually recommended for first-line regimens) were associated to an increased hazard of toxicity. Moreover, patients infected by HIV genotype F1 showed a trend for a higher risk of adverse events.

CONCLUSIONS

After starting antiretroviral therapy, the probability of remaining free from adverse events seems to decrease over time. Among drugs associated with increased toxicity, only one is currently recommended for first-line regimens but with improved drug formulation. Older age, CDC stage, MSM risk factor and gender are also associated with an increased hazard of toxicity and should be considered when designing a first-line regimen.

Time to virological failure, treatment change and interruption for individuals treated within 12 months of HIV seroconversion and in chronic infection

BACKGROUND

Estimates of treatment failure, change and interruption are lacking for individuals treated in early HIV infection.

METHODS

Using CASCADE data, we compared the effect of treatment in early infection (within 12 months of seroconversion) with that seen in chronic infection on risk of virological failure, change and interruption. Failure was defined as two subsequent measures of HIV RNA>1,000 copies/ml following suppression (<500 copies/ml), or >500 copies/ml 6 months following initiation. Treatment change and interruption were defined as modification or interruption lasting >1 week. In multivariable competing risks proportional subdistribution hazards models, we adjusted for combination antiretroviral therapy (cART) class, sex, risk group, age, CD4(+) T-cell count, HIV RNA and calendar period at treatment initiation.

RESULTS

Of 1,627 individuals initiating cART early (median 1.8 months from seroconversion), 159, 395 and 692 failed, changed and interrupted therapy, respectively. For 2,710 individuals initiating cART in chronic infection (median 35.9 months from seroconversion), the corresponding values were 266, 569 and 597. Adjusted hazard ratios (HRs; 95% CIs) for treatment failure and change were similar between the two treatment groups (0.93 [0.72, 1.20] and 1.06 [0.91, 1.24], respectively). There was an increasing trend in rates of interruption over calendar time for those treated early, and a decreasing trend for those starting treatment in chronic infection. Consequently, compared with chronic infection, treatment interruption was similar for early starters in the early cART period, but the relative hazard increased over calendar time (1.54 [1.33, 1.79] in 2000).

CONCLUSIONS

Individuals initiating treatment in early HIV infection are more likely to interrupt treatment than those initiating later. However, rates of failure and treatment change were similar between the two groups.

[Consensus document of Gesida and Spanish Secretariat for the National Plan on AIDS (SPNS) regarding combined antiretroviral treatment in adults infected by the human immunodeficiency virus (January 2012)]

This consensus document has been prepared by a panel consisting of members of the AIDS Study Group (Gesida) and the Spanish Secretariat for the National Plan on AIDS (SPNS) after reviewing the efficacy and safety results of clinical trials, cohort and pharmacokinetic studies published in medical journals, or presented in medical scientific meetings. Gesida has prepared an objective and structured method to prioritise combined antiretroviral treatment (cART) in naïve patients. Recommendations strength (A, B, C) and the evidence which supports them (I, II, III) are based on a modification of the Infectious Diseases Society of America criteria. The current antiretroviral treatment (ART) of choice for chronic HIV infection is the combination of three drugs. ART is recommended in patients with symptomatic HIV infection, in pregnancy, in serodiscordant couples with high transmission risk, hepatitis B fulfilling treatment criteria, and HIV nephropathy. Guidelines on ART treatment in patients with concurrent diagnosis of HIV infection and an opportunistic type C infection are included. In asymptomatic patients ART is recommended on the basis of CD4 lymphocyte counts, plasma viral load and patient co-morbidities, as follows: 1) therapy should be started in patients with CD4 counts <350 cells/μL; 2) when CD4 counts are between 350 and 500 cells/μL, therapy will be recommended and only delayed if patient is reluctant to take it, the CD4 are stabilised, and the plasma viral load is low; 3) therapy could be deferred when CD4 counts are above 500 cells/μL, but should be considered in cases of cirrhosis, chronic hepatitis C, high cardiovascular risk, plasma viral load >10(5) copies/mL, proportion of CD4 cells <14%, and in people aged >55 years. ART should include 2 reverse transcriptase inhibitors nucleoside analogues and a third drug (non-analogue reverse transcriptase inhibitor, ritonavir boosted protease inhibitor or integrase inhibitor). The panel has consensually selected and given priority to using the Gesida score for some drug combinations, some of them co-formulated. The objective of ART is to achieve an undetectable viral load. Adherence to therapy plays an essential role in maintaining antiviral response. Therapeutic options are limited after ART failures, but an undetectable viral load may be possible nowadays. Adverse events are a fading problem of ART. Guidelines in acute HIV infection, in women, in pregnancy, and to prevent mother-to-child transmission and pre- and post-exposition prophylaxis are commented upon. Management of hepatitis B or C co-infection, other co-morbidities, and the characteristics of ART in HIV-2 infection are included.

