HIV-1 drug resistance mutations among antiretroviral-naive HIV-1-infected patients in Asia: results from the TREAT Asia Studies to Evaluate Resistance-Monitoring Study

Immunological and molecular assessment of HIV-1 mutations for antiretroviral drug resistance in Saudi Arabia

Human Immunodeficiency Virus (HIV) is a significant threat to public health. HIV genotyping and antiretroviral resistance testing may have contributed to improved non-treated management. Immune markers might assist HIV-1 diagnosis and drug-resistant variant identification. HIV-1 immunogenicity and molecular characteristics of antiretroviral drug resistance are evaluated in 56 treatment-naive HIV patients. DNA sequencing and retroviral resistance testing identified HIV-1 genotypes. 55.4% of patients were susceptible to protease inhibitors (PI), nucleoside reverse transcriptase inhibitors (NRTI), and non-nucleoside reverse transcriptase inhibitors (NNRTI) antiretroviral drugs, whereas 44.6% had drug-resistance mutations against at least one antiretroviral drug. 3.6% of cases had PI-resistant mutations, while 30.4% had NRTI-resistant mutations, and 30.4% had NNRTI-resistant mutations. In patients who are susceptible to PI, the mean value of human plasma sCD80 is 2.11 ± 0.65 ng/mL; in patients with mutations, it is 3.93 ± 2.91 ng/mL. Individuals who are susceptible to PI have plasma sCD27 levels of 78.7 ± 63.2 U/mL, whereas individuals who are mutant have levels of 56.5 ± 32.1 U/mL. IP-10's mean value was 363 ± 109.2 pg/mL for the susceptible patients and 429 ± 20.7 pg/mL for the mutated patients. In susceptible patients, the plasma sCD4 level is 0.163 ± 0.229 ng/mL; in mutant patients, it is 0.084 ± 0.012 ng/mL. The data showed a relative relation between immunological parameters such as sCD80, sCD27, sCD4, and IP-10 and mutation for drug resistance.

A systematic review and meta-analysis of HIV transmission risk behaviors, genetic variations, and antiretroviral (ARV) resistance in LGBT populations

Background

Currently, human immunodeficiency virus and acquired immunodeficiency syndrome (HIV/AIDS) has become one of the major health problems worldwide, including Indonesia. East Java is one of the provinces in Indonesia with the highest prevalence of HIV infection. One of the causes of HIV infection transmission is lesbian, gay, bisexual, and transgender (LGBT) practice. Furthermore, the treatment using antiretroviral (ARV) drugs in HIV-1 patients can fail due to the presence of HIV drug resistance.

Objective

The aim of this study is to identify the behavior at risk of HIV transmission among LGBT, patterns of genetic variation and antiretroviral (ARV) resistance.

Methods

A systematic review and meta-analysis based on the PRISMA guidelines was conducted. We searched three databases including PubMed, ScienceDirect, and Google scholar for studies investigating the non-heterosexual behavior as risk factor of HIV infection and antiretroviral resistance. Only studies published in English are considered. The adjusted estimates of the risk were carried out using best-adjusted OR with 95% confidence interval (CI) and significant p value < 0.05.

Results

In the quantitative analysis of HIV infection risk factors, a total of 13 studies were included, which investigated non-heterosexual behavior as a potential factor. The studies involved a total of 37,129 participants, comprising 10,449 individuals in the non-heterosexual behavior group (LGBTQ+) and 26,680 individuals in the heterosexual group. The majority of the participants in this study were from the USA, Japan, China, and Brazil, and the main HIV subgenotypes were B and CRF. Additionally, the antiretroviral resistance of HIV patients was examined, involving a total of 3062 individuals, with 1296 individuals in the non-heterosexual behavior group and 1766 individuals in the heterosexual group. Our calculation showed that non-heterosexual behavior was significant as risk factor of HIV infection (OR = 2.17, 95% CI = 1.94-2.43, p < 0.001) and antiretroviral resistance (OR = 1.31, 95% CI = 1.00-1.71, p = 0.05).

Conclusion

This study concludes that non heterosexual behavior is significant risk factor of HIV infection. A quite prevalent of antiretroviral resistance were found among non heterosexual behavior. The main subgenotype of HIV are B and CRF.

Nucleoside Analog 2',3'-Isopropylidene-5-Iodouridine as Novel Efficient Inhibitor of HIV-1

Nucleoside reverse transcriptase inhibitors are the first class of drugs to be approved by the FDA for the suppression of HIV-1 and are widely used for this purpose in combination with drugs of other classes. Despite the progress in HIV-1 treatment, there is still the need to develop novel efficient antivirals. Here the efficiency of HIV-1 inhibition by a set of original 5-substituted uridine nucleosides was studied. We used the replication deficient human immunodeficiency virus (HIV-1)-based lentiviral particles and identified that among the studied compounds, 2',3'-isopropylidene-5-iodouridine was shown to cause anti-HIV-1 activity. Importantly, no toxic action of this compound against the cells of T-cell origin was found. We determined that this compound is significantly more efficient at suppressing HIV-1 compared to Azidothymidine (AZT) when taken at the high non-toxic concentrations. We did not find any profit when using AZT in combination with 2',3'-isopropylidene-5-iodouridine. 2',3'-Isopropylidene-5-iodouridine acts synergistically to repress HIV-1 when combined with the CDK4/6 inhibitor Palbociclib in low non-toxic concentration. No synergistic antiviral action was detected when AZT was combined with Palbociclib. We suggest 2',3'-isopropylidene-5-iodouridine as a novel perspective non-toxic compound that may be used for HIV-l suppression.

Long-term virological and immunological outcomes between HIV-positive individuals with and without pretreatment HIV drug resistance

BACKGROUND

Pretreatment HIV drug resistance (PHDR) has emerged after scaling-up access to antiretroviral therapy (ART). This study aimed to compare long-term virological and immunological outcomes between HIV-positive individuals with and without PHDR.

METHODS

An observational cohort study was conducted in HIV-positive individuals who had a genotypic resistance test performed prior to ART initiation.

RESULTS

Of 335 participants, 39 were in the PHDR group and 296 were in the control group. ART regimen in PHDR group was adjusted at 6-10 weeks after ART initiation when results of baseline genotypic resistance test were available. Proportions of participants with undetectable viral load were significantly lower in PHDR group at 6 and 12 months (46.2% vs 79.4% (p < .001) and 74.4% vs 90.5% (p = .003), respectively). These virological responses became similar between two groups (p > .05) from 18 through 60 months. Mean change of CD4 counts of PHDR group was significantly lower only at 6 months (+59 vs + 81 cells/mm³ (p = .012); these immunological responses were similar between two groups from 12 through 60 months.

