Rational design, synthesis and biological evaluation of novel HIV-1 protease inhibitors containing 2-phenylacetamide derivatives as P2 ligands with potent activity against DRV-Resistant HIV-1 variants

A novel kind of potent HIV-1 protease inhibitors, containing diverse hydroxyphenylacetic acids as the P2-ligands and 4-substituted phenyl sulfonamides as the P2' ligands, were designed, synthesized and evaluated in this work. Majority of the target compounds exhibited good to excellent activity against HIV-1 protease with IC50 values below 200 nM. In particular, compound 18d with a 2-(3,4-dihydroxyphenyl) acetamide as the P2 ligand and a 4- methoxybenzene sulfonamide P2' ligand exhibited inhibitory activity IC50 value of 0.54 nM, which was better than that of the positive control darunavir (DRV). More importantly, no significant decline of the potency against HIV-1DRVRS (DRV-resistant mutation) and HIV-1NL4_3 variant (wild type) for 18d was detected. The molecular docking study of 18d with HIV-1 protease (PDB-ID: 1T3R, www.rcsb.org) revealed possible binding mode with the HIV-1 protease. These results suggested the validity of introducing phenol-derived moieties into the P2 ligand and deserve further optimization which was of great value for future discovery of novel HIV-1 protease.

Utilization of dried blood spot specimens can expedite nationwide surveillance of HIV drug resistance in resource-limited settings

INTRODUCTION

Surveillance of HIV drug resistance (HIVDR) is crucial to ensuring the continued success of antiretroviral therapy (ART) programs. With the concern of reduced genotyping sensitivity of HIV on dried blood spots (DBS), DBS for HIVDR surveillance have been limited to ART-naïve populations. To investigate if DBS under certain conditions may also be a feasible sample type for HIVDR testing in ART patients, we piloted nationwide surveys for HIVDR among ART patients using DBS in two African countries with rapid scale-up of ART.

METHODS

EDTA-venous blood was collected to prepare DBS from adult and pediatric ART patients receiving treatment during the previous 12-36 months. DBS were stored at ambient temperature for two weeks and then at -80°C until shipment at ambient temperature to the WHO-designated Specialized HIVDR Laboratory at CDC in Atlanta. Viral load (VL) was determined using NucliSENS EasyQ® HIV-1 v2.0 kits; HIVDR genotyping was performed using the ATCC HIV-1 Drug Resistance Genotyping kits.

RESULTS

DBS were collected from 1,368 and 1,202 ART patients; 244 and 255 these specimens had VL ≥1,000 copies/mL in Kenya and Tanzania, respectively. The overall genotyping rate of those DBS with VL ≥1,000 copies/mL was 93.0% (95% CI: 89.1%-95.6%) in Kenya and 91.8% (87.7%-94.6%) in Tanzania. The turnaround times for the HIVDR surveys from the time of collecting DBS to completing laboratory testing were 6.5 months and 9.3 months for the Kenya and Tanzania surveys, respectively.

CONCLUSIONS

The study demonstrates a favorable outcome of using DBS for nationwide surveillance of HIVDR in ART patients. Our results confirm that DBS collected and stored at ambient temperature for two weeks, and shipped with routine courier services are a reliable sample type for large-scale surveillance of acquired HIVDR.

Results from implementing updated 2012 World Health Organization Guidance on early-warning indicators of HIV drug resistance in Zimbabwe

Objective

This study evaluated the performance of sentinel sites in preventing the emergence of HIVDR using Early Warning Indicators (HIVDR EWI) survey.

Methods

Adult and paediatric patient data on: On time pill pick up, Retention in care, Pharmacy stock-outs, and Dispensing practices was collected. Information from pharmacy registers was verified using facility-held cards. This was a cross-sectional analysis of retrospectively collected data from 72 sites providing both adult and paediatric ART as well as two providing adult ART only. All data were entered into and analysed using a WHO EWI data abstraction electronic tool.

Results

Twenty-one percent of sites providing adult and 4.2% of sites providing paediatric ART managed to meet the target for on time pill pick up. Retention in care indicator was met by 48.7% (95% CI: 36.9-60.6) of sites. ARV stock-outs occurred in 81.1% (95% CI: 70-89.3) adult sites and 63.9% (95% CI: 50-78.6) paediatric sites. ARVs were appropriately dispensed by 86.5% (95% CI: 75.6-93.3) of adult sites and 84.7% (95% CI: 74.3-92.1) of paediatric sites.

Conclusions

Most sites had low performance in many indicators in this survey and failed to meet the recommended targets. Some policies such as the current buffer stock and storage outside Harare should be revised in order to improve site access to ARVs. The country should prioritize the provision of viral load testing services in all provinces. The electronic patient management system should be rolled out to all ART sites to improve patient tracking and monitoring by sites.

