Short communication: Prevalence of HIV-1 transmitted drug resistance in Liberia

Prevalence of drug resistance mutations among ART-naive and -experienced HIV-infected patients in Sierra Leone

Objectives

The aim of this study was to assess the prevalence of HIV drug resistance (HIVDR) in HIV-infected ART-naive and -experienced patients in Sierra Leone.

Patients and methods

We conducted a cross-sectional study of HIV-positive adults aged ≥18 years at Connaught Hospital in Freetown, Sierra Leone in November 2017. Sequencing was performed in the reverse transcriptase, protease and integrase regions, and interpreted using the Stanford HIVDR database and WHO 2009 mutation list.

Results

Two hundred and fifteen HIV-infected patients were included (64 ART naive and 151 ART experienced). The majority (66%) were female, the median age was 36 years and the median ART exposure was 48 months. The majority (83%) were infected with HIV-1 subtype CRF02_AG. In the ART-naive group, the pretreatment drug resistance (PDR) prevalence was 36.7% (14.2% to NRTIs and 22.4% to NNRTIs). The most prevalent PDR mutations were K103N (14.3%), M184V (8.2%) and Y181C (4.1%). In the ART-experienced group, 64.4% harboured resistance-associated mutations (RAMs) and the overall prevalence of RAMs to NRTIs and NNRTIs was 85.2% (52/61) and 96.7% (59/61), respectively. The most prevalent RAMs were K103N (40.7%), M184V (28.8%), D67N (15.3%) and T215I/F/Y (15.3%). Based on the genotypic susceptibility score estimates, 22.4% of ART-naive patients and 56% of ART-experienced patients were not susceptible to first-line ART used in Sierra Leone.

Conclusions

A high prevalence of circulating NRTI- and NNRTI-resistant variants was observed in ART-naive and -experienced HIV-1-infected patients in Sierra Leone. This necessitates the implementation of HIVDR surveillance programmes to inform national ART guidelines for the treatment and monitoring of HIV-infected patients in Sierra Leone.

Prevalence of pretreatment and acquired HIV-1 mutations associated with resistance to lamivudine or rilpivirine: a systematic review

BACKGROUND

Pretreatment and acquired drug resistance mutations (DRMs) can limit antiretroviral therapy effectiveness.

METHODS

We review prevalence of DRMs with resistance to nucleoside reverse transcriptase inhibitors (NRTIs) and non-nucleoside reverse transcriptase inhibitors (NNRTIs), focusing on lamivudine and rilpivirine, from 127 articles with >100,000 individuals with HIV-1 infection.

RESULTS

Estimated global prevalence of pretreatment resistance to any NRTI was 4% and to any NNRTI was 6%. Most prevalent DRMs resistant to lamivudine or rilpivirine were at positions E138 (4%), V179 (1%) and M184 (1%). Estimated acquired DRM prevalence was 58% for any NRTIs and 67% for any NNRTIs, most frequently at positions M184 (58%) and Y181 (21%).

CONCLUSIONS

This review suggests low risk of lamivudine- or rilpivirine-resistant mutations in treatment-naive, HIV-1-infected individuals.

Surveillance of transmitted HIV-1 antiretroviral drug resistance in the context of decentralized HIV care in Senegal and the Ebola outbreak in Guinea

Objectives

Disruption in HIV care provision may enhance the development and spread of drug resistance due to inadequate antiretroviral therapy. This study thus determined the prevalence of HIV-1 transmitted drug resistance (TDR) in settings of decentralized therapy and care in Senegal and, the Ebola outbreak in Guinea. Antiretroviral-naïve patients were enrolled following a modified WHO TDR Threshold Survey method, implemented in Senegal (January–March 2015) and Guinea (August–September 2015). Plasma and dried blood spots specimens, respectively from Senegalese (n = 69) and Guinean (n = 50) patients, were collected for direct sequencing of HIV-1 pol genes. The Stanford Calibrated Population Resistance program v6.0 was used for Surveillance Drug Resistance Mutations (SDRMs).

Results

Genotyping was successful from 54/69 (78.2%) and 31/50 (62.0%) isolates. In Senegal, TDR prevalence was 0% (mean duration since HIV diagnosis 4.08 ± 3.53 years). In Guinea, two patients exhibited SDRMs M184V (NRTI), T215F (TAM) and, G190A (NNRTI), respectively. TDR prevalence at this second site, however, could not be ascertained because of low sample size. Phylogenetic inference confirmed CRF02_AG predominance in Senegal (62.96%) and Guinea (77.42%). TDR prevalence in Senegal remains extremely low suggesting improved control measures. Continuous surveillance in both settings is mandatory and, should be done closest to diagnosis/transmission time and with larger sample size.

