One of the goals of UNAIDS, is that 95% of HIV infected persons on treatment should attain viral suppression by 2030. On the evidence that treatment is prevention, South Africa in 2016 implemented the ‘Universal Test and Treat’ (UTT) approach in the management of HIV infections. Having a greater understanding of the potential challenges to viral suppression is crucial for the design of interventions to enhance viral suppression.
A study funded by the South African Medical Research Council (SAMRC) and National Research Foundation, led by Prof Pascal Bessong, Unit Director of the SAMRC’s Antimicrobial Resistance and Global Health Research Unit was published in the journal of AIDS Research and Therapy - which aimed to review current data on factors that could negatively impact the attainment of viral suppression in South Africa.
Study findings
- The level of drug resistance in persons who have not entered an HIV treatment programme has increased over time.
- There is a moderate level of drug resistance (between 5 and 15%) in the treatment inexperienced population in at least one community in 8 of the 9 provinces in South Africa.
- The concurrent use of antiretrovirals (ARVs) and alternative medicines to treat HIV is fairly common and may be impacting negatively on treatment adherence.
- Data is scarce on the relationship between the genetically diverse South African population and the metabolism of ARVs. Data for the analysis was drawn from publicly available datasets.
- Fewer datasets on drug resistance in the untreated population were available from Mpumalanga and Northern Cape Provinces.
- There are several communities in South Africa from which people with HIV may not benefit from the standard treatment regimen, because the virus they carry is resistant to components of the treatment regimen.
- HIV drug resistance in the untreated population is not negligible; and is relatively high in some communities.
- The increasing levels of drug resistant viruses in the untreated population poses a threat to viral load suppression and the sustainability of first line regimens.
- To facilitate achieving the viral suppression targets in 95% of those on treatment, a combination of interventions may be required.
On the study findings, Prof Bessong said that there is limited data to guide our understanding on the relationship between host genetics of the ethnically diverse South African population and pharmacokinetics and pharmacodynamics of ARVs, and how these impacts viral suppression in the era of ‘UTT’. He added that ARV therapy suppresses viral replication and reduces the chance of viral transmission.
“In this light, treatment is prevention, but treatment can be prevention if and only if adequate viral suppression is achieved. Individuals initiating treatment with drug resistant viruses may not attain adequate viral suppression. Consequently, research is required to unravel avenues through which people who have not been initiated into HIV treatment programmes contract drug resistant viruses, other than contracting the resistant viruses from other people. Outcomes from this type of research will provide insights for intervention. The findings of this study challenge the assumption that drug resistance in those initiating antiretroviral therapy is negligible” concluded Prof Bessong.
Areas for further investigation includes research on the possible avenues of exposure to ARVs outside of HIV treatment, prior to HIV treatment initiation as well as research to define exactly what is transmitted drug resistance.
Optimal management of the different drivers of HIV drug resistance in the untreated population will be beneficial in ensuring sustained viral suppression in at least 95% of those on treatment, a key goal of the UNAIDS 95-95-95 strategy.