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

A characterization of the HIV population with limited/exhausted treatment options: a multicenter Belgian study

OBJECTIVE

Describe the prevalence and characteristics of people living with HIV (PLWH) in Belgium with limited/exhausted treatment options.

METHODS

A cross-sectional, multicenter study involving adult treatment-experienced individuals with limited/exhausted treatment options defined as having a multi-drug resistant HIV-1 or a history of multiple treatment changes. The primary outcome was to determine the prevalence of these individuals and classify them based on their two most recent consecutive HIV-1 viral loads (VLs): suppressed (2 VLs < 50 copies/mL), intermediate (≥1 VL between 50-200 copies/mL), or unsuppressed (2 VLs > 200 copies/mL). Secondary outcome was to characterize the participants included in this analysis.

RESULTS

There were 119 individuals included (prevalence of 0.97%; 119 of 12 282 in care). The majority were aged > 50 years (88.2%), women represented 35.3%, and individuals were primarily White (54.7%). Median (IQR) CD4+ T-cell count was 635 (400-875) cells/µL and most (42%) were on a 3-drug ART regimen. Overall, 87.4% were classified as suppressed, 9.2% as intermediate, and 3.4% as unsuppressed. On multivariable analysis, CD4+ T-cell count < 200 cells/µL was associated with being classified as intermediate or unsuppressed (p = 0.004).

CONCLUSION

In this analysis of PLWH in Belgium, individuals with limited/exhausted treatment options represented a small fraction. Most were on a 3-drug ART regimen, were virologically suppressed, and had a CD4+ T-cell count within normal range. A small proportion were not virologically suppressed while others, despite being suppressed, were on ≥ 4-drug ART regimens. As such, new therapeutic options are needed to achieve and maintain virologic suppression in such individuals while decreasing their pill burden.

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.

Trends and predictors of HIV-1 acquired drug resistance in Minas Gerais, Brazil: 2002-2012

Several studies show that the prevalence of multidrug-resistant HIV-1 virus is declining over time. A retrospective cohort study was carried out to evaluate the trends of drug resistance in antiretroviral treatment-exposed individuals in a state of a middle-income country, Minas Gerais, southeast region of Brazil. We analyzed 2115 HIV-1 sequences from 2002 up to 2012, from 52 cities of Minas Gerais. The groups were analyzed according to the definitions: "IAS - 3 class mutations", if ≥1 drug resistance mutation from IAS 2015 list (DRM) was present in each class; "No fully susceptible drugs" as the absence of any fully susceptible drug in Stanford algorithm; and "GSS≥2″, when a maximum calculated GSS (genotypic susceptibility score) was ≥2 or ≥3, counting only drugs available in Brazil and USA at given calendar years. Time trends of resistance were analyzed by Cochran-Armitage test. We observed a decrease in the rate resistance mutations for PI, NRTI, "IAS - 3 class mutations", and "No fully susceptible drugs" over these 11 years, from 69.2% to 20.7%, 92.3% to 90.2%, 46.2% to 22.5%, and 12.8% to 5.7%, respectively (p<0.05). Resistance to NNRTI increased from 74.4% to 81.6%, mainly because of K103N mutation. The GSS score ≥2 increased during the years from 35.9% to 87.3% (p<0.001). We demonstrate that resistance to PI and to the three main classes simultaneously are declining, although the number of patients on of antiretroviral therapy has doubled in the last ten years in Brazil (125,000 in 2002 to 400,000 in 2014). Broader resistance testing and the availability of more therapeutic options might have influenced this decline. The increase in NNRTI resistance can limit this class as first line treatment in Brazil in the future.

Incidence and risk factors of HPV-related and HPV-unrelated Head and Neck Squamous Cell Carcinoma in HIV-infected individuals

OBJECTIVES

To examine the risk and trends of HPV-related and HPV-unrelated Head and Neck Squamous Cell Carcinoma (HNSCC) in HIV-infected individuals and assess whether immunosuppression (measured through CD4 cell count) and other risk factors impact HNSCC risk.

MATERIALS AND METHODS

Incident HNSCCs at HPV-related and HPV-unrelated anatomic sites were detected in HIV-infected participants from pooled data from 17 prospective studies in the North American AIDS Cohort Collaboration on Research and Design (NA-ACCORD) between 1996 and 2009. HNSCC cases were validated using chart review or cancer registry matching. Risk factors for incident HPV-related and HPV-unrelated HNSCC were explored using mixed effects Poisson regression in a full prospective analysis, and the effect of CD4 prior to cancer diagnosis was examined in a nested case control analysis.

RESULTS

66 HPV-related and 182 HPV-unrelated incident HNSCCs were detected among 82,375 HIV-infected participants. Standardized incidence ratios (SIRs) for both HPV-related (SIR=3.2, 95%CI=2.5-3.4) and HPV-unrelated (SIR=3.0, 95%CI=2.5-4.1) HNSCC were significantly elevated in HIV-infected individuals compared with the US general population. Between 1996 and 2009, the age-standardized HPV-related HNSCC incidence increased non-significantly from 6.8 to 11.4per 100,000 person-years (p-trend=0.31) while the age-standardized incidence of HPV-unrelated HNSCC decreased non-significantly from 41.9 to 29.3 per 100,000 person-years (p-trend=0.16). Lower CD4 cell count prior to cancer diagnosis was significantly associated with increased HPV-related and HPV-unrelated HNSCC risk.