Factors associated with HIV-1 virological failure in an outpatient clinic for HIV-infected people in Haiphong, Vietnam

The objective of our study was to investigate factors associated with virological failure in 100 consecutive HIV-1 infected Vietnamese adults who initiated antiretroviral therapy (ART) from June 2007 to June 2008. Data were collected from medical records, and a structured questionnaire was used in individual interviews to investigate factors associated with adherence to ART. Plasma HIV viral load was measured at the time of the interview. The median age was 35 years, 35% were women and heterosexual intercourse was the most common mode of HIV transmission (61%). After a median of 14 months since starting ART, 23% had detectable HIV-1 viral load (≥ 400 copies/mL). Patients who had developed a World Health Organization (WHO) clinical stage 4 condition at the time of initiation of ART were more likely to experience virological failure than those in stages 1-3, odds ratio (OR): 5.20 (95% confidence interval [CI] 1.34-20.11), P = 0.017. Patients who reported that their health status was evaluated by a physician at each visit were less likely to experience virological failure, OR: 0.02 (95% CI 0.00-0.24), P = 0.002.

Projected life expectancy of people with HIV according to timing of diagnosis

BACKGROUND AND OBJECTIVES

Effective antiretroviral therapy (ART) has contributed greatly toward survival for people with HIV, yet many remain undiagnosed until very late. Our aims were to estimate the life expectancy of an HIV-infected MSM living in a developed country with extensive access to ART and healthcare, and to assess the effect of late diagnosis on life expectancy.

METHODS

A stochastic computer simulation model of HIV infection and the effect of ART was used to estimate life expectancy and determine the distribution of potential lifetime outcomes of an MSM, aged 30 years, who becomes HIV positive in 2010. The effect of altering the diagnosis rate was investigated.

RESULTS

Assuming a high rate of HIV diagnosis (median CD4 cell count at diagnosis, 432  cells/μl), projected median age at death (life expectancy) was 75.0 years. This implies 7.0 years of life were lost on average due to HIV. Cumulative risks of death by 5 and 10 years after infection were 2.3 and 5.2%, respectively. The 95% uncertainty bound for life expectancy was (68.0,77.3) years. When a low diagnosis rate was assumed (diagnosis only when symptomatic, median CD4 cell count 140  cells/μl), life expectancy was 71.5 years, implying an average 10.5 years of life lost due to HIV.

CONCLUSION

If low rates of virologic failure observed in treated patients continue, predicted life expectancy is relatively high in people with HIV who can access a wide range of antiretrovirals. The greatest risk of excess mortality is due to delays in HIV diagnosis.

Missing data on the estimation of the prevalence of accumulated human immunodeficiency virus drug resistance in patients treated with antiretroviral drugs in north america

Determination of the prevalence of accumulated antiretroviral drug resistance among persons infected with human immunodeficiency virus (HIV) is complicated by the lack of routine measurement in clinical care. By using data from 8 clinic-based cohorts from the North American AIDS Cohort Collaboration on Research and Design, drug-resistance mutations from those with genotype tests were determined and scored using the Genotypic Resistance Interpretation Algorithm developed at Stanford University. For each year from 2000 through 2005, the prevalence was calculated using data from the tested subset, assumptions that incorporated clinical knowledge, and multiple imputation methods to yield a complete data set. A total of 9,289 patients contributed data to the analysis; 3,959 had at least 1 viral load above 1,000 copies/mL, of whom 2,962 (75%) had undergone at least 1 genotype test. Using these methods, the authors estimated that the prevalence of accumulated resistance to 2 or more antiretroviral drug classes had increased from 14% in 2000 to 17% in 2005 (P < 0.001). In contrast, the prevalence of resistance in the tested subset declined from 57% to 36% for 2 or more classes. The authors' use of clinical knowledge and multiple imputation methods revealed trends in HIV drug resistance among patients in care that were markedly different from those observed using only data from patients who had undergone genotype tests.

Does HAART efficacy translate to effectiveness? Evidence for a trial effect

BACKGROUND

Patients who participate in clinical trials may experience better clinical outcomes than patients who initiate similar therapy within clinical care (trial effect), but no published studies have evaluated a trial effect in HIV clinical trials.

METHODS

To examine a trial effect we compared virologic suppression (VS) among patients who initiated HAART in a clinical trial versus in routine clinical care. VS was defined as a plasma HIV RNA ≤ 400 copies/ml at six months after HAART initiation and was assessed within strata of early (1996-99) or current (2000-06) HAART periods. Risk ratios (RR) were estimated using binomial models.

RESULTS

Of 738 persons initiating HAART, 30.6% were women, 61.7% were black, 30% initiated therapy in a clinical trial and 67% (n =  496) had an evaluable six month HIV RNA result. HAART regimens differed between the early and current periods (p < 0.001); unboosted PI regimens (55.6%) were more common in the early and NNRTI regimens (46.4%) were more common in the current period. Overall, 78% (95%CI 74, 82%) of patients achieved VS and trial participants were 16% more likely to achieve VS (unadjusted RR 1.16, 95%CI 1.06, 1.27). Comparing trial to non-trial participants, VS differed by study period. In the early period, trial participants initiating HAART were significantly more likely to achieve VS than non-trial participants (adjusted RR 1.33; 95%CI 1.15, 1.54), but not in the current period (adjusted RR 0.98; 95%CI 0.87, 1.11).

CONCLUSIONS

A clear clinical trial effect on suppression of HIV replication was observed in the early HAART period but not in the current period.

A prognostic model for estimating the time to virologic failure in HIV-1 infected patients undergoing a new combination antiretroviral therapy regimen

Background

HIV-1 genotypic susceptibility scores (GSSs) were proven to be significant prognostic factors of fixed time-point virologic outcomes after combination antiretroviral therapy (cART) switch/initiation. However, their relative-hazard for the time to virologic failure has not been thoroughly investigated, and an expert system that is able to predict how long a new cART regimen will remain effective has never been designed.

