HIV-1 resistance and virological failure to treatment with the integrase inhibitors bictegravir, cabotegravir, and dolutegravir: a systematic literature review.

We describe and analyze resistance-associated mutations (RM) and virological failures (VF) on antiretroviral therapy using the latest approved integrase inhibitors (INIs) dolutegravir (DTG), bictegravir (BIC), and cabotegravir (CAB), together with their companion drugs in fixed-dose formulations: BIC/emtricitabine/tenofovir; CAB/rilpivirine; DTG/abacavir/lamivudine; DTG/emtricitabine/tenofovir; and DTG/lamivudine. Systematic literature searches were conducted in PubMed and other electronic databases for clinical studies published between January 2010 and May 2023, according to preferred reporting items for systematic reviews and meta-analyses guidelines (PRISMA), which analyzed VFs and RMs of INIs. Fifty clinical studies were included in the synthesis. VF in antiretroviral treatment (ART)-naïve patients occurred in 0.7-4.0%, 0.6-1.4%, and 0.6-9.0% of patients treated with DTG, BIC, and CAB, respectively. VF was reported in patients with previous ART in 0-8.1%, 0-2.0%, and 0.4-2.3% of those treated with DTG, BIC, and CAB, respectively. RMs were detected in ART-naïve patients in only one study with DTG (0.3%), none of the studies with BIC, and three of the studies with CAB (0.1-5.4%). In ART-experienced patients, RMs were detected in 0-1.9% of DTG-treated patients. No cases of RM were detected in the 11 BIC studies reviewed. In the case of CAB, RMs were detected in eight studies, ranging from 0.3% to 1.9% of patients. In conclusion, RM rates in the studies reviewed were generally low using the latest INIs. This review identified BIC as the INI with the lowest number of observed VF and lack of RM.

Genetic landscape for majority and minority HIV-1 drug resistance mutations in antiretroviral therapy naive patients in Accra, Ghana.

Background: The successful detection of drug-resistance mutations (DRMs) in HIV-1 infected patients has improved the management of HIV infection. Next-generation sequencing (NGS) to detect low-frequency mutations is predicted to be useful for efficiently testing minority drug resistance mutations, which could contribute to virological failure. This study employed Sanger sequencing and NGS to detect and compare minority and majority drug resistance mutations in HIV-1 strains in treatment-naive patients from Ghana. Method: From a previous study, 20 antiretroviral therapy (ART)-naive participants were selected for a cross-sectional study. Sanger sequencing and NGS techniques were used to detect the majority and minority HIV drug resistance (HIVDR) mutations, respectively, in the protease (PR) and partial reverse transcriptase (RT) genes. NGS detected mutations at 1 % and 5 % frequencies and Sanger sequencing at ≥20 % frequencies. The sequences obtained from NGS and Sanger sequencing platforms were submitted to the Stanford HIV drug resistance database for subtyping, mutation identification, and interpretations. Results: Sequences from the twenty participants where the CRF02_AG was the predominant strain (16, 80 %) were analyzed. NGS detected 25 mutations in the RT and PR genes, compared to 21 mutations by Sanger sequencing. Minority DRMs were detected at the prevalence of 55.0 % with NGS against 35 % DRMs by Sanger sequencing. One of the patients had eight different HIVDR variants, with two minority variants. These mutations were directed against PI (K20I and D30DN), NNRTI (Y181C, M23LM and V108I) and NRTI (K65R, M184I, and D67N). Conclusion: The study affirms the usefulness of genomic sequencing for drug resistance testing in HIV. It further shows that Sanger sequencing alone may not be adequate to detect mutations and that NGS capacity should be developed and deployed in the Ghanaian clinical settings for patients living with HIV.

CRF08_BC subtype is more prone to ART failure and new-generation NNRTI-resistance under long-term first-line ART.

OBJECTIVE: To investigate the characteristics of drug resistance mutations (DRMs) and their contextual influence on drug susceptibility in CRF07_BC and CRF_08BC subtypes. METHODS: Patients with virological failure were genotyped using phylogenetic analysis. DRMs and susceptibility to antiretroviral drugs were analysed using the Stanford University HIV Drug Resistance Database. RESULTS: Six HIV subtypes were identified among 1296 successfully amplified sequences, with the CRF07_BC subtype prevailing at a rate of 91.7%, followed by CRF08_BC. Overall, the CRF07_BC and CRF08_BC subtypes were similar in the distribution and frequency of DRMs, the most common DRMs were K103N and M184V. However, among patients with antiretroviral therapy duration of ≥3 y who developed resistance, CRF08_BC exhibited a higher mutation frequency at sites 184, 138, 221, and 188 (Chi-square test, P < 0.05), and compared with CRF07_BC, patients with CRF08_BC had higher prevalence of abacavir, emtricitabine, lamivudine, doravirine, etravirine, and rilpivirine resistance. Moreover, there was an increased prevalence of cross-resistance between efavirenz/nevirapine and new-generation NNRTIs in patients with CRF08_BC; doravirine (r = 1.0), rilpivirine (r = 0.93), and etravirine (r = 0.86) resistance highly correlated with efavirenz/nevirapine. CONCLUSIONS: The present study provides valuable insights into the profile of DRMs and resistance patterns in patients with CRF07_BC and CRF08_BC experiencing treatment failure in Butuo. These findings have the potential to contribute to future strategies for HIV control and treatment.

