Triple-class virologic failure in HIV-infected patients undergoing antiretroviral therapy for up to 10 years

Heavy antiretroviral exposure and exhausted/limited antiretroviral options: predictors and clinical outcomes

OBJECTIVES

People with HIV and extensive antiretroviral exposure may have limited/exhausted treatment options (LExTO) due to resistance, comorbidities, or antiretroviral-related toxicity. Predictors of LExTO were investigated in the RESPOND cohort.

METHODS

Participants on ART for at least 5 years were defined as having LExTO when switched to at least two anchor agents and one third antiretroviral (any class), a two-drug regimen of two anchor agents (excluding rilpivirine with dolutegravir/cabotegravir), or at least three nucleoside reverse transcriptase inhibitors. Baseline was the latest of January 1, 2012, cohort enrolment or 5 years after starting antiretrovirals. Poisson regression modeled LExTO rates and clinical events (all-cause mortality, non-AIDS malignancy, cardiovascular disease [CVD], and chronic kidney disease [CKD]).

RESULTS

Of 23 827 participants, 2164 progressed to LExTO (9.1%) during 130 061 person-years follow-up (PYFU); incidence 1.66/100 PYFU (95% CI 1.59-1.73). Predictors of LExTO were HIV duration more than 15 years (vs. 7.5-15; adjusted incidence rate ratio [aIRR] 1.32; 95% CI 1.19-1.46), development of CKD (1.84; 1.59-2.13), CVD (1.64; 1.38-1.94), AIDS (1.18; 1.07-1.30), and current CD4 + cell count of 350 cells/μl or less (vs. 351-500 cells/μl, 1.51; 1.32-1.74). Those followed between 2018 and 2021 had lower rates of LExTO (vs. 2015-2017; 0.52; 0.47-0.59), as did those with baseline viral load of 200 cp/ml or less (0.46; 0.40-0.53) and individuals under 40. Development of LExTO was not significantly associated with clinical events after adjustment for age and current CD4, except CKD (1.74; 1.48-2.05).

CONCLUSION

Despite an aging and increasingly comorbid population, we found declining LExTO rates by 2018-2021, reflecting recent developments in contemporary ART options and clinical management. Reassuringly, LExTO was not associated with a significantly increased incidence of serious clinical events apart from CKD.

Inflammation burden score in multidrug-resistant HIV-1 infection

OBJECTIVES

Four-class drug-resistant (4DR) people living with HIV (PLWH) are a fragile population with a high burden of disease. No data on their inflammation and T-cell exhaustion markers are currently available.

METHODS

Inflammation, immune activation and microbial translocation biomarkers were measured through ELISA in 30 4DR-PLWH with HIV-1 RNA ≥ 50 copies/mL, 30 non-viremic 4DR-PLWH and 20 non-viremic non-4DR-PLWH. Groups were matched by age, gender and smoking habit. T-cell activation and exhaustion markers were assessed by flow cytometry in 4DR-PLWH. An inflammation burden score (IBS) was calculated from soluble marker levels and associated factors were estimated through multivariate regression.

RESULTS

The highest plasma biomarker concentrations were observed in viremic 4DR-PLWH, the lowest ones in non-4DR-PLWH. Endotoxin core immunoglobulin G showed an opposite trend. Among 4DR-PLWH, CD38/HLA-DR and PD-1 were more expressed on CD4+ (p = 0.019 and 0.034, respectively) and CD8+ (p = 0.002 and 0.032, respectively) cells of viremic compared to non-viremic subjects. An increased IBS was significantly associated with 4DR condition, higher values of viral load and a previous cancer diagnosis.

CONCLUSIONS

Multidrug-resistant HIV infection is associated with a higher IBS, even when viremia is undetectable. Therapeutic approaches aimed to reduce inflammation and T-cell exhaustion in 4DR-PLWH need to be investigated.

Pharmacokinetics of Temsavir, the Active Moiety of the HIV-1 Attachment Inhibitor Prodrug, Fostemsavir, Coadministered with Cobicistat, Etravirine, Darunavir/Cobicistat, or Darunavir/Ritonavir with or without Etravirine in Healthy Participants

Fostemsavir is a prodrug of temsavir, a first-in-class attachment inhibitor that binds directly to HIV-1 gp120, preventing initial viral attachment and entry into host CD4⁺ T cells with demonstrated efficacy in phase 2 and 3. Temsavir is a P-glycoprotein and breast cancer resistance protein (BCRP) substrate; its metabolism is mediated by esterase and CYP3A4 enzymes. Drugs that induce or inhibit CYP3A, P-glycoprotein, and BCRP may affect temsavir concentrations. Understanding potential drug-drug interactions (DDIs) following fostemsavir coadministration with antiretrovirals approved for HIV-1-infected treatment-experienced patients, including darunavir plus cobicistat (DRV/c) or DRV plus low-dose ritonavir (DRV/r) and etravirine, is clinically relevant. Open-label, single-sequence, multiple-dose, multicohort DDI studies were conducted in healthy participants (n = 46; n = 32). The primary objective was to assess the effects of DRV/r, etravirine, DRV/r plus etravirine, cobicistat, and DRV/c on temsavir systemic exposures; safety was a secondary objective. Compared with fostemsavir alone, coadministration with DRV/r increased the temsavir maximum observed plasma concentration (C_max), area under the concentration-time curve in one dosing interval (AUC_tau), and plasma trough concentration (C_tau) by 52%, 63%, and 88%, respectively, while etravirine decreased the temsavir C_max, AUC_tau, and C_tau by ∼50% each. DRV/r plus etravirine increased the temsavir C_max, AUC_tau, and C_tau by 53%, 34%, and 33%, respectively. Compared with fostemsavir alone, coadministration with cobicistat increased the temsavir C_max, AUC_tau, and C_tau by 71%, 93%, and 136%, respectively; DRV/c increased the temsavir C_max, AUC_tau, and C_tau by 79%, 97%, and 124%, respectively. Fostemsavir with all combinations was generally well tolerated. No dose adjustment is required for fostemsavir when coadministered with strong CYP3A inhibitors, P-glycoprotein inhibitors, and modest inducers, including regimens with DRV/r, DRV/c, cobicistat, etravirine, and DRV/r plus etravirine based on the therapeutic margin for temsavir (ClinicalTrials.gov registration no. NCT02063360 and NCT02277600).

Drug Resistance in HIV-Positive Adults During the Initial Year of Antiretroviral Treatment at Ethiopian Health Centers

Background

The increasing prevalence of antiretroviral drug resistance in Sub-Saharan Africa threatens the success of HIV programs. We have characterized patterns of drug resistance mutations (DRMs) during the initial year of antiretroviral treatment (ART) in HIV-positive adults receiving care at Ethiopian health centers and investigated the impact of tuberculosis on DRM acquisition.

