HIV-1 Drug Resistance Mutations Research Articles

Resistance Mutation Patterns among HIV-1-Infected Children and Features of the Program for Prevention of Mother-to-Child Transmission in Vietnam’s Central Highlands and Southern Regions, 2017–2021

The Vietnam Ministry of Health (MOH) has intensified efforts in its aim to eliminate AIDS by 2030. Expanding the program for prevention of mother-to-child transmission (PMTCT) is a significant step towards achieving this goal. However, there are still HIV-exposed children who do not have access to PMTCT services, and some who have participated in the program but still contracted HIV. This study focused on assessing the prevalence and profile of HIV mutations among children under 18 months of age who had recently tested positive for HIV, while gaining insights into the implementation of early infant diagnostic (EID) tests. Between 2017 and 2021, 3.43% of 5854 collected dry blood spot (DBS) specimens from Vietnam’s Central and Southern regions showed positive EID results. This study identified a high prevalence of resistance mutations in children, totaling 62.9% (95% CI: 53.5–72.3). The highest prevalence of mutations was observed for NNRTIs, with 57.1% (95% CI: 47.5–66.8). Common mutations included Y181C and K103N (NNRTI resistance), M184I/V (NRTI resistance), and no major mutations for PI. The percentage of children with any resistance mutation was significantly higher among those who received PMTCT interventions (69.2%; 95% CI: 50.5–92.6%) compared with those without PMTCT (45.0%; 95% CI: 26.7–71.1%) with χ2 = 6.06, p = 0.0138, and OR = 2.75 (95% CI: 1.13–6.74). Mutation profiles revealed that polymorphic mutations could be present regardless of whether PMTCT interventions were implemented or not. However, non-polymorphic drug resistance mutations were predominantly observed in children who received PMTCT measures. Regarding PMTCT program characteristics, this study highlights the issue of late access to HIV testing for both mothers and their infected children. Statistical differences were observed between PMTCT and non-PMTCT children. The proportion of late detection of HIV infection and breastfeeding rates were significantly higher among non-PMTCT children (p < 0.05). Comparative analysis between children with low viral load (≤200 copies/mL) and high viral load (>200 copies/mL) showed significant differences between the mothers’ current ART regimens (p = 0.029) and the ARV prophylaxis regimen for children (p = 0.016). These findings emphasize the need for comprehensive surveillance to assess the effectiveness of the PMTCT program, including potential transmission of HIV drug-resistance mutations from mothers to children in Vietnam.

Applying Next-Generation Sequencing to Track HIV-1 Drug Resistance Mutations Circulating in Portugal.

The global scale-up of antiretroviral treatment (ART) offers significant health benefits by suppressing HIV-1 replication and increasing CD4 cell counts. However, incomplete viral suppression poses a potential threat for the emergence of drug resistance mutations (DRMs), limiting ART options, and increasing HIV transmission. We investigated the patterns of transmitted drug resistance (TDR) and acquired drug resistance (ADR) among HIV-1 patients in Portugal. Data were obtained from 1050 HIV-1 patient samples submitted for HIV drug resistance (HIVDR) testing from January 2022 to June 2023. Evaluation of DRM affecting viral susceptibility to nucleoside/tide reverse transcriptase inhibitors (NRTIs), non-nucleoside reverse transcriptase inhibitors (NNRTIs), protease inhibitors (PIs), and integrase strand transfer inhibitors (INSTIs) was performed using an NGS technology, the Vela Diagnostics Sentosa SQ HIV-1 Genotyping Assay. About 71% of patients were ART naïve and 29% were experienced. Overall, 20% presented with any DRM. The prevalence of TDR and ADR was 12.6% and 41.1%, respectively. M184V, T215S, and M41L mutations for NRTI, K103N for NNRTI, and M46I/L for PIs were frequent in naïve and treated patients. E138K and R263K mutations against INSTIs were more frequent in naïve than treated patients. TDR and ADR to INSTIs were 0.3% and 7%, respectively. Patients aged 50 or over (OR: 1.81, p = 0.015), originating from Portuguese-speaking African countries (PALOPs) (OR: 1.55, p = 0.050), HIV-1 subtype G (OR: 1.78, p = 0.010), and with CD4 < 200 cells/mm3 (OR: 1.70, p = 0.043) were more likely to present with DRMs, while the males (OR: 0.63, p = 0.003) with a viral load between 4.1 to 5.0 Log10 (OR: 0.55, p = 0.003) or greater than 5.0 Log10 (OR: 0.52, p < 0.001), had lower chances of presenting with DRMs. We present the first evidence on TDR and ADR to INSTI regimens in followed up patients presenting for healthcare in Portugal. We observed low levels of TDR to INSTIs among ART-naïve and moderate levels in ART-exposed patients. Regimens containing PIs could be an alternative second line in patients with intermediate or high-level drug resistance, especially against second-generation INSTIs (dolutegravir, bictegravir, and cabotegravir).