Enhanced adherence counselling outcomes among people living with HIV with virological failure: Single-centre experience in Pune, India.

OBJECTIVES: World Health Organization has recommended enhanced adherence counselling (EAC) for people living with HIV (PLHIV) with virological failure. This study aimed to assess the outcomes of EAC and its associated factors among PLHIV with virological failure. METHODS: Data collected between March 2020 and February 2022 on viral load (VL) testing at antiretroviral therapy (ART) centre in Pune, India were reviewed. PLHIV with viral load ≥1000 copies/ml followed by three EAC sessions and a repeat viral load test were included. Multivariate logistic regression analysis was used to assess the factors associated with virological suppression (<1000 copies/ml). RESULTS: Of 170 PLHIV, 81 (47.6%) showed virological suppression. Being literate (p = 0.027), females (p = 0.021), on second-line ART regimen (p = 0.020), and with EAC initiation within a month (p = 0.016) were significantly associated with virological suppression. No association was found between reported barriers to treatment adherence and virological suppression. DISCUSSION: Early initiation of EAC is crucial for virological suppression among PLHIV with high viral load. It is important to highlight the significance of treatment adherence among individuals on first-line ART regimen. The use of effective visual tools during EAC sessions may help in achieving virological suppression among those with low literacy.

Factors Affecting Virological Failure in Children Receiving First-Line Antiretroviral Therapy in Ethiopian Healthcare Facilities: A Retrospective Analysis.

Background: The causes of virological failure are poorly recognized and investigated. This study aimed to identify determinant factors of viral failure in children taking first-line ART at a randomly selected federal hospital in Addis Ababa, Ethiopia. Methods: A facility-based unmatched case-control study was carried out from May 10, 2022, to July 20, 2022, G.C. among HIV-infected children on first-line antiretroviral therapy. There were 209 HIV-positive youngsters in the study's overall sample size, comprising 53 cases and 156 controls. Data was gathered by chart review using an organized checklist in English. The data were entered using Epi-data 4.2 and exported into SPSS version 24 for analysis. The relationship between each explanatory variable and the result variable was described using both bivariate and multivariate analysis. An adjusted odds ratio with 95% confidence intervals was conducted, and a p-value <0.05 was considered statistically significant. Results: Being male (AOR= 4.504; 95% CI: 1.498, 13.539), duration on ART exceeding 47 months (AOR=40.6; 95% CI:9.571,172.222), fair and poor drug adherence (AOR=16.348; 95% CI:4.690,56.990), missed clinical appointments (AOR = 3.177; 95% CI: 1.100-9.174), and baseline WHO clinical stage 4 disease (AOR = 6.852; 95% CI: 1.540-30.49) were associated with an increased risk of virological failure. Conversely, a history of drug change and a CD4 count ranging from 250 to 500 cells/mm3 were significantly protective factors (AOR = 0.071; 95% CI: 0.024-0.214 and AOR=0.118; 95% CI: 0.030, 0.464, respectively). Conclusion: Being male, duration on ART >47 months, fair and poor adherence, missed clinical appointments, and baseline WHO Stage 4 are factors that increase the odds of virological failure. History of ART Drug change and a CD4 count between 250 and 500 cells/mm3 are factors that decrease the odds of virological failure.

Attrition Rates in HIV Viral Load Monitoring and Factors Associated With Overdue Testing Among Children Within South Africa's Antiretroviral Treatment Program: Retrospective Descriptive Analysis.

