Search

Background The World Health Organization recommends continuation with the failing second-line regimen if third-line option is not available. We investigated treatment outcomes among people living with HIV in Asia who continued with failing second-line regimens compared with those who had treatment modifications after failure.Methods Treatment modification was defined as a change of two antiretrovirals, a drug class change or treatment interruption (TI), all for >14 days. We assessed factors associated with CD4 changes and undetectable viral load (UVL <1,000 copies/ml) at 1 year after second-line failure using linear and logistic regression, respectively. Survival time was analysed using competing risk regression.Results Of the 328 patients who failed second-line ART in our cohorts, 208 (63%) had a subsequent treatment modification. Compared with those who continued the failing regimen, the average CD4 cell increase was higher in patients who had a modification without TI (difference =77.5, 95% CI 35.3, 119.7) while no difference was observed among those with TI (difference =-5.3, 95% CI -67.3, 56.8). Compared with those who continued the failing regimen, the odds of achieving UVL was lower in patients with TI (OR=0.18, 95% CI 0.06, 0.60) and similar among those who had a modification without TI (OR=1.97, 95% CI 0.95, 4.10), with proportions of UVL 60%, 22% and 75%, respectively. Survival time was not affected by treatment modifications.Conclusions CD4 cell improvements were observed in those who had treatment modification without TI compared with those on the failing regimen. When no other options are available, maintaining the same failing ART combination provided better VL control than interrupting treatment.

Background Comprehensive treatment and clinical management are central to improving outcomes for people living with HIV (PLHIV). We explored trends in HIV clinical care, treatment outcomes, and chronic kidney disease (CKD) and diabetes monitoring.Methods We included patients ≥18 years in care at ten clinical sites in eight Asian countries. Proportions of patients on antiretroviral therapy (ART), with annual viral load, and with viral load suppression (VLS; <1,000 copies/ml) were estimated by year for 2011– 2016, stratified by country income level (lower-middle income [LMIC] and high-income countries [HIC]). Among those on ART in 2016 we evaluated factors associated with annual CKD and diabetes monitoring.Results Among 31,346 patients (67% male), the proportions of patients on ART (median ART initiation year 2011, IQR 2007–2013), with annual viral load and VLS had substantially increased by 2016 (to 94%, 42% and 92%, respectively, in LMIC and 95%, 97% and 93%, respectively, in HIC) with the larger increases over time seen in LMIC. Among those on ART in 2016, monitoring proportions in LMIC were 53% for CKD and 26% for diabetes compared with 83% and 59%, respectively, in HIC. Overall, a decreased odds of monitoring was observed for male gender, heterosexual HIV exposure, no viral load and LMIC. Diabetes monitoring was also decreased in those with viral failure.Conclusions Our findings highlight suboptimal monitoring of viral load, CKD and diabetes in PLHIV in Asia. There is a need for affordable and scalable monitoring options to improve the joint care for HIV and non-communicable diseases.

Background We aimed to project the 10-year future incidence of cardiovascular disease (CVD) and model several intervention scenarios based on a multi-site Asian HIV-positive cohort.Methods Analyses were based on patients recruited to the TREAT Asia HIV Observational Database (TAHOD), consisting of 21 sites in 12 countries. Patients on triple antiretroviral therapy (ART) were included if they were alive, without previous CVD, and had data on CVD risk factors. Annual new CVD events for 2019–2028 were estimated with the D:A:D equation, accounting for age- and sex-adjusted mortality. Modelled intervention scenarios were treatment of high total cholesterol, low high-density lipoprotein cholesterol (HDL) or high blood pressure, abacavir or lopinavir substitution, and smoking cessation.Results Of 3,703 included patients, 69% were male, median age was 46 (IQR 40–53) years and median time since ART initiation was 9.8 years (IQR 7.5–14.1). Cohort incidence rates of CVD were projected to increase from 730 per 100,000 person-years (pys) in 2019 to 1,432 per 100,000 pys in 2028. In the modelled intervention scenarios, most events can be avoided by smoking cessation, abacavir substitution, lopinavir substitution, decreasing total cholesterol, treating high blood pressure and increasing HDL.Conclusions Our projections suggest a doubling of CVD incidence rates in Asian HIV-positive adults in our cohort. An increase in CVD can be expected in any ageing population, however, according to our models, this can be close to averted by interventions. Thus, there is an urgent need for risk screening and integration of HIV and CVD programmes to reduce the future CVD burden.

