Disparity of HIV-1 Pretreatment Drug Resistance in Men Who Have Sex With Men and the Heterosexual Population in Guangxi, China

Background

The prevalence of human immunodeficiency type 1 (HIV-1) pretreatment drug resistance (PDR) in men who have sex with men (MSM) in Guangxi remains unclear, and its effect on antiretroviral therapy (ART) needs to be further studied.

Methods

Individuals newly diagnosed with HIV in Guangxi from 2016 to 2020, which mainly included MSM and the heterosexual (HES) population, were recruited in this study. Pol sequences were sequenced to analyze PDR and construct a genetic network. The risk factors for PDR and the effect on ART were respectively analyzed.

Results

The PDR of MSM in Guangxi was 4.7% (34/716), consisting of nonnucleoside reverse transcriptase inhibitors (3.5%), protease inhibitors (0.8%), integrase strand transfer inhibitors (0.7%), and nucleoside reverse transcriptase inhibitors (0.4%), and lower than that of HES (9.3% [77/827]). The subtype was associated with PDR, and MSM was lower than HES (CRF01_AE: 3.0% vs 8.0%; CRF07_BC: 4.1% vs 7.2%). CRF55_01B (adjusted odds ratio [aOR], 3.35) was a risk factor for PDR in MSM, while CRF08_BC (aOR, 2.34) and older (aOR, 2.75) were risk factors for PDR in HES. Six of 18 (33.3%) PDR of MSM in the network connected to each other, lower than that of HES (61.1% [22/36]). CRF55_01B (aOR, 5.69) was a risk factor for PDR transmission in MSM, while CRF08_BC (aOR, 4.08) was a risk factor in HES. Pretreatment CD4⁺ T-cell count, age, infection route, and subtype were associated with recovery of CD4⁺ count and suppression of viral load.

Conclusions

The prevalence of PDR was different between MSM and HES, which may be associated with subtype. Thus, the monitoring of subtype and PDR should be strengthened.

High prevalence of HIV-1 transmitted drug resistance and factors associated with time to virological failure and viral suppression in Taiwan

BACKGROUND

Integrase strand transfer inhibitor (InSTI)-based regimens have become the major first-line treatment for HIV-1-infected patients in Taiwan. Transmitted drug resistance (TDR) and several clinical characteristics are associated with time to virological failure or viral suppression; however, these have not been investigated in Taiwan.

OBJECTIVES

To determine the impact of several factors on treatment outcomes in HIV-1-infected patients in Taiwan.

METHODS

The cohort included 164 HIV-1 treatment-naive patients in Taiwan from 2018 to 2020. Blood specimens were collected to determine the genotypic drug resistance using the Stanford University HIV drug resistance database. Cox proportional hazards models were used to identify factors associated with time to virological failure or viral suppression.

RESULTS

The prevalence of TDR in Taiwan was 27.4% and an increasing trend was seen from 2018 to 2020. TDR mutations related to NNRTIs were the most prevalent (21%) while TDR to InSTIs remained at a relatively low level (1.3%). A baseline HIV-1 viral load of ≥100 000 copies/mL was associated with a shorter time to virological failure [multivariate hazard ratio (mHR) 7.84; P = 0.018] and longer time to viral suppression (mHR 0.46; P < 0.001). Time to viral suppression was shorter in patients receiving InSTI-based regimens (mHR 2.18; P = 0.006). Different InSTI-based regimens as initial treatment did not affect the treatment outcomes.

CONCLUSIONS

This study found an increasing trend of HIV-1 TDR prevalence from 2018 to 2020 in Taiwan. Baseline HIV-1 viral load and receiving InSTI-based regimens are important factors associated with time to virological failure or viral suppression.

Survey of Pretreatment HIV Drug Resistance and Genetic Transmission Network Analysis Among HIV Patients in a High Drug-Use Area of Southwest China

Background: Pretreatment drug resistance (PDR) poses an increasing threat to the success of antiretroviral treatment (ART) programs in China. We aimed to conduct a survey of PDR among HIV patients in an area in Southwest China with extensive drug trafficking.

Methods: Consecutive cross-sectional surveys were conducted in Liangshan Prefecture of Sichuan Province from 2009 to 2018 based on the WHO-recommended method. PDR was identified by testing pol region sequences with the Stanford HIVdb algorithm (version 7.0). PDR prevalence and related factors were assessed by multivariable logistic regression. The transmission of HIV drug resistance was analyzed using a genetic transmission network.

Results: HIV-1 pol genes from 1889 patients were successfully amplified. The distribution of HIV-1 genotypes was as follows: CRF07_BC (94.0%), CRF08_BC (2.3%), CRF01_AE (2.0%) and others (1.4%). Of the participants, 6.9% (95% CI: 4.1-8.1%) had pretreatment resistance to 12 antiretroviral drugs recommended by the WHO, and nucleoside reverse transcriptase inhibitor (NRTI), non-nucleoside reverse transcriptase inhibitor (NNRTI) and protease inhibitors (PI) resistance were identified among 1.4% (95% CI: 0.7-3.4%), 5.8% (95% CI: 1.2-8.7%) and 0.4% (95% CI: 0.1-3.0%) of the patients, respectively. In the multivariate logistic model, the prevalence of PDR was 1.52-fold higher among intravenous drug users (IDUs) than among patients infected by heterosexual transmission (95% CI: 1.07-2.38; P=0.049), and the prevalence of PDR among patients diagnosed from 2017-2018 was 2.03-fold higher than that among patients diagnosed from 2009-2016 (95% CI: 1.18-5.76; P=0.018). A total of 26 clusters containing PDR and a rapidly growing drug resistance-related cluster containing the E138Q and V179D mutations were identified by genetic transmission network analysis.