Methods

We analyzed patients of the Italian ARCA cohort starting a new cART from 1999 onwards either after virologic failure or as treatment-naïve. The time to virologic failure was the endpoint, from the 90^th day after treatment start, defined as the first HIV-1 RNA > 400 copies/ml, censoring at last available HIV-1 RNA before treatment discontinuation. We assessed the relative hazard/importance of GSSs according to distinct interpretation systems (Rega, ANRS and HIVdb) and other covariates by means of Cox regression and random survival forests (RSF). Prediction models were validated via the bootstrap and c-index measure.

Results

The dataset included 2337 regimens from 2182 patients, of which 733 were previously treatment-naïve. We observed 1067 virologic failures over 2820 persons-years. Multivariable analysis revealed that low GSSs of cART were independently associated with the hazard of a virologic failure, along with several other covariates. Evaluation of predictive performance yielded a modest ability of the Cox regression to predict the virologic endpoint (c-index≈0.70), while RSF showed a better performance (c-index≈0.73, p < 0.0001 vs. Cox regression). Variable importance according to RSF was concordant with the Cox hazards.

Conclusions

GSSs of cART and several other covariates were investigated using linear and non-linear survival analysis. RSF models are a promising approach for the development of a reliable system that predicts time to virologic failure better than Cox regression. Such models might represent a significant improvement over the current methods for monitoring and optimization of cART.

Adherence to drug-refill is a useful early warning indicator of virologic and immunologic failure among HIV patients on first-line ART in South Africa

BACKGROUND

Affordable strategies to prevent treatment failure on first-line regimens among HIV patients are essential for the long-term success of antiretroviral therapy (ART) in sub-Saharan Africa. WHO recommends using routinely collected data such as adherence to drug-refill visits as early warning indicators. We examined the association between adherence to drug-refill visits and long-term virologic and immunologic failure among non-nucleoside reverse transcriptase inhibitor (NNRTI) recipients in South Africa.

METHODS

In 2008, 456 patients on NNRTI-based ART for a median of 44 months (range 12-99 months; 1,510 person-years) were enrolled in a retrospective cohort study in Soweto. Charts were reviewed for clinical characteristics before and during ART. Multivariable logistic regression and Kaplan-Meier survival analysis assessed associations with virologic (two repeated VL>50 copies/ml) and immunologic failure (as defined by WHO).

RESULTS

After a median of 15 months on ART, 19% (n = 88) and 19% (n = 87) had failed virologically and immunologically respectively. A cumulative adherence of <95% to drug-refill visits was significantly associated with both virologic and immunologic failure (p<0.01). In the final multivariable model, risk factors for virologic failure were incomplete adherence (OR 2.8, 95%CI 1.2-6.7), and previous exposure to single-dose nevirapine or any other antiretrovirals (adj. OR 2.1, 95%CI 1.2-3.9), adjusted for age and sex. In Kaplan-Meier analysis, the virologic failure rate by month 48 was 19% vs. 37% among adherent and non-adherent patients respectively (logrank p value = 0.02).

CONCLUSION

One in five failed virologically after a median of 15 months on ART. Adherence to drug-refill visits works as an early warning indicator for both virologic and immunologic failure.

Increased vulnerability of rural children on antiretroviral therapy attending public health facilities in South Africa: a retrospective cohort study

BACKGROUND

A large proportion of the 340,000 HIV-positive children in South Africa live in rural areas, yet there is little sub-Saharan data comparing rural paediatric antiretroviral therapy (ART) programme outcomes with urban facilities. We compared clinical, immunological and virological outcomes between children at seven rural and 37 urban facilities across four provinces in South Africa.

METHODS

We conducted a retrospective cohort study of routine data of children enrolled on ART between November 2003 and March 2008 in three settings, namely: urban residence and facility attendance (urban group); rural residence and facility attendance (rural group); and rural residents attending urban facilities (rural/urban group). Outcome measures were: death, loss to follow up (LTFU), virological suppression, and changes in CD4 percentage and weight-for-age-z (WAZ) scores. Kaplan-Meier estimates, logrank tests, multivariable Cox regression and generalized estimating equation models were used to compare outcomes between groups.

RESULTS

In total, 2332 ART-naïve children were included, (1727, 228 and 377 children in the urban, rural and rural/urban groups, respectively). At presentation, rural group children were older (6.7 vs. 5.6 and 5.8 years), had lower CD4 cell percentages (10.0% vs. 12.8% and 12.7%), lower WAZ scores (-2.06 vs. -1.46 and -1.41) and higher proportions with severe underweight (26% vs.15% and 15%) compared with the urban and rural/urban groups, respectively. Mortality was significantly higher in the rural group and LTFU significantly increased in the rural/urban group. After 24 months of ART, mortality probabilities were 3.4% (CI: 2.4-4.8%), 7.7% (CI: 4.5-13.0%) and 3.1% (CI: 1.7-5.6%) p = 0.0137; LTFU probabilities were 11.5% (CI: 9.3-14.0%), 8.8% (CI: 4.5-16.9%) and 16.6% (CI: 12.4-22.6%), p = 0.0028 in the urban, rural and rural/urban groups, respectively. The rural group had an increased adjusted mortality probability, adjusted hazards ratio 2.41 (CI: 1.25-4.67) and the rural/urban group had an increased adjusted LTFU probability, aHR 2.85 (CI: 1.41-5.79). The rural/urban group had a decreased adjusted probability of virological suppression compared with the urban group at any timepoint on treatment, adjusted odds ratio 0.67 (CI: 0.48-0.93).