Background Loss to follow-up (LTFU) is a crucial indicator to evaluate the effectiveness of HIV care and treatment programmes. We assessed the LTFU rate and associated factors of Thai HIV-infected patients who enrolled in the National AIDS Program (NAP) for two periods: prior to (pre-ART) and after starting ART (ART-patients).Methods Thai HIV patients aged =15 years enrolled in NAP from 2008 to 2014. Vital status was ascertained by linkage with the National Death Registry. Competing risk models were used to calculate the adjusted sub-distribution hazards (aSHR) for LTFU for pre-ART and ART-patients, with death considered as a competing risk.Results A total of 157,026 patients registered in care and were included in analyses. The cumulative incidence of LTFU in pre-ART patients at 1 year was 10.2%, whereas in ART-patients it was 12.8%. Among pre-ART patients, younger age (<30 versus =45 years, aSHR 1.60, 95% CI 1.49, 1.72), less advanced HIV stage (aSHR 1.29, 95% CI 1.21, 1.37) and higher CD4+T-cell count (=350 versus <100, aSHR 6.31, 95% CI 5.74, 6.95) had a higher chance of LTFU. ART-patients with high baseline CD4+T-cell count (CD4 =350 versus CD4 <50, aSHR 2.06, 95% CI 1.97, 2.15) and non-advanced HIV stage had increased risk of LTFU.Conclusions Our findings provide new evidence of the LTFU rate in Thai HIV-infected patients in NAP. Emphasis needs to be placed on improving follow-up in all patients with higher CD4+T-cell counts. LTFU will be important to monitor as programmes move to commence ART regardless of CD4+T-cell count.

Background In the era of effective antiretroviral treatment (ART) CD4:CD8 ratio is proposed as a potential marker for HIV-positive (HIV+) patients at increased risk for non-AIDS comorbidities. The current study aims to compare CD4:CD8 ratio between Asian and Caucasian HIV+ patients.Methods HIV+ patients from the Australian HIV Observational Database (AHOD) and the TREAT Asia HIV Observational Database (TAHOD) meeting specific criteria were included. In these analyses Asian and Caucasian status were defined by cohort. Factors associated with a low CD4:CD8 ratio (cutoff <0.2) prior to ART commencement, and with achieving a normal CD4:CD8 ratio (>1) at 12 and 24 months post ART commencement were assessed using logistic regression.Results There were 591 patients from AHOD and 2,620 patients from TAHOD who met the inclusion criteria. TAHOD patients had a significantly (P<0.001) lower odds of having a baseline (prior to ART initiation) CD4:CD8 ratio greater than 0.2. After 12 months of ART, AHOD patients were more than twice as likely to achieve a normal CD4:CD8 ratio compared to TAHOD patients (15% versus 6%). However, after adjustment for confounding factors there was no significant difference between cohorts in the odds of achieving a CD4:CD8 ratio >1 (P=0.475).Conclusions We found a significantly lower CD4:CD8 ratio prior to commencing ART in TAHOD compared to AHOD even after adjusting for confounders. However, after adjustment, there was no significant difference between the cohorts in odds of achieving normal ratio. Baseline CD4+and CD8+counts seem to be the main driver for this difference between these two populations.