CONCLUSION

Early virological response was lower in HIV-positive participants with PHDR compared to participants without PHDR. Subsequent adjustment of ART according to pretreatment genotypic resistance has contributed to the long-term virological and immunological success that is similar to participants without PHDR.

Increase in HIV-1-transmitted drug resistance among ART-naïve youths at the China-Myanmar border during 2009 ~ 2017

Background

HIV-transmitted drug resistance (TDR) is found in antiretroviral therapy (ART)-naïve populations infected with HIV-1 with TDR mutations and is important for guiding future first- and second-line ART regimens. We investigated TDR and its effect on CD4 count in ART-naïve youths from the China-Myanmar border near the Golden Triangle to better understand TDR and effectively guide ART.

Methods

From 2009 to 2017, 10,832 HIV-1 infected individuals were newly reported along the Dehong border of China, 573 ART-naïve youths (16 ~ 25 y) were enrolled. CD4 counts were obtained from whole blood samples. HIV pol gene sequences were amplified from RNA extracted from plasma. The Stanford REGA program and jpHMM recombination prediction tool were used to determine genotypes. TDR mutations (TDRMs) were analyzed using the Stanford Calibrated Population Resistance tool.

Results

The most common infection route was heterosexuals (70.51%), followed by people who inject drugs (PWID, 19.20%) and men who have sex with men (MSM) (8.90%). The distribution of HIV genotypes mainly included the unique recombinant form (URF) (44.08%), 38.68% were CRFs, 13.24% were subtype C and 4.04% were subtype B. The prevalence of TDR increased significantly from 2009 to 2017 (3.48 to 9.48%) in ART-naïve youths (4.00 to 13.16% in Burmese subjects, 3.33 to 5.93% in Chinese subjects), and the resistance to non-nucleoside reverse transcriptase inhibitors (NNRTIs), nucleoside and nucleotide reverse transcriptase inhibitors (NRTIs), and protease inhibitors (PIs) were 3.49, 2.62, and 0.52%, respectively. Most (94.40%, n = 34) of HIV-1-infected patients with TDRM had mutation that conferred resistance to a single drug class. The most common mutations Y181I/C and K103N, were found in 7 and 9 youths, respectively. The mean CD4 count was significantly lower among individuals with TDRMs (373/mm³ vs. 496/mm³, p = 0.013).

Conclusions

The increase in the prevalence of HIV-1 TDR increase and a low CD4 count of patients with TDRMs in the China-Myanmar border suggests the need for considering drug resistance before initiating ART in HIV recombination hotspots.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12879-021-05794-5.

Genotyping and antiretroviral drug resistance of human immunodeficiency Virus-1 in Jazan, Saudi Arabia

Determination of human immunodeficiency virus-1 (HIV-1) genotypes and identification of antiretroviral drug-resistant mutations. Among treatment naïve HIV patients in Jazan, Saudi Arabia. HIV is a major public health problem. HIV genotyping and antiretroviral resistance testing is an important guide for better management of treatment-naive. Antiretroviral resistance testing before starting of treatment regimen leads to a better virological response. A total of 57 samples of treatment-naive patients were collected from King Fahd Central Hospital in Jazan, Saudi Arabia. Samples were tested for HIV-1 antibodies, western blot, viral load, HIV-1 genotypes through direct sequencing, and antiretroviral resistance testing. The HIV-1 Genotypes were as follow; C: 66.6%, D: 10.5%, G: 8.8%, B: 7.0%, CRF01_AE: 3.5%, A and CRF02_AG: 1.8% each. 77.2% of cases showed susceptibility to the 3 major classes of antiretroviral drugs; Protease inhibitor (PI), Nucleoside reverse transcriptase inhibitor (NRTI), and non-nucleoside reverse transcriptase inhibitors (NNRTI); while 8.8% had mutations conferring resistance to NRTI. Mutations conferring resistance to PI were detected in 7.0% of cases, and 1.8% of cases had mutations conferring resistance to both NRTI and PI. Mutations conferring resistance to NNRTI were detected in 5.3% of cases. Mutations associated with antiretroviral drugs include (V82A+I84IV), (L10F+Q58E), (L10F+V82Y), L10FV, L33LF, L89LMV, M184V, E138A, V106I, and V179VD. The prevalence of HIV-1 antiretroviral resistance mutations is 22.8% in the studied population, which may warrant antiretroviral drug resistance testing as a pretreatment to help and guide physicians for the proper HIV treatment.

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 Role of ARV Associated Adverse Drug Reactions in Influencing Adherence Among HIV-Infected Individuals: A Systematic Review and Qualitative Meta-Synthesis

Poor adherence remains a major barrier to achieving the clinical and public health benefits of antiretroviral drugs (ARVs). A systematic review and qualitative meta-synthesis was conduct to evaluate how ARV adverse drug reactions may influence ARV adherence. Thirty-nine articles were identified, and 33 reported that ARV adverse drug reactions decreased adherence and six studies found no influence. Visually noticeable adverse drug reactions and psychological adverse reactions were reported as more likely to cause non-adherence compared to other adverse drug reactions. Six studies reported a range of adverse reactions associated with EFV-containing regimens contributing to decreased adherence. Informing HIV-infected individuals about ARV adverse drug reactions prior to initiation, counselling about coping mechanisms, and experiencing the effectiveness of ARVs on wellbeing may improve ARV adherence.

A Decade of Combination Antiretroviral Treatment in Asia: The TREAT Asia HIV Observational Database Cohort

Asian countries have seen the expansion of combination antiretroviral therapy (cART) over the past decade. The TREAT Asia HIV Observational Database (TAHOD) was established in 2003 comprising 23 urban referral sites in 13 countries across the region. We examined trends in treatment outcomes in patients who initiated cART between 2003 and 2013. Time of cART initiation was grouped into three periods: 2003-2005, 2006-2009, and 2010-2013. We analyzed trends in undetectable viral load (VL; defined as VL <400 copies/ml), CD4 changes from pre-cART levels, and overall survival. Of 6,521 patients included, the overall median CD4 count at cART initiation was 120 cells/μl (interquartile range: 38-218). Despite an increase over time, pre-cART CD4 counts remained <200 cells/μl. Adjusted analyses showed undetectable VL was more likely when starting cART in later years [2006-2009: odds ratio (OR) = 1.76, 95% confidence interval (CI) (1.45, 2.15); and 2010-2013: OR = 3.04, 95% CI (2.33, 3.97), all p < .001, compared to 2003-2005], and survival was improved [2006-2009: subdistribution hazard ratio (SHR) = 0.41, 95% CI (0.27, 0.61), 2010-2013: SHR = 0.29, 95% CI (0.17, 0.49), all p < .001, compared to 2003-2005]. No differences in CD4 response was observed over time. Age and CD4 levels prior to cART initiation were associated with all three treatment outcomes, with older age and higher CD4 counts being associated with undetectable VL. Survival and VL response on cART have improved over the past decade in TAHOD, although CD4 count at cART initiation remained low. Greater effort should be made to facilitate earlier HIV diagnosis and linkage to care and treatment, to achieve greater improvements in treatment outcomes.