CONCLUSIONS

Rural HIV-positive children are a vulnerable group, exhibiting delayed access to ART and an increased risk of poor outcomes while on ART. Expansion of rural paediatric ART programmes, with future research exploring improvements to rural health system effectiveness, is required.

Better antiretroviral therapy outcomes at primary healthcare facilities: an evaluation of three tiers of ART services in four South African provinces

Background

There are conflicting reports of antiretroviral therapy (ART) effectiveness comparisons between primary healthcare (PHC) facilities and hospitals in low-income settings. This comparison has not been evaluated on a broad scale in South Africa.

Methodology/Principal Findings

A retrospective cohort study was conducted including ART-naïve adults from 59 facilities in four provinces in South Africa, enrolled between 2004 and 2007. Kaplan-Meier estimates, competing-risks Cox regression, generalised estimating equation population-averaged models and logistic regression were used to compare death, loss to follow-up (LTFU) and virological suppression (VS) between PHC, district and regional hospitals. 29 203 adults from 47 PHC facilities, nine district hospitals and three regional hospitals were included. Patients at PHC facilities had more advanced WHO stage disease when starting ART. Retention in care was 80.1% (95% CI: 79.3%–80.8%), 71.5% (95% CI: 69.1%–73.8%) and 68.7% (95% CI: 67.0%–69.7%) at PHC, district and regional hospitals respectively, after 24 months of treatment (P<0.0001). In adjusted regression analyses, LTFU was independently increased at regional hospitals (aHR 2.19; 95% CI: 1.94−2.47) and mortality was independently elevated at district hospitals (aHR 1.60; 95% CI: 1.30−1.99) compared to PHC facilities after 12 months of ART. District and regional hospital patients had independently reduced probabilities of VS, aOR 0.76 (95% CI: 0.59−0.97) and 0.64 (95% CI: 0.56−0.75) respectively compared to PHC facilities over 24 months of treatment.

Conclusions/Significance

ART outcomes were superior at PHC facilities, despite PHC patients having more advanced clinical stage disease when starting ART, suggesting that ART can be adequately provided at this level and supporting the South African government's call for rapid up-scaling of ART at the primary level of care. Further prospective research is required to determine the degree to which outcome differences are attributable to either facility level characteristics or patient co-morbidity at hospital level.

Assessing the performance of a computer-based policy model of HIV and AIDS

Background

Model-based analyses, conducted within a decision analytic framework, provide a systematic way to combine information about the natural history of disease and effectiveness of clinical management strategies with demographic and epidemiological characteristics of the population. Among the challenges with disease-specific modeling include the need to identify influential assumptions and to assess the face validity and internal consistency of the model.

Methods and Findings

We describe a series of exercises involved in adapting a computer-based simulation model of HIV disease to the Women's Interagency HIV Study (WIHS) cohort and assess model performance as we re-parameterized the model to address policy questions in the U.S. relevant to HIV-infected women using data from the WIHS. Empiric calibration targets included 24-month survival curves stratified by treatment status and CD4 cell count. The most influential assumptions in untreated women included chronic HIV-associated mortality following an opportunistic infection, and in treated women, the ‘clinical effectiveness’ of HAART and the ability of HAART to prevent HIV complications independent of virologic suppression. Good-fitting parameter sets required reductions in the clinical effectiveness of 1^st and 2^nd line HAART and improvements in 3^rd and 4^th line regimens. Projected rates of treatment regimen switching using the calibrated cohort-specific model closely approximated independent analyses published using data from the WIHS.

Conclusions

The model demonstrated good internal consistency and face validity, and supported cohort heterogeneities that have been reported in the literature. Iterative assessment of model performance can provide information about the relative influence of uncertain assumptions and provide insight into heterogeneities within and between cohorts. Description of calibration exercises can enhance the transparency of disease-specific models.

Incidence of modifying or discontinuing first HAART regimen and its determinants in a cohort of HIV-infected patients from Rio de Janeiro, Brazil

Studies on the long-term safety and tolerability of HAART are scarce in developing countries. HAART has been universally available in Brazil since 1997, providing a unique opportunity to evaluate the incidence and risk factors for HAART discontinuation or modification. We analyzed retrospective data from 670 treatment-naive patients followed at the HIV cohort of Evandro Chagas Clinical Research Institute, Oswaldo Cruz Foundation, in Rio de Janeiro, Brazil, who first received HAART between January 1996 and December 2006. Our four outcomes of interest were treatment failure (TF-MOD), short-term toxicity (ST-MOD), long-term toxicity (LT-MOD), and overall modification/discontinuation (MOD, composed of TF-MOD, ST-MOD, LT-MOD, and other reasons). Risk factors were assessed using Cox's proportional hazards regression. Incidences of MOD, ST-MOD, LT-MOD, and TF-MOD were 28.3, 24.0, 4.0, and 5.6 per 100 persons-years, respectively. MOD was observed in 69% of the patients; 40% of the MODs were toxicity related. The risk of MOD in the first year of treatment was 32% (95% CI: 28.3-35.5%); the median time from HAART initiation to MOD was 14 months (IQR: 3.0-29.5). The most frequent reasons for ST-MOD were gastrointestinal; women had a higher hazard for ST-MOD. Metabolic toxicity was the most frequent reason for LT- MOD, particularly dislipidemia and lipodystrophy. Increased hazard of TF-MOD was observed among those with lower CD4(+) lymphocyte counts (<200 cells/mm(3)). Our results indicate that toxicities can compromise adherence and thus impact future treatment options. This is especially relevant in the context of limited access to second and third line treatment regimens.