A validated in-house assay for HIV drug resistance mutation surveillance from dried blood spot specimens

Despite increasing scale-up of antiretroviral therapy (ART) coverage, challenges related to adherence and HIV drug resistance (HIVDR) remain. The high cost of HIVDR surveillance is a persistent challenge with implementation in resource-constrained settings. Dried blood spot (DBS) specimens have been demonstrated to be a feasible alternative to plasma or serum for HIVDR genotyping and are more suitable for lower resource settings. There is a need for affordable HIVDR genotyping assays which can amplify HIV-1 sequences from DBS specimens, particularly those with low viral loads, at a low cost. Here, we present an in-house assay capable of reliably amplifying HIV-1 protease and partial reverse transcriptase genes from DBS specimens, which covers the complete World Health Organization 2009 list of drug resistance mutations under surveillance. DBS specimens were prepared using whole blood spiked with HIV-1 at concentrations of 10,000, 5000, 1000, and 500 copies/mL (n=30 for each concentration). Specimens were tested in triplicate. A two-step approach was used consisting of cDNA synthesis followed by nested PCR. The limit of detection of the assay was calculated to be approximately 5000 (95% CI: 3200–10,700) copies/mL for the protease gene and 3600 (95% CI: 2200–10,000) copies/mL for reverse transcriptase. The assay was observed to be most sensitive with higher viral load specimens (97.8% [95% CI: 92.2–99.7]) for both protease and reverse transcriptase at 10,000 copies/mL with performance decreasing with the use of specimens with lower viral loads (46.7% [36.1–57.5] and 60.0% [49.1–70.2] at 500 copies/mL for protease and reverse transcriptase, respectively). Ultimately, this assay presents a promising opportunity for use in resource-constrained settings. Future work should involve validation under field conditions including sub-optimal storage conditions and preparation of DBS with fingerprick blood in order to accurately reflect real-world collection scenarios.

Prevalence of HIV Drug Resistance Mutations among Treatment-Naive People Living with HIV in a Tertiary Care Center in India.

India has the third-largest number of people living with HIV (PLHIV) in the world. A national program provides free access to standard uniform antiretroviral therapy. However, the program is not monitored by comprehensive drug resistance surveys. The aim of this study was to determine the prevalence of HIV drug resistance mutations (DRMs) among treatment-naive PLHIV in a large antiretroviral treatment center of the national program. This cross-sectional study was done in 2017 and involved 200 consecutive treatment-naive PLHIV. A target fragment of 1,306 bp in the reverse transcriptase and protease regions was amplified. Identification of mutations and drug resistance interpretation was done by HIV Genotypic Resistance Interpretation and International Antiviral Society-USA list. Sequencing was successful in 177 samples. The majority (98.8%; 175/177) belonged to subtype C. Nineteen of 177 patients (10.7%; 95% CI: 6.2%-15.3%) had at least one major DRM. The prevalence of non-nucleoside reverse transcriptase inhibitor (NNRTI) mutations was 10.2% (18/177). The most frequent mutations were E138A/K, A98G, K103N, V179D, and K101H/E. The prevalence of nucleoside reverse transcriptase inhibitor (NRTI) mutations was 1.1% (2/177). None of the samples had major protease inhibitor resistance mutations. The prevalence of NNRTI mutations in this study was >10%, crossing the threshold recommended by the WHO to change the NNRTI-based first-line regimen to non-NNRTI based. In 2021, the national program replaced efavirenz with dolutegravir in the first-line regimen of tenofovir, lamivudine, and efavirenz. As the majority (64%) of PLHIV in India are accessing free ART from the national program, this study highlights the need for regular nationally representative drug resistance surveys for optimizing antiretroviral regimens in the program.