Methods

Participants were identified from a cohort of ART-naïve individuals aged ≥18 years, all of whom had been investigated for active tuberculosis at inclusion. Individuals with viral load (VL) data at 6 and/or 12 months after ART initiation were selected for this study. Genotypic testing was performed on samples with VLs ≥500 copies/mL obtained on these occasions and on pre-ART samples from those with detectable DRMs during ART. Logistic regression analysis was used to investigate the association between DRM acquisition and tuberculosis.

Results

Among 621 included individuals (110 [17.5%] with concomitant tuberculosis), 101/621 (16.3%) had a VL ≥500 copies/mL at 6 and/or 12 months. DRMs were detected in 64/98 cases with successful genotyping (65.3%). DRMs were detected in 7/56 (12.5%) pre-ART samples from these individuals. High pre-ART VL and low mid-upper arm circumference were associated with increased risk of DRM acquisition, whereas no such association was found for concomitant tuberculosis.

Conclusions

Among adults receiving health center–based ART in Ethiopia, most patients without virological suppression during the first year of ART had detectable DRM. Acquisition of DRM during this period was the dominant cause of antiretroviral drug resistance in this setting. Tuberculosis did not increase the risk of DRM acquisition.

Substantial decline in heavily treated therapy-experienced persons with HIV with limited antiretroviral treatment options

OBJECTIVE

Historically, a high burden of resistance to antiretroviral therapy (ART) in heavily treatment-experienced (HTE) persons with HIV (PWH) resulted in limited treatment options (LTOs). We evaluated the prevalence, risk factors, and virologic control of HTE PWH with LTO throughout the modern ART era.

DESIGN

We examined all ART-experienced PWH in care between 2000 and 2017 in the Centers for AIDS Research Network of Integrated Clinical Systems cohort.

METHODS

We computed the annual prevalence of HTE PWH with LTO defined as having two or less available classes with two or less active drugs per class based on genotypic data and cumulative antiretroviral resistance. We used multivariable Cox proportional hazards models to examine risk of LTO by 3-year study entry periods adjusting for demographic and clinical characteristics.

RESULTS

Among 27 133 ART-experienced PWH, 916 were classified as having LTO. The prevalence of PWH with LTO was 5.2-7.5% in 2000-2006, decreased to 1.8% in 2007, and remained less than 1% after 2012. Persons entering the study in 2009-2011 had an 80% lower risk of LTO compared with those entering in 2006-2008 (adjusted hazard ratio 0.20; 95% confidence interval: 0.09-0.42). We found a significant increase in undetectable HIV viral loads among PWH ever classified as having LTO from less than 30% in 2001 to more than 80% in 2011, comparable with persons who never had LTO.

CONCLUSION

Results of this large multicenter study show a dramatic decline in the prevalence of PWH with LTO to less than 1% with the availability of more potent drugs and a marked increase in virologic suppression in the current ART era.

New antiretroviral agent use affects prevalence of HIV drug resistance in clinical care populations

OBJECTIVE

To estimate the prevalence of HIV drug resistance over time and identify risk factors for multiclass resistance.

DESIGN

Prospective clinical cohort of HIV-infected patients at the University of North Carolina.

METHODS

Among antiretroviral therapy (ART)-experienced patients in care 2000-2016, we estimated annual prevalences of cumulative resistance, defined as at least one major mutation by drug class. Clinical data and multiple imputation were used when genotypic data were missing, and mutations were carried forward in time. We estimated resistance odds ratios comparing characteristics of patients in care in 2016.

RESULTS

A total of 3682 patients contributed 23 169 person-years. Prevalence of at least one major resistance mutation, irrespective of viral suppression, peaked in 2005 with 49% (95% confidence interval 46, 52) and decreased to 38% (35, 40) in 2016. Resistance to nucleoside reverse transcriptase inhibitors, protease inhibitors, and nonnucleoside reverse transcriptase inhibitors also peaked in 2005-2007 and decreased to 28 (26, 31), 14 (12, 16), and 27% (24, 29) in 2016, respectively. In 2016, prevalence of integrase strand transfer inhibitor (INSTI) resistance was 2% (1, 3) and triple-class resistance 10% (9, 12). Over the study period, cumulative resistance was frequent among patients with detectable viremia, but uncommon among patients initiating ART post-2007. Among 1553 patients in care in 2016, ART initiation at an older age, with an INSTI, and with higher CD4 cell counts were associated with resistance to fewer or no classes.

CONCLUSION

Prevalence of resistance to older ART classes has decreased in the last 10 years in this clinical cohort, whereas INSTI resistance has increased but remained very low. Patients with viremia continue to have a high burden of resistance even if they initiated ART recently.

Impact of etravirine on hospitalization rate between 2005 and 2011 among heavily treated HIV-1-infected individuals on failing regimens

Background

Etravirine (ETR), a non-nucleoside reverse transcriptase inhibitor (NNRTI) available in France since 2006, is indicated for antiretroviral-experienced HIV-infected adults, in combination with a ritonavir-boosted protease inhibitor (PI). To assess its clinical impact in routine care, we compared hospitalization rates according to ETR + PI prescription or not, among heavily treated HIV-1 infected individuals on failing regimens between 2005 and 2011.

Methods

From the French Hospital Database on HIV (ANRS CO4), we selected heavily treated individuals (prior exposure to at least 2 nucleoside reverse transcriptase inhibitor (NRTI), 2PI and 1 NNRTI) with viral load (VL) > 50 copies/mL who started a new antiretroviral (ARV) regimen between 2005 and 2011. Using an intention-to-continue-treatment approach, hospitalization rates were calculated for the individuals who received ETR + PI, during the months after initiating ETR + PI (ETR + PI) or for the individuals who received ETR + PI, in the months before ETR + PI initiation and for the individuals who never received ETR + PI (no ETR + PI). hospitalization from an AIDS-defining cause and hospitalization from a non-AIDS defining cause rates were also calculated. Poisson regression models were used to compare the incidences between the two groups, with adjustment for potential confounders.

Results

Of 3884 patients who met the inclusion criteria, 838 (21.6%) received ETR + PI. During 13,986 person-years (P-Y) of follow-up, there were 2484 hospitalizations in 956 individuals. The hospitalization rates per 1000 P-Y were 169.0 among individuals exposed to ETR + PI and 179.3 among those not exposed to ETR + PI. After adjustment, the respective hospitalization rates were 148.8 and 186.7 per 1000 P-Y, with an estimated relative risk of 0.80 (95%CI: 0.71–0.90), AIDS hospitalization rates were 11.5 and 22.7 per 1000 P-Y, with an estimated relative risk of 0.51(95%CI: 0.39–0.66) and non-AIDS hospitalization rates were 139.5 and 152.2 per 1000 P-Y, with an estimated relative risk of 0.92 (95%CI: 0.80–1.05).