Drug resistance mutations and genetic diversity in adults treated for HIV type 1 infection in Mauritania

The aim of this cross-sectional study was to evaluate the drug resistance mutationprofile observed in patients receiving antiretroviral therapy with virological failure and to document the HIV-1 genetic diversity in Mauritania. Eighty-six subjects were included and 65 samples were amplified successfully and sequenced. HIV-1 genotyping was performed using the Agence Nationale de Recherche sur le SIDA AC11 resistance procedure. The median treatment duration was 32 months (range: 6-88) and the median viral load, 5 log10 copies/ml (range: 3.13-7). Fifty-nine patients (90.8%) were on first line regimens including 32.0% (19/59) on triomune fixed-dose and six on second-line therapy with NonNucleoside Reverse Transcriptase plus a protease inhibitor. Forty-seven patients (72.3%) had at least one drug resistance mutation including 73.0% (43/59) on first-line therapy. For the second-line, one out of six patients presented resistance mutations and only one presented PI DRM. Overall, the most common DRMs detected were M184V/I (n = 32; 49.2%), K103N (n = 28; 43%), and Y181C (n = 13; 20%). Thymidine Analog Mutations (TAMs) were found in 26.0% (n = 17) of strains and the most common was T215Y (n = 11, 16.9%). Phylogenetic analysis revealed 17 HIV-1 variants with the predominance of CRF02_AG (n = 42; 64.6%). A high rate of DRM was found in this study and shows the potential need for a structured virological surveillance including viral load quantification and genotyping. Further studies may also be needed in regards to the great variability of HIV-1 strains in Mauritania.

HIV drug resistance early warning indicators in Namibia for public health action

Background

HIV drug resistance (HIVDR) testing is not routinely available in many resource-limited settings, therefore antiretroviral therapy (ART) program and site factors known to be associated with emergence of HIVDR should be monitored to optimize the quality of patient care and minimize the emergence of preventable HIVDR.

Methods

In 2010, Namibia selected five World Health Organization Early Warning Indicators (EWIs) and scaled-up monitoring from 9 to 33 ART sites: ART prescribing practices, Patients lost to follow-up (LTFU) at 12 months, Patients switched to a second-line regimen at 12 months, On-time antiretroviral (ARV) drug pick-up, and ARV drug-supply continuity.

Results

Records allowed reporting on three of the five selected EWIs. 22 of 33 (67%) sites met the target of 100% initiated on appropriate first-line regimens. 17 of 33 (52%) sites met the target of ≤20% LTFU. 15 of 33 (45%) sites met the target of 0% switched to a second-line regimen.

Conclusions

EWI monitoring directly resulted in public health action which will optimize the quality of care, specifically the strengthening of ART record systems, engagement of ART sites, and operational research for improved adherence assessment and ART patient defaulter tracing.

Update on World Health Organization HIV drug resistance prevention and assessment strategy: 2004-2011

The HIV drug resistance (HIVDR) prevention and assessment strategy, developed by the World Health Organization (WHO) in partnership with HIVResNet, includes monitoring of HIVDR early warning indicators, surveys to assess acquired and transmitted HIVDR, and development of an accredited HIVDR genotyping laboratory network to support survey implementation in resource-limited settings. As of June 2011, 52 countries had implemented at least 1 element of the strategy, and 27 laboratories had been accredited. As access to antiretrovirals expands under the WHO/Joint United Nations Programme on HIV/AIDS Treatment 2.0 initiative, it is essential to strengthen HIVDR surveillance efforts in the face of increasing concern about HIVDR emergence and transmission.

HIV drug resistance early warning indicators in cohorts of individuals starting antiretroviral therapy between 2004 and 2009: World Health Organization global report from 50 countries

The World Health Organization developed a set of human immunodeficiency virus drug resistance (HIVDR) early warning indicators (EWIs) to assess antiretroviral therapy clinic and program factors associated with HIVDR. EWIs are monitored by abstracting data routinely recorded in clinical records, and the results enable clinics and program managers to identify problems that should be addressed to minimize preventable emergence of HIVDR in clinic populations. As of June 2011, 50 countries monitored EWIs, covering 131 686 patients initiating antiretroviral treatment between 2004 and 2009 at 2107 clinics. HIVDR prevention is associated with patient care (appropriate prescribing and patient monitoring), patient behavior (adherence), and clinic/program management efforts to reduce treatment interruptions (follow up, retention on first-line ART, procurement and supply management of antiretroviral drugs). EWIs measure these factors and the results have been used to optimize patient and population treatment outcomes.

Monitoring of early warning indicators for HIV drug resistance in antiretroviral therapy clinics in Zimbabwe

Monitoring human immunodeficiency virus drug resistance (HIVDR) early warning indicators (EWIs) can help national antiretroviral treatment (ART) programs to identify clinic factors associated with HIVDR emergence and provide evidence to support national program and clinic-level adjustments, if necessary. World Health Organization-recommended HIVDR EWIs were monitored in Zimbabwe using routinely available data at selected ART clinics between 2007 and 2009. As Zimbabwe's national ART coverage increases, improved ART information systems are required to strengthen routine national ART monitoring and evaluation and facilitate scale-up of HIVDR EWI monitoring. Attention should be paid to minimizing loss to follow-up, supporting adherence, and ensuring clinic-level drug supply continuity.

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.