BACKGROUND: Numerous studies in South Africa have reported low HIV viral load (VL) suppression and high attrition rates within the pediatric HIV treatment program. OBJECTIVE: Using routine laboratory data, we evaluated HIV VL monitoring, including mobility and overdue VL (OVL) testing, within 5 priority districts in South Africa. METHODS: We performed a retrospective descriptive analysis of National Health Laboratory Service (NHLS) data for children and adolescents aged 1-15 years having undergone HIV VL testing between May 1, 2019, and April 30, 2020, from 152 facilities within the City of Johannesburg, City of Tshwane, eThekwini, uMgungundlovu, and Zululand. HIV VL test-level data were deduplicated to patient-level data using the NHLS CDW (Corporate Data Warehouse) probabilistic record-linking algorithm and then further manually deduplicated. An OVL was defined as no subsequent VL determined within 18 months of the last test. Variables associated with the last VL test, including age, sex, VL findings, district type, and facility type, are described. A multivariate logistic regression analysis was performed to identify variables associated with an OVL test. RESULTS: Among 21,338 children and adolescents aged 1-15 years who had an HIV VL test, 72.70% (n=15,512) had a follow-up VL test within 18 months. Furthermore, 13.33% (n=2194) of them were followed up at a different facility, of whom 3.79% (n=624) were in a different district and 1.71% (n=281) were in a different province. Among patients with a VL of ≥1000 RNA copies/mL of plasma, the median time to subsequent testing was 6 (IQR 4-10) months. The younger the age of the patient, the greater the proportion with an OVL, ranging from a peak of 52% among 1-year-olds to a trough of 21% among 14-year-olds. On multivariate analysis, 2 consecutive HIV VL findings of ≥1000 RNA copies/mL of plasma were associated with an increased adjusted odds ratio (AOR) of having an OVL (AOR 2.07, 95% CI 1.71-2.51). Conversely, patients examined at a hospital (AOR 0.86, 95% CI 0.77-0.96), those with ≥2 previous tests (AOR 0.78, 95% CI 0.70-0.86), those examined in a rural district (AOR 0.63, 95% CI 0.54-0.73), and older age groups of 5-9 years (AOR 0.56, 95% CI 0.47-0.65) and 10-14 years (AOR 0.51, 95% CI 0.44-0.59) compared to 1-4 years were associated with a significantly decreased odds of having an OVL test. CONCLUSIONS: Considerable attrition occurs within South Africa's pediatric HIV treatment program, with over one-fourth of children having an OVL test 18 months subsequent to their previous test. In particular, younger children and those with virological failure were found to be at increased risk of having an OVL test. Improved HIV VL monitoring is essential for improving outcomes within South Africa's pediatric antiretroviral treatment program.

HIV-1 low-level viraemia predicts virological failure in first-line and second-line ART-experienced individuals in India: A retrospective longitudinal study.

OBJECTIVE: To study the prevalence of low-level viraemia (LLV) and its association with virological failure (VF). METHODS: We conducted a retrospective analysis of 3498 participants at YRG CARE, Chennai, India (2013-2018) on antiretroviral therapy (ART) for ≥6 months with two or more plasma viral load (pVL) measurements. Results were stratified for those with pVL <1000 copies/mL: fully suppressed (FS) (pVL <40), low-LLV (pVL 40-199), mid-LLV (pVL 200-399), and high-LLV (pVL 400-999). The study assessed the association with VF (pVL >1000 copies/mL) using Cox proportional hazard model. RESULTS: Among 3498 participants, 2965 (84.8%) were FS and 533 (15.2%) were LLV. During the follow-up, 348 (10%) experienced VF, with 222 (6.3%) experienced after LLV (42% of LLV) and 126 (3.6%) experienced after FS (4.3% of FS). When compared with FS, those with LLV had a greater risk of VF [adjusted hazard ratio (aHR) = 12.7; 95% confidence interval (CI): 10.2-15.9]. First-line participants had a higher VF incidence (aHR = 15.8, 95% CI: 11.4-21.9) than second-line participants (aHR = 5.6, 95% CI: 4.1-7.7). Those with high-LLV had the highest VF risk (aHR = 22.856, 95% CI: 15.204-34.359 vs. aHR = 8.186, 95% CI: 5.564-12.043, for first-line vs. second-line participants, respectively), followed by those with mid-LLV (aHR = 13.375, 95% CI: 8.327-21.483 vs. aHR = 6.261, 95% CI: 4.044-9.695) and low-LLV (aHR = 12.976, 95% CI: 7.974-21.118 vs. aHR = 4.158, 95% CI: 2.826-6.119). CONCLUSIONS: The prevalence of LLV was intermediate in our study population. There was a higher risk of VF among individuals with LLV, and this risk increased with the increasing levels of LLV. Close monitoring of individuals experiencing LLV could help in the early identification of VF.

Rapid Initiation of Antiretroviral Therapy Under the Treat-All Policy Reduces Loss to Follow-Up and Virological Failure in Routine Human Immunodeficiency Virus Care Settings in China: A Retrospective Cohort Study (2016-2022).