Conclusions

Between 2005 and 2011, access to ETR + PI was associated with a 20% reduction in the hospitalization rate among heavily treated HIV-1-infected individuals. This reduction was mainly due to a reduction in the AIDS hospitalization rate.

Long-term clinical, immunological and virological outcomes of patients on antiretroviral therapy in southern Myanmar

Objective

To study the long-term clinical, immunological and virological outcomes among people living with HIV on antiretroviral therapy (ART) in Myanmar.

Methods

A retrospective analysis of people on ART for >9 years followed by a cross-sectional survey among the patients in this group who remained on ART at the time of the survey. Routinely collected medical data established the baseline clinical and demographic characteristics for adult patients initiating ART between 2004 and 2006. Patients remaining on ART between March-August 2015 were invited to participate in a survey assessing clinical, virological, immunological, and biochemical characteristics.

Results

Of 615 patients included in the retrospective analysis, 35 (6%) were lost-to-follow-up, 9 (1%) were transferred, 153 died (25%) and 418 (68%) remained active in care. Among deaths, 48 (31.4%) occurred within 3 months of ART initiation, and 81 (52.9%) within 12 months, 90.1% (n = 73) of which were initially classified as stage 3/4. Of 385 patients included in the survey, 30 (7.7%) were on second-line ART regimen; 373 (96.8%) had suppressed viral load (<250 copies/ml). The mean CD4 count was 548 cells/ mm3 (SD 234.1) after ≥9 years on treatment regardless of the CD4 group at initiation. Tuberculosis while on ART was diagnosed in 187 (48.5%); 29 (7.6%) had evidence of hepatitis B and 53 (13.9%) of hepatitis C infection.

Conclusions

Appropriate immunological and virological outcomes were seen among patients on ART for ≥9 years. However, for the complete initiating cohort, high mortality was observed, especially in the first year on ART. Concerning co-infections, tuberculosis and viral hepatitis were common among this population. Our results demonstrate that good long-term outcomes are possible even for patients with advanced AIDS at ART initiation.

M, Diana B, Monique T, Christine S, Rikke SB, Nina FM, Dorthe R, David H, Matthias E, Ian W, Stéphane DW. Cohort Profile: Collaboration of Observational HIV Epidemiological Research Europe (COHERE) in EuroCoord

Many questions about the long-term effects of combination antiretroviral therapy (cART) on clinical outcomes in people living with HIV (PLWH) and their impact on health systems remain unanswered. The Collaboration of Observational HIV Epidemiological Research Europe (COHERE) was formed in 2005 to pool and harmonize existing longitudinal data on people living with HIV in Europe, to answer key research questions that could not be addressed adequately by individual cohorts. Key research questions include long-term prognosis, rare outcomes, and variations across patient groups, settings and health systems. COHERE uses the HIV Cohorts Data Exchange Protocol, a standardized and validated method of data structure and transfer, to compile data from over 40 cohorts of PLWH residing in Europe, representing 331 481 individuals, including 2808 children (<13), representing 2 135 896 person-years of follow-up. COHERE compiles data on clinical characteristics, antiretroviral therapy and other medications, HIV seroconversion, opportunistic infections, laboratory results and socio demographic data. External collaborators interested in conducting a project in COHERE should submit a project proposal to the Regional Coordinating Centres in Bordeaux and Copenhagen for review by COHERE’s governing bodies (see www.cohere.org for further information).

Higher rates of triple-class virological failure in perinatally HIV-infected teenagers compared with heterosexually infected young adults in Europe

OBJECTIVES

The aim of the study was to determine the time to, and risk factors for, triple-class virological failure (TCVF) across age groups for children and adolescents with perinatally acquired HIV infection and older adolescents and adults with heterosexually acquired HIV infection.

METHODS

We analysed individual patient data from cohorts in the Collaboration of Observational HIV Epidemiological Research Europe (COHERE). A total of 5972 participants starting antiretroviral therapy (ART) from 1998, aged < 20 years at the start of ART for those with perinatal infection and 15-29 years for those with heterosexual infection, with ART containing at least two nucleoside reverse transcriptase inhibitors (NRTIs) and a nonnucleoside reverse transcriptase inhibitor (NNRTI) or a boosted protease inhibitor (bPI), were followed from ART initiation until the most recent viral load (VL) measurement. Virological failure of a drug was defined as VL > 500 HIV-1 RNA copies/mL despite ≥ 4 months of use. TCVF was defined as cumulative failure of two NRTIs, an NNRTI and a bPI.

RESULTS

The median number of weeks between diagnosis and the start of ART was higher in participants with perinatal HIV infection compared with participants with heterosexually acquired HIV infection overall [17 (interquartile range (IQR) 4-111) vs. 8 (IQR 2-38) weeks, respectively], and highest in perinatally infected participants aged 10-14 years [49 (IQR 9-267) weeks]. The cumulative proportion with TCVF 5 years after starting ART was 9.6% [95% confidence interval (CI) 7.0-12.3%] in participants with perinatally acquired infection and 4.7% (95% CI 3.9-5.5%) in participants with heterosexually acquired infection, and highest in perinatally infected participants aged 10-14 years when starting ART (27.7%; 95% CI 13.2-42.1%). Across all participants, significant predictors of TCVF were those with perinatal HIV aged 10-14 years, African origin, pre-ART AIDS, NNRTI-based initial regimens, higher pre-ART viral load and lower pre-ART CD4.

CONCLUSIONS

The results suggest a beneficial effect of starting ART before adolescence, and starting young people on boosted PIs, to maximize treatment response during this transitional stage of development.

Associations between HIV-RNA-based indicators and virological and clinical outcomes

OBJECTIVES

To evaluate and compare the performance of six HIV-RNA-based quality of care indicators for predicting short-term and long-term outcomes.

DESIGN

Multinational cohort study.

METHODS

We included EuroSIDA patients on antiretroviral therapy (ART) with at least three viral load measurements after baseline (the latest of 01/01/2001 or entry into EuroSIDA). Using multivariate Poisson regression, we modelled the association between short-term (resistance, triple-class failure) and long-term (all-cause mortality, any AIDS/non-AIDS clinical event) outcomes and the indicators: viraemia copy years; consecutive months with viral load ≥ 50 copies/ml; percentage of time on ART spent fully suppressed (%FS); stable on ART; 48 weeks snapshot; and current viral load. Indicators were compared using area under the ROC curve (AUC) and different measures of model fit.

RESULTS

Adjusted incidence rate ratios for all outcomes tended to increase with increasing viraemia copy years, number of consecutive months with viral load ≥ 50 copies/ml, current viral load and with lower %FS, but the gradient of increased risk was weak across strata. None of the indicators reliably identified those at risk of long-term outcomes (AUC 0.54-0.58), but performed consistently better with short-term outcomes [triple class failure (AUC 0.67-0.76) and resistance (AUC 0.64-0.79)]. Goodness of fit varied with the outcome evaluated, but differences between indicators were small.

