26th International AIDS Conference 2026 in Rio de Janeiro
Article by Walter Ceron

PrEP: A scientific success with political challenges

The first presentation traced the remarkable development of pre-exposure prophylaxis (PrEP) over the past fifteen years. The data presented show that preventive treatments can now very effectively reduce the risk of HIV infection. This is aided by a steadily growing range of prevention options: daily tablets, on-demand PrEP, vaginal rings, long-acting injections and new formulations currently under development.

According to the speaker, the effectiveness of PrEP is no longer up for debate – it is clearly proven by science. The real challenge lies rather in sustaining prevention programmes in the long term, ensuring they are adequately funded and making them accessible to all. Recent cuts to international funding, particularly for programmes supported by PEPFAR and USAID, could lead to a rise in new HIV infections despite the availability of highly effective prevention tools.

An HIV vaccine remains essential

The second presentation focused on advances in vaccine research. Despite the great successes of PrEP, the researchers emphasised that an effective vaccine remains essential to bringing the HIV epidemic under control in the long term.

The speakers outlined the key scientific challenges: the virus’s high mutation rate, its enormous genetic diversity and its ability to evade the immune system make the development of a vaccine considerably more difficult.

Nevertheless, several promising approaches are currently being pursued:

• the development of new antigens using artificial intelligence;
• mRNA-based vaccines;
• nanoparticle technologies;
• broadly neutralising antibodies (bNAbs);
• strategies for simultaneously stimulating antibody and T-cell responses.

The researchers anticipate that future generations of vaccines will likely combine several of these technologies to achieve more sustainable and effective protection.

Prevention cannot succeed without equality

The third presentation focused on trans communities and the importance of truly inclusive prevention.

The data presented show that trans people continue to be disproportionately affected by HIV. The reasons for this include a variety of structural barriers, such as discrimination, precarious living conditions, restricted access to healthcare, inadequate collection of epidemiological data, and the failure to take their needs into account in many areas of health policy.

The speaker advocated an integrated prevention approach in which gender-affirming healthcare, psychosocial support, sexual health, social services and HIV prevention are provided together.

The results presented show that, through such integration, trans people gain easier access to HIV testing, PrEP and antiretroviral therapies, and achieve better overall health outcomes. The speaker also emphasised that access to gender-affirming healthcare is in itself an important contribution to HIV prevention.

Conclusion

The plenary session highlighted that the scientific foundations for a significant reduction in new HIV infections are already in place. Whether this potential can be realised will depend, in the coming years, primarily on whether governments, health systems and communities continue to invest in prevention, drive forward innovative vaccine approaches and ensure equitable access to new prevention and treatment options for all affected population groups.