Emergence of HIV-1 Drug Resistance Mutations Among Children and Adolescents Undergoing Prolonged Antiretroviral Therapy in Guangxi

Antiretroviral therapy (ART) has been implemented in Guangxi for a long time, and no reports about HIV drug resistance mutation (DRM) among children and adolescents experiencing virological failure after ART. This study aimed to analyze HIV DRM prevalence, patterns, and influencing factors among children and adolescents experiencing virologic failure after ART in Guangxi. We collected samples from a total of 491 HIV-infected individuals under 18 years old experiencing virological failure after ART from 14 cities in Guangxi. Sequencing and DRM analysis were performed based on pol region. Multivariate logistic regression was employed to analysis the influencing factors of DRM. Among these patients, 396 cases were successfully sequenced. Of all, 52.53% exhibited HIV DRM, including NNRTI (48.48%), NRTI (34.85%) and PI (1.01%). NRTI and NNRTI dual-class resistance was prevalent (30.3%). M184V/I and K103N mutations were the common mutations in NRTI and NNRTI respectively. Men gender (aOR=2.1, 95%CI: 1.26-3.50), CRF01_AE subtype (OR=2.50, 95%CI: 1.02-5.88), the primary regimen 3TC+AZT+NVP (OR=10.00, 95%CI: 5.00-25.00), low pre-treatment CD4+ T lymphocytes (<200 cells/mm³) (OR=1.85, 95%CI: 1.00-3.45), and high viral load (> 1000 copies/ml) (OR=4.90, 95%CI: 1.03-23.39) shown higher risk of DRM. HIV DRM is pervasive among children and adolescents experiencing virologic failure in Guangxi. Timely HIV DRM monitoring is crucial to mitigate major mutation accumulation and inform effective treatment strategies.

HIV protease resistance mutations in patients receiving second-line antiretroviral therapy in Libreville, Gabon

IntroductionIn 2022, the WHO reported that 29.8 million people around the world were living with HIV (PLHIV) and receiving antiretroviral treatment (ART), including 25‌ 375 people in Gabon (54% of all those living with HIV in the country). The literature reports a frequency of therapeutic failure with first-line antiretrovirals (ARVs) of between 20% and 82%. Unfortunately, data relating to the failure of second-line ARVs are scarce in Gabon. This study aims to determine the profiles of HIV drug resistance mutations related to protease inhibitors in Gabon.MethodologyPlasma from 84 PLHIV receiving ARVs was collected from 2019 to 2021, followed by RNA extraction, amplification, and sequencing of the protease gene. ARV resistance profiles were generated using the Stanford interpretation algorithm version 8.9-1 (https://hivdb.stanford.edu) and statistical analyses were performed using EpiInfo software version 7.2.1.0 (CDC, USA).ResultsOf 84 HIV plasma samples collected from 45 men and 39 women, 342 mutations were detected. Of these, 43.3% (148/342) were associated with nucleoside reverse transcriptase inhibitors (NRTIs), 30.4% (104/342) with non-nucleoside reverse transcriptase inhibitors (NNRTIs), and 26.3% (90/342) with protease inhibitors (PIs). Most NRTI mutations were associated with thymidine analogues (TAMs) (50.7%; 75/148), including T215F/V (14.9%; 22/148), D67DN/E/G/N/T (10.1%; 15/148), M41L (9.5%; 14/148), and K70E/KN/S/R (9.5%; 14/148). Resistance mutations related to non-TAM NRTIs (33.1%; 49/148) were M184V (29.1%; 43/148), and L74I/V (8.1%; 12/148). NNRTI mutations were predominantly K103N/S (32.7%; 34/104), V108I (10.6%; 11/104), A98G (10.6%; 11/104), and P225H (9.6%; 10/104). Minor mutations associated with PIs (60.0%; 54/90) were predominantly K20I (15.6%; 14/90) and L10F/I/V (14.5%; 13/90). The major mutations associated with PIs (40.0%; 36/90) were M41L (12.2%; 11/90), I84V (6.7%; 06/90), and V82A (6.7%; 06/90). The four most prescribed therapeutic regimens were TDF + 3TC + LPV/r (20.3%; 17/84), ABC + DDI + LPV/r (17.9%; 15/84), TDF + FTC + LPV/r (11.9%; 10/84), and ABC + 3TC + LPV/r (11.9%; 10/84).ConclusionThis study revealed that HIV drug resistance mutations are common in Gabon. The major mutations associated with PIs were M41L, I84V, and V82A. There is a need for access to new NRTIs, NNRTIs, and PIs for a better therapeutic management of PLHIV in Gabon.