Prevalence of Transmitted HIV Drug Resistance Among Recently Infected Persons in San Diego, CA 1996-2013

BACKGROUND

Transmitted drug resistance (TDR) remains an important concern when initiating antiretroviral therapy (ART). Here, we describe the prevalence and phylogenetic relationships of TDR among ART-naive, HIV-infected individuals in San Diego from 1996 to 2013.

METHODS

Data were analyzed from 496 participants of the San Diego Primary Infection Cohort who underwent genotypic resistance testing before initiating therapy. Mutations associated with drug resistance were identified according to the WHO-2009 surveillance list. Network and phylogenetic analyses of the HIV-1 pol sequences were used to evaluate the relationships of TDR within the context of the entire cohort.

RESULTS

The overall prevalence of TDR was 13.5% (67/496), with an increasing trend over the study period (P = 0.005). TDR was predominantly toward nonnucleoside reverse transcriptase inhibitors (NNRTIs) [8.5% (42/496)], also increasing over the study period (P = 0.005). By contrast, TDR to protease inhibitors and nucleos(t)ide reverse transcriptase inhibitors were 4.4% (22/496) and 3.8% (19/496), respectively, and did not vary with time. TDR prevalence did not differ by age, gender, race/ethnicity, or risk factors. Using phylogenetic analysis, we identified 52 transmission clusters, including 8 with at least 2 individuals sharing the same mutation, accounting for 23.8% (16/67) of the individuals with TDR.

CONCLUSIONS

Between 1996 and 2013, the prevalence of TDR significantly increased among recently infected ART-naive individuals in San Diego. Around one-fourth of TDR occurred within clusters of recently infected individuals. These findings highlight the importance of baseline resistance testing to guide selection of ART and for public health monitoring.

Prevalence of Primary HIV Drug Resistance in Thailand Detected by Short Reverse Transcriptase Genotypic Resistance Assay

BACKGROUND

HIV drug resistance (HIVDR) is the major cause of treatment failure after scaling up of antiretroviral therapy (ART). HIVDR testing prior to ART initiation is not routinely performed in resource-limited settings. We aimed to assess the prevalence of primary HIVDR by short reverse transcriptase (RT) genotypic resistance assay and evaluate of the impact of the mutations on the treatment outcomes.

METHODS

A prospective cohort study was conducted in treatment-naïve HIV-infected patients. Fourteen major mutations of codon 99-191 on the RT gene were selected (K103N, V106A/M, V108I, Q151M, Y181C/I, M184V/I, Y188C/L/H, and G190S/A) at a cost of testing of 35 USD. The association between the presence of primary HIVDR and undetectable HIV RNA (<50 copies/mL) after 6 months of ART was determined.

RESULTS

A total of 265 HIV-infected patients were included, with a median age of 35.2 (range, 16.8-75.2) years; 62.6% were males. The median (interquartile range) CD4 cell count at ART initiation was 216 (77-381) cells/mm3. The overall prevalence of primary HIVDR was 7.9%. The prevalence of each HIVDR mutation were K103N 6.0%, V106I 1.1%, V108I 0.4%, Y181C 2.3%, Y181I 0.7%, Y181V 0.4%, M184V 3.0%, M184I 1.5%, and G190A 2.3%. No associated factor of having primary HIVDR was determined. By multiple stepwise logistic regression, factors associated with undetectable HIV RNA after 6 months of ART were: having M184V/I (odds ratio [OR] 0.11; 95% confidence interval [CI] 0.02-0.62, p = 0.013), condom use (OR 2.38; 95% CI 1.12-5.06, p = 0.024), and adherence per 5% increase (OR 1.16; 95% CI 1.00-1.35, p = 0.044).

CONCLUSIONS

The prevalence of primary HIVDR is approximately 8%; it is associated with detectable HIV RNA at 6 months after ART initiation. Routine "short RT" genotypic resistance assay should be considered in resource-limited settings to maximize treatment outcome.

Sexual risk behaviors among HIV-patients receiving antiretroviral therapy in Southern Thailand: roles of antiretroviral adherence and serostatus disclosure

The objective of this study was to examine the extent of unprotected sex among patients already established in HIV-medical care and their associated factors. Sexually active patients who were receiving antiretroviral therapy (ART) from five public hospitals in Trang province, Southern Thailand, were interviewed. Of 279 studied patients, 37.3% had unprotected sex in the prior 3 months and 27.2% did not disclose their serostatus to sexual partners. The median duration interquartile range (IQR) of using ART was 47 (27-60) months and 26.7% were non-adherent to ART (i.e., taking less than 95% of the prescribed doses). More than one-third had the perception that ART use would protect against HIV transmission even with unprotected sex. About 36.6% reported that they were unaware of their current CD4 counts and nearly one-third did not receive any safe sex counseling at each medical follow-up. After adjustment for potential confounders, non-adherence to ART and HIV-nondisclosure were strongly associated with an increase in the risk of unprotected sex with the adjusted odds ratio (aOR) of 5.03 (95% CI 2.68-9.44) and 3.89 (95% CI 1.57-9.61), respectively. In contrast, the risk for engaging in unprotected sex was less likely among patients having a negative-serostatus partner (aOR = 0.30; 95% CI 0.12-0.75), a longer duration of the use of ART (aOR = 0.98; 95%CI 0.97-0.99) and an unawareness of their current CD4 levels (aOR = 0.54; 95% CI 0.30-0.99). To maximize the benefits from ART, there should be a bigger emphasis on the "positive prevention" program and more efforts are needed to target the population at risk for unprotected sex. Strategies to encourage adherence to ART and for disclosure of serostatus are also required.

In vitro antiretroviral activity and in vivo toxicity of the potential topical microbicide copper phthalocyanine sulfate

Background

Copper has antimicrobial properties and has been studied for its activity against viruses, including HIV. Copper complexed within a phthalocyanine ring, forming copper (II) phthalocyanine sulfate (CuPcS), may have a role in microbicide development when used intravaginally.

Methods

CuPcS toxicity was tested against cervical epithelial cells, TZM-BL cells, peripheral blood mononuclear cells (PBMC), and cervical explant tissues using cell viability assays. In vivo toxicity was assessed following intravaginal administration of CuPcS in female BALB/C mice and measured using a standardized histology grading system on reproductive tract tissues. Efficacy studies for preventing infection with HIV in the presence of various non-toxic concentrations of CuPcS were carried out in TZM-BL, PBMC, and cervical explant cultures using HIV-1_BAL and various pseudovirus subtypes. Non-linear regression was applied to the data to determine the EC50/90 and CC50/90.

