Monitoring for treatment failure in patients on first-line antiretroviral treatment in resource-constrained settings

Purpose of review The number of people living with HIV in low-income and middle-income countries (LMICs), who will fail first-line treatment and benefit from regimen switching, will steadily increase in the coming years. The diagnosis of treatment failure in many settings is challenging because of limited access to plasma HIV RNA testing. This article summarizes recent studies in LMICs, investigating the diagnosis of treatment failure. Recent findings WHO recommended clinico-immunological criteria to identify first-line treatment failure, which have a low sensitivity and positive predictive value. The addition of adherence criteria or alternative clinical and laboratory markers improves performance, but overall the results are suboptimal. This situation leads to both delayed and inappropriately premature switching to more expensive second-line agents. The cost-effectiveness of alternative monitoring strategies is debated, but there is increasing interest in the use of viral load testing to confirm virological failure before switching to second-line therapy. However, access to viral load testing in LMICs remains limited and a simple point-of-care assay is not yet available. Summary Monitoring the efficacy of antiretroviral therapy in LMICs remains a critical challenge. Current research priorities include the development of simpler, cheaper assays and optimizing monitoring strategies based on currently available technologies.