Researchers in the HIV cure race, closer to remission, but not yet to a universal cure

Researchers in the HIV cure race, closer to remission, but not yet to a universal cure | Photo: Julia Koblitz

Published on 18 March 2026 at 01:41 GMT

By Editorial Team SDG3

Spanish HIV cure research is moving from extraordinary cases towards practical remission strategies. 

Spain’s researchers are not claiming that a universal HIV cure has arrived. What they are doing, with unusual consistency, is helping to narrow the distance between laboratory promise and clinical reality. That matters well beyond Spain. In 2024, an estimated 40.8 million people were living with HIV worldwide, 1.3 million people acquired the virus and about 630,000 died from AIDS related illnesses, despite major gains in treatment access. Against that backdrop, work led from Barcelona and Madrid is increasingly important because it focuses on the central problem that has frustrated the field for decades, the viral reservoir, the pockets of virus that persist even when standard treatment suppresses HIV to undetectable levels.

The most visible Spanish contribution has come through IrsiCaixa, the Catalan institute that has become one of Europe’s best known centres for HIV cure research. In 2024, the international IciStem consortium, co coordinated by IrsiCaixa, reported the so called Geneva patient, described as the first person to achieve sustained HIV remission after a stem cell transplant without the donor carrying the usual CCR5 protective mutation. More than 32 months after stopping antiretroviral therapy, no virus had been detected in the blood. That is scientifically significant because earlier “cure” cases had appeared to depend heavily on a rare genetic mutation in donor cells. The Geneva case suggests that remission may, at least in some circumstances, be possible through other biological pathways as well.

This is not a cure that can be rolled out in ordinary clinics. Stem cell transplantation remains a high risk intervention reserved for people who also need treatment for life threatening blood cancers. Researchers and clinicians are explicit that it is not a scalable answer for the millions of people living with HIV. But such cases still matter. They provide a map of what biological mechanisms might make durable remission possible, and they help researchers test which parts of these exceptional outcomes could eventually be reproduced through safer tools such as antibodies, therapeutic vaccines, immune modulation or gene based approaches.

Spain’s importance to the field lies not only in these headline grabbing cases, but also in the quieter work of reducing the viral reservoir before any cure strategy is attempted. A recent IrsiCaixa study covering nearly 900 people treated over three decades found that those who started treatment after 2007 had a viral reservoir up to four times smaller than those treated earlier. The shift coincided with improved antiretroviral regimens and with guidelines favouring immediate treatment after diagnosis. In other words, the better HIV care becomes, and the faster treatment begins, the more realistic future remission strategies may be. Cure science, in this sense, starts with ordinary public health.

The viral reservoir remains the biggest barrier to an HIV cure. That phrase can sound technical, but its public health meaning is straightforward. Antiretroviral therapy can stop HIV from damaging the immune system and prevent sexual transmission when viral load is undetectable, yet it does not eliminate the virus from hidden cellular sanctuaries. This is why people generally need lifelong treatment. Spanish teams are among those trying to weaken that reservoir from several angles, by treating very early, by training the immune system to recognise conserved parts of the virus, and by studying why a small number of people control HIV unusually well without standard progression. The work of researchers such as Maria Salgado at IrsiCaixa, focused on functional cure models, reflects that broader scientific turn from eradication rhetoric towards controlled remission.

That same logic can be seen in the therapeutic vaccine programme linked to IrsiCaixa and Fundació Lluita contra les Infeccions. In March 2025, the phase II AELIX 003 trial reported that a combination of the HTI therapeutic vaccine and the immune modulating drug vesatolimod was safe and generated an immune response that improved HIV control during a supervised interruption of antiretroviral therapy in some participants. All participants eventually experienced viral rebound, which underlines the limits of the approach. Still, the result matters because it suggests the immune system can be trained to hold the virus down better, at least for a period, without continuous medication. That is not a sterilising cure, but it is a meaningful step towards treatment free remission.