CONCLUSION

Differences between quality of care indicators were small and no indicator performed consistently better than current viral load. Given the simplicity in assessing and interpreting this indicator, we propose to use current viral load when HIV-RNA-based indicators are used to evaluate the efficacy of ART programs.

Long-term virological outcome in children on antiretroviral therapy in the UK and Ireland

Objective:

To assess factors at the start of antiretroviral therapy (ART) associated with long-term virological response in children.

Design:

Multicentre national cohort.

Methods:

Factors associated with viral load below 400 copies/ml by 12 months and virologic failure among children starting 3/4-drug ART in the UK/Irish Collaborative HIV Paediatric Study were assessed using Poisson models.

Results:

Nine hundred and ninety-seven children started ART at a median age of 7.7 years (inter-quartile range 2.9–11.7), 251 (25%) below 3 years: 411 (41%) with efavirenz and two nucleoside reverse transcriptase inhibitors (EFV + 2NRTIs), 264 (26%) with nevirapine and two NRTIs (NVP + 2NRTIs), 119 (12%; 106 NVP, 13 EFV) with non-nucleoside reverse transcriptase inhibitor and three NRTIs (NNRTI + 3NRTIs), and 203 (20%) with boosted protease inhibitor-based regimens. Median follow-up after ART initiation was 5.7 (3.0–8.8) years. Viral load was less than 400 copies/ml by 12 months in 92% [95% confidence interval (CI) 91–94%] of the children. Time to suppression was similar across regimens (P = 0.10), but faster over calendar time, with older age and lower baseline viral load. Three hundred and thirty-nine (34%) children experienced virological failure. Although progression to failure varied by regimen (P < 0.001) and was fastest for NVP + 2NRTIs regimens, risk after 2 years on therapy was similar for EFV + 2NRTIs and NVP + 2NRTIs, and lowest for NNRTI + 3NRTIs regimens (P-interaction = 0.03). Older age, earlier calendar periods and maternal ART exposure were associated with increased failure risk. Early treatment discontinuation for toxicity occurred more frequently for NVP-based regimens, but 5-year cumulative incidence was similar: 6.1% (95% CI 3.9–8.9%) NVP, 8.3% (95% CI 5.6–11.6) EFV, and 9.8% (95% CI 5.7–15.3%) protease inhibitor-based regimens (P = 0.48).

Conclusion:

Viral load suppression by 12 months was high with all regimens. NVP + 3NRTIs regimens were particularly efficacious in the longer term and may be a good alternative to protease inhibitor-based ART in young children.

The successful application of a national peer advisory committee for physicians who provide salvage regimens to heavily antiretroviral-experienced patients in mexican human immunodeficiency virus clinics

BACKGROUND

Designing optimal antiretroviral (ARV) salvage regimens for multiclass drug-resistant, human immunodeficiency virus (HIV)-infected patients demands specific clinical skills. Our aim was to assess the virologic and immunologic effects of the treatment recommendations drafted by a peer advisory board to physicians caring for heavily ARV-experienced patients.

METHODS

We conducted a nationwide, HIV clinic-based, cohort study in Mexico. Adults infected with HIV were assessed for a median of 33 months (interquartile range [IQR] = 22-43 months). These patients had experienced the virologic failure of at least 2 prior ARV regimens and had detectable viremia while currently being treated; their physicians had received therapeutic advice, by a panel of experts, regarding the ARV salvage regimen. The primary endpoint was the incidence of loss of virologic response (plasma HIV-RNA levels of <200 copies per mL, followed by levels above this threshold) during the follow-up assessment using an observed-failure competing risks regression analysis.

RESULTS

A total of 611 patients were observed (median ARV therapy exposure = 10.5 years; median prior regimens = 4). The probabilities of virologic failure were 11.9%, 14.4%, 16.9%, and 19.4% at the 12-, 24-, 36-, and 48-month follow-up assessments, respectively. Of the 531 patients who achieved a confirmed plasma HIV-RNA level below 200 copies per mL, the median increase in blood CD4(+) T-cell count was 162 cells per mL (IQR = 45-304 cells per mL).

CONCLUSIONS

In routine practice, a high rate of patients with extensive ARV experience, who received an optimized salvage regimen recommended by a peer advisory committee, achieved a long-term sustained virologic response and immune reconstitution.

Antiretroviral therapy: treatment-experienced individuals

Antiretroviral therapy (ART)-experienced individuals may choose to modify their regimens because of suboptimal virologic response, poor tolerability, convenience, or to minimize interactions with other medications or food. Constructing a new regimen for any of these reasons requires a thorough review of prior antiretroviral drug use and available drug resistance results. This article summarizes the strategies used in managing the ART-experienced individual who is considering a modification in therapy at the time of suboptimal virologic response or while virologically suppressed on a stable regimen.

Viral suppression following switch to second-line antiretroviral therapy: associations with nucleoside reverse transcriptase inhibitor resistance and subtherapeutic drug concentrations prior to switch

BACKGROUND

High rates of second-line antiretroviral treatment (ART) failure are reported. The association with resistance and nonadherence on switching to second-line ART requires clarification.

METHODS

Using prospectively collected data from patients in South Africa, we constructed a cohort of patients switched to second-line ART (1 January 2003 through 31 December 2008). Genotyping and drug concentrations (lamivudine, nevirapine, and efavirenz) were measured on stored samples preswitch. Their association with viral load (VL) <400 copies/mL by 15 months was assessed using modified Poisson regression.

RESULTS

One hundred twenty-two of 417 patients (49% male; median age, 36 years) had genotyping (n = 115) and/or drug concentrations (n = 80) measured. Median CD4 count and VL at switch were 177 cells/µL (interquartile range [IQR], 77-263) and 4.3 log10 copies/mL (IQR, 3.8-4.7), respectively. Fifty-five percent (n = 44/80) had subtherapeutic drug concentrations preswitch. More patients with therapeutic vs subtherapeutic ART had resistance (n = 73): no major mutations (3% vs 51%), nonnucleoside reverse transcriptase inhibitor (94% vs 44%), M184V/I (94% vs 26%), and ≥ 1 thymidine analogue mutations (47% vs 18%), all P = .01; and nucleoside reverse transcriptase inhibitor (NRTI) cross-resistance mutations (26% vs 13%, P = .23). Following switch, 68% (n = 83/122) achieved VL <400 copies/mL. Absence of NRTI mutations and subtherapeutic ART preswitch were associated with failure to achieve VL <400 copies/mL.

CONCLUSIONS

Nonadherence, suggested by subtherapeutic ART with/without major resistance mutations, significantly contributed to failure when switching regimen. Unresolved nonadherence, not NRTI resistance, drives early second-line failure.