Conclusion: The results show a moderate overall level of PDR prevalence and rapidly growing drug resistance over time. Preventive intervention should be focused on controlling the HIV epidemic among drug users, and surveillance is urgently needed to monitor the trend of PDR.

Clinical Impact of Pretreatment Human Immunodeficiency Virus Drug Resistance in People Initiating Nonnucleoside Reverse Transcriptase Inhibitor-Containing Antiretroviral Therapy: A Systematic Review and Meta-analysis

Background

Increased access to antiretroviral therapy (ART) has resulted in rising levels of pretreatment human immunodeficiency virus drug resistance (PDR). This is the first systematic review and meta-analysis to assess the impact of PDR on treatment outcomes among people initiating nonnucleoside reverse transcriptase inhibitor (NNRTI)–based ART, including the combination of efavirenz (EFV), tenofovir (TDF), and lamivudine or emtricitabine (XTC).

Methods

We systematically reviewed studies and conference proceedings comparing treatment outcomes in populations initiating NNRTI-based ART with and without PDR. We conducted subgroup analyses by regimen: (1) NNRTIs + 2 nucleoside reverse transcriptase inhibitors (NRTIs), (2) EFV + 2 NRTIs, or (3) EFV/TDF/XTC; by population (children vs adults); and by definition of resistance (PDR vs NNRTI PDR).

Results

Among 6197 studies screened, 32 were analyzed (31 441 patients). We found that individuals with PDR initiating NNRTIs across all the subgroups had increased risk of virological failure compared to those without PDR. Risk of acquisition of new resistance mutations and ART switch was also higher in people with PDR.

Conclusions

This review shows poorer treatment outcomes in the presence of PDR, supporting the World Health Organization’s recommendation to avoid using NNRTIs in countries where levels of PDR are high.

Outcome Impacts Due to Pathogen-Specific Antimicrobial Resistance: A Narrative Review of Published Literature

Antimicrobial resistance (AMR) has become a global threat to not only public health impacts but also clinical and economic outcomes. During the past decades, there have been many studies focusing on surveillance, mechanisms, and diagnostics of AMR in infectious diseases but the impacts on public health, clinical and economic outcomes due to emergence of these AMRs are rarely studied and reported. This review was aimed to summarize the findings from published studies to report the outcome impacts due to AMR of malaria, tuberculosis and HIV and briefly discuss the implications for application to other infectious diseases. PubMed/Medline and Google Scholar databases were used for search of empirical and peer-reviewed papers reporting public health, clinical and economic outcomes due to AMR of malaria, tuberculosis and HIV. Papers published through 1 December 2019 were included in this review. A total of 76 studies were included for this review, including 16, 49 and 11 on public health, clinical and economic outcomes, respectively. The synthesized data indicated that the emergence and spread of AMR of malaria, tuberculosis and HIV have resulted in adverse public health, clinical and economic outcomes. AMR of malaria, tuberculosis and HIV results in significant adverse impacts on public health, clinical and economic outcomes. Evidence from this review suggests the needs to consider the similar studies for other infectious diseases.

Trend of HIV transmitted drug resistance before and after implementation of HAART regimen restriction in the treatment of HIV-1 infected patients in southern Taiwan

Background

The use of fixed combination antiretroviral therapy with a low genetic barrier for the treatment of patients infected with human immunodeficiency virus (HIV) may affect the local HIV transmitted drug resistance (TDR) pattern. The present study aimed to investigate changes in the prevalence of HIV TDR following the implementation of a fixed regimen of HIV treatment in Taiwan in 2012.

Methods

TDR was measured in antiretroviral treatment-naïve HIV-1-infected individuals who participated in voluntary counseling and testing between 2007 and 2015 in southern Taiwan. Antiretroviral resistance mutations were interpreted using the HIVdb program from the Stanford University HIV Drug Resistance Database.

Results

Sequences were obtained from 377 consecutive individuals between 2007 and 2015. The overall prevalence rates of TDR HIV among the study population from 2007 to 2011 and 2012–2015 were 10.6 and 7.9%, respectively. Among the detected mutations, K103 N and V179D + K103R were more frequently observed after 2012. Four HIV-infected patients with K103 N variants were detected after 2012, and 4 of the 5 patients with V179D + K103R variants were found after 2012. No significant differences were observed in the TDRs among nucleoside reverse transcriptase inhibitors (NRTIs), non-NRTIs (NNRTIs), protease inhibitors, multiple drug resistance, and any drug resistance between period 1 (2007–2011) and period 2 (2012–2015).

Conclusions

A fixed treatment regimen with zidovudine/lamivudine + efavirenz or nevirapine as first-line therapy for treatment-naïve patients infected with HIV did not significantly increase the TDR during the 4-year follow-up period. Due to the increase in NNRTI resistance associated with mutations after 2012, a longer follow-up period and larger sample size are needed in future studies.