[AIDS Study Group/Spanish AIDS Plan consensus document on antiretroviral therapy in adults with human immunodeficiency virus infection (updated January 2010)]

OBJECTIVE

This consensus document is an update of antiretroviral therapy recommendations for adult patients with human immunodeficiency virus infection.

METHODS

To formulate these recommendations a panel made up of members of the Grupo de Estudio de Sida (Gesida, AIDS Study Group) and the Plan Nacional sobre el Sida (PNS, Spanish AIDS Plan) reviewed the advances in the current understanding of the pathophysiology of human immunodeficiency virus (HIV) infection, the efficacy and safety of clinical trials, and cohort and pharmacokinetic studies published in biomedical journals or presented at scientific meetings. Three levels of evidence were defined according to the data source: randomized studies (level A), cohort or case-control studies (level B), and expert opinion (level C). The decision to recommend, consider or not to recommend ART was established in each situation.

RESULTS

Currently, the treatment of choice for chronic HIV infection is the combination of three drugs of two different classes, including 2 nucleosides or nucleotide analogs (NRTI) plus 1 non-nucleoside (NNRTI) or 1 boosted protease inhibitor (PI/r), but other combinations are possible. Initiation of ART is recommended in patients with symptomatic HIV infection. In asymptomatic patients, initiation of ART is recommended on the basis of CD4 lymphocyte counts, plasma viral load and patient co-morbidities, as follows: 1) therapy should be started in patients with CD4 counts below 350 cells/microl; 2) When CD4 counts are between 350 and 500 cells/microl, therapy should be started in case of cirrhosis, chronic hepatitis C, high cardiovascular risk, HIV nephropathy, HIV viral load above 100,000 copies/ml, proportion of CD4 cells under 14%, and in people aged over 55; 3) Therapy should be deferred when CD4 are above 500 cells/microl, but could be considered if any of previous considerations concurs. Treatment should be initiated in case of hepatitis B requiring treatment and should be considered for reduce sexual transmission. The objective of ART is to achieve an undetectable viral load. Adherence to therapy plays an essential role in maintaining antiviral response. Therapeutic options are limited after ART failures but undetectable viral loads maybe possible with the new drugs even in highly drug experienced patients. Genotype studies are useful in these situations. Drug toxicity of ART therapy is losing importance as benefits exceed adverse effects. Criteria for antiretroviral treatment in acute infection, pregnancy and post-exposure prophylaxis are mentioned as well as the management of HIV co-infection with hepatitis B or C.

CONCLUSIONS

CD4 cells counts, viral load and patient co-morbidities are the most important reference factors to consider when initiating ART in asymptomatic patients. The large number of available drugs, the increased sensitivity of tests to monitor viral load, and the ability to determine viral resistance is leading to a more individualized therapy approach in order to achieve undetectable viral load under any circumstances.

Design of a randomized trial to evaluate the influence of mobile phone reminders on adherence to first line antiretroviral treatment in South India--the HIVIND study protocol

BACKGROUND

Poor adherence to antiretroviral treatment has been a public health challenge associated with the treatment of HIV. Although different adherence-supporting interventions have been reported, their long term feasibility in low income settings remains uncertain. Thus, there is a need to explore sustainable contextual adherence aids in such settings, and to test these using rigorous scientific designs. The current ubiquity of mobile phones in many resource-constrained settings, make it a contextually appropriate and relatively low cost means of supporting adherence. In India, mobile phones have wide usage and acceptability and are potentially feasible tools for enhancing adherence to medications. This paper presents the study protocol for a trial, to evaluate the influence of mobile phone reminders on adherence to first-line antiretroviral treatment in South India.

METHODS/DESIGN

600 treatment naïve patients eligible for first-line treatment as per the national antiretroviral treatment guidelines will be recruited into the trial at two clinics in South India. Patients will be randomized into control and intervention arms. The control arm will receive the standard of care; the intervention arm will receive the standard of care plus mobile phone reminders. Each reminder will take the form of an automated call and a picture message. Reminders will be delivered once a week, at a time chosen by the patient. Patients will be followed up for 24 months or till the primary outcome i.e. virological failure, is reached, whichever is earlier. Self-reported adherence is a secondary outcome. Analysis is by intention-to-treat. A cost-effectiveness study of the intervention will also be carried out.

DISCUSSION

Stepping up telecommunications technology in resource-limited healthcare settings is a priority of the World Health Organization. The trial will evaluate if the use of mobile phone reminders can influence adherence to first-line antiretrovirals in an Indian context.

History of viral suppression on combination antiretroviral therapy as a predictor of virological failure after a treatment change

OBJECTIVES

HIV-infected persons experience different patterns of viral suppression after initiating combination antiretroviral therapy (cART). The relationship between such differences and risk of virological failure after starting a new antiretroviral could help with patient monitoring strategies.

METHODS

A total of 1827 patients on cART starting at least one new antiretroviral from 1 January 2000 while maintaining a suppressed viral load were included in the analysis. Poisson regression analysis identified factors predictive of virological failure after baseline in addition to traditional demographic variables. Baseline was defined as the date of starting new antiretrovirals.