Following the World Health Organization's guidelines for rapid antiretroviral therapy (ART) initiation [≤7 days after human immunodeficiency virus (HIV) diagnosis], China implemented Treat-All in 2016 and has made significant efforts to provide timely ART since 2017. This study included newly diagnosed HIV adults from Tianjin, China, between 2016 and 2022. Our primary outcome was loss to follow-up (LTFU) at 12 months after enrollment. The secondary outcome was 12-month virological failure. The association between rapid ART and LTFU, as well as virological failure, was assessed via Cox regression and logistic regression. A total of 896 (19.1%) of 4688 participants received ART ≤7 days postdiagnosis. The rate of rapid ART has increased from 7.5% in 2016 to 33.3% by 2022. The rapid ART group had an LTFU rate of 3.3%, as opposed to 5.0% in the delayed group. The rapid ART group had a much reduced virological failure rate (0.6% vs. 1.8%). Rapid ART individuals had a reduced likelihood of LTFU [adjusted hazard ratio: 0.65, 95% confidence intervals (CI): 0.44-0.96] and virological failure (adjusted odds ratio: 0.35, 95% CI: 0.12-0.80). The real-world data indicated that rapid ART is practicable and beneficial for Chinese people with HIV, providing evidence for its widespread implementation and scaling up.

Outcome of Darunavir-Cobicistat-Based Regimens in HIV-Infected People Who Have Experienced Virological Failure.

Objective: To evaluate the virological outcome of darunavir-cobicistat (DRVc)-based regimens in adults living with HIV who had experienced virological failure (VF) on any previous drug combination. Methods: This was a retrospective cohort study (CSLHIV Cohort) of adults living with HIV who started a DRVc-based regimen with HIV-RNA >50 copies/mL after VF on any previous drug combination. Data on demographics, antiretroviral treatment since HIV diagnosis, and immunological and metabolic parameters from baseline (start of DRVc) to 48 weeks were analyzed in order to assess the cumulative proportion of those who achieved virological success (VS), defined as at least one instance of HIV-RNA <50 copies/mL within 12 months from baseline. Follow-up lasted from the start of the DRVc-based regimen (baseline) to the first instance of HIV-RNA <50 copies/mL, last available visit, or loss to follow-up or death, whichever occurred first. Univariate and multivariate Cox proportional-hazard regression models were used to identify baseline factors associated with VS. Results: A total of 176 individuals were included, and 120 (68.2%) achieved <50 HIV-RNA copies/mL within 12 months since baseline. On multivariate analysis, baseline HDL cholesterol was independently associated with the occurrence of VS (adjusted HR 1.021, 95% CI 1.004-1.038; p=0.014). Among the 120 subjects with VS, 27 (22.5%) had had VF during a median follow-up of 20.8 months since the first undetectable HIV-RNA. Resistance testing after VF was available in two cases, which harboured the HIV variant-bearing protease inhibitor-resistance mutations D30N, I50V, and N88D. During a median follow-up of 38.4 months, 65 of 176 (36.9%) individuals discontinued DRVc for any reason (37 of 120, 30.8%) and achieved VS vs. 28 of 56 (50%) without VS (p=0.019). Time to discontinuation was longer in people with VS (41.5 vs. 23.0 months, p=0.0007). No statistically significant changes were observed in immunological or lipid profiles during follow-up. Conclusion: Most individuals in this study achieved VS within 12 months from the beginning of a DRVc-based regimen; therefore, this treatment represent a viable option for people who have experienced VF on other regimens.

Dolutegravir/Lamivudine Is Noninferior to Continuing Dolutegravir- and Non-Dolutegravir-Based Triple-Drug Antiretroviral Therapy in Virologically Suppressed People With Human Immunodeficiency Virus: DUALING Prospective Nationwide Matched Cohort Study.

Background: Confirming the efficacy of dolutegravir/lamivudine in clinical practice solidifies recommendations on its use. Methods: Prospective cohort study (DUALING) in 24 human immunodeficiency virus (HIV) treatment centers in the Netherlands. HIV RNA-suppressed cases were on triple-drug antiretroviral regimens without prior virological failure or resistance and started dolutegravir/lamivudine. Cases were 1:2 matched to controls on triple-drug antiretroviral regimens by the use of dolutegravir-based regimens, age, sex, transmission route, CD4+ T-cell nadir, and HIV RNA zenith. The primary endpoint was the treatment failure rate in cases versus controls at 1 year by intention-to-treat and on-treatment analyses with 5% noninferiority margin. Results: The 2040 participants were 680 cases and 1380 controls. Treatment failure in the 390 dolutegravir-based cases versus controls occurred in 8.72% and 12.50% (difference: -3.78% [95% confidence interval {CI}, -7.49% to .08%]) by intention-to-treat and 1.39% and 0.80% (difference: 0.59% [95% CI, -.80% to 1.98%]) by on-treatment analyses. The treatment failure risk in 290 non-dolutegravir-based cases was also noninferior to controls. Antiretroviral regimen modifications unrelated to virological failure explained the higher treatment failure rate by intention-to-treat. A shorter time on triple-drug antiretroviral therapy and being of non-Western origin was associated with treatment failure. Treatment failure, defined as 2 consecutive HIV RNA >50 copies/mL, occurred in 4 cases and 5 controls but without genotypic resistance detected. Viral blips occured comparable in cases and controls but cases gained more weight, especially when tenofovir-based regimens were discontinued. Conclusions: In routine care, dolutegravir/lamivudine was noninferior to continuing triple-drug antiretroviral regimens after 1 year, supporting the use of dolutegravir/lamivudine in clinical practice. Clinical Trials Registration: NCT04707326.