The goal is increasingly remission, not eradication at any cost. That distinction is more than semantics. For researchers, remission means controlling HIV without daily drugs for sustained periods, even if traces of the virus remain somewhere in the body. For people living with HIV, it could eventually mean fewer side effects, less medical dependency and a different relationship to long term care. Yet the scientific optimism needs discipline. Even Spain’s most promising programmes have not shown that people can reliably stop treatment indefinitely. The field is closer to understanding the route than to reaching the destination.

Spain also offers a useful example of how community care and cure research intersect. The Early cART programme, run with Fundació Lluita contra les Infeccions, IrsiCaixa and BCN Checkpoint, has shown how rapidly linking people to treatment after infection can improve individual outcomes and reduce the viral reservoir. Between 2014 and 2022, the average time from infection to treatment initiation in the programme fell from 73 days to 27, while the time between a positive test and a specialist visit fell from 11 days to 3. That matters because early treated cohorts are especially valuable for cure studies: the less time HIV has had to establish its reservoir, the better the odds for future remission strategies.

Early diagnosis may be as important as any laboratory breakthrough. This is where the public interest story becomes harder and more political. In the WHO European Region, more than half of HIV diagnoses are still made late, and WHO Europe has warned that under diagnosis and late diagnosis are holding back progress towards ending AIDS as a public health threat. Late diagnosis is not simply a clinical problem. It reflects stigma, weak testing pathways, patchy information and unequal access to care, especially for migrants and marginalised groups. A country can produce world class cure research and still lose ground if too many people are diagnosed after avoidable delay.

That is why civil society remains central to the story. Projecte dels NOMS-Hispanosida, which founded BCN Checkpoint, emerged from the HIV affected community itself and still combines testing, counselling, prevention and advocacy. The organisation says it helped pioneer Spain’s HIV Testing Day and has served as a consultative body for WHO, UNAIDS and ECDC on guidance for HIV and STI prevention and diagnosis among men who have sex with men. gTt-VIH, another Spanish non profit, provides daily community based information on HIV treatment, prevention and related rights, including multilingual materials for migrants navigating Spain’s health system. CESIDA, Spain’s state HIV co ordinating platform, has long worked on discrimination and legal protection, a reminder that scientific progress alone does not dissolve social exclusion.

An HIV cure will fail people if access and rights are left behind. In journalistic terms, this is where the story connects most clearly to the United Nations sustainable development agenda. It speaks directly to SDG 3, good health and well being, because cure and remission research could reshape long term treatment. It also touches SDG 10, reduced inequalities, because the benefits of scientific progress depend on who gets tested early, who can enter care quickly and who is protected from discrimination. There is an indirect link to SDG 16, peace, justice and strong institutions, where legal safeguards and community trust determine whether public health systems can reach the people most at risk. These are not decorative labels. They describe the conditions under which biomedical advances become socially meaningful.

Spain is helping redefine what “closer to a cure” actually means. Not a miracle announcement, not an imminent end to lifelong treatment for everyone, but a steady convergence of better drugs, faster diagnosis, smaller reservoirs, more precise immune therapies and stronger community partnerships. The country’s researchers are near the forefront because they are working across all those fronts at once. The harder truth is that HIV science is still moving through increments, not leaps. The encouraging truth is that these increments are becoming more coherent. For a field long marked by disappointment, that may be the most credible sign of progress yet.

Further information:

·       IrsiCaixa, a leading Spanish HIV research institute involved in reservoir studies, functional cure research and the IciStem consortium. https://www.irsicaixa.es/en

·       Fundació Lluita contra les Infeccions, a non profit clinical research and care organisation working on HIV treatment, therapeutic vaccines and early diagnosis pathways. https://lluita.org/en/

·       Projecte dels NOMS-Hispanosida / BCN Checkpoint, a community based NGO focused on HIV testing, prevention, counselling and support, especially for gay and trans communities. https://www.bcncheckpoint.com/projecte-dels-noms/?lang=en

·       gTt-VIH, a civil society organisation that provides community based HIV treatment information, rights advocacy and multilingual resources. https://www.gtt-vih.org/

·       CESIDA, Spain’s national HIV civil society platform, relevant for anti discrimination, legal advocacy and public health access. https://www.cesida.org/