Impact Of Low-Frequency HIV-1 Drug Resistance Mutations On Antiretroviral Therapy Outcomes.

The association between low-frequency HIV-1 drug resistance mutations (DRMs) and treatment failure (TF) is controversial. We explore this association using NGS methods that accurately sample low-frequency DRMs. We enrolled women with HIV-1 in Malawi who were either ART naïve (A), had ART failure (B), or had discontinued ART (C). At entry, A and C began an NNRTI-based regimen and B started a PI-based regimen. We used Primer ID MiSeq to identify regimen-relevant DRMs in entry and TF plasma samples, and a Cox proportional hazards model to calculate hazard ratios (HRs) for entry DRMs. Low-frequency DRMs were defined as ≤ 20%. We sequenced 360 participants. Cohort B and C participants were more likely to have TF than Cohort A participants. The presence of K103N at entry significantly increased TF risk among A and C participants at both high and low frequency, with HR of 3.12 [1.58-6.18, 95% CI] and 2.38 [1.00-5.67, 95% CI] respectively. At TF, 45% of participants showed selection of DRMs while in the remaining participants there was an apparent lack of selective pressure from ART. Using accurate NGS for DRM detection may benefit an additional 10% of the patients by identifying low-frequency K103N mutations.

High prevalence of pre-treatment and acquired HIV-1 drug resistance mutations among non-citizens living with HIV in Botswana.

Approximately 30,000 non-citizens are living with HIV in Botswana, all of whom as of 2020 are eligible to receive free antiretroviral treatment (ART) within the country. We assessed the prevalence of HIV-1 mutational profiles [pre-treatment drug resistance (PDR) and acquired drug resistance (ADR)] among treatment-experienced (TE) and treatment-naïve (TN) non-citizens living with HIV in Botswana. A total of 152 non-citizens living with HIV were enrolled from a migrant HIV clinic at Independence Surgery, a private practice in Botswana from 2019-2021. Viral RNA isolated from plasma samples were genotyped for HIV drug resistance (HIVDR) using Sanger sequencing. Major known HIV drug resistance mutations (DRMs) in the pol region were determined using the Stanford HIV Drug Resistance Database. The proportions of HIV DRMs amongst TE and TN non-citizens were estimated with 95% confidence intervals (95% CI) and compared between the two groups. A total of 60/152 (39.5%) participants had a detectable viral load (VL) >40 copies/mL and these were included in the subsequent analyses. The median age at enrollment was 43 years (Q1, Q3: 38-48). Among individuals with VL > 40 copies/mL, 60% (36/60) were treatment-experienced with 53% (19/36) of them on Atripla. Genotyping had a 62% (37/60) success rate - 24 were TE, and 13 were TN. A total of 29 participants (78.4, 95% CI: 0.12-0.35) had major HIV DRMs, including at least one non-nucleoside reverse transcriptase inhibitor (NNRTI) associated DRM. In TE individuals, ADR to any antiretroviral drug was 83.3% (20/24), while for PDR was 69.2% (9/13). The most frequent DRMs were nucleoside reverse transcriptase inhibitors (NRTIs) M184V (62.1%, 18/29), NNRTIs V106M (41.4%, 12/29), and K103N (34.4%, 10/29). No integrase strand transfer inhibitor-associated DRMs were reported. We report high rates of PDR and ADR in ART-experienced and ART-naïve non-citizens, respectively, in Botswana. Given the uncertainty of time of HIV acquisition and treatment adherence levels in this population, routine HIV-1C VL monitoring coupled with HIVDR genotyping is crucial for long-term ART success.

Pretreatment and Acquired Drug Resistance in Children With Human Immunodeficiency Virus Type 1 in Jos, Nigeria.

We determined pretreatment and acquired human immunodeficiency virus (HIV) drug resistance among children with HIV type 1 (HIV-1) in Jos, Nigeria. The majority (71%) of those who failed first-line antiretroviral therapy were on a nevirapine-containing regimen. The prevalence of pretreatment (48%) and acquired (76%) HIV drug resistance mutations was high in our study. Wider access to HIV drug resistance testing after treatment failure is necessary to optimize second-line treatment options among children with HIV in Nigeria.

Virologic Nonsuppression and HIV Drug Resistance Among People Who Inject Drugs and Their Sexual and Injecting Partners in Kenya.