Heavily treatment-experienced persons living with HIV currently in care in Italy: characteristics, risk factors, and therapeutic options-the ICONA Foundation cohort study.

OBJECTIVES: Heavily treatment-experienced (HTE) people living with HIV (PLWH) pose unique challenges due to limited antiretroviral treatment (ART) options. Our study aimed to investigate the prevalence and features of HTE individuals followed up in the Italian Cohort Naïve Antiretrovirals (ICONA) cohort as of December 31, 2021. METHODS: HTE were defined based on meeting specific conditions concerning their current ART and their ART history up to December 31, 2021. Descriptive statistics were performed by HTE status. Regression analyses explored factors associated with becoming HTE based on pre-ART patients' characteristics. Cluster dendrogram analysis provided insights into subgroups with inadequate responses based on clusters of differentiation (CD4) counts and viral load (VL) trajectories. RESULTS: Among the 8758 PLWH actively followed in our cohort, 163 individuals (1.9%), mainly female, younger, Italian, and infected through heterosexual contact, met the HTE criteria. A lower CD4 count at ART initiation (odds ratio [OR] 1.60 per 100 cells/mmc lower CD4, 95% confidence interval [CI] 1.06-2.41, P = 0.03) and hepatitis C virus antibody positivity (OR 1.90, 95% CI 1.16-3.11, P = 0.01) were associated with higher HTE risk. Thirty PLWH exhibited ongoing immune-virological failure (18% of the HTE subgroup and 0.003% of the total population). Thirty PLWH exhibited ongoing immune-virological failure (i.e., with a current CD4 count <200 cells/mmc or VL>200 copies/mL). A cluster analysis identified 13 (43%) with a current CD4 count <200 cells/mmc. Also, notably, 19/30 (63%) had major acquired resistance-associated mutations to at least one antiretroviral drug class. CONCLUSIONS: HTE is rare in our cohort and tends to co-exist with major resistance mutations. A focused investigation into treatment history and immuno-virological response is warranted, particularly given the availability of new antiretroviral drugs.

Incidence and predictors of virological failure among children receiving first-line anti-retroviral treatment in public comprehensive specialized hospitals found in Northeast Ethiopia: a retrospective follow-up study.

Background: Despite anti-retroviral treatment coverage in resource-limited countries being highly appreciated, the occurrence of first-line virological failure remains a priority agenda. Therefore, this study serves as an input for evidence of virological failure among children. Objective: This study aimed to assess the incidence and predictors of virological failure among children receiving first-line anti-retroviral treatment in public comprehensive specialized hospitals found in Northeast Ethiopia through a retrospective follow-up study. Methods: A multicenter institution-based retrospective follow-up study was conducted on the medical records of 481 human immunodeficiency virus (HIV)-infected children who were on first-line anti-retroviral therapy from 1 January 2017 to 31 December 2021. Data were retrieved from 15 May to 15 June 2022 at three public comprehensive specialized hospitals. Study participants were recruited using a simple random sampling technique. STATA-14 was used to analyze the data, which was entered using EpiData version 4.6.2.0. The Kaplan-Meier estimator was used to estimate the survival. Both bivariable and multivariable Cox regression models were fitted to identify predictors. Finally, adjusted hazards ratios (AHRs) with 95% confidence intervals (CIs) were computed, and variables with a P-value of <0.05 were considered statistically significant predictors of virological failure. Result: A total of 481 children records were included in the final analysis, with an observed follow-up period of 16,379 person-months. Among these, 60 (12.47%) had developed virological failure, resulting in an overall incidence density rate of 3.67 (95% CI; 2.84, 4.73) per 1000 person-month observations. The hazards of virological failure (VF) among children were found to be increased by being in recent WHO stages III and IV (AHR = 3.688; 95% CI: 1.449-6.388), poor adherence to anti-retroviral treatment (ART) (AHR = 3.506; 95% CI: 1.711-7.234), and living in a rural environment (AHR = 5.013; 95% CI: 1.958-8.351). Conversely, the hazard of VF was reduced by 60% when the age of caregivers was less than 40 years (AHR = 0.405; 0.003-0.449). Conclusion and recommendations: The incidence rate of virological failure was relatively high. Living in a rural area, poor adherence to ART, being in a recent advanced WHO clinical stage, and having a caregiver of 40 years of age or older were all independent predictors of virological failure in children. Patients or parents (caregivers) need to be aware of the importance of strictly adhering to treatment regimens to prevent virological failure.