Background Access to combination antiretroviral therapy (cART) has decreased mortality in HIV-positive people. We aimed to estimate the expected additional years of life in HIV-positive Thai people after starting cART through the National AIDS Program (NAP), administered by the Thai National Health Security Office (NHSO).Methods The NHSO database collects characteristics of all Thai HIV-infected patients through the National AIDS Program, including linkage with the National Death Registry for vital status. This study included patients aged =15 years at cART initiation between 2008 and 2014. The abridged life table method was used to construct life tables stratified by sex and baseline CD4+T-cell count. Life expectancy was defined as the additional years of life from age at starting cART.Results 201,688 eligible patients were included in analyses, contributing 618,837 person-years of follow-up. Median CD4+T-cell count was 109 cells/mm3and median age 37 years. The overall life expectancy after cART initiation at age 20 was 25.4 (95% CI, 25.3, 25.6) years and 20.6 (95% CI, 20.5, 20.7) at age 35 years. Life expectancy at baseline CD4+T-cell count =350 cells/mm3was 51.9 (95% CI, 51.0, 52.9) years for age 20 years and 43.2 (95% CI, 42.4, 44.1) years for age 35 years, close to life expectancy in the general Thai population.Conclusions Increasing life expectancy with higher baseline CD4+T-cell counts supports the guideline recommendations to start cART irrespective of CD4+T-cell count. These results are beneficial to forecast the treatment cost and develop health policies for people living with HIV in Thailand and Asia.

Background Antiretroviral treatment (ART) for HIV-positive patients has expanded rapidly in Asia over the last 10 years. Our study aimed to describe the time trends and risk factors for overall survival in patients receiving first-line ART in Asia.Methods We included HIV-positive adult patients who initiated ART between 2003–2013 (n=16,546), from seven sites across six Asia–Pacific countries. Patient follow-up was to May 2014. We compared survival for each country and overall by time period of ART initiation using Kaplan–Meier curves. Factors associated with mortality were assessed using Cox regression, stratified by site. We also summarized first-line ART regimens, CD4+T-cell count at ART initiation, and CD4+T-cell and HIV viral load testing frequencies.Results There were 880 deaths observed over 54,532 person-years of follow-up, a crude rate of 1.61 (95% CI 1.51, 1.72) per 100 person-years. Survival significantly improved in more recent years of ART initiation. The survival probability at 4 years follow-up for those initiating ART in 2003–2005 was 92.1%, 2006–2009 was 94.3% and 2010–2013 was 94.5% (P=0.001). Factors associated with higher mortality risk included initiating ART in earlier time periods, older age, male sex, injecting drug use as HIV exposure and lower pre-ART CD4+T-cell count. Concurrent with improved survival was increased tenofovir use, ART initiation at higher CD4+T-cell counts and greater monitoring of CD4+T-cells and HIV viral load.Conclusions Our results suggest that HIV-positive patients from Asia have improved survival in more recent years of ART initiation. This is likely a consequence of improvements in treatment, patient management and monitoring over time.