Results

CuPcS demonstrated inhibition of HIV infection in PBMCs at concentrations that were non-toxic in cervical epithelial cells and PBMCs with EC50 values of approximately 50 μg/mL. Reproductive tract tissue analysis revealed no toxicity at 100 mg/mL. Human cervical explant tissues challenged with HIV in the presence of CuPcS also revealed a dose–response effect at preventing HIV infection at non-toxic concentrations with an EC50 value of 65 μg/mL.

Conclusion

These results suggest that CuPcS may be useful as a topical microbicide in concentrations that can be achieved in the female genital tract.

Electronic supplementary material

The online version of this article (doi:10.1186/s12985-015-0358-5) contains supplementary material, which is available to authorized users.

Comparison of genotypic and virtual phenotypic drug resistance interpretations with laboratory-based phenotypes among CRF01_AE and subtype B HIV-infected individuals

HIV drug resistance assessments and interpretations can be obtained from genotyping (GT), virtual phenotyping (VP) and laboratory-based phenotyping (PT). We compared resistance calls obtained from GT and VP with those from PT (GT-PT and VP-PT) among CRF01_AE and subtype B HIV-1 infected patients. GT predictions were obtained from the Stanford HIV database. VP and PT were obtained from Janssen Diagnostics BVBA's vircoType(TM) HIV-1 and Antivirogram®, respectively. With PT assumed as the "gold standard," the area under the curve (AUC) and the Bland-Altman plot were used to assess the level of agreement in resistance interpretations. A total of 80 CRF01_AE samples from Asia and 100 subtype B from Janssen Diagnostics BVBA's database were analysed. CRF01_AE showed discordances ranging from 3 to 27 samples for GT-PT and 1 to 20 samples for VP-PT. The GT-PT and VP-PT AUCs were 0.76-0.97 and 0.81-0.99, respectively. Subtype B showed 3-61 discordances for GT-PT and 2-75 discordances for VP-PT. The AUCs ranged from 0.55 to 0.95 for GT-PT and 0.55 to 0.97 for VP-PT. Didanosine had the highest proportion of discordances and/or AUC in all comparisons. The patient with the largest didanosine FC difference in each subtype harboured Q151M mutation. Overall, GT and VP predictions for CRF01_AE performed significantly better than subtype B for three NRTIs. Although discrepancies exist, GT and VP resistance interpretations in HIV-1 CRF01_AE strains were highly robust in comparison with the gold-standard PT.

Viral Genetic Diversity and Polymorphisms in a Cohort of HIV-1-Infected Patients Eligible for Initiation of Antiretroviral Therapy in Abuja, Nigeria

Studying the genetic diversity and natural polymorphisms of HIV-1 would benefit our understanding of HIV drug resistance (HIVDR) development and predict treatment outcomes. In this study, we have characterized the HIV-1 genetic diversity and natural polymorphisms at the 5' region of the pol gene encompassing the protease (PR) and reverse transcriptase (RT) from 271 plasma specimens collected in 2008 from HIV-1-infected patients who were eligible for initiating antiretroviral therapy in Abuja (Nigeria). The analysis indicated that the predominant subtype was subtype G (31.0%), followed by CRF02-AG (19.2 %), CRF43-02G (18.5%), and A/CRF36-cpx (11.4%); the remaining (19.9%) were other subtypes and circulating (CRF) and unique (URF) recombinant forms. Recombinant viruses (68.6%) were the major viral strains in the region. Eighty-four subtype G sequences were further mainly classified into two major and two minor clusters; sequences in the two major clusters were closely related to the HIV-1 strains in two of the three major subtype G clusters detected worldwide. Those in the two minor clusters appear to be new subtype G strains circulating only in Abuja. The pretreatment DR prevalence was <3%; however, numerous natural polymorphisms were present. Eleven polymorphic mutations (G16E, K20I, L23P, E35D, M36I, N37D/S/T, R57K, L63P, and V82I) were detected in the PR that were subtype or CRF specific while only three mutations (D123N, I135T, and I135V) were identified in the RT. Overall, this study indicates an evolving HIV-1 epidemic in Abuja with recombinant viruses becoming the dominant strains and the emergence of new subtype G strains; pretreatment HIVDR was low and the occurrence of natural polymorphism in the PR region was subtype or CRF dependent.

MQ, Sukartiningrum SD, Nasronudin, Kameoka M. Appearance of drug resistance-associated mutations in human immunodeficiency virus type 1 protease and reverse transcriptase derived from drug-treated Indonesian patients

Although HIV-1 drug resistance is a major obstacle in Indonesia, information on drug resistance is limited. In this study, the viral subtype and appearance of drug resistance mutations in the HIV-1 protease (PR) and reverse transcriptase (RT) genes were determined among drug-treated, HIV-1-infected patients in Surabaya. HIV-1 patients who received antiretroviral therapy (ART) more than 2 years were randomly recruited regardless of the viral load or ART failure. Fifty-eight HIV-1 PR genes and 53 RT genes were sequenced. CRF01_AE viruses were identified as the predominant strain. Major drug resistance mutations were not detected in the PR genes. In contrast, 37.7% (20/53) of the participants had one or more major drug resistance mutations in the RT genes, predominantly M184V (28.3%), K103N (11.3%), and thymidine analogue mutations (TAMs) (20.8%). The high prevalence of drug resistance mutations in RT genes indicated the necessity of monitoring the effectiveness of ART in Indonesia.

Genotypes and transmitted drug resistance among treatment-naive HIV-1-infected patients in a northwestern province, China: trends from 2003 to 2013

Background

Transmitted drug resistance (TDR) reduces the efficacy of initial antiretroviral treatment and has become a public health concern. Little information is available regarding the genetic diversity of HIV-1 and the prevalence of TDR among treatment-naïve patients in a northwestern province of China since the implementation of national free antiretroviral therapy (ART).

Methods

Blood samples from 372 HIV-1 treatment-naive patients were collected between 2003 and 2013 in Shaanxi province. Viral RNA was extracted for nested PCR, and phylogenetic reconstruction and recombination analyses were performed to characterize patterns of the HIV-1 subtypes. Genotypic drug resistance testing was performed using an in-house assay to determine trends in the prevalence of HIV-1 transmitted drug resistance.