Likely effect of the 2014 Ebola epidemic on HIV care in Liberia

OBJECTIVE

Liberia's health system has been severely struck by the 2014 Ebola epidemic. We aimed to assess the potential effect of this epidemic on the care of HIV patient in two clinics [John F. Kennedy (JFK) and Redemption Hospitals] in Monrovia, which stayed open throughout the epidemic.

DESIGN AND METHODS

A preexisting electronic database of HIV patient's follow-up visits was used to estimate three weekly parameters from January 2012 to October 2014: number of visits, number of new patient, and proportion of patients with follow-up delay. We used segmented negative binomial regressions to assess trends before and after the week of the Ebola outbreak defined in June 2014 by WHO.

RESULTS

The cumulative number of patients in care comprised 5948 patients with a total of 56 287 visits between January 2012 and October 2014. From June 2014, the number of visit per week, stable since 2012, abruptly decreased (59%) in Redemption (P < 0.001) and progressively decreased by 3% per week in JFK (P < 0.001). In both the clinics, the weekly proportion of patient with follow-up delay sharply increased after the point break from June 2014 (P value < 0.001). From June 2014, a significant decrease in new patients per week occurred in both the clinics: by 57% (P value < 0.001) in Redemption and by 4.6% per week (P value < 0.001) in JFK.

CONCLUSION

The Ebola epidemic had a significant effect on HIV care in Monrovia. Given the particular impact on the rate of patients with follow-up delay, a long-term impact is feared.

Substituted Bis-THF Protease Inhibitors with Improved Potency against Highly Resistant Mature HIV-1 Protease PR20

An extremely drug resistant mutant of HIV-1 protease (PR) bearing 20 mutations (PR20) has been studied with two potent antiviral investigational inhibitors. GRL-5010A and GRL-4410A were designed to introduce hydrogen bond interactions with the flexible flaps of the PR by incorporating gem-difluorines and alkoxy, respectively, at the C4 position of the bis-THF of darunavir. PR20 provides an excellent model for high level resistance, since clinical inhibitors are >1000-fold less active on PR20 than on wild-type enzyme. GRL-5010A and GRL-4410A show inhibition constants of 4.3 ± 7.0 and 1.7 ± 1.8 nM, respectively, for PR20, compared to the binding affinity of 41 ± 1 nM measured for darunavir. Crystal structures of PR20 in complexes with the two inhibitors confirmed the new hydrogen bond interactions with Gly 48 in the flap of the enzyme. The two new compounds are more effective than darunavir in inhibiting mature PR20 and show promise for further development of antiviral agents targeting highly resistant PR mutants.

Prevalence of HIV-1 drug resistance among patients failing first-line ART in Monrovia, Liberia: a cross-sectional study

OBJECTIVES

To assess the prevalence of acquired drug resistance in HIV-1-infected patients living in Monrovia, Liberia, who had clinical and/or immunological failure of first-line ART according to WHO criteria.

PATIENTS AND METHODS

Patients receiving ART for >1 year with clinical and/or immunological failure were included. Sequencing of protease and reverse transcriptase regions was performed using Agence Nationale de Recherche sur le SIDA et les hépatites virales (ANRS) procedures and sequences were interpreted using the ANRS resistance algorithm.

RESULTS

Ninety patients were enrolled. They had been receiving ART for a median time of 42 months and half were receiving zidovudine/lamivudine/nevirapine. Seventy-five per cent of patients were infected with CRF02_AG. Twenty-seven per cent of patients displayed a plasma viral load <50 copies/mL. Among the 66 patients with detectable viraemia, the median viral load was 4.7 log10 copies/mL (IQR = 3.0-5.6). The prevalence of NRTI and NNRTI resistance-associated mutations (RAMs) was 63% and 71%, respectively; and the median number of NRTI and NNRTI RAMs was 2 and 3, respectively. Two patients (4%) displayed viruses with PI RAMs. Regarding NRTI drug resistance, 29%, 38%, 63%, 29% and 25% of patients had viruses resistant to zidovudine, stavudine, lamivudine/emtricitabine, abacavir and tenofovir, respectively. Regarding the NNRTI drug class, 56%, 65%, 33% and 42% of patients had viruses resistant to efavirenz, nevirapine, etravirine and rilpivirine, respectively.

CONCLUSIONS

The high prevalence of acquired drug resistance in patients followed in two centres of the Liberian capital city, documented after a median of 3 years on a first-line ART regimen, jeopardizes the activity of second-line regimens and highlights the need for virological monitoring in these settings.