Patterns of emergent resistance-associated mutations after initiation of non-nucleoside reverse-transcriptase inhibitor-containing antiretroviral regimens in Taiwan: a multicenter cohort study

Background

Increasing trends of resistance-associated mutations (RAMs) to non-nucleoside reverse-transcriptase inhibitors (nNRTIs) have raised concerns about the effectiveness of the regimens in the national HIV treatment programs in resource-limited countries. We aimed to retrospectively investigate the incidence and patterns of emergent RAMs of HIV-1 in HIV-positive adults experiencing virological failure to first-line nNRTI-containing combination antiretroviral therapy (cART) in Taiwan.

Patients and methods

Between June 2012 and March 2016, 1138 antiretroviral-naïve HIV-positive adults without baseline RAMs who initiated nNRTI-containing regimens were included for analysis. Virological failure was defined as plasma viral load (PVL) ≥200 copies/mL after 6 months of cART or confirmed PVL ≥200 copies/mL after achieving PVL <50 copies/mL. Population sequencing was retrospectively performed to detect baseline and emergent RAMs. RAMs were interpreted using the International AIDS Society-USA 2016 mutations list.

Results

Seventy-one patients (6.2%) developed virological failure, which occurred in 14.8% (43/291), 3.9% (26/675), and 1.2% (2/172) of patients receiving 2 nucleoside reverse-transcriptase inhibitors (NRTIs) plus nevirapine, efavirenz, and rilpivirine, respectively. Among those, 53 (74.6%) had emergent RAMs identified, which included 43 (81.1%), 53 (100.0%), and 1 (1.9%) with RAMs to NRTIs, nNRTIs, and protease inhibitors, respectively; and 43 (81.1%) had multi-drug resistance. The most common emergent RAMs to NRTIs were M184V/I (42.3%) and K65R (28.2%), and those to nNRTIs were Y181C (42.3%), K103N (15.5%), G190A/E/Q (12.7%), V179D/E (12.7%), and V108I (9.9%).

Conclusion

While the rates of virological failure varied with the nNRTI used, the rate of emergent RAMs of HIV-1 to NRTIs and nNRTIs among the antiretroviral-naïve patients who failed nNRTI-containing cART remained low.

HIV-1 integrase strand-transfer inhibitor resistance in southern Taiwan

The use of antiretroviral therapy has reduced rates of mortality and morbidity in patients with human immunodeficiency virus/acquired immune deficiency syndrome(HIV/AIDS). However, transmission of drug-resistant strains poses a challenge to control the spread of HIV-1. Primary resistance to integrase strand-transfer inhibitors (INSTIs) is rare despite their increased use. The prevalence of transmitted drug resistance (TDR) to INSTIs was 0.9% in northern Taiwan. This study was to analyse the prevalence and risk factors of TDR to INSTIs in southern Taiwan. In this study, we enrolled antiretroviral treatment-naïve HIV-1-infected subjects who underwent voluntary counselling and testing from 2013 to 2016 in southern Taiwan. Genotypic drug resistance, coreceptor tropism (CRT) and INSTI resistance were determined. Logistic regression was used to analyse the risk factors for INSTI polymorphic substitution. Sequences were obtained from 184 consecutive individuals, of whom 96.7% were men who have sex with men and 3.3% were heterosexual. Of the patients, 10% (19/183) had hepatitis B and 33.3% (61/183) had syphilis infection. Subtype B HIV-1 strains were found in 96.1% of the patients. Fifteen patients (8.4%, 15/178) harboured nucleoside reverse transcriptase inhibitors, non-nucleoside reverse transcriptase inhibitors or protease inhibitors resistance. CCR-5 coreceptors were used by 71.4% (130/184) of the patients. None of the patients had INSTI resistance-associated mutations, however 16 patients had INSTI polymorphic substitutions, and they were associated with a higher HIV viral load (p = 0.03, OR 2.4, CI 1.1–5.3) and syphilis infection (p = 0.03, OR 3.7, CI 1.1–12.0). In conclusion, no signature INSTI resistance-associated mutations were detected in our cohort. Continued monitoring of TDR to INSTI is needed due to the increased use of INSTIs.

Pretreatment HIV drug resistance results in virological failure and accumulation of additional resistance mutations in Ugandan children

Background

Pretreatment HIV drug resistance (PDR) can impair virological response to ART, jeopardizing effective treatment for children.

Methods

Children aged ≤12 years initiated first-line ART in Uganda during 2010-11. Baseline and 6 monthly viral load (VL) and genotypic resistance testing if VL >1000 copies/mL was done. The 2015 IAS-USA mutation list and Stanford algorithm were used to score drug resistance mutations (DRMs) and susceptibility. Virological failure (VF) was defined as two consecutive VLs >1000 copies/mL or death after 6 months of ART. Factors associated with failure and acquired drug resistance (ADR) were assessed in a logistic regression analysis.

Results

Among 317 children enrolled, median age was 4.9 years and 91.5% received NNRTI-based regimens. PDR was detected in 47/278 (16.9%) children, of whom 22 (7.9%) had resistance against their first-line regimen and were therefore on a partially active regimen. After 24 months of follow-up, 92/287 (32.1%) had experienced VF. Children with PDR had a higher risk of VF (OR 15.25, P < 0.001) and ADR (OR 3.58, P = 0.01).

Conclusions

Almost one-third of children experienced VF within 24 months of NNRTI-based first-line treatment. PDR was the strongest predictor of VF and ADR, and therefore presents a major threat in children. There is a need for ART regimens that maximize effectiveness of first-line therapy for long-term treatment success in the presence of PDR or incorporation of routine VL testing to detect VF and change treatment in time, in order to prevent clinical deterioration and accumulation of additional drug resistance. Children ≤3 years should be initiated on a PI-based regimen as per WHO guidelines.