Results

Multiple genotypes were identified among the patients in Shaanxi, including B (25.0%), C (0.3%), G (0.3%), and CRF01_AE (39.2%), CRF07_BC (32.7%), CRF08_BC (0.8%), CRF55_01B (1.1%), and URFs (0.6%). The subtypes were associated with the transmission routes (χ² = 77.113, p<0.01). In this study, a low baseline CD4⁺ T cell count and a high viral load were found among CRF01_AE-infected patients compared with patients who were infected with non-CRF01_AE (p<0.01) through sexual transmission; however, the CRF01_AE subtype was not associated with a low baseline CD4⁺ T cell count or a high viral load in Chinese patients infected through blood transmission (p = 0.249). The overall TDR rate in this population was 4.4% between 2003 and 2013. A univariate logistic regression model revealed that a low CD4 T cell count (≤100 cells/µL) was associated with the development of drug-resistant strains.

Conclusion

Our work revealed diverse HIV-1 subtype distributions in Shaanxi province. We identified a low and stable TDR time trend among ART-naive patients. These findings enhance our understanding of HIV-1 genetic diversity and provide some guidelines for the improvement and implementation of a comprehensive public health strategy of HIV-1 TDR prevention.

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.

Transmitted drug resistance and antiretroviral treatment outcomes in non-subtype B HIV-1-infected patients in South East Asia

BACKGROUND

We compared treatment outcomes of transmitted drug resistance (TDR) in patients on fully or partially sensitive drug regimens.

METHODS

Factors associated with survival and failure were analyzed using Cox proportional hazards and discrete time conditional logistic models.

RESULTS

TDR, found in 60 (4.1%) of 1471 Asian treatment-naive patients, was one of the significant predictors of failure. Patients with TDR to >1 drug in their regimen were >3 times as likely to fail compared to no TDR.

CONCLUSIONS

TDR was associated with failure in the context of non-fully sensitive regimens. Efforts are needed to incorporate resistance testing into national treatment programs.

Challenges and potential barriers to the uptake of antiretroviral-based prevention in Asia and the Pacific region

Evidence has emerged over the past few years on the effectiveness of antiretroviral-based prevention technologies to prevent (i) HIV transmission while decreasing morbidity and mortality in HIV-infected persons, and (ii) HIV acquisition in HIV-uninfected individuals through pre-exposure prophylaxis (PrEP). Only few of the planned studies on treatment as prevention (TasP) are conducted in Asia. TasP might be more feasible and effective in concentrated rather than in generalised epidemics, as resources for HIV testing and antiretroviral treatment could focus on confined and much smaller populations than in the generalised epidemics observed in sub-Saharan Africa. Several countries such as Cambodia, China, Thailand and Vietnam, are now paving the way to success. Similar challenges arise for both TasP and PrEP. However, the operational issues for PrEP are amplified by the need for frequent retesting and ensuring adherence. This paper describes challenges for the implementation of antiretroviral-based prevention and makes the case that TasP and PrEP implementation research in Asia is much needed to provide insights into the feasibility of these interventions in populations where firm evidence of ‘real world’ effectiveness is still lacking.

Molecular characterization of ambiguous mutations in HIV-1 polymerase gene: implications for monitoring HIV infection status and drug resistance

Detection of recent HIV infections is a prerequisite for reliable estimations of transmitted HIV drug resistance (t-HIVDR) and incidence. However, accurately identifying recent HIV infection is challenging due partially to the limitations of current serological tests. Ambiguous nucleotides are newly emerged mutations in quasispecies, and accumulate by time of viral infection. We utilized ambiguous mutations to establish a measurement for detecting recent HIV infection and monitoring early HIVDR development. Ambiguous nucleotides were extracted from HIV-1 pol-gene sequences in the datasets of recent (HIVDR threshold surveys [HIVDR-TS] in 7 countries; n=416) and established infections (1 HIVDR monitoring survey at baseline; n=271). An ambiguous mutation index of 2.04×10^-3 nts/site was detected in HIV-1 recent infections which is equivalent to the HIV-1 substitution rate (2×10^-3 nts/site/year) reported before. However, significantly higher index (14.41×10^-3 nts/site) was revealed with established infections. Using this substitution rate, 75.2% subjects in HIVDR-TS with the exception of the Vietnam dataset and 3.3% those in HIVDR-baseline were classified as recent infection within one year. We also calculated mutation scores at amino acid level at HIVDR sites based on ambiguous or fitted mutations. The overall mutation scores caused by ambiguous mutations increased (0.54×10^-23.48×10^-2/DR-site) whereas those caused by fitted mutations remained stable (7.50-7.89×10^-2/DR-site) in both recent and established infections, indicating that t-HIVDR exists in drug-naïve populations regardless of infection status in which new HIVDR continues to emerge. Our findings suggest that characterization of ambiguous mutations in HIV may serve as an additional tool to differentiate recent from established infections and to monitor HIVDR emergence.

Evaluating immunologic response and clinical deterioration in treatment-naive patients initiating first-line therapies infected with HIV-1 CRF01_AE and subtype B

BACKGROUND

HIV-1 group M viruses diverge 25%-35% in envelope, important for viral attachment during infection, and 10%-15% in the pol region, under selection pressure from common antiretrovirals. In Asia, subtypes B and CRF01_AE are common genotypes. Our objectives were to determine whether clinical, immunological, or virological treatment responses differed by genotype in treatment-naive patients initiating first-line therapy.

METHODS

Prospectively collected longitudinal data from patients in Thailand, Hong Kong, Malaysia, Japan, Taiwan, and South Korea were provided for analysis. Covariates included demographics, hepatitis B and C coinfections, baseline CD4 T lymphocyte count, and plasma HIV-1 RNA levels. Clinical deterioration (a new diagnosis of Centers for Disease Control and Prevention category B/AIDS-defining illness or death) was assessed by proportional hazards models. Surrogate endpoints were 12-month change in CD4 cell count and virologic suppression post therapy, evaluated by linear and logistic regression, respectively.

RESULTS

Of 1105 patients, 1036 (93.8%) infected with CRF01_AE or subtype B were eligible for inclusion in clinical deterioration analyses and contributed 1546.7 person-years of follow-up (median: 413 days, interquartile range: 169-672 days). Patients >40 years demonstrated smaller immunological increases (P = 0.002) and higher risk of clinical deterioration (hazard ratio = 2.17; P = 0.008). Patients with baseline CD4 cell counts >200 cells per microliter had lower risk of clinical deterioration (hazard ratio = 0.373; P = 0.003). A total of 532 patients (48.1% of eligible) had CD4 counts available at baseline and 12 months post therapy for inclusion in immunolgic analyses. Patients infected with subtype B had larger increases in CD4 counts at 12 months (P = 0.024). A total of 530 patients (48.0% of eligible) were included in virological analyses with no differences in response found between genotypes.

CONCLUSIONS

Results suggest that patients infected with CRF01_AE have reduced immunologic response to therapy at 12 months, compared with subtype B-infected counterparts. Clinical deterioration was associated with low baseline CD4 counts and older age. The lack of differences in virologic outcomes suggests that all patients have opportunities for virological suppression.