Predictors of antiretroviral treatment failure to the first line therapy: a cross-sectional study among Iranian HIV-positive adults.

BACKGROUND: HIV virological failure is one of the main problems in HIV-infected patients, and identifying the main predictors of such treatment failure may help in combating HIV/AIDS. METHODOLOGY: This cross-sectional study included 1800 HIV-infected patients with either virological failure or treatment response. HIV viral load, CD4 count, and other tests were performed. Statistical analysis was used to determine the predictors of virological failure. RESULTS: Clinical stage, treatment with reverse transcriptase inhibitors (RTIs), under therapy for three years or more, suboptimal adherence to antiretroviral treatment (ART), age > 40 years, CD4 count < 200 cells/mm3, unemployment, being infected through sex, and the presence of symptoms were the predominant risk factors for virological failure. In addition, 55% of patients who experienced virological failure failed to experience immunological and/or clinical failure. CONCLUSION: As the first study in southern Iran and the second in Iran, Iranian policymakers should focus on intensive counseling and adherence support and emphasize more effective treatment regimens such as protease and integrase inhibitors (PIs and INTIs), to increase the chance of a treatment response to ART. The accuracy of identifying clinical and immunological criteria in resource-limited settings is not promising. The present findings can be used to determine effective measures to control HIV treatment failure and design efficient strategies for the ambitious 95-95-95 plan.

Clinical Relevance of Human Immunodeficiency Virus Low-level Viremia in the Dolutegravir era: Data From the Viral Load Cohort North-East Lesotho (VICONEL).

Background: Human immunodeficiency virus low-level viremia (LLV) is associated with subsequent treatment failure at least with non nucleoside reverse transcriptase inhibitor (NNRTI)-containing antiretroviral therapy. Data on implications of LLV occurring under dolutegravir, which has largely replaced NNRTIs in Africa, are scarce, however. Methods: We included adults with human immunodeficiency virus in Lesotho who had ≥2 viral loads (VLs) taken after ≥6 months of NNRTI- or dolutegravir-based antiretroviral therapy. Within VL pairs, we assessed the association of viral suppression (<50 copies/mL) and low- and high-range LLV (50-199 and 200-999 copies/mL, respectively) with virological failure (≥1000 copies/mL) using a mixed-effects regression model. Participants could contribute VLs to the NNRTI and the dolutegravir group. Results: Among 18 550 participants, 12 216 (65.9%) were female and median age at first VL included was 41.2 years (interquartile range, 33.4-51.5). In both groups, compared with a suppressed VL, odds of subsequent virological failure were higher for low-range LLV (NNRTI: adjusted odds ratio; 95% confidence interval: 1.9; 1.4-2.4 and dolutegravir: 2.1; 1.3-3.6) and high-range LLV (adjusted odds ratio; 95% confidence interval, 4.2; 3.1-5.7 and 4.4; 2.4-7.9). Conclusions: In the dolutegravir era, LLV remains associated with virological failure, endorsing the need for close clinical and laboratory monitoring of those with a VL ≥50 copies/mL.

Virological Failure After Switch to Long-Acting Cabotegravir and Rilpivirine Injectable Therapy: An In-depth Analysis.

BACKGROUND: Long-acting (LA) injectable therapy with cabotegravir (CAB) and rilpivirine (RPV) is currently used as maintenance treatment for human immunodeficiency virus type 1, and has a low risk for virological failure (VF). Although the risk is low, the circumstances and impact of VF in the real-world setting merit further evaluation. METHODS: We performed an in-depth clinical, virological, and pharmacokinetic analysis on the reasons behind and the impact of VF during LA CAB/RPV therapy in 5 cases from the Netherlands. Genotypic resistance testing was performed after the occurrence of VF, and drug plasma (trough) concentrations were measured after VF was established and on any other samples to assess on-treatment drug levels. CAB and RPV drug levels that were below the first quartile of the population cutoff (≤Q1) were considered to be low. RESULTS: Five cases who were eligible for LA CAB/RPV experienced VF despite a low predicted risk at baseline. Genotypic resistance testing revealed extensive selection of nonnucleoside reverse transcriptase inhibitor-associated mutations in all cases, and integrase strand transfer inhibitor mutations in 4 cases. All cases displayed low drug levels of either CAB, RPV, or both during the treatment course, likely contributing to the occurrence of VF. In 3 cases, we were able to identify the potential mechanisms behind these low drug levels. CONCLUSIONS: This is the first in-depth multiple case analysis of VF on LA CAB/RPV therapy in a real-world setting. Our observations stress the need to be aware for (evolving) risk factors and the yield of a comprehensive clinical, virological, and pharmacokinetic approach in case of failure.