CONCLUSION

The standardized incidence of HPV-related and HPV-unrelated HNSCC are both elevated in HIV-infected individuals. Immunosuppression may have a role in the development of both HPV-related and HPV-unrelated HNSCC.

Community HIV-1 drug resistance is associated with transmitted drug resistance

OBJECTIVES

As community viral load (CVL) measurements are associated with the incidence of new HIV-1 infections in a population, we hypothesized that similarly measured community drug resistance (CDR) could predict the prevalence of transmitted drug resistance (TDR).

METHODS

Between 2001 and 2011, the prevalences of HIV-1 drug resistance for patients with established infection receiving HIV care (i.e. CDR) and TDR in recently infected patients were determined in San Diego. At each position in HIV-1 reverse transcriptase (RT) and protease (pro), drug resistance was evaluated both as the overall prevalence of resistance-associated mutations and by weighting each resistance position to the concurrent viral load of the patient and its proportion to the total viral load of the clinic (CVL). The weighting was the proportion of the CVL associated with patients identified with resistance at each residue. Spearman ranked correlation coefficients were used to determine associations between CDR and TDR.

RESULTS

We analysed 1088 resistance tests for 971 clinic patients and baseline resistance tests for 542 recently infected patients. CDR at positions 30, 46, and 88 in pro was associated with TDR between 2001 and 2011. When CDR was weighted by the viral load of patients, CDR was associated with TDR at position 103 in RT. Each of these associations was corroborated at least once using shorter measurement intervals.

CONCLUSIONS

Despite evaluation of a limited percentage of chronically infected patients in San Diego, CDR correlated with TDR at key resistance positions and therefore may be a useful tool with which to predict the prevalence of TDR.

Risk of virological failure and drug resistance during first and second-line antiretroviral therapy in a 10-year cohort in Senegal: results from the ANRS 1215 cohort

BACKGROUND

In 1998, Senegal launched one of Africa's first antiretroviral therapy (ART) programs. Since then, the number of treated patients in Africa has substantially increased thanks to simplification in treatment management. Although good outcomes over the first years of ART have been observed in sub-Saharan Africa, little is known about the long-term (>5 years) risks of virological failure and drug resistance and about second-line treatment response.

METHODS

Patients from the ANRS-1215 cohort in Senegal, started with either one nonnucleoside reverse transcriptase inhibitor or indinavir, a first-generation nonboosted protease inhibitor, followed for >6 months and having >1 viral load (VL) measurement were included. Virological failure was defined as 2 consecutive VL measurements >1000 copies/mL.

RESULTS

Of the 366 patients included, 89% achieved a VL <500 copies/mL. The risk of virological failure at 12, 24, and 60 months was 5%, 16%, and 25%, being higher in younger patients (P = 0.05), those receiving a protease inhibitor-containing regimen (P = 0.05), and those with lower adherence (P = 0.03). The risk of resistance to any drug at 12, 24, and 60 months was 3%, 11%, and 18%. After virological failure, 60% of the patients were switched to second-line treatments. Although 81% of the patients achieved virological success, the risk of virological failure was 27% at 24 months, mostly in patients with multiple resistances.

CONCLUSIONS

In this cohort, virological outcomes for first-line treatments were good compared with those from high-resource settings. However, the rate of virological failure for second-line treatment was high, probably because of accumulation of resistances.

Trends in Decline of Antiretroviral Resistance among ARV-Experienced Patients in the HIV Outpatient Study: 1999-2008

Background. Little is known about temporal trends in frequencies of clinically relevant ARV resistance mutations in HIV strains from U.S. patients undergoing genotypic testing (GT) in routine HIV care. Methods. We analyzed cumulative frequency of HIV resistance among patients in the HIV Outpatient Study (HOPS) who, during 1999-2008 and while prescribed antiretrovirals, underwent GT with plasma HIV RNA >1,000 copies/mL. Exposure ≥4 months to each of three major antiretroviral classes (NRTI, NNRTI and PI) was defined as triple-class exposure (TCE). Results. 906 patients contributed 1,570 GT results. The annual frequency of any major resistance mutations decreased during 1999-2008 (88% to 79%, P = 0.05). Resistance to PIs decreased among PI-exposed patients (71% to 46%, P = 0.010) as exposure to ritonavir-boosted PIs increased (6% to 81%, P < 0.001). Non-significant declines were observed in resistance to NRTIs among NRTI-exposed (82% to 67%), and triple-class-resistance among TCE patients (66% to 41%), but not to NNRTIs among NNRTI-exposed. Conclusions. HIV resistance was common but declined in HIV isolates from subgroups of ARV-experienced HOPS patients during 1999-2008. Resistance to PIs among PI-exposed patients decreased, possibly due to increased representation of patients whose only PI exposures were to boosted PIs.