Characterization of HIV-1 subtypes and transmitted drug resistance among treatment-naive HIV-infected individuals in Zhejiang, China, 2014-2017

In recent years, transmitted drug resistance (TDR) has adversely impacted upon first-line therapy for HIV-infected individuals. To understand the current subtype distribution and TDR level in Zhejiang, China we performed phylogenetic analysis and genotypic drug resistance testing of treatment-naive HIV-infected individuals. A total of 153 HIV-1 Pol genes were successfully amplified. The distribution of HIV-1 genotypes was as follows: CRF01_AE (43.8%); CRF07_BC (37.9%); subtype B/B' (7.2%); CRF08_BC (5.2%); and others (5.9%). Drug resistance analysis demonstrated that 11.1% of isolates contained at least one NRTI or NNRTI resistance-associated mutations while 2.0% were identified to be resistant to PIs. These findings enhance our understanding of the genetic diversity of HIV-1 strains circulating in Zhejiang and provide some guidelines for HIV initial treatment therapy.

The World Health Organization's Response to Emerging Human Immunodeficiency Virus Drug Resistance and a Call for Global Action

The global community, including the World Health Organization (WHO), has committed to ending the AIDS epidemic and to ensuring that 90% of people living with human immunodeficiency virus (HIV) are diagnosed, 90% start treatment, and 90% achieve and maintain virological suppression. The emergence of HIV drug resistance (HIVDR) as antiretroviral treatment programs expand could preclude the 90-90-90 targets adopted by the United Nations General Assembly at the High-Level Meeting on Ending AIDS from being achieved. The Global Action Plan on HIVDR is a call for collective action grounded on normative guidance providing a standardized and robust approach to monitoring, preventing, and responding to HIVDR over the next 5 years (2017-2021). WHO is committed to supporting country, global, regional, and national partners to implement and monitor the progress of the Global Action Plan. This article outlines the key components of WHO's strategy to tackle HIVDR and the role the organization takes in leading the global response to HIVDR.

Prediction of plasma efavirenz concentrations among HIV-positive patients taking efavirenz-containing combination antiretroviral therapy

We investigated the predictors of plasma mid-dose concentrations (C12) of efavirenz by enrolling 456 HIV-positive patients who had received 2 nucleos(t)ide reverse-transcriptase inhibitors plus efavirenz (600 mg daily) for 2 weeks or longer and had their CYP2B6 516G>T polymorphism and efavirenz C12 determined. The median efavirenz C12 was 2.41 mg/L (IQR, 1.93–3.14). In analysis of covariance models, patients with CYP2B6 516GT and TT genotypes compared to those with GG genotype had higher efavirenz C12 (for GT genotype, an increase by 0.976 mg/L [95%CI, 0.765–1.188], and TT genotype, 4.871 mg/L [95%CI, 4.126–5.616]), while per 10-kg increment in weight decreased C12 by 0.199 mg/L (95%CI, 0.111–0.287). Models incorporating CYP2B6 516G>T polymorphism and weight had moderate predictive values in predicting efavirenz C12 ≥ 2 mg/L (ROC area under curve = 0.706 [95%CI, 0.656–0.756]). In the absence of CYP2B6 516G>T polymorphism, weight ≤58 kg provided better predictabilities for efavirenz C12 ≥ 2 mg/L (probability, 77.1% [95%CI, 69.0–83.5%] for weight = 50 kg and 70.6% [95%CI, 64.1–76.4%] for weight = 58 kg).

High rate of HIV-1 drug resistance in treatment failure patients in Taiwan, 2009-2014

Background

Drug resistance to nucleoside reverse transcriptase inhibitors (NRTIs), non-nucleoside reverse transcriptase inhibitors (NNRTIs), and protease inhibitors (PIs) has been associated with loss of viral suppression measured by a rise in HIV-1 RNA levels, a decline in CD4 cell counts, persistence on a failing treatment regimen, and lack of adherence to combination antiretroviral therapy.

Objectives

This study aimed to monitor the prevalence and risk factors associated with drug resistance in Taiwan after failure of first-line therapy.

Materials and methods

Data from the Veterans General Hospital Surveillance and Monitor Network for the period 2009–2014 were analyzed. Plasma samples from patients diagnosed with virologic failure and an HIV-1 RNA viral load >1000 copies/mL were analyzed by the ViroSeq^™ HIV-1 genotyping system for drug susceptibility. Hazard ratios (HRs) for drug resistance were calculated using a Cox proportional hazard model.

Results

From 2009 to 2014, 359 patients were tested for resistance. The median CD4 count and viral load (log) were 214 cells/μL (interquartile range [IQR]: 71–367) and 4.5 (IQR: 3.9–5.0), respectively. Subtype B HIV-1 strains were found in 90% of individuals. The resistance rate to any of the three classes of antiretroviral drugs (NRTI, NNRTI, and PI) was 75.5%. The percentage of NRTI, NNRTI, and PI resistance was 58.6%, 61.4%, and 11.4%, respectively. The risk factors for any class of drug resistance included age ≤35 years (adjusted HR: 2.30, CI: 1.48–3.56; p<0.0001), initial NNRTI-based antiretroviral regimens (adjusted HR: 1.70, CI: 1.10–2.63; p=0.018), and current NNRTI-based antiretroviral regimens when treatment failure occurs (odds ratio: 4.04, CI: 2.47–6.59; p<0.001). There was no association between HIV-1 subtype, viral load, and resistance.