Characterization and outcomes of difficult-to-treat patients starting modern first-line ART regimens: Data from the ICONA cohort.

OBJECTIVES: Treatment failures to modern antiretroviral therapy (ART) raise concerns, as they could reduce future options. Evaluations of occurrence of multiple failures to modern ART are missing and their significance in the long run is unclear. METHODS: People with HIV (PWH) in the ICONA cohort who started a modern first-line ART were defined as 'difficult to treat' (DTT) if they experienced ≥1 among: i) ≥2 VF (2 viral loads, VL>200 copies/mL or 1 VL>1000 copies/mL) with or without ART change; ii) ≥2 treatment discontinuations (TD) due to toxicity/intolerance/failure; iii) ≥1 VF followed by ART change plus ≥1 TD due to toxicity/intolerance/failure. A subgroup of the DTT participants were matched to PWH that, after the same time, were non-DTT. Treatment response, analysing VF, TD, treatment failure, AIDS/death, and SNAE (Serious non-AIDS event)/death, were compared. Survival analysis by KM curves and Cox regression models were employed. RESULTS: Among 8061 PWH, 320 (4%) became DTT. Estimates of becoming DTT was 6.5% (95% CI: 5.8-7.4%) by 6 years. DTT PWH were significantly older, with a higher prevalence of AIDS and lower CD4+ at nadir than the non-DTT. In the prospective analysis, DTT demonstrated a higher unadjusted risk for all the outcomes. Once controlled for confounders, significant associations were confirmed for VF (aHR 2.23, 1.33-3.73), treatment failure (aHR 1.70, 1.03-2.78), and SNAE/death (aHR 2.79, 1.18-6.61). CONCLUSION: A total of 6.5% of PWH satisfied our definition of DTT by 6 years from ART starting. This appears to be a more fragile group who may have higher risk of failure.

Bictegravir/emtricitabine/tenofovir alafenamide in paediatrics: Real-life experience from a French cohort (2019-2023).

OBJECTIVES: Although widely recommended, data on bictegravir/emtricitabine/tenofovir alafenamide (BIC/FTC/TAF) efficacy in HIV-1-infected children/adolescents are mainly extrapolated from studies in adults and one paediatric trial in which subjects have good treatment adherence. This study aimed to provide data about the risk of virological failure (VF) and acquired genotypic resistance in children and adolescents receiving BIC/FTC/TAF in a real-world setting. METHODS: This retrospective monocentric study included 74 paediatric patients who received BIC/FTC/TAF during ≥6 months in 2019-2023. VF was defined as not achieving a plasma viral load <50 copies/mL within 6 months of BIC/FTC/TAF initiation or as experiencing virological rebound ≥50 copies/mL. RESULTS: Most patients were antiretroviral therapy (ART)-experienced (93.2%), previously exposed to integrase inhibitors (85.1%) and displayed viral suppression at baseline (67.6%). Their median age was 11.2 years [interquartile range (IQR): 8.8-15.2]. BIC/FTC/TAF introduction reduced treatment burden in most ART-experienced subjects. Genotypic susceptibility score of BIC/FTC/TAF was ≥2 in all cases. Median follow-up was 40 months (IQR: 21-46). VF occurred in 28 people (37.8%), more frequently in the case of VF versus viral suppression at baseline (68% vs. 26%, P = 0.02). BIC/FTC/TAF was interrupted for suspected intolerance in only one case (1.4%). Nucleoside reverse transcriptase inhibitor (NRTI) mutation (T69D/N) emerged in one patient (3.6% of VF) after 47 months of continuous detectable viraemia while on ART. No acquisition of mutations in the integrase gene was observed. CONCLUSION: Because of its high genetic barrier to resistance, BIC/FTC/TAF could be especially useful in the paediatric population, in which the risk of poor treatment adherence and VF is high.

Low-level HIV viraemia during antiretroviral therapy: Longitudinal patterns and predictors of viral suppression.