Background Antiretroviral (ART) drugs have been associated with higher triglycerides (TG), higher total cholesterol (TC) and lower high-density lipoprotein cholesterol (HDL-C) levels. Associations between lipid levels with HIV viraemia and immunosuppression in the presence of ART remain unclear.Methods Participants from the D:A:D study with at least one TG/TC/HDL-C measurement were included. Linear mixed effect models were used to determine the association of ART, viral load (VL), nadir and current CD4+T-cell count and previous AIDS diagnosis with lipids.Results Of 49,717 participants, 90%, 92% and 80% contributed at least one TG/TC/HDL-C measurement (median follow-up 6.8, 6.8 and 5.0 years, respectively). Predicted mean (95% CI) baseline levels for TG, TC and HDL-C (mmol/l), were 2.10 (2.05, 2.14), 4.94 (4.91, 4.98) and 1.08 (1.07, 1.10), respectively. Lopinavir was associated with the worst TG profile, (27.2% higher levels compared to atazanavir; 95% CI 25.2%, 29.2%), and darunavir had a similar profile as atazanavir. The nucleoside pair lamivudine/tenofovir was associated with the most favourable TG profile (-2.8%; -3.5%, -2.0%) compared with emtricitabine/tenofovir, whereas lamivudine/abacavir (+10.2%; +9.3%, +11.2%) and lamivudine/ stavudine (+8.0%; +6.9%, +9.0%), were associated with the worst. Raltegravir was associated with lower TG (-5.2%; -6.4%, -3.9%), and nevirapine had a more favourable HDL-C profile (+11.3%; +10.8%, +11.7%) than efavirenz (+5.3%; 5.0%, 5.7%), compared to atazanavir. Higher VLs were associated with lower TG/TC/HDL-C, whereas higher CD4+T-cell counts were associated with higher TG/TC/HDL-C.Conclusions TG, TC and HDL-C levels, which generally improved over time, are dependent on ART, viraemia and, to a lesser extent, immunosuppression.

Background The World Health Organization recommends HBV–HIV-coinfected individuals start antiretroviral therapy containing tenofovir. Here we describe first-line tenofovir use and treatment outcomes in coinfected patients in Asia.Methods HBV surface antigen positive patients enrolled in the TREAT Asia HIV Observational Database who started first-line antiretroviral therapy were included. Logistic regression adjusted for period of treatment initiation was used to determine factors associated with tenofovir use. Generalized estimating equations were used to evaluate factors associated with alanine transaminase levels and CD4+T-cell count on treatment.Results There were 548 eligible patients, of whom 149 (27.2%) started tenofovir. Patients treated in high/high-middle income countries (odds ratio 4.4 versus low/low-middle, 95% CI 2.6, 7.4; P<0.001) and those with elevated baseline alanine transaminase (odds ratio 4.2 versus normal, 95% CI 2.4, 7.2; P<0.001) were more likely to receive tenofovir. Hepatitis C antibody positive patients (odds ratio 0.4 versus negative, 95% CI 0.2, 0.8; P=0.008) were less likely. In those starting antiretroviral therapy with elevated alanine transaminase, mean reduction after tenofovir initiation was 11.2 IU/l (95% CI 0.9, 21.6; P=0.034) lower compared with those using a non-tenofovir-based regimen although this did not significantly increase the chance of alanine transaminase normalization. Tenofovir use was not associated with a superior CD4+T-cell response.Conclusions HBV–HIV-coinfected patients in Asia are most likely to receive tenofovir if they are treated in a high/high-middle income country, have elevated alanine transaminase levels and are hepatitis C antibody negative. Compared to other antiretroviral therapies, tenofovir-based regimens more effectively reduce liver inflammation in HBV–HIV-coinfection but do not result in superior CD4+T-cell recovery.

Background Loss to follow-up (LTFU) in HIV-positive cohorts is an important surrogate for interrupted clinical care, which can potentially influence the assessment of HIV disease status and outcomes. After preliminary evaluation of LTFU rates and patient characteristics, we evaluated the risk of mortality by LTFU status in a high-resource setting.Methods Rates of LTFU were measured in the Australian HIV Observational Database for a range of patient characteristics. Multivariate repeated measures regression methods were used to identify determinants of LTFU. Mortality by LTFU status was ascertained using linkage to the National Death Index. Survival following combination antiretroviral therapy initiation was investigated using the Kaplan–Meier (KM) method and Cox proportional hazards models.Results Of 3,413 patients included in this analysis, 1,632 (47.8%) had at least one episode of LTFU after enrolment. Multivariate predictors of LTFU included viral load (VL)>10,000 copies/ml (rate ratio [RR] 1.63; 95% CI 1.45, 1.84; ref =400), time under follow-up (per year; RR 1.03; 95% CI 1.02, 1.04) and prior LTFU (per episode; RR 1.15; 95% CI 1.06, 1.24). KM curves for survival were similar by LTFU status (P=0.484). LTFU was not associated with mortality in Cox proportional hazards models (univariate hazard ratio [HR] 0.93; 95% CI 0.69, 1.26) and multivariate HR 1.04 (95% CI 0.77, 1.43).Conclusions Increased risk of LTFU was identified amongst patients with potentially higher infectiousness. We did not find significant mortality risk associated with LTFU. This is consistent with timely re-engagement with treatment, possibly via high levels of unreported linkage to other health-care providers.