RESULTS

Four hundred and fifty-one patients (24.7%) experienced virological failure, with an incidence rate (IR) of 7.3 per 100 person-years of follow-up (PYFU) [95% confidence interval (CI) 6.7-8.0]. After adjustment, patients who had rebounded in the year prior to baseline had a 2.4-times higher rate of virological failure after baseline (95% CI 1.77-3.26; P<.0001), while there was no increased incidence in patients whose last viral rebound was >3 years prior to baseline [Incidence rate ratio (IRR) 1.06; 95% CI 0.75-1.50; P=0.73] compared with patients who had never virally rebounded. Patients had an 86% (95% CI 1.36-2.55; P<.0001), 53% (95% CI 1.06-2.04; P=0.02) and 5% (95% CI 0.80-1.38; P=0.72) higher virological failure rate after baseline if they were virally suppressed <50%, 50-70% and 70-90% of the time they were on cART prior to baseline, respectively, compared with those virally suppressed >90% of the time.

DISCUSSION

Intensive monitoring after a treatment switch is required in patients who have rebounded recently or have a low percentage of time suppressed while on cART. Consideration should be given to increasing the provision of adherence counselling.

Trends in multidrug treatment failure and subsequent mortality among antiretroviral therapy-experienced patients with HIV infection in North America

BACKGROUND

Although combination antiretroviral therapy continues to evolve, with potentially more effective options emerging each year, the ability of therapy to prevent multiple regimen failure and mortality in clinical practice remains poorly defined.

METHODS

Sixteen cohorts representing over 60 sites contributed data on all individuals who initiated combination antiretroviral therapy. We identified those individuals who experienced virologic failure (defined as a human immunodeficiency virus [HIV] RNA level >1000 copies/mL), received modified therapy, and subsequently had a second episode of virologic failure. Multivariate Cox regression was used to assess factors associated with time to second regimen failure and the time to death after the onset of second regimen failure.

RESULTS

Of the 42,790 individuals who received therapy, 7159 experienced a second virologic failure. The risk of second virologic failure decreased from 1996 (56 cases per 100 person-years) through 2005 (16 cases per 100 person-years; P < .001). The cumulative mortality after onset of second virologic failure was 26% at 5 years and decreased over time. A history of AIDS, a lower CD4(+) T cell count, and a higher plasma HIV RNA level were each independently associated with mortality. Similar trends were observed when analysis was limited to the subset of previously treatment-naive patients

CONCLUSIONS

Although the rates of multiple regimen failure have decreased dramatically over the past decade, mortality rates for those who have experienced failure of at least 2 regimens have remained high. Plasma HIV RNA levels, CD4(+) T cell counts at time of treatment failure, and a history of AIDS remain independent risk factors for death, which emphasizes that these factors remain important targets for those in need of more-aggressive therapeutic interventions.

Impact of previous virological treatment failures and adherence on the outcome of antiretroviral therapy in 2007

Background

Combination antiretroviral treatment (cART) has been very successful, especially among selected patients in clinical trials. The aim of this study was to describe outcomes of cART on the population level in a large national cohort.

Methods

Characteristics of participants of the Swiss HIV Cohort Study on stable cART at two semiannual visits in 2007 were analyzed with respect to era of treatment initiation, number of previous virologically failed regimens and self reported adherence. Starting ART in the mono/dual era before HIV-1 RNA assays became available was counted as one failed regimen. Logistic regression was used to identify risk factors for virological failure between the two consecutive visits.

Results

Of 4541 patients 31.2% and 68.8% had initiated therapy in the mono/dual and cART era, respectively, and been on treatment for a median of 11.7 vs. 5.7 years. At visit 1 in 2007, the mean number of previous failed regimens was 3.2 vs. 0.5 and the viral load was undetectable (<50 copies/ml) in 84.6% vs. 89.1% of the participants, respectively. Adjusted odds ratios of a detectable viral load at visit 2 for participants from the mono/dual era with a history of 2 and 3, 4, >4 previous failures compared to 1 were 0.9 (95% CI 0.4–1.7), 0.8 (0.4–1.6), 1.6 (0.8–3.2), 3.3 (1.7–6.6) respectively, and 2.3 (1.1–4.8) for >2 missed cART doses during the last month, compared to perfect adherence. From the cART era, odds ratios with a history of 1, 2 and >2 previous failures compared to none were 1.8 (95% CI 1.3–2.5), 2.8 (1.7–4.5) and 7.8 (4.5–13.5), respectively, and 2.8 (1.6–4.8) for >2 missed cART doses during the last month, compared to perfect adherence.

Conclusions

A higher number of previous virologically failed regimens, and imperfect adherence to therapy were independent predictors of imminent virological failure.

Early antiretroviral therapy: the role of cohorts

PURPOSE OF REVIEW

To review the data that contribute to the debate on the optimal time to initiate highly active antiretroviral therapy in HIV-infected individuals, with a focus on the information that is available from cohort studies.

