The UNAIDS 2016–2021 Strategy, which the UNAIDS Programme Coordinating Board adopted in 2015, was a bold call to accelerate the HIV response and reach the people being left behind. It called for frontloading investments in that response so a range of ambitious targets for 2020 could be reached. It was also one of the first United Nations strategies to be aligned with the Sustainable Development Goals and was aimed at guiding and supporting locally tailored responses while fostering new forms of leadership and accountability at the regional, country and community levels. 

Since 2015, the global context has changed dramatically. Even before the COVID-19 pandemic, progress in the global AIDS response was not on-track to reach the 2020 HIV targets. The most recent data (for 2019) show that dramatic rapid progress is necessary––and possible. UNAIDS’ 2020 global AIDS update, Seizing the moment, highlights the gains made along the HIV testing and treatment cascade: an estimated 81% of people living with HIV knew their HIV status in 2019 and more than two thirds (67%) of all people living with HIV were on antiretroviral therapy. The number of people living with HIV on treatment has tripled since 2010 (1). However, only a small number of countries will reach the 90–90–90 targets by the end of 2020. As a result, in more than a quarter (28%) of countries, less than half of all people living with HIV had suppressed viral loads in 2019. 

The barriers and disparities in the global AIDS response are increasingly evident between regions, countries, and populations and communities. Unequal access to health and social services often mirrors, exacerbates and overlaps with other inequalities, including gender inequalities and inequalities resulting from discrimination based on income, race, age, ethnicity, disability, immigration status or sexual orientation. These inequalities shape a global epidemic in which a majority of new HIV infections are among key populations and their partners. The inequalities underpin the HIV epidemics in sub-Saharan Africa, the epicentre of the global pandemic and where girls account for 5 in 6 new HIV infections among adolescents aged 15–19 years. At the same time, we cannot forget that we have the science, tools and commitment to prevent each new HIV infection and to avoid each AIDS-related death. We must have the courage to ask ourselves why we are failing and what we must do to get back on-track. 

This evidence review is one component of the Strategy review process. It asks critical questions as we prepare to develop the next UNAIDS Strategy. What is working and how does it need to be sustained or scaled-up? Where and in what respects are we falling behind, and why? How do we overcome the gaps and obstacles that stand in the way of consistent progress across all communities, countries and regions? How do we highlight the importance of fighting stigma and discrimination, changing harmful laws, supporting access to legal redress and confronting gender inequality in order to achieve the next Strategy's targets among all populations and in every community in a country? 

The review highlights approaches that we can build on, especially in areas where the evidence-informed approaches of the current UNAIDS Strategy remain sound but have not been implemented with sufficient speed, quality or scale. The review also provides a sobering analysis of where the global HIV response is falling short. It sets the scene for a deeper discussion about the steps that are needed to support countries and communities as they strive to leave no one behind and end AIDS as a public health threat. Together with several other inputs, the review will inform the development of the next UNAIDS Strategy and it will guide the future direction of the global HIV response.