We evaluated the prevalence and correlates of HIV viral nonsuppression and HIV drug resistance (HIV-DR) in a cohort of people who inject drugs living with HIV (PWID-LH) and their sexual and injecting partners living with HIV in Kenya. HIV-DR testing was performed on participants with viral nonsuppression. Of 859 PWID-LH and their partners, 623 (72.5%) were on antiretroviral therapy (ART) ≥4 months and 148/623 (23.8%) were not virally suppressed. Viral nonsuppression was more common among younger participants and those on ART for a shorter duration. Among 122/148 (82.4%) successfully sequenced samples, 55 (45.1%) had detectable major HIV-DR mutations, mainly to non-nucleoside and nucleotide reverse transcriptase inhibitors (NNRTI and NRTI). High levels of HIV-DR among those with viral nonsuppression suggests need for viral load monitoring, adherence counseling, and timely switching to alternate ART regimens in this key population.

Human immunodeficiency virus-1 Drug Resistance Mutations in Iranian Treatment-experienced Individuals.

Human immunodeficiency virus-1 infection still remains a global health threat. While antiretroviral therapy is the primary treatment option, concerns about the emergence of drug-resistance mutations and treatment failure in HIV-infected patients persist. In this study, we investigated the development of drug resistance in HIV-1-infected individuals receiving antiretroviral therapy for 6-10 years. In this cross-sectional study, we evaluated 144 people living with HIV-1 who had received antiretroviral therapy for at least 6 years. Plasma specimens were collected, and HIV-1 viral load and drug-resistance mutations were assessed using molecular techniques. The demographic and epidemiological characteristics of the participants were also analyzed: Twelve [8.3%) of the studied patients showed a viral load over 1000 copies per/mL, which indicates the suboptimal response to antiretroviral therapy. Significant correlations were found between viral load and CD4 count, as well as epidemiological factors, such as vertical transmission, history of imprisonment, and needle stick injuries. Drug resistance mutations were detected in 10 (83.3%) of patients who failed on antiretroviral therapy, with the most common mutations observed against nucleoside reverse transcriptase inhibitors (5 (41.7%)) and non-nucleoside reverse transcriptase inhibitors (9 (75%)). Phylogenetic analysis revealed that 12 patients who failed treatment were infected with CRF35_AD. Our study provides important insights into the characteristics and development of drug resistance in HIV-1-infected individuals receiving long-term antiretroviral therapy in Iran. The findings underline the need for regular viral load monitoring, individualized treatment selection, and targeted interventions to optimize treatment outcomes and prevent the further spread of drug-resistant strains.

Alarming Rise of Primary HIV Drug Resistance in Major Regions of Russia.

The study aimed to compare the prevalence of surveillance HIV drug resistance mutations (SDRMs) across the main federal districts of Russia. A pooled analysis was conducted to examine data on HIV primary drug resistance (HIV PrimDR). The analysis was based on published results primarily from Russian regional clinical and scientific laboratories, covering a span of 20 years. The findings indicate that three surveyed regions, namely Central, Far Eastern, and Volga, exhibit a low level of HIV PrimDR prevalence (not exceeding 5%), and this prevalence does not show a tendency to increase. In contrast, three major regions, namely Northwestern, Southern, and Siberian, demonstrate a significant and progressive increase in HIV PrimDR prevalence, with recent values surpassing 10%. Consequently, it was concluded that a change in the HIV treatment strategy in these regions is imperative, emphasizing the need to expedite the transition to the utilization of secondgeneration integrase inhibitors.

Characterization of HIV-1 subtypes and drug resistance mutations in Slovakia: update 2017-2018.

This study aimed to provide an overview on the HIV-1 subtypes circulating in Slovakia between 2017 and 2018 and to evaluate the risk of transmission of HIV‑resistant strains. The HIV epidemic in Slovakia is characterised by low incidence of new and pre-existing infections and aslightly elevated level of strain heterogeneity. Partial HIV pol gene sequences of 110 individuals newly diagnosed with HIV between 2017 and 2018 were analysed. The genotypic analysis revealed sporadic occurrence of mutations linked to HIV resistance to antiretroviral therapy (ART). The HIV-1 Bsubtype has been found as predominant (84.55%) and primarily linked to men who have sex with men (MSM). Atotal of eighteen individuals (15.45%) were found to be infected with HIV-1 non-B subtypes. The data suggest aminimal risk of aresistant HIV strain transmission and amarginal rise of HIV-1 subtypes´ diversity. The HIV-1 Bsubtype remains the most prevalent in the period 2017-2018 in Slovakia (Tab. 2, Fig. 2, Ref. 37).