Capacity building and predictors of success for HIV-1 drug resistance testing in the Asia-Pacific region and Africa

BACKGROUND

The TREAT Asia Quality Assessment Scheme (TAQAS) was developed as a quality assessment programme through expert education and training, for laboratories in the Asia-Pacific and Africa that perform HIV drug-resistance (HIVDR) genotyping. We evaluated the programme performance and factors associated with high-quality HIVDR genotyping.

METHODS

Laboratories used their standard protocols to test panels of human immunodeficiency virus (HIV)-positive plasma samples or electropherograms. Protocols were documented and performance was evaluated according to a newly developed scoring system, agreement with panel-specific consensus sequence, and detection of drug-resistance mutations (DRMs) and mixtures of wild-type and resistant virus (mixtures). High-quality performance was defined as detection of ≥95% DRMs.

RESULTS

Over 4.5 years, 23 participating laboratories in 13 countries tested 45 samples (30 HIV-1 subtype B; 15 non-B subtypes) in nine panels. Median detection of DRMs was 88-98% in plasma panels and 90-97% in electropherogram panels. Laboratories were supported to amend and improve their test outcomes as appropriate. Three laboratories that detected <80% DRMs in early panels demonstrated subsequent improvement. Sample complexity factors - number of DRMs (p<0.001) and number of DRMs as mixtures (p<0.001); and laboratory performance factors - detection of mixtures (p<0.001) and agreement with consensus sequence (p<0.001), were associated with high performance; sample format (plasma or electropherogram), subtype and genotyping protocol were not.

CONCLUSION

High-quality HIVDR genotyping was achieved in the TAQAS collaborative laboratory network. Sample complexity and detection of mixtures were associated with performance quality. Laboratories conducting HIVDR genotyping are encouraged to participate in quality assessment programmes.

Comparisons of Primary HIV-1 Drug Resistance between Recent and Chronic HIV-1 Infection within a Sub-Regional Cohort of Asian Patients

Background

The emergence and transmission of HIV-1 drug resistance (HIVDR) has raised concerns after rapid global antiretroviral therapy (ART) scale-up. There are limited data on the epidemiology of primary HIVDR in resource-limited settings in Asia. We aimed to determine the prevalence and compare the distribution of HIVDR in a cohort of ART-naïve Asian patients with recent and chronic HIV-1 infection.

Methods

Multicenter prospective study was conducted in ART-naïve patients between 2007 and 2010. Resistance-associated mutations (RAMs) were assessed using the World Health Organization 2009 list for surveillance of primary HIVDR.

Results

A total of 458 patients with recent and 1,340 patients with chronic HIV-1 infection were included in the analysis. The overall prevalence of primary HIVDR was 4.6%. Recently infected patients had a higher prevalence of primary HIVDR (6.1% vs. 4.0%, p = 0.065) and frequencies of RAMs to protease inhibitors (PIs; 3.9% vs. 1.0%, p<0.001). Among those with recent infection, the most common RAMs to nucleoside reverse transcriptase inhibitors (NRTIs) were M184I/V and T215D/E/F/I/S/Y (1.1%), to non-NRTIs was Y181C (1.3%), and to PIs was M46I (1.5%). Of patients with chronic infection, T215D/E/F/I/S/Y (0.8%; NRTI), Y181C (0.5%; non-NRTI), and M46I (0.4%; PI) were the most common RAMs. K70R (p = 0.016) and M46I (p = 0.026) were found more frequently among recently infected patients. In multivariate logistic regression analysis in patients with chronic infection, heterosexual contact as a risk factor for HIV-1 infection was less likely to be associated with primary HIVDR compared to other risk categories (odds ratio 0.34, 95% confidence interval 0.20–0.59, p<0.001).

Conclusions

The prevalence of primary HIVDR was higher among patients with recent than chronic HIV-1 infection in our cohort, but of borderline statistical significance. Chronically infected patients with non-heterosexual risks for HIV were more likely to have primary HIVDR.

Surveillance of transmitted HIV drug resistance in antiretroviral-naive patients aged less than 25 years, in Bangkok, Thailand

Emergence of transmitted HIV drug resistance (TDR) is a concern after global scale-up of antiretroviral therapy (ART). World Health Organization had developed threshold survey method for surveillance of TDR in resource-limited countries. ART in Thailand has been scaling up for >10 years. To evaluate the current TDR in Thailand, a cross-sectional study was conducted among antiretroviral-naive HIV-infected patients aged <25 years who newly visited infectious disease clinic in a university hospital, in 2011. HIV genotypic-resistance test was performed. World Health Organization 2009 surveillance drug-resistance mutations were used to define TDR. Of 50 patients, the prevalence of TDR was 4%. Of 2 patients with TDR, 1 had K103N and the other had Y181C mutations. Transmitted HIV drug resistance is emerging in Thailand after a decade of rapid scale-up of ART. Interventions to prevent TDR at the population level are essentially needed in Thailand. Surveillance for TDR in Thailand has to be regularly performed.

HIV-1 drug resistance-associated mutations among antiretroviral-naive Thai patients with chronic HIV-1 infection

Antiretroviral therapy (ART) has increased in resource-limited settings. This study determined the prevalence of HIV-1 drug resistance-associated mutations (DRAMs) among patients with chronic HIV-1 infections and compare DRAMs between CRF01_AE and B subtypes. ART-naive Thai patients who had ART initiation between 2010 and 2011 were enrolled prospectively. Genotypic assays were performed on viral reverse transcriptase and protease genes within 4 weeks before starting ART. DRAMs were assessed using the International AIDS Society-USA 2011 list. A total of 330 patients were included. HIV-1 subtypes included CRF01_AE (73%), B (23.9%), and others (3.1%). Median (IQR) CD4+ was 66 (23-172) cells/mm(3) and median (IQR) HIV-1 RNA was 5.2 (4.6-5.8) log copies/ml. The prevalence of patients with ≥1 DRAMs for any antiretroviral agents was 17.6%. DRAM prevalence was 17% for non-nucleoside reverse transcriptase inhibitors (NNRTIs), 0.6% for NRTIs, and 0.6% for protease inhibitors (PIs). DRAMs to NNRTIs were V106I (7%), V179D (4.2%), V179T (1.8%), E138A (1.5%), V90I (1.2%), K103N (0.9%), Y181C (0.9%), and P225H (0.3%). DRAMs to NRTIs were M184V (0.3%) and T215S (0.3%). The only major DRAM for PIs was M46L (0.6%). Minor DRAMs to PIs including I13V, M36I, H69K, and L89M were observed more frequently in CRF_01 AE. By multivariate analysis, the factors "HIV-1 subtype B" and "low pretreated CD4+ cell count" were associated with a higher rate of DRAMs. HIV-1 DRAMs, especially to NNRTIs, are emerging in a middle-income country after widespread use of NNRTI-based ART. HIV genotypic assays before ART initiation in patients with chronic HIV-1 infection should be considered.