Predictors of CD4(+) T-cell counts of HIV type 1-infected persons after virologic failure of all 3 original antiretroviral drug classes

BACKGROUND

Low CD4(+) T-cell counts are the main factor leading to clinical progression in human immunodeficiency virus type 1 (HIV-1) infection. We aimed to investigate factors affecting CD4(+) T-cell counts after triple-class virological failure.

METHODS

We included individuals from the COHERE database who started antiretroviral therapy from 1998 onward and who experienced triple-class virological failure. CD4(+) T-cell counts obtained after triple-class virologic failure were analyzed using generalized estimating equations.

RESULTS

The analyses included 2424 individuals with a total of 23 922 CD4(+) T-cell count measurements. In adjusted models (excluding current viral load and year), CD4(+) T-cell counts were higher with regimens that included boosted protease inhibitors (increase, 22 cells/µL [95% confidence interval {CI}, 3.9-41]; P = .017) or drugs from the new classes (increase, 39 cells/µL [95% CI, 15-62]; P = .001), compared with nonnucleoside reverse-transcriptase inhibitor-based regimens. These associations disappeared when current viral load and/or calendar year were included. Compared with viral levels of <2.5 log(10) copies/mL, levels of 2.5-3.5, 3.5-4.5, 4.5-5.5, and >5.5 log(10) copies/mL were associated with CD4(+) T-cell count decreases of 51, 84, 137, and 186 cells/µL, respectively (P < .001).

CONCLUSIONS

The approximately linear inverse relationship between log(10) viral load and CD4(+) T-cell count indicates that there are likely immunologic benefits from lowering viral load even by modest amounts that do not lead to undetectable viral loads. This is important for patients with low CD4(+) T-cell counts and few drug options.

NNRTIs: future prospects

The contribution of efavirenz and nevirapine remains clinically relevant and is the reason for the frequent prescription of these two agents. Recent clinical data on efavirenz and nevirapine in naive patients confirms their effectiveness compared to protease inhibitors such as lopinavir/r (ACTG 5142) or atazanavir/r (ACTG 5202) for efavirenz, or such as atazanavir/r (ARTEN trial) for nevirapine. Their easy use is another advantage; efavirenz is part of the first triple therapy as a single tablet given once a day, and nevirapine, with its new extended-release formulation, was designed for a single daily intake. However, the two agents exhibit different safety profiles and pharmacological properties. Their penetration rates in the genital tracts are different (70 to 80% for nevirapine versus 0 to 3% for efavirenz in men and 13-80% for nevirapine versus 0 to 4% for efavirenz in women). Finally, the authors of two recent studies reported the differences in the residual VL measured by ultrasensitive assays in successfully treated patients. The VL of patients treated with nevirapine was significantly more frequently below the detection limit of 1 or 2.5 RNA copies/mL than patients treated with efavirenz.

Calendar time trends in the incidence and prevalence of triple-class virologic failure in antiretroviral drug-experienced people with HIV in Europe

BACKGROUND

Despite the increasing success of antiretroviral therapy (ART), virologic failure of the 3 original classes [triple-class virologic failure, (TCVF)] still develops in a small minority of patients who started therapy in the triple combination ART era. Trends in the incidence and prevalence of TCVF over calendar time have not been fully characterised in recent years.

METHODS

Calendar time trends in the incidence and prevalence of TCVF from 2000 to 2009 were assessed in patients who started ART from January 1, 1998, and were followed within the Collaboration of Observational HIV Epidemiological Research Europe (COHERE).

RESULTS

Of 91,764 patients followed for a median (interquartile range) of 4.1 (2.0-7.1) years, 2722 (3.0%) developed TCVF. The incidence of TCVF increased from 3.9 per 1000 person-years of follow-up [95% confidence interval (CI): 3.7 to 4.1] in 2000 to 8.8 per 1000 person-years of follow-up (95% CI: 8.5 to 9.0) in 2005, but then declined to 5.8 per 1000 person-years of follow-up (95% CI: 5.6 to 6.1) by 2009. The prevalence of TCVF was 0.3% (95% CI: 0.27% to 0.42%) at December 31, 2000, and then increased to 2.4% (95% CI: 2.24% to 2.50%) by the end of 2005. However, since 2005, TCVF prevalence seems to have stabilized and has remained below 3%.

CONCLUSIONS

The prevalence of TCVF in people who started ART after 1998 has stabilized since around 2005, which most likely results from the decline in incidence of TCVF from this date. The introduction of improved regimens and better overall HIV care is likely to have contributed to these trends. Despite this progress, calendar trends should continue to be monitored in the long term.

Neuropsychiatric complications of aging with HIV

Persons over age 50 are not only aging with human immunodeficiency virus (HIV) infection but also represent a high proportion of new HIV infections. Neuropsychiatric symptoms, including depression, cognitive impairment, and substance abuse, are very common in individuals infected with HIV. However, there is little understanding of the relationship between these HIV-related comorbid conditions in newly infected elderly patients compared to uninfected elderly and those who have survived after 20 years of HIV/AIDS. We summarize the current theories and research that link aging and HIV with psychiatric illnesses and identify emerging areas for improved research, treatment, and patient care.

Second-line antiretroviral therapy in a workplace and community-based treatment programme in South Africa: determinants of virological outcome

Background: As antiretroviral treatment (ART) programmes in resource-limited settings mature, more patients are experiencing virological failure. Without resistance testing, deciding who should switch to second-line ART can be difficult. The consequences for second-line outcomes are unclear. In a workplace- and community-based multi-site programme, with 6-monthly virological monitoring, we describe outcomes and predictors of viral suppression on second-line, protease inhibitor-based ART.

Methods: We used prospectively collected clinic data from patients commencing first-line ART between 1/1/03 and 31/12/08 to construct a study cohort of patients switched to second-line ART in the presence of a viral load (VL) ≥400 copies/ml. Predictors of VL<400 copies/ml within 15 months of switch were assessed using modified Poisson regression to estimate risk ratios.

Results: 205 workplace patients (91.7% male; median age 43 yrs) and 212 community patients (38.7% male; median age 36 yrs) switched regimens. At switch compared to community patients, workplace patients had a longer duration of viraemia, higher VL, lower CD4 count, and higher reported non-adherence on first-line ART. Non-adherence was the reported reason for switching in a higher proportion of workplace patients. Following switch, 48.3% (workplace) and 72.0% (community) achieved VL<400, with non-adherence (17.9% vs. 1.4%) and virological rebound (35.6% vs. 13.2% with available measures) reported more commonly in the workplace programme. In adjusted analysis of the workplace programme, lower switch VL and younger age were associated with VL<400. In the community programme, shorter duration of viraemia, higher CD4 count and transfers into programme on ART were associated with VL<400.