RECENT FINDINGS

The findings from cohort studies generally support initiation of highly active antiretroviral therapy at CD4 cell counts more than 350 cells/microl. In particular, the findings that death rates among treated HIV-infected individuals are higher than those in the general population, and that the risks of AIDS and serious non-AIDS events are higher in those with lower CD4 cell counts (even when the count remains >350 cells/microl), suggest that earlier initiation of highly active antiretroviral therapy may prevent some excess morbidity and mortality. However, given the lack of adjustment for lead-time bias in many analyses, the potential for residual confounding and the possible incomplete ascertainment of relevant outcomes in cohorts, it cannot be concluded that the benefits of highly active antiretroviral therapy when started at higher CD4 cell counts will outweigh the possible detrimental effects.

SUMMARY

Whereas the data from cohort studies currently support initiation of highly active antiretroviral therapy at CD4 cell counts more than 350 cells/microl, there is an urgent need for data from randomized trials to inform this decision.

Improvements in antiretroviral therapy outcomes over calendar time

PURPOSE OF REVIEW

The introduction of combination antiretroviral therapy (cART) led to substantial reductions in HIV-associated morbidity and mortality. However, the regimens in the early cART era were cumbersome and toxic. The introduction of new ART agents, fixed-dose combinations and novel strategies for cART delivery such as ritonavir 'boosting' of HIV-protease inhibitors have led to a perception of improvements in the tolerability and durability of contemporary cART regimens. It is in turn assumed that these developments have led to improved outcomes in the latter era of cART.

RECENT FINDINGS

Both cohort studies and randomized clinical trials suggest improvements in cART outcomes over calendar time. Key associated factors include reduced pill burden and dosing interval and improved tolerability and reduced toxicity of newer ART. A critical appreciation of the association between ART adherence and regimen durability has been important. Cohorts in recent times have included more patients who are completely ART-naïve at therapy initiation.

SUMMARY

The prognosis of HIV infection in developed countries is in the order of 40 years after cART initiation. An appreciation of the factors associated with long-term control of HIV viraemia is essential for the optimal management of the HIV-infected individual in contemporary practice.

Early treatment of HIV: implications for resource-limited settings

PURPOSE OF REVIEW

We review the current literature supporting adoption of higher CD4 thresholds for initiation of antiretroviral treatment and survey progress in adoption of early treatment policies in resource-limited settings. We highlight some of the challenges and opportunities implementation of early treatment will bring.

RECENT FINDINGS

The initial success of combination antiretroviral treatment resulted in the recommendation to treat early all individuals with HIV. However, the gradual realization that antiretroviral treatment was associated with toxicity led to a more tempered approach. Recent cohort studies and some clinical trials have shown that delaying treatment is associated with increased morbidity and mortality.

SUMMARY

Early treatment is routinely practiced in developed countries. Now, early treatment is being adopted as a strategy in many resource-limited settings. The implications of this policy shift are not known, but we predict early treatment will have important consequences for the health system, the individual, and the community. Whereas these consequences will bring significant challenges, the increased numbers of HIV-infected individuals on treatment will result in many new opportunities - antiretroviral treatment will become less expensive, systems to deliver chronic care will be strengthened, and the policy shift will focus greater attention on pregnant women and children. Finally, some authors postulate that early treatment may impact HIV transmission.

Timing of initiation of antiretroviral therapy in AIDS-free HIV-1-infected patients: a collaborative analysis of 18 HIV cohort studies

BACKGROUND

The CD4 cell count at which combination antiretroviral therapy should be started is a central, unresolved issue in the care of HIV-1-infected patients. In the absence of randomised trials, we examined this question in prospective cohort studies.

METHODS

We analysed data from 18 cohort studies of patients with HIV. Antiretroviral-naive patients from 15 of these studies were eligible for inclusion if they had started combination antiretroviral therapy (while AIDS-free, with a CD4 cell count less than 550 cells per microL, and with no history of injecting drug use) on or after Jan 1, 1998. We used data from patients followed up in seven of the cohorts in the era before the introduction of combination therapy (1989-95) to estimate distributions of lead times (from the first CD4 cell count measurement in an upper range to the upper threshold of a lower range) and unseen AIDS and death events (occurring before the upper threshold of a lower CD4 cell count range is reached) in the absence of treatment. These estimations were used to impute completed datasets in which lead times and unseen AIDS and death events were added to data for treated patients in deferred therapy groups. We compared the effect of deferred initiation of combination therapy with immediate initiation on rates of AIDS and death, and on death alone, in adjacent CD4 cell count ranges of width 100 cells per microL.

FINDINGS

Data were obtained for 21 247 patients who were followed up during the era before the introduction of combination therapy and 24 444 patients who were followed up from the start of treatment. Deferring combination therapy until a CD4 cell count of 251-350 cells per microL was associated with higher rates of AIDS and death than starting therapy in the range 351-450 cells per microL (hazard ratio [HR] 1.28, 95% CI 1.04-1.57). The adverse effect of deferring treatment increased with decreasing CD4 cell count threshold. Deferred initiation of combination therapy was also associated with higher mortality rates, although effects on mortality were less marked than effects on AIDS and death (HR 1.13, 0.80-1.60, for deferred initiation of treatment at CD4 cell count 251-350 cells per microL compared with initiation at 351-450 cells per microL).

INTERPRETATION

Our results suggest that 350 cells per microL should be the minimum threshold for initiation of antiretroviral therapy, and should help to guide physicians and patients in deciding when to start treatment.

Stability of antiretroviral regimens in patients with viral suppression

OBJECTIVE

To study the rate of treatment change due to toxicities in patients who achieved viral suppression within 6 months of starting antiretroviral therapy and who have never experienced virological failure.