Comparison of predicted susceptibility between genotype and virtual phenotype HIV drug resistance interpretation systems among treatment-naive HIV-infected patients in Asia: TASER-M cohort analysis

Background

Accurate interpretation of HIV drug resistance (HIVDR) testing is challenging, yet important for patient care. We compared genotyping interpretation, based on the Stanford University HIV Drug Resistance Database (Stanford HIVdb), and virtual phenotyping, based on the Janssen Diagnostics BVBA’s vircoTYPE™ HIV-1, and investigated their level of agreement in antiretroviral (ARV) naive patients in Asia, where non-B subtypes predominate.

Methods

Sequences from 1301 ARV-naive patients enrolled in the TREAT Asia Studies to Evaluate Resistance – Monitoring Study (TASER-M) were analysed by both interpreting systems. Interpretations from both Stanford HIVdb and vircoTYPE™ HIV-1 were initially grouped into 2 levels: susceptible and non-susceptible. Discrepancy was defined as a discordant result between the susceptible and non-susceptible interpretations from the two systems for the same ARV. Further analysis was performed when interpretations from both systems were categorised into 3 levels: susceptible, intermediate and resistant; whereby discrepancies could be categorised as major discrepancies and minor discrepancies. Major discrepancy was defined as having a susceptible result from one system and resistant from the other. Minor discrepancy corresponded to having an intermediate interpretation in one system, with a susceptible or resistant result in the other. The level of agreement was analysed using the prevalence adjusted bias adjusted kappa (PABAK).

Results

Overall, the agreement was high, with each ARV being in “almost perfect agreement”, using Landis and Koch’s categorisation. Highest discordance was observed for efavirenz (75/1301, 5.8%), all arising from susceptible Stanford HIVdb versus non-susceptible vircoTYPE™ HIV-1 predictions. Protease Inhibitors had highest level of concordance with PABAKs all above 0.99, followed by Nucleoside Reverse Transcriptase Inhibitors with PABAKs above 0.97 and non-NRTIs with the lowest PABAK of 0.88. The 68/75 patients with discordant efavirenz results harboured the V179D/E mutations compared to 7/1226 with no efavirenz discrepancy (p-value <0.001). In the 3-level comparison, all but one of the discrepancies was minor.

Conclusions

The two systems agreed well with lowest concordance observed for efavirenz. When interpreting HIVDR, especially in non-B subtypes, clinical correlation is crucial, in particular when efavirenz resistance is interpreted based on V179D/E.

Rates of emergence of HIV drug resistance in resource-limited settings: a systematic review

BACKGROUND

The increasing availability of antiretroviral therapy (ART) has improved survival and quality of life for many infected with HIV, but can also engender drug resistance. This review summarizes the available information on drug resistance in adults in resource-limited settings.

METHODS

The online databases PubMed and Google Scholar, pertinent conference abstracts and references from relevant articles were searched for publications available before November 2011. Data collected after ART rollout were reviewed.

RESULTS

A total of 7 studies fulfilled the criteria for the analysis of acquired drug resistance and 22 fulfilled the criteria for the analysis of transmitted drug resistance (TDR). Acquired resistance was detected in 7.2% of patients on ART for 6-11 months, 11.1% at 12-23 months, 15.0% at 24-35 months, and 20.7% at ≥ 36 months. Multi-class drug resistance increased steadily with time on ART. The overall rate of TDR in all resource-limited countries studied was 6.6% (469/7,063). Patients in countries in which ART had been available for ≥ 5 years were 1.7 × more likely to have TDR than those living in a country where ART had been available for <5 years (P<0.001). The reported prevalence of TDR was 5.7% (233/4,069) in Africa, 7.6% (160/2,094) in Asia and 8.4% (76/900) in Brazil.

CONCLUSIONS

The emergence of drug resistance following access to ART in resource-limited settings resembles what was seen in resource-rich countries and highlights the need for virological monitoring for drug failure, drug resistance testing and alternative drug regimens that have proven beneficial in these resource-rich settings.

The 15th Bangkok International Symposium on HIV Medicine

This year, more than 700 participants attended this symposium, which is organized annually by the HIV Netherlands, Australia, Thailand Research Collaboration (HIV-NAT) to provide a comprehensive update on issues related to both adult and pediatric HIV regionally and globally. It comprises plenary sessions, parallel workshops including cases with e-voting, and a popular and entertaining debate. This year, plenary sessions included topics such as Treatment 2.0, HIV eradication, resistance testing in Asia, pre-antiretroviral therapy care, complications in children, TB, acute HIV, HIV and aging and new antiretroviral therapies. This article summarizes some of the particularly relevant plenary sessions.

HIV-1 drug resistance in antiretroviral-naive individuals with HIV-1-associated tuberculous meningitis initiating antiretroviral therapy in Vietnam

BACKGROUND

Access to antiretroviral therapy (ART) for HIV-infected individuals in Vietnam is rapidly expanding, but there are limited data on HIV drug resistance (HIVDR) to guide ART strategies.

METHODS

We retrospectively conducted HIVDR testing in 220 ART-naive individuals recruited to a randomized controlled trial of immediate versus deferred ART in individuals with HIV-associated tuberculous meningitis in Ho Chi Minh City (HCMC) from 2005-2008. HIVDR mutations were identified by population sequencing of the HIV pol gene and were defined based on 2009 WHO surveillance drug resistance mutations (SDRMs).

RESULTS

We successfully sequenced 219/220 plasma samples of subjects prior to ART; 218 were subtype CRF01_AE and 1 was subtype B. SDRMs were identified in 14/219 (6.4%) subjects; 8/14 were resistant to nucleoside/nucleotide reverse transcriptase inhibitors (NRTIs; T69D, L74V, V75M, M184V/I and K219R), 5/14 to non-nucleoside reverse transcriptase inhibitors (NNRTIs; K103N, V106M, Y181C, Y188C and G190A), 1/14 to both NRTIs and NNRTIs (D67N and Y181C) and none to protease inhibitors. After 6 months of ART, eight subjects developed protocol-defined virological failure. HIVDR mutations were identified in 5/8 subjects. All five had mutations with high-level resistance to NNRTIs and three had mutations with high-level resistance to NRTIs. Due to a high early mortality rate (58%), the effect of pre-existing HIVDR mutations on treatment outcome could not be accurately assessed.

CONCLUSIONS

The prevalence of WHO SDRMs in ART-naive individuals with HIV-associated tuberculous meningitis in HCMC from 2005-2008 is 6.4%. The SDRMs identified conferred resistance to NRTIs and/or NNRTIs, reflecting the standard first-line ART regimens in Vietnam.