Background There have been improvements in combination antiretroviral therapy (cART) over the past 15 years. The aim of this analysis was to assess whether improvements in ART have resulted in improvements in surrogates of HIV outcome.Methods Patients in the Australian HIV Observational Database who initiated treatment using mono/duo therapy prior to 1996, or using cART from 1996 onwards, were included in the analysis. Patients were stratified by era of ART initiation. Median changes in CD4+T-cell count and the proportion of patients with detectable HIV viral load (>400 copies/ml) were calculated over the first 4 years of treatment. Probabilities of treatment switch were estimated using the Kaplan-Meier method.Results A total of 2,753 patients were included in the analysis: 28% initiated treatment <1996 using mono/duo therapy and 72% initiated treatment =1996 using cART (30% 1996–1999, 12% 2000–2003, 11% 2004–2007 and 19% =2008). Overall CD4+T-cell count response improved by later era of initiation (P<0.001), although 2000–2003 CD4+T-cell count response was less than that for 1996– 1999 (P=0.007). The average proportion with detectable viral load from 2 to 4 years post-treatment commencement by era was: <1996 mono/duo 0.69 (0.67–0.71), 1996–1999 cART 0.29 (0.28–0.30), 2000–2003 cART 0.22 (0.20–0.24), 2004–2007 cART 0.09 (0.07–0.10) and =2008 cART 0.04 (0.03–0.05). Probability of treatment switch at 4 years after initiation decreased from 53% in 1996–1999 to 29% after 2008 (P<0.001).Conclusions Across the five time-periods examined, there have been incremental improvements for patients initiated on cART, as measured by overall response (viral load and CD4+T-cell count) and also increased durability of first-line ART regimens.

Background Biomarkers of inflammation, coagulation, lipids and vitamin D have been associated with cardiovascular and mortality risk in HIV-infected individuals. Scarce data exist on changes in these markers from pre-to post-HIV seroconversion.Methods The study participants were drawn from the Health in Men Study, which recruited HIV-negative homosexual men. Participants with incident HIV infection (n=26) were compared with HIV-negative controls (n=52) matched on age at enrolment, date of visit and reported intravenous drug use. Levels of metabolic (lipids and vitamin D), inflammatory (C-reactive protein and interleukin-6) and coagulation (D-dimer and fibrinogen) biomarkers were measured at pre- and post-HIV seroconversion visits and corresponding visits for controls. Random-effect models were used to compare changes in markers between cases and controls.Results The median gap between pre- and post-seroconversion or matched first and second visits in controls was 12 months. HIV seroconversion was associated with decline in high density lipoprotein (HDL-C; difference in mean change between cases and controls -0.14 mmol/l; 95% CI -0.22, -0.01; P=0.035). There were no significant differences in changes in other lipids, markers of inflammation, coagulation or vitamin D.Conclusions Decline in HDL-C seems to be the main proatherogenic change within 1–1.5 years after HIV seroconversion. HIV seroconversion was not associated with profound changes in other lipids, or markers of inflammation, coagulation and vitamin D. Longitudinal assessment of these markers in comparable population needs further assessment.

