Undetectable: How Viral Load Monitoring Can Improve HIV Treatment in Developing Countries

With more than eight million individuals worldwide now receiving antiretroviral therapy (ART), the ability to monitor and optimise treatment effectiveness is key to the success of HIV treatment programmes.

Viral load testing – measuring the number of copies of HIV in the blood – is the only way to accurately assess the level of viral replication in HIV-positive patients. Routine monitoring of viral load will help to reinforce a patient’s adherence to ART alongside counselling and support, thereby ensuring viral suppression and preventing treatment failure before it occurs. Routine testing also ensures that health-care workers can diagnose treatment failure early on when drug resistance occurs, and appropriately switch patients from first-line ART to more effective second-line treatment regimens. With large numbers of patients in Africa already having been on treatment for several years, ensuring patients can access viral load testing is emerging as a global priority. Furthermore, for treatment as prevention to be successful, viral load monitoring will be a critical component.

For patients on ART, the World Health Organization (WHO) recommends viral load testing twice yearly in settings where testing is available. Unfortunately, viral load testing remains largely unavailable in resource-limited settings, in which the majority of HIV-positive patients reside. Instead of being an important routine monitoring and patient support tool in these contexts – as it is in resource-rich countries – viral load testing is rarely available, and where it is, its use is limited to confirming treatment failure. The result is avoidable morbidity and mortality among patients, and the potential transmission of drug-resistant forms of the virus.

It is critical, therefore, that access to viral load testing in resource-limited settings is prioritised as part of the next phase in the fight against HIV/AIDS. Poor access to viral load testing to date is a result of current test complexity, requiring specialised laboratory facilities. The majority of HIV-positive patients globally live in remote settings served by district- level laboratories that may be without reliable access to a power supply or highly trained staff, and where transport of samples to central reference laboratories causes delays. Poor access is also due to the fact that tests are costly. A lack of market competition to date means prices remain high. Ultimately, viral load testing prices will have to come down, as well as the cost of second- and third-line ART. Simple tests that can be performed at a community-based level using district laboratories, and/or a point-of-care test that can be performed at point of service, are now urgently needed.

This report by Médecins Sans Frontières (MSF) seeks to identify the next steps to improving access to viral load testing in resource-limited settings, by:

  • Describing the importance of viral load monitoring
  • Assessing the current state of play in terms of implementation of viral load testing in the developing world
  • Exploring how to overcome technical barriers by looking at the research and development (R&D) pipeline and defining the ideal specifications of a viral load test for resource- limited settings
  • Identifying strategies to overcome market barriers in order to make viral load monitoring more affordable.

With complexity and cost acting as the largest barriers to scale up, there is an urgent need to push forward the development and field validation of simple and affordable laboratory-based and point-of-care viral load tests.

To achieve this end, the following is proposed:

  • In the short- to medium-term: the HIV community must work to ensure that viral load testing becomes the basic standard of care. Donors should create incentives for more manufacturers to enter the market to increase competition and reduce prices. Strategies to reduce costs and to generate market competition should be explored. This includes: price transparency, pooling demand, analysing and removing patent barriers where they exist, and giving preference to ‘open systems’ to allow for greater competition on reagents and instruments. Operational research should be performed to accelerate the possibility of using a phased approach to replace immunological monitoring with virological monitoring, and diagnostic regulatory systems specific for resource-limited settings should be put in place.
  • In the medium- to long-term: Donors should fund the field validation and implementation of new tools for specific use in resource-limited settings and support their roll-out. Finally, future viral load test development should consider screening for key drug resistance mutations to support treatment switching decisions.

Funding the implementation of viral load should not be seen as a luxurious and avoidable expense, but should rather be recognised as a necessary and potentially cost-saving addition to current international commitments to scaling up treatment.