Low prevalence of transmitted drug resistance in patients newly diagnosed with HIV-1 infection in Sweden 2003-2010

Transmitted drug resistance (TDR) is a clinical and epidemiological problem because it may contribute to failure of antiretroviral treatment. The prevalence of TDR varies geographically, and its prevalence in Sweden during the last decade has not been reported. Plasma samples from 1,463 patients newly diagnosed with HIV-1 infection between 2003 and 2010, representing 44% of all patients diagnosed in Sweden during this period, were analyzed using the WHO 2009 list of mutations for surveillance of TDR. Maximum likelihood phylogenetic analyses were used to determine genetic subtype and to investigate the relatedness of the sequences. Eighty-two patients showed evidence of TDR, representing a prevalence of 5.6% (95% CI: 4.5%–6.9%) without any significant time trends or differences between patients infected in Sweden or abroad. Multivariable logistic regression showed that TDR was positively associated with men who have sex with men (MSM) and subtype B infection and negatively associated with CD4 cell counts. Among patients with TDR, 54 (68%) had single resistance mutations, whereas five patients had multi-drug resistant HIV-1. Phylogenetic analyses identified nine significantly supported clusters involving 29 of the patients with TDR, including 23 of 42 (55%) of the patients with TDR acquired in Sweden. One cluster contained 18 viruses with a M41L resistance mutation, which had spread among MSM in Stockholm over a period of at least 16 years (1994–2010). Another cluster, which contained the five multidrug resistant viruses, also involved MSM from Stockholm. The prevalence of TDR in Sweden 2003–2010 was lower than in many other European countries. TDR was concentrated among MSM, where clustering of TDR strains was observed, which highlights the need for continued and improved measures for targeted interventions.

Prevalence of HIV Drug Resistance Mutations in HIV Type 1 Isolates in Antiretroviral Therapy Naïve Population from Northern India

Objective. The increased use of antiretroviral therapy (ART) has reduced the morbidity and mortality associated with HIV, adversely leading to the emergence of HIV drug resistance (HIVDR). In this study we aim to evaluate the prevalence of HIVDR mutations in ART-naive HIV-1 infected patients from northern India. Design. Analysis was performed using Viroseq genotyping system based on sequencing of entire protease and two-thirds of the Reverse Transcriptase (RT) region of pol gene. Results. Seventy three chronic HIV-1 infected ART naïve patients eligible for first line ART were enrolled from April 2006 to August 2008. In 68 patients DNA was successfully amplified and sequencing was done. 97% of HIV-1 strains belonged to subtype C, and one each to subtype A1 and subtype B. The overall prevalence of primary DRMs was 2.9% [2/68, 95% confidence interval (CI), 0.3%–10.2%]. One patient had a major RT mutation M184V, known to confer resistance to lamivudine, and another had a major protease inhibitor (PI) mutation D30N that imparts resistance to nelfinavir. Conclusion. Our study shows that primary HIVDR mutations have a prevalence of 2.9% among ART-naive chronic HIV-1 infected individuals.

Emergence of HIV-1 drug resistance mutations among antiretroviral-naïve HIV-1-infected patients after rapid scaling up of antiretroviral therapy in Thailand

Background

After rapid scaling up of antiretroviral therapy in HIV-1-infected patients, the data of primary HIV-1 drug resistance in Thailand is still limited. This study aims to determine the prevalence and associated factors of primary HIV-1 drug resistance in Thailand.

Methods

A prospective observational study was conducted among antiretroviral-naïve HIV-1-infected Thai patients from 2007 to 2010. HIV-1 subtypes and mutations were assayed by sequencing a region of HIV-1 pol gene. Surveillance drug resistance mutations recommended by the World Health Organization for surveillance of transmitted HIV-1 drug resistance in 2009 were used in all analyses. Primary HIV-1 drug resistance was defined as the presence of one or more surveillance drug resistance mutations.

Results

Of 466 patients with a mean age of 38.8 years, 58.6% were males. Risks of HIV-1 infection included heterosexual (77.7%), homosexual (16.7%), and intravenous drug use (5.6%). Median (IQR) CD4 cell count and HIV-1 RNA were 176 (42-317) cells/mm³ and 68,600 (19,515-220,330) copies/mL, respectively. HIV-1 subtypes were CRF01_AE (86.9%), B (8.6) and other recombinants (4.5%). The prevalence of primary HIV-1 drug resistance was 4.9%; most of these (73.9%) had surveillance drug resistance mutations to only one class of antiretroviral drugs. The prevalence of patients with NRTI, NNRTI, and PI surveillance drug resistance mutations was 1.9%, 2.8% and 1.7%, respectively. From logistic regression analysis, there was no factor significantly associated with primary HIV-1 drug resistance. There was a trend toward higher prevalence in females [odds ratio 2.18; 95% confidence interval 0.896-5.304; p = 0.086].

Conclusions

There is a significant emergence of primary HIV-1 drug resistance in Thailand after rapid scaling up of antiretroviral therapy. Although HIV-1 genotyping prior to antiretroviral therapy initiation is not routinely recommended in Thailand, our results raise concerns about the risk of early treatment failure in patients with primary HIV-1 drug resistance. Interventions to prevent the transmission of HIV-1 drug resistance and continuation of surveillance for primary HIV-1 drug resistance in Thailand are indicated.

The potential impact of an HIV vaccine with limited protection on HIV incidence in Thailand: a modeling study

BACKGROUND

The RV144 trial on the ALVAC/AIDSVAX candidate HIV vaccine, carried out in Thailand, showed short-lived protection against infection.

METHODS

Using a deterministic compartmental model we explored the potential impact of this vaccine on heterosexual HIV transmission in Thailand. Both one-off vaccination strategies, as well as strategies with regular boosting, either annually or every two years, were explored. Both targeting the general adult population and prioritizing sex workers were modeled. The impact of risk compensation among high risk groups, as well as whether higher levels of safe sex in high risk groups could be an alternative to vaccination, was studied.

RESULTS

One-off vaccination campaigns had only transient effects, and boosting appears to be a key component of successful vaccination campaigns. Intensive vaccination campaigns may reduce HIV incidence by up to 75% after 10 years of vaccination. Targeting only sex workers has a smaller impact but has a more favorable cost-benefit ratio. Risk compensation has the potential of undoing much of the benefits of a vaccination program and may even increase incidence. In contrast, higher levels of safe sex among sex workers would provide a viable alternative to vaccinating this group.

DISCUSSION

The new vaccine holds promise for controlling HIV in Thailand and similar countries. In view of the short lived protection of the vaccine, regular boosting of immunity as well as avoidance of risk compensation are essential. Targeting sex workers would achieve the greatest reduction in incidence per vaccination and may be considered for expensive vaccines but its cost-effectiveness has to be compared to alternatives.