Conclusion

This study demonstrated a high level of resistance to NRTI and NNRTI in patients with virologic failure to first-line antiretroviral therapy despite routine viral load monitoring. Educating younger men who have sex with men to maintain good adherence is crucial, as PI use is associated with lower possibility of drug resistance.

Trends and outcomes of late initiation of combination antiretroviral therapy driven by late presentation among HIV-positive Taiwanese patients in the era of treatment scale-up

OBJECTIVES

The international and national HIV treatment guidelines in 2016 have focused on scaling up access to combination antiretroviral therapy (cART). We aimed to assess the trends and treatment outcomes of late cART initiation in Taiwan.

METHODS

Between June 2012 and May 2016, we retrospectively included antiretroviral-naive HIV-positive adults who initiated cART. Late initiation was defined as when cART was initiated in patients with a CD4 count <200 cells/mm3 or having experienced AIDS-defining illnesses. The treatment outcomes were assessed up to 6 months after starting cART.

RESULTS

We included 3655 HIV-positive patients, and the majority of the patients were male (95.4%) with a median age of 31 years and initiated non-nucleoside reverse-transcriptase inhibitor-containing regimens (87.0%). The median CD4 count at cART initiation increased from 207 cells/mm3 in 2012 to 298 cells/mm3 in 2016, and the overall proportion of late cART initiation decreased from 49.1% in 2012 to 29.0% in 2016 (P for trend <0.001). Late cART initiation mainly resulted from late presentation for HIV care and was associated with older age (per 1-year increase, adjusted odds ratio [AOR], 1.05; 95% CI, 1.04-1.06), HBsAg seropositivity (AOR, 1.31; 95% CI, 1.04-1.64), HIV care in central and southern Taiwan, initiating cART in earlier year, non-intravenous drug users (AOR, 1.96; 95% CI, 1.33-2.86), and negative hepatitis C serostatus (AOR, 1.47; 95% CI, 1.04-2.08). Compared with non-late initiators, late initiators had a higher rate of all-cause mortality (1.7% vs. 0.3%) and regimen modification due to virological failure (7.1% vs. 2.6%). The predicting factors of all-cause mortality were late cART initiation (adjusted hazard ratio [AHR], 5.40; 95% CI, 2.14-13.65) and older age (AHR, 1.06; 95% CI, 1.03-1.10).

CONCLUSIONS

While the proportion of late cART initiation decreased over time in Taiwan, late initiation remained in a substantial proportion of HIV-positive patients. The late initiators had higher risk for poor outcomes. The need for strategies to earlier detection of HIV infection and expediting cART initiation should be highlighted, especially among the older population.

Multicenter study of skin rashes and hepatotoxicity in antiretroviral-naïve HIV-positive patients receiving non-nucleoside reverse-transcriptase inhibitor plus nucleoside reverse-transcriptase inhibitors in Taiwan

OBJECTIVES

Two nucleos(t)ide reverse-transcriptase inhibitors (NRTIs) plus 1 non-NRTI (nNRTI) remain the preferred or alternative combination antiretroviral therapy (cART) for antiretroviral-naive HIV-positive patients in Taiwan. The three most commonly used nNRTIs are nevirapine (NVP), efavirenz (EFV) and rilpivirine (RPV). This study aimed to determine the incidences of hepatotoxicity and skin rashes within 4 weeks of initiation of cART containing 1 nNRTI plus 2 NRTIs.

METHODS

Between June, 2012 and November, 2015, all antiretroviral-naive HIV-positive adult patients initiating nNRTI-containing cART at 8 designated hospitals for HIV care were included in this retrospective observational study. According to the national HIV treatment guidelines, patients were assessed at baseline, 2 and 4 weeks of cART initiation, and subsequently every 8 to 12 weeks. Plasma HIV RNA load, CD4 cell count and aminotransferases were determined. The toxicity grading scale of the Division of AIDS (DAIDS) 2014 was used for reporting clinical and laboratory adverse events.

RESULTS

During the 3.5-year study period, 2,341 patients initiated nNRTI-containing cART: NVP in 629 patients, EFV 1,363 patients, and RPV 349 patients. Rash of any grade occurred in 14.1% (n = 331) of the patients. In multiple logistic regression analysis, baseline CD4 cell counts (per 100-cell/μl increase, adjusted odds ratio [AOR], 1.125; 95% confidence interval [95% CI], 1.031-1.228) and use of NVP (AOR, 2.443; 95% CI, 1.816-3.286) (compared with efavirenz) were independently associated with the development of skin rashes. Among the 1,455 patients (62.2%) with aminotransferase data both at baseline and week 4, 72 (4.9%) developed grade 2 or greater hepatotoxicity. In multiple logistic regression analysis, presence of antibody for hepatitis C virus (HCV) (AOR, 2.865; 95% CI, 1.439-5.704) or hepatitis B surface antigen (AOR, 2.397; 95% CI, 1.150-4.997), and development of skin rashes (AOR, 2.811; 95% CI, 1.051-7.521) were independently associated with the development of hepatotoxicity.

CONCLUSIONS

The baseline CD4 cell counts and use of NVP were associated with increased risk of skin rashes, while hepatotoxicity was independently associated with HCV or hepatitis B virus coinfection, and development of skin rashes in antiretroviral-naïve HIV-positive Taiwanese patients within 4 weeks of initiation of nNRTI-containing regimens.