Objective To compare three versions of the objective HIV-associated lipodystrophy (HIVLD) case definition (LDCD) and derived severity scale to spontaneous clinical LD assessment in adults initiating antiretroviral therapy. Design and main outcome measures: The LDCD versions were the ‘primary’ LDCD [which includes dual-energy X-ray absorptiometry (DXA) and computerized tomography (CT)], a simpler ‘central’ LDCD that omits CT data, and a simpler but probably less accurate ‘non-imaging’ LDCD. Physician LD assessments were passively reported. Two of the 10 parameters in the primary LDCD were not collected and were imputed.Setting, participants and interventions Retrospective analysis of a randomized, placebo-controlled, 144-week study of tenofovir DF or stavudine (d4T) in 600 anti-retroviral-naive adults.Results Central LDCD and clinical assessment diagnosed LD in 27% and 19% of d4T recipients at week 144, respectively (P<0.001), and 3% and 3% of tenofovir DF recipients, respectively (P=0.248). The central LDCD performed at least as well as the primary LDCD; both were more sensitive than the non-imaging model. There was poor concordance between clinical and LDCD-based diagnosis (kappa 0.02–0.20); most clinical cases did not fulfill any LDCD. Using the central LDCD, most LD was grade 1; 6% of d4T recipients and no tenofovir DF recipient had grade 3–4 LD at week 144 (P=0.007). Independent risk factors for LD using the central LDCD were d4T, increasing age, female sex and higher baseline triglycerides, whereas clinical assessment consistently identified only d4T. The LDCD score was more sensitive than DXA for assessing LD severity.Conclusions In this prospective study of a first antiretroviral regimen, the LDCD was more sensitive for LD diagnosis and identified more lipodystrophy risk factors than spontaneous clinical assessment or DXA, and also objectively quantified LD severity. The central LDCD should make objective LD assessment cheaper and simpler. Spontaneous clinical LD assessment of is of limited value, even in placebo-controlled trials.

Objective We assessed predictors of changes in systolic (SBP) and diastolic (DBP) blood pressure during follow-up and of the development of hypertension in HIV-infected individuals.Methods International cohort collaborative study (D:A:D) of established prospective cohorts of HIV-1-infected patients. Longitudinal analysis of changes in blood pressure (BP) was performed using mixed effects models in 17170 patients. Predictors of development of hypertension during follow-up (systolic BP =140 and/or diastolic BP =90 mmHg or initiation of antihypertensive treatment) were assessed using Cox models in 8 984 patients with a normal BP level at baseline.Results 73548 BP measurements with a median of 4 per patient (interquartile range [IQR]: 2–6) were recorded over a median follow-up of 2.3 years (IQR: 1.5–2.6). Risk factors significantly associated with a development of higher systolic BP and diastolic BP (differences =5 mmHg and P-values <0.001) during follow-up were: older age, male sex, higher body mass index (BMI) and use of BP-lowering drugs. In patients with normal BP at baseline, 1186 developed hypertension for an incidence of 72.1 per 1000 person-years (95% confidence interval: 68.2–76.0). Factors associated with development of hypertension were: male sex, higher BMI, older age, higher BP at baseline, high total cholesterol and clinical lipodystrophy. Cumulative duration of exposure to nucleoside reverse transcriptase inhibitors (P=0.75), protease inhibitors (P=0.92) as well as type of antiretroviral treatment at baseline (P=0.18) were not associated with a higher risk of hypertension. Cumulative duration of exposure to non-nucleoside reverse transcriptase inhibitors (NNRTIs) was significantly associated with lower risk of hypertension (hazard ratio=0.78 and 0.67 for those treated =10 months and >10 months compared with no exposure; P=0.005).Conclusions Increased blood pressure in HIV-infected individuals is associated with established risk factors for hypertension. There was no evidence for an independent deleterious effect of any class of antiretroviral drugs on BP, although the use of NNRTIs was associated with a lower risk of development of hypertension.

