Presence of HIV drug resistance in antiretroviral therapy-naive and -experienced patients from Papua New Guinea.

OBJECTIVES: The optimal benefits of antiretroviral therapy (ART) can be compromised by the emergence of HIV drug resistance (HIVDR) resulting in treatment failure. ART was introduced in Papua New Guinea (PNG) in 2004, yet biological data on HIVDR are lacking. The aim of the study was to investigate levels of HIVDR in ART-naive and -experienced patients in PNG. METHODS: We recruited, interviewed and collected blood from 108 ART-naive and 102 ART-experienced patients from two Highlands provinces of PNG. Dried blood spots were tested for HIVDR from all patients with detectable plasma viral load of ≥200 copies/mL using established in-house assays. RESULTS: The PCR amplification success was 90.6% (n = 96) and 66.7% (n = 12) using dried blood spots from ART-naive and -experienced patients, respectively. Transmitted drug resistance was detected in 2.1% (n = 2) of samples from ART-naive patients; acquired drug resistance was detected in 50% (n = 6) of samples from ART-experienced individuals. CONCLUSIONS: Our data showed that transmitted drug resistance in PNG is low and acquired drug resistance is higher with 12.7% of the ART-experienced patients failing treatment. As ART access is rapidly expanding in PNG, monitoring of drug resistance is paramount for early detection of treatment failure.

Factors Influencing Antiretroviral Adherence and Virological Outcomes in People Living with HIV in the Highlands of Papua New Guinea.

Adherence to antiretroviral therapy (ART) is paramount for virological suppression and positive treatment outcomes. ART has been rapidly scaled up in Papua New Guinea (PNG) in recent years, however clinical monitoring of HIV+ individuals on ART is limited. A cross-sectional study was conducted at two major sexual health clinics in high HIV prevalence provinces in the Highlands Region of PNG to assess ART adherence, factors affecting adherence and the relationship between ART adherence and virological outcomes. Ninety-five HIV+ individuals were recruited and administered a questionnaire to gather demographic and ART adherence information whilst clinical data and pill counts were extracted from patient charts and blood was collected for viral load testing. Bivariate analysis was performed to identify independent predictors of ART adherence. Fourteen percent (n = 12) of participants showed evidence of virological failure. Although the majority of participants self-reported excellent ART adherence in the last seven days (78.9%, 75/91), pill count measurements indicated only 40% (34/84) with >95% adherence in the last month. Taking other medications while on ART (p = 0.01) and taking ART for ≥1 year (p = 0.037) were positively associated with adherence by self-report and pill count, respectively. Participants who had never heard of drug resistance were more likely to show virological failure (p = 0.033). Misconception on routes of HIV transmission still persists in the studied population. These findings indicate that non-adherence to ART is high in this region of PNG and continued education and strategies to improve adherence are required to ensure the efficacy of ART and prevent HIV drug resistance.