Genotypic susceptibility score (GSS) and CD4+ T cell recovery in HIV-1 patients with suppressed viral load

OBJECTIVES

HIV drug resistance, measured by the genotypic susceptibility score (GSS), has a deleterious effect on the virological outcome of HIV-1-infected patients. However, it is not known if GSS retains any predictive value for CD4 recovery in patients with suppressed viral load.

METHODS

Four hundred and six patients on virological failure (>500 copies/mL) with GSS  : <6 months prior to switch therapy who achieved undetectable plasma viral load (<50 copies/mL) within 1 year, remained undetectable >1 year on an unchanged regimen and had CD4 data available during entire follow-up were included. Adjusted and unadjusted analyses of all characteristics at switch related to CD4 recovery were made for three time frames: (i) 'switch-suppression'; (ii) 'suppression-1 year'; and (iii) 'switch-1 year'.

RESULTS

Higher GSS was associated with a greater CD4 recovery between 'switch' and '1 year' in the unadjusted analysis (P = 0.010); however, the effect of GSS was no longer statistically significant after adjusting for pre-switch clinical (CD4 count and plasma viral load) and demographic variables. Furthermore, only a lower pre-switch CD4 count was associated with increased CD4 recovery in the 'suppression-1 year' period in both unadjusted and adjusted models. The main CD4 recovery occurred in 'switch-suppression' and the variables associated, both unadjusted and adjusted, were CD4 and plasma viral load at switch, maintaining a trend for GSS (P = 0.06).

CONCLUSIONS

In individuals who re-suppressed HIV viraemia after switching therapy, regimens having a higher GSS were associated with improved CD4 recovery only during the period from switch to virological suppression, but, once viral load is re-suppressed, the GSS of the new regimen has no further effect on subsequent CD4 recovery.

Transmitted drug resistance of HIV-1 strains among individuals attending voluntary counselling and testing in Taiwan

BACKGROUND

Genotypic drug resistance testing for HIV-1 has been integrated into voluntary counselling and testing (VCT) programmes to investigate the trends of transmitted drug resistance (TDR), including integrase mutations, among individuals with recent or chronic HIV infections in Taiwan.

METHODS

Between 2006 and 2014, 745 of 21 886 subjects (3.4%) tested HIV positive in the VCT service. The BED assay was used to identify recent HIV infections. Genotypic resistance mutations were interpreted using the WHO 2009 list. Integrase resistance mutations were analysed using the Stanford HIV Drug Resistance Database.

RESULTS

Three-hundred-and-sixty (48.3%) patients were recently infected with HIV-1. Of 440 patients linked to HIV care with analysable reverse transcriptase and protease genes, 49 (11.1%) were infected with HIV-1 harbouring at least one resistance-associated mutation (RAM). The prevalence of TDR to NRTIs, NNRTIs and PIs was 4.1%, 6.4% and 2.3%, respectively. TDR prevalence did not change significantly during the study period. CD4 counts ≤500 cells/mm(3) and hepatitis B surface antigen positivity were independent factors associated with acquiring drug-resistant HIV. The prevalence of integrase mutations was 3.2%. Among the seven major integrase mutations (T66I, E92Q, G140S, Y143C/H/R, S147G, Q148H/K/R and N155H), only one strain harbouring the Q148R mutation was detected. We found no statistically significant difference between patients with chronic infection and those with recent infection in the prevalence of drug-resistant mutations to any of the four classes of antiretroviral agents.

CONCLUSIONS

The prevalence of TDR of HIV-1 strains to available antiretroviral agents is moderately high, but transmission of HIV-1 with drug-resistant mutations remains stable in Taiwan.

Chemokine co-receptor usage in HIV-1-infected treatment-naïve voluntary counselling and testing clients in Southern Taiwan

OBJECTIVE

The goal of this present study was to determine the proportion of CCR5-tropic and CXCR4-tropic viruses and impact of tropism test on clinical presentation, CD4 cell counts, viral load and genotypic drug resistance from drug-naïve, voluntary counselling and testing (VCT) clients in southern Taiwan.

DESIGN

This was a cross-sectional study. Plasma samples were collected from HIV-1-infected patients from January 2013 to December 2013; subjects were recruited from free VCT centres in southern Taiwan.

SETTING

Taiwan.

PARTICIPANTS

Plasma samples from 108 HIV-1-infected, treatment-naïve, VCT clients were analysed. HIV-1 strains were sequenced, genotype resistance was determined by a commercial kit (Viro-seq) and co-receptor tropism (CRT) was predicted by an internet tool geno2pheno[coreceptor], with a 10% false-positive rate as the cut-off. Differences in progression markers, patient characteristics, VCT questionnaires and HIV subtype distribution were evaluated statistically.

RESULTS

All the 108 VCT clients were male with 90% between the ages of 20 and 40 years. Eighty-eight per cent of the patients were men who have sex with men (MSM). The median (IQR) CD4 cell count was 342 cells/µL (221-454) and the viral load was 4.6 log (4.0-5.0). HIV-transmitted drug resistance was found in 9.3% (10/108) of the patients. CRT predictions indicated that 74% of the patients had only R5-tropic strains. CRT was not associated with CD4 cell counts, patient characteristics, VCT questionnaire and transmitted drug resistance. There was a significant difference with regard to viral load at the time of presentation, showing that patients with R5 more often had a higher viral load as compared with those with X4/DM strains (4.6±0.6 log vs 4.33±0.7 log, p=0.036).