HIV drug resistance among patients experiencing antiretroviral therapy failure in Russia, 2019–2021

Increasing HIV drug resistance is an important public health concern. The current study aimed to assess HIV drug resistance among people who live with HIV (PLWH) experiencing virological failure.Blood samples and epidemiological characteristics were collected in four Siberian regions from PLWH experiencing ART failure. Partial pol gene sequences were obtained for the study individuals. Drug resistance mutations (DRMs) were predicted using the Stanford HIVdb Program. The association of HIV DRM with epidemiological characteristics was estimated using logistic regression analysis. Further analysis was performed for children (0–14 y old) and adults (≥15 y old) separately.In total, 815 (89.4%) patients were included in the final dataset. Overall, 501 (61.5%) patients had DRM detected. NRTI DRM was more common in children, while NRTI+NNRTI DRM was more frequent in adults (P < 0.001). Krasnoyarsk region, male sex and high viral load were positively associated with the presence of DRM in adults, while higher CD4 cell count and PI/INSTI-based ART had a negative association. No association between epidemiological characteristics and DRM was identified in children. The remaining 38.5% of patients with virological failure had no DRM detected; those patients were likely to have insufficient ART adherence. Most (55.5%) patients had HIV CRF63_02A6, followed by sub-subtype A6 (39.2%).This study revealed poor ART adherence as a main factor driving ART failure among PLWH in the Siberian region. DRM was detected in over 60% of PLWH experiencing ART failure. The current results highlight an urgent need for the introduction of special programs focusing on ART adherence improvement.

Temporal trends and transmission dynamics of pre-treatment HIV-1 drug resistance within and between risk groups in Kenya, 1986-2020.

Evidence on the distribution of pre-treatment HIV-1 drug resistance (HIVDR) among risk groups is limited in Africa. We assessed the prevalence, trends and transmission dynamics of pre-treatment HIVDR within and between MSM, people who inject drugs (PWID), female sex workers (FSWs), heterosexuals (HETs) and perinatally infected children in Kenya. HIV-1 partial pol sequences from antiretroviral-naive individuals collected from multiple sources between 1986 and 2020 were used. Pre-treatment reverse transcriptase inhibitor (RTI), PI and integrase inhibitor (INSTI) mutations were assessed using the Stanford HIVDR database. Phylogenetic methods were used to determine and date transmission clusters. Of 3567 sequences analysed, 550 (15.4%, 95% CI: 14.2-16.6) had at least one pre-treatment HIVDR mutation, which was most prevalent amongst children (41.3%), followed by PWID (31.0%), MSM (19.9%), FSWs (15.1%) and HETs (13.9%). Overall, pre-treatment HIVDR increased consistently, from 6.9% (before 2005) to 24.2% (2016-20). Among HETs, pre-treatment HIVDR increased from 6.6% (before 2005) to 20.2% (2011-15), but dropped to 6.5% (2016-20). Additionally, 32 clusters with shared pre-treatment HIVDR mutations were identified. The majority of clusters had R0 ≥ 1.0, indicating ongoing transmissions. The largest was a K103N cluster involving 16 MSM sequences sampled between 2010 and 2017, with an estimated time to the most recent common ancestor (tMRCA) of 2005 [95% higher posterior density (HPD), 2000-08], indicating propagation over 12 years. Compared to HETs, children and key populations had higher levels of pre-treatment HIVDR. Introduction of INSTIs after 2017 may have abrogated the increase in pre-treatment RTI mutations, albeit in the HET population only. Taken together, our findings underscore the need for targeted efforts towards equitable access to ART for children and key populations in Kenya.

High viral suppression and detection of dolutegravir-resistance associated mutations in treatment-experienced Tanzanian adults living with HIV-1 in Dar es Salaam