An understanding of the natural history of hepatitis C virus (HCV) infection has improved in recent years. Estimates of liver disease progression among people with chronic hepatitis C have been developed from various study populations, including liver clinics, post-transfusion hepatitis C cohorts and community-based cohorts. These estimates can be used in hepatitis C natural history models; however, they need to be matched to differing requirements. Estimation and projection of liver disease burden at the population level requires estimates of HCV prevalence and incidence, and disease progression among all people with chronic hepatitis C. Liver disease progression based on community cohorts would appear the most appropriate for a population level model. In contrast, models that examine the cost-effectiveness of antiviral therapy for people with chronic hepatitis C require disease progression estimates from the treatment setting. Further models are required to determine individual prognosis and should be based on an assessment of cofactors for liver disease progression.

Objective A case definition of HIV lipodystrophy has recently been developed from a combination of clinical, metabolic and imaging/body composition variables using logistic regression methods. We aimed to evaluate whether artificial neural networks could improve the diagnostic accuracy.Methods The database of the case-control Lipodystrophy Case Definition Study was split into 504 subjects (265 with and 239 without lipodystrophy) used for training and 284 independent subjects (152 with and 132 without lipodystrophy) used for validation. Back-propagation neural networks with one or two middle layers were trained and validated. Results were compared against logistic regression models using the same information.Results Neural networks using clinical variables only (41 items) achieved consistently superior performance than logistic regression in terms of specificity, overall accuracy and area under the ROC curve. Their average sensitivity and specificity were 72.4 and 71.2%, as compared with 73.0 and 62.9% for logistic regression, respectively (area under the ROC curve, 0.784 vs 0.748). The discriminating performance of the neural networks was largely unaffected when built excluding 13 parameters that patients may not have readily available. The average sensitivity and specificity of the neural networks remained the same when metabolic variables were also considered (total 60 items) without a clear advantage against logistic regression (overall accuracy 71.8%). The performance of networks considering also body composition variables was similar to that of logistic regression (overall accuracy 78.5% for both).Conclusions Neural networks may offer a means to improve the discriminating performance for HIV lipodystrophy, when only clinical data are available and a rapid approximate diagnostic decision is needed. In this context, information on metabolic parameters is apparently not helpful in improving the diagnosis of HIV lipodystrophy, unless imaging and body composition studies are also obtained.

Objectives To compare two analytic approaches to assess the virological effect of HAART according to the intention-to-treat (ITT) principle.Material Data from 2318 patients enrolled in 10 randomised clinical trials (RCTs) and from 3091 patients followed in an observation cohort (EuroSIDA) starting their first HAART regimen.Methods Two classifications of defining virological response 48 weeks after starting the therapy to be evaluated were compared: 1) only patients remaining on the therapy and having a plasma viral load (pVL) below a given cut-off level at week 48 were classified as responders (ITT/s=f); and 2) patients with a pVL below a given cut-off at week 48 whether they remained on initial assigned therapy or switched therapy were responders (ITT/s incl). In both analyses, patients with missing data at week 48 were classified as failures (i.e., non-responders).Results According to ITT/s=f, 22–70% of the patients starting a HAART regimen in a RCT experienced a virological response at week 48. Only two RCTs had complete follow-up data (n=424): between 29 and 62% achieved a virological response at week 48 in the six treatment arms evaluated in the studies according to ITT/s=f, and 41–72% according to ITT/s incl. Among those who discontinued the therapy to be evaluated in these two trials, 13–45% (cohort: 39–74%) subsequently experienced a virological response at week 48. The subsequent response rates were associated with the reason for discontinuation (toxicity versus confirmed virological failure: 63 vs 33%), varied largely across regimens and were not associated with the discontinuation rate.Conclusions Discontinuation of follow-up at switch from the therapy to be evaluated remains common in anti-retroviral treatment trials, but leads to an imprecise and incomplete assessment of the intrinsic effect of a given regimen. Complete follow-up of all patients should be encouraged strongly as this will allow for several complementary analytic approaches and a focus on optimal treatment strategies rather than specific regimens.