Conclusion: High levels of viral suppression on second-line ART can be, but are not always, achieved in multi-site treatment programmes with both individual- and programme-level factors influencing outcomes. Strategies to support both healthcare workers and patients during this switch period need to be evaluated; sub-optimal adherence, particularly in the workplace programme must be addressed.

CD4 cell count and the risk of AIDS or death in HIV-Infected adults on combination antiretroviral therapy with a suppressed viral load: a longitudinal cohort study from COHERE

BACKGROUND

Most adults infected with HIV achieve viral suppression within a year of starting combination antiretroviral therapy (cART). It is important to understand the risk of AIDS events or death for patients with a suppressed viral load.

METHODS AND FINDINGS

Using data from the Collaboration of Observational HIV Epidemiological Research Europe (2010 merger), we assessed the risk of a new AIDS-defining event or death in successfully treated patients. We accumulated episodes of viral suppression for each patient while on cART, each episode beginning with the second of two consecutive plasma viral load measurements <50 copies/µl and ending with either a measurement >500 copies/µl, the first of two consecutive measurements between 50-500 copies/µl, cART interruption or administrative censoring. We used stratified multivariate Cox models to estimate the association between time updated CD4 cell count and a new AIDS event or death or death alone. 75,336 patients contributed 104,265 suppression episodes and were suppressed while on cART for a median 2.7 years. The mortality rate was 4.8 per 1,000 years of viral suppression. A higher CD4 cell count was always associated with a reduced risk of a new AIDS event or death; with a hazard ratio per 100 cells/µl (95% CI) of: 0.35 (0.30-0.40) for counts <200 cells/µl, 0.81 (0.71-0.92) for counts 200 to <350 cells/µl, 0.74 (0.66-0.83) for counts 350 to <500 cells/µl, and 0.96 (0.92-0.99) for counts ≥500 cells/µl. A higher CD4 cell count became even more beneficial over time for patients with CD4 cell counts <200 cells/µl.

CONCLUSIONS

Despite the low mortality rate, the risk of a new AIDS event or death follows a CD4 cell count gradient in patients with viral suppression. A higher CD4 cell count was associated with the greatest benefit for patients with a CD4 cell count <200 cells/µl but still some slight benefit for those with a CD4 cell count ≥500 cells/µl.

Determinants of access to experimental antiretroviral drugs in an Italian cohort of patients with HIV: a multilevel analysis

Background

Identification of the determinants of access to investigational drugs is important to promote equity and scientific validity in clinical research. We aimed to analyze factors associated with the use of experimental antiretrovirals in Italy.

Methods

We studied participants in the Italian Cohort of Antiretroviral-Naive Patients (ICoNA). All patients 18 years or older who had started cART (≥ 3 drugs including at least two NRTI) after their enrolment and during 1997-2007 were included in this analysis. We performed a random effect logistic regression analysis to take into account clustering observations within clinical units. The outcome variable was the use of an experimental antiretroviral, defined as an antiretroviral started before commercial availability, in any episode of therapy initiation/change. Use of an experimental antiretroviral obtained through a clinical trial or an expanded access program (EAP) was also analyzed separately.

Results

A total of 9,441 episodes of therapy initiation/change were analyzed in 3,752 patients. 392 episodes (360 patients) involved an experimental antiretroviral. In multivariable analysis, factors associated with the overall use of experimental antiretrovirals were: number of experienced drugs (≥ 8 drugs versus "naive": adjusted odds ratio [AOR] = 3.71) or failed antiretrovirals(3-4 drugs and ≥ 5 drugs versus 0-2 drugs: AOR = 1.42 and 2.38 respectively); calendar year (AOR = 0.80 per year) and plasma HIV-RNA copies/ml at therapy change (≥ 4 log versus < 2 log: AOR = 1.55). The probability of taking an experimental antiretroviral through a trial was significantly lower for patients suffering from liver co-morbidity(AOR = 0.65) and for those who experienced 3-4 drugs (vs naive) (AOR = 0.55), while it increased for multi-treated patients(AOR = 2.60). The probability to start an experimental antiretroviral trough an EAP progressively increased with the increasing number of experienced and of failed drugs and also increased for patients with liver co-morbidity (AOR = 1.44; p = 0.053). and for male homosexuals (vs heterosexuals: AOR = 1.67). Variability of the random effect associated to clinical units was statistically significant (p < 0.001) although no association was found with specific characteristics of clinical unit examined.

Conclusions

Among patients with HIV infection in Italy, access to experimental antiretrovirals seems to be influenced mainly by exhaustion of treatment options and not by socio-demographic factors.

HIV treatment as prevention: systematic comparison of mathematical models of the potential impact of antiretroviral therapy on HIV incidence in South Africa

BACKGROUND

Many mathematical models have investigated the impact of expanding access to antiretroviral therapy (ART) on new HIV infections. Comparing results and conclusions across models is challenging because models have addressed slightly different questions and have reported different outcome metrics. This study compares the predictions of several mathematical models simulating the same ART intervention programmes to determine the extent to which models agree about the epidemiological impact of expanded ART.

METHODS AND FINDINGS

Twelve independent mathematical models evaluated a set of standardised ART intervention scenarios in South Africa and reported a common set of outputs. Intervention scenarios systematically varied the CD4 count threshold for treatment eligibility, access to treatment, and programme retention. For a scenario in which 80% of HIV-infected individuals start treatment on average 1 y after their CD4 count drops below 350 cells/µl and 85% remain on treatment after 3 y, the models projected that HIV incidence would be 35% to 54% lower 8 y after the introduction of ART, compared to a counterfactual scenario in which there is no ART. More variation existed in the estimated long-term (38 y) reductions in incidence. The impact of optimistic interventions including immediate ART initiation varied widely across models, maintaining substantial uncertainty about the theoretical prospect for elimination of HIV from the population using ART alone over the next four decades. The number of person-years of ART per infection averted over 8 y ranged between 5.8 and 18.7. Considering the actual scale-up of ART in South Africa, seven models estimated that current HIV incidence is 17% to 32% lower than it would have been in the absence of ART. Differences between model assumptions about CD4 decline and HIV transmissibility over the course of infection explained only a modest amount of the variation in model results.

CONCLUSIONS

Mathematical models evaluating the impact of ART vary substantially in structure, complexity, and parameter choices, but all suggest that ART, at high levels of access and with high adherence, has the potential to substantially reduce new HIV infections. There was broad agreement regarding the short-term epidemiologic impact of ambitious treatment scale-up, but more variation in longer term projections and in the efficiency with which treatment can reduce new infections. Differences between model predictions could not be explained by differences in model structure or parameterization that were hypothesized to affect intervention impact.