OBJECTIVES: Our objective was to characterize longitudinal patterns of viraemia and factors associated with viral suppression in people with HIV and low-level viraemia (LLV) during antiretroviral therapy (ART). METHODS: We included people with HIV in the EuResist Integrated Database with LLV following ART initiation after 2005. LLV was defined as two or more consecutive viral load (VL) measurements of 51-199 copies/mL 30-365 days apart after >12 months of ART. Viraemia patterns were analyzed over 24 months. Factors associated with viral suppression at 12 months after LLV episodes were identified using univariable and multivariable logistic regression. RESULTS: Of 25 113 people with HIV, 2474 (9.9%) had LLV. Among 1387 participants with 24 months of follow-up after LLV, 406 (29%) had persistent suppression, 669 (48%) had transient viraemic episodes, 29 (2%) had persistent LLV, and 283 (20%) had virological failure. Following LLV episodes, the proportion with detectable viraemia declined (p for trend <0.001 and 0.034, in the first and second year, respectively). At 12 months, 68% had undetectable VL, which was associated with suppression before LLV (adjusted odds ratio [aOR] 1.7; 95% confidence interval [CI] 1.2-2.4) and ART modification after LLV (aOR 1.6; 95% CI 1.0-2.4). The following factors were negatively associated with undetectable VL at 12 months: higher VL during LLV (aOR 0.57 per log10 copies/mL; 95% CI 0.37-0.89), injecting drug use (aOR 0.67; 95% CI 0.47-0.96), and regimens with protease inhibitors (aOR 0.65; 95% CI 0.49-0.87) or combined anchor drugs (aOR 0.52; 95% CI 0.32-0.85). CONCLUSION: Most people with LLV did not experience sustained viral suppression during 24-month follow-up, supporting the association between LLV and inferior treatment outcome.

Investigating rates and predictors of viral blips, low-level viraemia and virological failure in the Australian HIV observational database.

OBJECTIVES: Australia has made significant progress towards achieving the UNAIDS's 95-95-95 cascade targets including HIV viral suppression. To investigate the burden of HIV viraemia, we assessed viral blips, low-level viraemia (LLV) and virologic failure (VF) in an Australian cohort. METHODS: We studied the proportion of people with viral suppression, viral blips, LLV and VF in the Australian HIV observational database (AHOD) between 2010 and 2021. The association between blips or LLV, and VF was investigated using Cox regression, and predictors of viral blips and LLV were assessed using repeated-measured logistic regression. RESULTS: Among 2544 AHOD participants who were in follow-up and on antiretroviral therapy (ART) from 1 January 2010 (88.7% male), 444 had experienced VF (incidence rate: 2.45 [95% CI: 2.23-2.69] per 100 person-years [PY]) during 18,125 PY of follow-up (a median of 7.6 years). The proportion of people with VF decreased over time, whereas rates of blips and LLV remained stable. Participants with blips (hazard ratio, 2.89; 95% CI: 2.31-3.61) and LLV (4.46; 95% CI: 3.38-5.89) were at increased risk of VF. Hepatitis B co-infection, longer documented treatment interruption duration, younger age and lower CD4 at ART initiation, and protease inhibitors-based initial regimen were associated with an increased risk of VF. Common predictors of blips and LLV such as higher HIV-1 RNA and lower CD4 at ART initiation, longer treatment interruption, more VL testing and types of care settings (hospitals vs. sexual health services) were identified. CONCLUSIONS: Blips and LLV predict subsequent VF development. We identified important predictors of HIV viraemia including VF among individuals on INSTI-based regimens to help direct HIV management plans.

Genetic diversity in the partial sequence of the HIV-1 gag gene among people living with multidrug-resistant HIV-1 infection

ABSTRACT The group-specific antigen (gag) plays a crucial role in the assembly, release, and maturation of HIV. This study aimed to analyze the partial sequence of the HIV gag gene to classify HIV subtypes, identify recombination sites, and detect protease inhibitor (PI) resistance-associated mutations (RAMs). The cohort included 100 people living with HIV (PLH) who had experienced antiretroviral treatment failure with reverse transcriptase/protease inhibitors. Proviral HIV-DNA was successfully sequenced in 96 out of 100 samples for gag regions, specifically matrix (p17) and capsid (p24). Moreover, from these 96 sequences, 82 (85.42%) were classified as subtype B, six (6.25%) as subtype F1, one (1.04%) as subtype C, and seven (7.29%) exhibited a mosaic pattern between subtypes B and F1 (B/F1), with breakpoints at p24 protein. Insertions and deletions of amino acid at p17 were observed in 51 samples (53.13%). The prevalence of PI RAM in the partial gag gene was observed in 78 out of 96 PLH (81.25%). Among these cases, the most common mutations were R76K (53.13%), Y79F (31.25%), and H219Q (14.58%) at non-cleavage sites, as well as V128I (10.42%) and Y132F (11.46%) at cleavage sites. While B/F1 recombination was identified in the p24, the p17 coding region showed higher diversity, where insertions, deletions, and PI RAM, were observed at high prevalence. In PLH with virological failure, the analysis of the partial gag gene could contribute to more accurate predictions in genotypic resistance to PIs. This can aid guide more effective HIV treatment strategies.