CONCLUSIONS

We found that 74% of the VCT clients were infected with R5-tropic virus strains. HIV-transmitted drug resistance was not associated with CRT predictions. Higher viral load at presentation was predictive of R5 co-receptor usage.

HIV drug resistance mutations in proviral DNA from a community treatment program

Background

Drug resistance mutations archived in resting memory CD4+ cells may persist despite suppression of HIV RNA to <50 copies/ml. We sequenced pol gene from proviral DNA among viremic and suppressed patients to identify drug resistance mutations.

Methods

The Peninsula AIDS Research Cohort study enrolled and followed over 2 years 120 HIV infected patients from San Mateo and San Francisco Counties. HIV-1 pol genotyping by bulk sequencing was performed on 38 DNA and RNA from viremic patients and DNA only among 82 suppressed patients at baseline. Antiretroviral susceptibility was predicted by HIVDB.stanford.edu.

Results

Among 120 subjects, 81% were on antiretroviral therapy and had been treated for a median time of 7 years. Thirty-two viremic patients showed concordant RNA and DNA genotypes (84%); the discordant profiles were mainly observed in patients with low-level viremia. Among suppressed patients, 21 had drug resistance mutations in proviral DNA (26%) with potential resistance to one, two or three ARV classes in 16, 4 and 1 samples respectively.

Conclusions

The high level of genotype concordance between DNA and RNA in viremic patients suggested that DNA genotyping might be used to assess drug resistance in resource-limited settings, and further investigation of extracted DNA from dried blood spots is needed. Drug resistance mutations in proviral DNA in 26% of subjects with less than 50 copies/ml pose a risk for the transmission of drug resistant virus with virologic failure, treatment interruption or decreased adherence.

Incidence and risk factors of skin rashes and hepatotoxicity in HIV-infected patients receiving nevirapine-containing combination antiretroviral therapy in Taiwan

OBJECTIVES

To retrospectively investigate the incidence of and factors associated with skin rashes and hepatotoxicity in HIV-infected patients who initiated combination antiretroviral therapy (cART) containing nevirapine plus two nucleos(t)ide reverse-transcriptase inhibitors.

METHODS

The medical records of HIV-infected adult patients who started nevirapine-containing cART and continued follow-up for ≥4 weeks were reviewed at two hospitals in Taiwan between 2000 and 2012. Clinical data obtained at baseline and during follow-up were collected and analyzed.

RESULTS

Of the 338 patients included in the analysis, 13.0% tested positive for hepatitis B virus surface antigen and 7.9% tested positive for anti-hepatitis C virus antibody. The incidence of rashes was 21.6% and of hepatotoxicity was 25.5%. On multiple logistic regression analysis, a two-fold or greater increase from the upper limit of normal levels of aminotransferases at baseline was associated with rashes (adjusted odds ratio (aOR) 3.74, 95% confidence interval (CI) 1.56-8.96); higher CD4 counts (aOR for per 50 cells/μl increase 1.51, 95% CI 1.12-2.03) and the concurrent use of trimethoprim/sulfamethoxazole (aOR 14.01, 95% CI 1.98-98.95) were associated with hepatotoxicity.

CONCLUSIONS

Abnormal liver function at baseline was significantly associated with skin rashes, while a higher CD4 count and the concurrent use of trimethoprim/sulfamethoxazole were associated with hepatotoxicity after the initiation of nevirapine-containing cART in HIV-infected Taiwanese patients.

Prevalence and associated factors for HIV-1 transmitted drug resistance in voluntary clients for counseling and testing in Southern Taiwan

BACKGROUND

According to the World Health Organization, HIV-transmitted drug resistance (TDR) is increasing. We analyzed voluntary counseling test data from a hospital in Southern Taiwan to investigate the TDR pattern in Southern Taiwan, the potential relationship between sexual behavior and HIV transmission, and HIV drug-resistant strain transmission.

METHODS

Genotypic resistance assays were performed on treatment-naïve HIV patients recruited from voluntary counseling testing (VCT) in Southern Taiwan from 2007 to 2011. Drug resistance-associated mutations were interpreted with Stanford University HIV Drug Resistance Database HIVdb program. Socio-demographics and sexual activity were recorded from the VCT questionnaire. Logistic regression analysis was used to analyze the risk factors for TDR, and a phylogenetic tree was constructed to elucidate the pattern of HIV drug-resistant strains.

RESULTS

Among the 161 treatment-naïve HIV-infected patients, most were men who reported having sex with men. The overall TDR rate was 10.6%. Patients with a history of sexually transmitted diseases had a 7.8-fold higher risk of becoming infected with genotypic resistant strains.

CONCLUSION

In Southern Taiwan, the HIV TDR rate was 10.6% among those receiving VCT. Our findings suggest that sexual behavior may play an important role in HIV drug-resistant strain transmission.

Skin rash related to once-daily boosted darunavir-containing antiretroviral therapy in HIV-infected Taiwanese: incidence and associated factor

OBJECTIVES

The study aimed to investigate the incidence of and associated factors with skin rashes among HIV-infected Taiwanese patients who received once-daily darunavir (DRV) boosted by ritonavir (RTV) (800/100 mg) plus 2 nucleoside reverse-transcriptase inhibitors (NRTIs).