METHODS

Included patients attended the Royal Free Hospital in London, started antiretroviral therapy in 2000-2005, and achieved viral suppression within 6 months. Included follow-up (censored at virological failure) was spent on a regimen of lamivudine or emtricitabine, with a second nucleoside/nucleotide reverse transcriptase inhibitor, and either a protease inhibitor or a nonnucleoside reverse transcriptase inhibitor.

RESULTS

In 912 person-years, there were 140 treatment changes due to toxicities (rate = 15.4 per 100 person-years, confidence interval = 12.8-17.9). In the multivariable analysis, factors associated with a higher rate of treatment change due to toxicities included increased age (for every 10 years increase: incidence rate ratio = 1.28, confidence interval = 1.04-1.57), being on stavudine compared with zidovudine (incidence rate ratio = 2.04, confidence interval = 1.28-3.26), and being on lopinavir compared with efavirenz (incidence rate ratio = 1.55, confidence interval = 1.04-2.31), whereas factors associated with a lower rate were being on tenofovir compared with zidovudine (incidence rate ratio = 0.46, confidence interval = 0.29-0.73), and being on atazanavir compared with efavirenz (incidence rate ratio = 0.23, confidence interval = 0.06-0.91).

CONCLUSIONS

In patients who have never experienced virological failure, the rate of treatment change due to toxicities is low, and certain regimens are associated with an even lower rate of change. If virological failure is avoided, some regimens are so far proving to be sufficiently stable to suggest that very long-term use is potentially feasible.

An audit of viral load in one clinical population to describe features of viraemic patients on antiretroviral therapy

OBJECTIVES

To assess the prevalence of an undetectable viral load (VL) (<50 HIV-1 RNA copies/mL) in a clinical population and to identify those viraemic and at risk of failing antiretroviral therapy (ART).

METHODS

An audit of a complete clinical population on 1 January 2005 via a clinical database and clinical note review.

RESULTS

On 1 January 2005, 1910 patients were under care; 1229/1332 (92%) of those exposed to ART for >16 weeks had a VL of <50 copies/mL. We examined 49/56 case notes of viraemic patients to identify explanations for viraemia. Common reasons included previous initial mono- or dual therapy, adherence problems, more advanced HIV disease, concomitant medications, physical and mental health issues and being less well linked into the service. A review of these patients' current status on 1 April 2007 showed that six of the 49 had since died. However, of those still alive, 20 (47%) had a VL <500 copies/mL.

CONCLUSIONS

The proportion of patients on ART with detectable viraemia is low in current clinical practice. New drugs may help those who are failing because of resistance. However, there is a small minority of patients who, for various reasons, appear unable to maintain sufficient adherence to ART.

[New therapeutic options in protracted HIV-infected patients with virological failure]

Once patients have a triple class virological failure, their treatment options are limited and there is an increased risk of death. In order to construct active treatment regimens, new potent antiretroviral agents are available for these patients. The virological target in patients with treatment failure is now plasma HIV RNA level below 50 copies/ml when 2 or more potent drugs are identified. If at least two active drugs cannot be identified, the current regimen should be maintained until new drugs become available, assuming that there is an immunological and clinical stability, in order to avoid the use of a single-active drug that usually leads to rapid development of resistance, further limiting the future treatment options. In this article, the current state of knowledge about these new agents available and the guidelines of main societies are reviewed.

HIV diagnosis at CD4 count above 500 cells/mm3 and progression to below 350 cells/mm3 without antiretroviral therapy

A trial to evaluate the risks and benefits of initiation of antiretroviral therapy (ART) in patients with high CD4 count (eg, > or =500 cells/mm3), in comparison with deferral (eg, to <350 cells/mm3), merits consideration. Two issues for consideration in designing such a trial are the proportion of patients seen in clinics who present with high CD4 count and the time it will take for those randomized to deferring ART to reach a level where ART must be initiated. Among 13,572 patients in the UK CHIC Study presenting since 1996, 3631 (27%) had a count > or =500 cells/mm3. Among 4268 ART-naive patients with at least one CD4 count in the 500 to 650 cells/mm3 range, the median time to <350 cells/mm3 (or start of ART) was 2.5 years, with a range of 2.1 to 3.1 years depending on the analysis approach. Viral load at baseline was a strong predictor of the time taken for the CD4 count to reach <350 cells/mm3, with the median ranging from 0.7 years in those with viral load > or =500,000 copies/mL to 4.7 years in those with <1000 copies/mL. This provides timely background data on ART-naive patients seen in clinical practice to support design of a trial to compare immediate with deferred ART in people with high CD4 count.

Translating efficacy into effectiveness in antiretroviral therapy: beyond the pill count

Durable and sustained suppression of HIV replication can be achieved as demonstrated in several recent clinical trials of antiretroviral (ARV) regimens. However, the efficacy demonstrated in the experimental setting does not always translate to effectiveness in the clinical setting. The frequency and number of medications (conventionally referred to as the pill count) contribute to regimen effectiveness. However, clinicians and HIV-infected patients recognise that there are several other characteristics of an ARV regimen that are equally important contributors to its effectiveness. Potency and durability, the potential for drug-drug interactions, and the occurrence of adverse events also contribute to the effectiveness and complexity of a drug regimen. A comprehensive consideration of factors associated with efficacy will optimise the translation to effectiveness for the individual infected with HIV.