Trends in virological and clinical outcomes in individuals with HIV-1 infection and virological failure of drugs from three antiretroviral drug classes: a cohort study

BACKGROUND

Limited treatment options have been available for people with HIV who have had virological failure of the three original classes of HIV antiretroviral drugs-so-called triple-class virological failure (TCVF). However, introduction of new drugs and drug classes might have improved outcomes. We aimed to assess trends in virological and clinical outcomes for individuals with TCVF in 2000-09.

METHODS

In our cohort study, we analysed data for adults starting antiretroviral therapy from 1998 in cohorts participating in the PLATO II project, which is part of COHERE, a collaboration of European cohorts. TCVF was defined as virological failure to at least two nucleoside reverse transcriptase inhibitors, one non-nucleoside reverse-transcriptase inhibitor, and one ritonavir-boosted protease inhibitor, with virological failure of a drug defined as one viral-load measurement of greater than 500 copies per mL after at least 4 months of continuous use. We used multivariable generalised estimating equation logistic models and Poisson regression models to study trends in virological suppression and incidence of AIDS or death after TCVF. We adjusted for sex, transmission group, age, AIDS status, CD4 cell count, plasma viral loads at TCVF, achievement of virological response (<50 copies per mL), and number of drug failures before TCVF.

FINDINGS

28 of 33 cohorts in COHERE contributed data to the PLATO II project, of which four had no participants eligible for inclusion in this study. 2476 (3%) of 91 764 participants from the remaining 24 cohorts had TCVF and at least one viral load measurement in 2000-09. The proportion of patients with virological response after TCVF increased from 19·5% in 2000 to 57·9% in 2009 (adjusted p<0·0001). Incidence of AIDS decreased from 7·7 per 100 person-years in 2000-02 to 2·3 in 2008 and 1·2 in 2009 (adjusted p<0·0001). Mortality decreased from 4·0 per 100 person-years between 2000 and 2002 to 1·9 in 2007 and 1·4 in 2008 (unadjusted p=0·023), but the trend was not significant after adjustment (p=0·22).

INTERPRETATION

A substantial improvement in viral load suppression and accompanying decrease in the rates of AIDS in people after extensive failure to drugs from the three original antiretroviral classes during 2000-09 was probably mainly driven by availability of newer drugs with better tolerability and ease of use and small cross-resistance profiles, suggesting the public health benefit of the introduction of new drugs.

Long-term immunological outcomes in treated HIV-infected individuals in high-income and low-middle income countries

PURPOSE OF REVIEW

To summarize the recent findings on long-term (at least 3-4 years) immunological responses to combination antiretroviral therapy (cART) and to compare and contrast the findings between cohorts from high-income and low-middle income countries (LMICs).

RECENT FINDINGS

Cohort studies from high-income settings suggest that a majority of treated HIV-infected patients who maintain suppressed HIV viremia experience a gradual increase in CD4 cell counts for several years to normal levels. However, those who start cART at CD4 cell counts less than 200 cells/μl (as opposed to CD4 cell counts>200 cells/μl) spend several more years below the safe CD4 cell count threshold of 500 cells/μl. Cohorts from LMICs also report persistent improvements in CD4+ cell counts over first 4-5 years of follow-up. However, low-CD4 cell counts (<200 cells/μl) at the start of cART, high early mortality, and loss to follow-up in LMICs settings suggest that the observed optimistic responses may be affected by survivorship bias and should be cautiously interpreted as the optimal, rather than an average, response in LMICs populations.

SUMMARY

LMICs cohorts report similar immunological responses to cART as high-income countries in first 4-5 years of follow-up. Sustaining success in these settings is dependent on timely access to first-line and future cART options, efforts to reduce loss to follow-up, and implementation of treatment guidelines. Cohorts from LMICs are encouraged to continue improving treatment programs and to continue reporting outcomes over the next decade, as surveillance for potential future blunting in responses.

Viral suppression rates in salvage treatment with raltegravir improved with the administration of genotypic partially active or inactive nucleoside/tide reverse transcriptase inhibitors

BACKGROUND

Nucleoside reverse transcriptase inhibitors (NRTIs) are often administered in salvage therapy even if genotypic resistance tests (GRTs) indicate high-level resistance, but little is known about the benefit of these additional NRTIs.

METHODS

The effect of <2 compared with 2 NRTIs on viral suppression (HIV-1 RNA < 50 copies/mL) at week 24 was studied in salvage patients receiving raltegravir. Intent-to-treat and per-protocol analyses were performed; last observation carried forward imputation was used to deal with missing information. Logistic regressions were weighted to create a pseudopopulation in which the probability of receiving <2 and 2 NRTIs was unrelated to baseline factors predicting treatment response.

RESULTS

One-hundred thirty patients were included, of whom 58.5% (n = 76) received <2 NRTIs. NRTIs were often replaced by other drug classes. Patients with 2 NRTIs received less additional drug classes compared with patients with <2 NRTIs [median (IQR): 1 (1-2) compared with 2 (1-2), P Wilcoxon < 0.001]. The activity of non-NRTI treatment components was lower in the 2 NRTIs group compared with the <2 NRTIs group [median (IQR) genotypic sensitivity score: 2 (1.5-2.5) compared with 2.5 (2-3), P Wilcoxon < 0.001]. The administration of <2 NRTIs was associated with a worse viral suppression rate at week 24. The odds ratios were 0.34 (95% confidence interval: 0.13 to 0.89, P = 0.027) and 0.19 (95% confidence interval: 0.05 to 0.79, P = 0.023) when performing the last observation carried forward and the per-protocol approach, respectively.

CONCLUSIONS

Our findings showed that partially active or inactive NRTIs contribute to treatment response, and thus the use of 2 NRTIs in salvage regimens that include raltegravir seems warranted.

Added value of deep sequencing relative to population sequencing in heavily pre-treated HIV-1-infected subjects

OBJECTIVE

To explore the potential of deep HIV-1 sequencing for adding clinically relevant information relative to viral population sequencing in heavily pre-treated HIV-1-infected subjects.

METHODS

In a proof-of-concept study, deep sequencing was compared to population sequencing in HIV-1-infected individuals with previous triple-class virological failure who also developed virologic failure to deep salvage therapy including, at least, darunavir, tipranavir, etravirine or raltegravir. Viral susceptibility was inferred before salvage therapy initiation and at virological failure using deep and population sequencing genotypes interpreted with the HIVdb, Rega and ANRS algorithms. The threshold level for mutant detection with deep sequencing was 1%.

RESULTS

7 subjects with previous exposure to a median of 15 antiretrovirals during a median of 13 years were included. Deep salvage therapy included darunavir, tipranavir, etravirine or raltegravir in 4, 2, 2 and 5 subjects, respectively. Self-reported treatment adherence was adequate in 4 and partial in 2; one individual underwent treatment interruption during follow-up. Deep sequencing detected all mutations found by population sequencing and identified additional resistance mutations in all but one individual, predominantly after virological failure to deep salvage therapy. Additional genotypic information led to consistent decreases in predicted susceptibility to etravirine, efavirenz, nucleoside reverse transcriptase inhibitors and indinavir in 2, 1, 2 and 1 subject, respectively. Deep sequencing data did not consistently modify the susceptibility predictions achieved with population sequencing for darunavir, tipranavir or raltegravir.