To curb HIV infection rate in Tanzania, antiretroviral therapy (ART) has been scaled up since 2006, and in 2019, the country shifted to regimen including dolutegravir as a default first line. We assessed the success of ART and the contribution of HIV drug resistance (HIVDR) to unsuppressed viral loads. Between February and May 2023 a cross-sectional survey with random sampling was conducted in the six clinics in an urban cohort in Dar es Salaam. Patients with unsuppresed viral loads (local criteria viral load (VL) ≥ 1000 copies/mL) were tested for HIVDR mutations using the WHO adapted protocol for plasma samples. Mutations were interpreted using the Stanford HIVDR database. In total 600 individuals participated in this survey, the majority were female (76.83%), mean age (pm standard deviation) was 44.0 (pm 11.6) years. The median duration on ART (interquartile range) was 6.5 (3.9–10.2) years. Approximately 99% were receiving tenofovir + lamivudine + dolutegravir as a fixed dose combination. VL testing was successful in 99.67% (598/600) of survey patients and only 33 had VL ≥ 1000 copies/mL, resulting in a viral suppression level of 94.48% (565/598, 95% CI 92.34–96.17%). For 23 samples, protease and reverse transcriptase (RT) genotyping were successful, with 13 sequences containing RT inhibitor surveillance drug resistance mutations (SDRMs) (56.5%). No SDRM against protease inhibitors were detected. Thirty samples were successfully genotyped for integrase with 3 sequences (10.08%) containing integrase strand transfer inhibitor (INSTI) SDRMs. In samples successfully genotyped in the three genetic regions, 68.18% (16/22) had a genotypic susceptibility score (GSS) ≥ 2.5 for the concurrent regimen, implying factors beyond drug resistance caused the unsuppressed viral load. For five patients, GSS indicated that HIVDR may have caused the unsuppressed viral load. All three patients with INSTI resistance mutations were highly resistant to dolutegravir and accumulated nucleoside and non-nucleoside RT inhibitor HIVDR mutations. Although in this cohort the last 95 UNAIDS target was almost achieved, HIVDR mutations, including INSTIs resistance mutations were detected in HIV-positive individuals taking ART for at least one year. We recommend the design and implementation of high-impact interventions to prevent the increase of HIVDR, failure of dolutegravir and address the non-resistance factors in the study area.

Performance characteristics of Allele-Specific PCR (ASPCR) in detecting drug resistance mutations among non-B HIV-1 Variants

Allele-Specific Polymerase Chain Reaction (ASPCR) is an affordable point-mutation assay whose validation could improve the detection of HIV-1 drug resistance mutations (DRMs) in resource-limited settings (RLS). We assessed the performance of ASPCR onforty-four non-B HIV-1 plasma samples from patients who were ARV treated in failure in N’Djamena-Chad. Viral RNA was reverse-transcribed and amplified using LightCycler® FastStart DNA MasterPLUS SYBR Green I. Detection of six major DRMs (K70R, K103N, Y181C, M184V, T215F, T215Y) was evaluated on Roche LightCycler®480 automated system (with dilutions 0.01–100%). ASPCR-results were compared to Sanger-sequencing (gold-standard). Correlations of mutation curves were excellent (R2 >0.97); all DRMs were detected with desirable mutant/wild-type threshold differences (ΔCt≥9) except K70R(ΔCtK70R=6; ΔCtK103N=13; ΔCtM184V=9; ΔCtT215F=12; ΔCtT215Y=12; ΔCtY181C=9) and positive controls were below required thresholds. Also, ASPCR reproducibility on DRMs was assessed by using dilutions of intra-assay and inter-assay coefficient of variations respectively with a threshold of less than 50(i.e.<0.50 variation) which are;: K70R (0.02–0.28 vs. 0.12–0.37), K103N (0.08–0.42 vs. 0.12–0.37), Y181C (0.12–0.39 vs. 0.31–0.37), M184V (0.13–0.39 vs. 0.23–0.42), T215F (0.05–0.43 vs. 0.04–0.45) and T215Y (0.13–0.41 vs. 0.19–0.41). DRM detection-rate by ASPCR vs Sanger was respectively: M184V (63.6% vs. 38.6%); T215F (18.1% vs. 9.1%); T215Y (6.8% vs. 2.3%); K70R (4.5% vs. 2.3%). K103N (22.7% vs. 13.6%); Y181C (13.6% vs. 11.4%). Correlations of mutation curves were excellent (R2 >0.97); all DRMs were detected with desirable mutant/wild-type threshold differences (ΔCt≥9) except K70R(ΔCtK70R=6; ΔCtK103N=13; ΔCtM184V=9; ΔCtT215F=12; ΔCtT215Y=12; ΔCtY181C=9) and positive controls were below required thresholds. Also, ASPCR reproducibility on DRMs was assessed by using dilutions of intra-assay and inter-assay coefficient of variations respectively with a threshold of less than 50(i.e.<0.50 variation) which are;: K70R (0.02–0.28 vs. 0.12–0.37), K103N (0.08–0.42 vs. 0.12–0.37), Y181C (0.12–0.39 vs. 0.31–0.37), M184V (0.13–0.39 vs. 0.23–0.42), T215F (0.05–0.43 vs. 0.04–0.45) and T215Y (0.13–0.41 vs. 0.19–0.41). DRM detection-rate by ASPCR vs Sanger was respectively: M184V (63.6% vs. 38.6%); T215F (18.1% vs. 9.1%); T215Y (6.8% vs. 2.3%); K70R (4.5% vs. 2.3%). K103N (22.7% vs. 13.6%); Y181C (13.6% vs. 11.4%). ASPCR appears more efficient for detecting DRMs on diverse HIV-1 non-B circulating in RLS like Chad.