METHODS

We reviewed the medical records of HIV-infected patients who switched to once-daily DRV/RTV-containing regimens between January 2012 and November 2013. Patients who switched from 2 NRTIs plus non-NRTI (nNRTI) or other protease inhibitor (PI) to 2 NRTIs plus PIs other than DRV were chosen as comparators.

RESULTS

During the study period, 238 patients who switched to once-daily DRV/RTV-containing regimens (Group A) and 178 patients who switched from 2 NRTIs plus nNRTI or other PI to 2 NRTIs plus PI other than DRV/RTV (Group B) were included. There were no differences between Groups A and B in most of the baseline characteristics. Compared with Group B in which 7 (3.9%) developed rashes after switch to PI other than DRV, 26 patients (10.9%) in Group A developed rashes after a median interval of 14 days of starting DRV/RTV-containing regimens (P = 0.009). In multivariate analysis, patients with a history of rashes related to the previous nNRTI-containing regimens before starting DRV/RTV-containing regimens were more likely to develop rashes with an adjusted odds ratio of 3.53 (95% confidence interval, 1.45-8.62).

CONCLUSIONS

Once-daily regimens containing DRV/RTV is associated with a higher rate of adverse cutaneous reactions than other PI-containing regimens in HIV-infected Taiwanese, especially in those who have a history of rashes to nNRTI-containing regimens before switch to DRV/RTV-containing regimens.

Update on antiretroviral treatment during primary HIV infection

Primary HIV-1 infection covers a period of around 12 weeks in which the virus disseminates from the initial site of infection into different tissues and organs. In this phase, viremia is very high and transmission of HIV is an important issue. Most guidelines recommend antiretroviral treatment in patients who are symptomatic, although the indication for treatment remains inconclusive in asymptomatic patients. In this article the authors review the main virological and immunological events during this early phase of infection, and discuss the arguments for and against antiretroviral treatment. Recommendations of different guidelines, the issue of the HIV transmission and transmission of resistance to antiretroviral drugs, as well as recently available information opening perspectives for functional cure in patients treated in very early steps of HIV infection are also discussed.

Increasing trends in primary NNRTI resistance among newly HIV-1-diagnosed individuals in Buenos Aires, Argentina

OBJECTIVE

Our objective was to estimate primary resistance in an urban setting in a developing country characterized by high antiretroviral (ARV) coverage over the diagnosed population and also by an important proportion of undiagnosed individuals, in order to determine whether any change in primary resistance occurred in the past five years.

DESIGN

We carried out a multi-site resistance surveillance study according to WHO HIV resistance guidelines, using a weighted sampling technique based on annual HIV case reports per site.

METHODS

Blood samples were collected from 197 drug-naive HIV-1-infected individuals diagnosed between March 2010 and August 2011 at 20 HIV voluntary counselling and testing centres in Buenos Aires. Clinical records of enrolled patients at the time of diagnosis were compiled. Viral load and CD4 counts were performed on all samples. The pol gene was sequenced and the resistance profile determined. Phylogenetic analysis was performed by neighbour-joining (NJ) trees and bootscanning analysis.

RESULTS

We found that 12 (7.9%) of the 152 successfully sequenced samples harboured primary resistance mutations, of which K103N and G190A were the most prevalent. Non-nucleoside reverse transcriptase inhibitors (NNRTI) resistance mutations were largely the most prevalent (5.9%), accounting for 75% of all primary resistance and exhibiting a significant increase (p=0.0072) in prevalence during the past 10 years as compared to our previous study performed in 1997-2000 and in 2003-2005. Nucleoside reverse transcriptase inhibitor (NRTI) and protease inhibitor primary resistance were low and similar to the one previously reported.

CONCLUSIONS

Levels of primary NNRTI resistance in Buenos Aires appear to be increasing in the context of a sustained ARV coverage and a high proportion of undiagnosed HIV-positive individuals.

Monitoring the emergence of resistance mutations in patients infected with HIV-1 under salvage therapy with raltegravir in Rio de Janeiro, Brazil: a follow-up study

The present study describes a follow-up of a prospective and observational cohort of patients infected with HIV-1 and treated with raltegravir for salvage therapy in Brazil. Two groups of patients were analyzed: switching from T20 to RAL (Group 1, n = 9) and salvage therapy containing RAL (Group 2, n = 10). Blood samples were drawn for CD4(+) T-cell counts and HIV-1 viral load determinations. Protease, reverse transcriptase, and integrase genotyping were performed at baseline and at the time of virologic failure. CD4(+) T-cells increased at 6 and 12 months in both groups; HIV-1 viral load was continuously suppressed for Group 1, and for Group 2 it significantly decreased after starting a RAL-containing regimen. Three out of 10 patients from Group 2 could not suppress HIV-1 viral load. The mutations Q148H + G140S were observed for two patients and for the third patient only mutations to PR/RT inhibitors were detected. The genotypic sensitivity score (GSS) was analyzed for all patients of Group 2 and both patients who developed resistance to raltegravir presented a GSS < 2.0 for the RAL-containing scheme, which could be associated to the lack of effectiveness of the proposed scheme. The present study describes, for the first time in Brazil, the close follow-up of a series of patients using a raltegravir-containing HAART, showing the safety of the enfuvirtide switch to RAL and the effectiveness of a therapeutic regimen with RAL in promoting immune reconstitution and suppressing HIV replication, as well as documenting the occurrence of resistance to integrase inhibitors in the country.