CONCLUSIONS

In this subset of heavily pre-treated individuals, deep sequencing improved the assessment of genotypic resistance to etravirine, but did not consistently provide additional information on darunavir, tipranavir or raltegravir susceptibility. These data may inform the design of future studies addressing the clinical value of minority drug-resistant variants in treatment-experienced subjects.

Risk of triple-class virological failure in children with HIV: a retrospective cohort study

BACKGROUND

In adults with HIV treated with antiretroviral drug regimens from within the three original drug classes (nucleoside or nucleotide reverse transcriptase inhibitors [NRTIs], non-NRTIs [NNRTIs], and protease inhibitors), virological failure occurs slowly, suggesting that long-term virological suppression can be achieved in most people, even in areas where access is restricted to drugs from these classes. It is unclear whether this is the case for children, the group who will need to maintain viral suppression for longest. We aimed to determine the rate and predictors of triple-class virological failure to the three original drugs classes in children.

METHODS

In the Collaboration of Observational HIV Epidemiological Research Europe, the rate of triple-class virological failure was studied in children infected perinatally with HIV who were aged less than 16 years, starting antiretroviral therapy (ART) with three or more drugs, between 1998 and 2008. We used Kaplan-Meier and Cox regression methods to investigate the risk and predictors of triple-class virological failure after ART initiation.

FINDINGS

Of 1007 children followed up for a median of 4·2 (IQR 2·4-6·5) years, 237 (24%) were triple-class exposed and 105 (10%) had triple-class virological failure, of whom 29 never had a viral-load measurement less than 500 copies per mL. Incidence of triple-class virological failure after ART initiation increased with time, and risk by 5 years after ART initiation was 12·0% (95% CI 9·4-14·6). In multivariate analysis, older age at ART initiation was associated with increased risk of failure (p=0·02). Of 686 children starting ART with NRTIs and either a NNRTI or ritonavir-boosted protease inhibitor, the rate of failure was higher than in adults with heterosexually transmitted HIV (hazard ratio 2·2 [95% CI 1·6-3·0, p<0·0001]).

INTERPRETATION

Findings highlight the challenges of attaining long-term viral suppression in children who will be taking life-long ART. Early identification of children not responding to ART, adherence support, particularly for children and adolescents aged 13 years or older starting ART, and ART simplification strategies are all needed to attain and sustain virological suppression.

FUNDING

UK Medical Research Council award G0700832.

Combination antiretroviral therapy

Combination antiretroviral therapy (cART) was one of the greatest achievements in medicine in the twentieth century. It has rapidly evolved during the last 10 years from suboptimal monotherapy to an effective triple therapy that can change the natural history of HIV-1 infection from a deadly disease to a chronic, manageable condition. However, a dreadful toll of long-term toxicity was experienced by HIV-1-infected patients in the cART era. We have recently entered in a new phase of cART, in which efficacy has been increased and toxicity minimized. Currently, the greatest challenge is to make cART available to everybody who needs it with the future prospects of HIV-1 eradication.

Predictors for the emergence of the 2 multi-nucleoside/nucleotide resistance mutations 69 insertion and Q151M and their impact on clinical outcome in the Swiss HIV cohort study

The 69 insertion and Q151M mutations are multi-nucleoside/nucleotide resistance mutations (MNR). The prevalence among 4078 antiretroviral therapy (ART)-experienced individuals was <1.3%. Combined ART fully prevented MNR in subtype B infections. Case-control studies were performed to identify risk factors. Control subjects were patients with ≥ 3 thymidine-analogue mutations. The 69 insertion study (27 control subjects, 14 case patients) identified didanosine exposure as a risk (odds ratio, 5.0 per year; P = .019), whereas the Q151M study (which included 44 control subjects and 25 case patients) detected no associations. Following detection, individuals with Q151M tended to have lower suppression rates and higher mortality rates, relative to control subjects. Additional studies are needed to verify these findings in non-subtype B infections.

Efficacy, tolerability and risk factors for virological failure of darunavir-based therapy for treatment-experienced HIV-infected patients: the Swiss HIV Cohort Study

OBJECTIVES

Darunavir was designed for activity against HIV resistant to other protease inhibitors (PIs). We assessed the efficacy, tolerability and risk factors for virological failure of darunavir for treatment-experienced patients seen in clinical practice.

METHODS

We included all patients in the Swiss HIV Cohort Study starting darunavir after recording a viral load above 1000 HIV-1 RNA copies/mL given prior exposure to both PIs and nonnucleoside reverse transcriptase inhibitors. We followed these patients for up to 72 weeks, assessed virological failure using different loss of virological response algorithms and evaluated risk factors for virological failure using a Bayesian method to fit discrete Cox proportional hazard models.

RESULTS

Among 130 treatment-experienced patients starting darunavir, the median age was 47 years, the median duration of HIV infection was 16 years, and 82% received mono or dual antiretroviral therapy before starting highly active antiretroviral therapy. During a median patient follow-up period of 45 weeks, 17% of patients stopped taking darunavir after a median exposure of 20 weeks. In patients followed beyond 48 weeks, the rate of virological failure at 48 weeks was at most 20%. Virological failure was more likely where patients had previously failed on both amprenavir and saquinavir and as the number of previously failed PI regimens increased.

CONCLUSIONS

As a component of therapy for treatment-experienced patients, darunavir can achieve a similar efficacy and tolerability in clinical practice to that seen in clinical trials. Clinicians should consider whether a patient has failed on both amprenavir and saquinavir and the number of failed PI regimens before prescribing darunavir.

Antiretroviral therapy and management of HIV infection

Antiretroviral therapy of HIV infection has changed a uniformly fatal into a potentially chronic disease. There are now 17 drugs in common use for HIV treatment. Patients who can access and adhere to combination therapy should be able to achieve durable, potentially lifelong suppression of HIV replication. Despite the unquestioned success of antiretroviral therapy, limitations persist. Treatment success needs strict lifelong drug adherence. Although the widely used drugs are generally well tolerated, most have some short-term toxic effects and all have the potential for both known and unknown long-term toxic effects. Drug and administration costs limit treatment in resource-poor regions, and are a growing concern even in resource rich settings. Finally, complete or near complete control of viral replication does not fully restore health. Long-term treated patients who are on an otherwise effective regimen often show persistent immune dysfunction and have higher than expected risk for various non-AIDS-related complications, including heart, bone, liver, kidney, and neurocognitive diseases.