Prevalence of HIV drug resistance among adolescents receiving ART in Cameroon with low- or high-level viraemia.

To characterize HIV drug resistance (HIVDR) below and above the WHO threshold of 1000 copies/mL, considered for the definition of HIV ART failure in resource-limited settings. From a cohort of 280 adolescents (aged 10-19 years) receiving ART for at least 6 months, genotypic resistance testing (GRT) was attempted for two groups of participants: participants with low-level viraemia [LLV; viral load (VL) 200-999 copies/mL] and those in virological failure (VF; confirmed VL ≥1000 copies/mL) using an in-house method. The Stanford HIValg Program was used to identify relevant HIVDR mutations and predict the efficacy of the newly introduced tenofovir-lamivudine-dolutegravir combination. GRT was successfully performed in 54/58 (93.1%) eligible participants, of which 28/31 (90.3%) were in VF and 26/27 (96.3%) had LLV. A high level of resistance was found both in adolescents with LLV and those in VF, with respectively 84.6% (22/26) and 75.0% (21/28) of participants harbouring at least one HIVDR mutation. NRTIs and NNRTIs were the most affected drug classes in both population groups. In contrast, PIs were not significantly affected and dolutegravir was expected to be active for all participants tested. However, for the newly introduced dolutegravir-based combination, functional monotherapy (dolutegravir only) was potentially possible for 22.7% (5/22) of the participants with LLV. Our findings show that the 1000 copies/mL threshold is not an indicator of virological success and we call for a revision of the current WHO definition of VF in resource-limited countries.

Characterisation of HIV-1 reservoirs in paediatric populations: protocol for a systematic review and meta-analysis

IntroductionThe success of antiretroviral therapy (ART) has changed HIV from a deadly to a chronic infection, thus increasing the transitioning from infancy toward adulthood. However, the virostatic nature of antiretrovirals...

HIV Drug Resistance Mutations and Subtype Profiles among Pregnant Women of Ho Chi Minh City, South Vietnam.

According to the latest data released by UNAIDS, the global number of people living with HIV (PLHIV) in 2021 was 38.4 million, with 1.5 million new HIV infections. In different countries, a significant proportion of these cases occur in the adult fertile population aged 15-49 years. According to UNAIDS, Vietnam had a national HIV prevalence of 0.3% of the total population at the end of 2019, with approximately 230,000 PLHIV. The most effective way to prevent mother-to-child transmission of HIV is ART to reduce maternal viral load. HIV-infected pregnant women should undergo monthly monitoring, especially before the expected date of delivery. The aim of our work was to analyze subtypic structure and drug-resistant variants of HIV in pregnant women in Ho Chi Minh City. The study material was blood plasma samples from HIV-infected pregnant women: 31 women showed virological failure of ART, and 30 women had not previously received therapy. HIV-1 genotyping and mutation detection were performed based on analysis of the nucleotide sequences of the pol gene region. More than 98% of sequences genotyped as HIV-1 sub-subtype CRF01_AE. When assessing the occurrence of drug resistance mutations, genetic resistance to any drug was detected in 74.41% (95% CI: 62.71-85.54%) of patients. These included resistance mutations to protease inhibitors in 60.66% (95% CI: 47.31-72.93%) of patients, to NRTIs in 8.20% (95% CI: 2.72-18.10%), and to NNRTIs in 44.26% (95% CI: 31.55-57.52%). Mutations associated with NRTI (2) and NNRTI (8) resistance as well as PI mutations (12), including minor ones, were identified. The high prevalence of drug resistance mutations found in this study among pregnant women, both in therapeutically naive individuals and in patients with virological failure of ART, indicates that currently used regimens in Vietnam are insufficient to prevent vertical HIV infection.