Chronic treatment of HIV using antiretroviral combinations manages to prevent disease progression in most cases. However, this approach to treatment is costly, toxic for the body and does not eradicate the infection. Once a person stops taking their medication, the virus will reappear in a matter of weeks.
For these reasons, a major goal of current research is for people living with HIV to stop needing treatment.
This goal can be achieved in two ways: by eradicating the virus entirely, or by achieving what is called a "functional cure", which also works for other viral infections. A functional cure is when a virus is not completely eliminated by the body's immune system but can be controlled without medication.
IrsiCaixa is pursuing this line of research by studying various combination strategies: therapeutic vaccines (for people who are infected), antibodies, drugs that reactivate the latent virus, etc.
Viral reservoir studies
To achieve a functional cure, IrsiCaixa is studying HIV activity in reservoirs, which are cells where the virus remains latent and from where infection is reactivated when a person stops taking treatment. While the cell remains inactive, the viral reservoir is invisible to the immune system and the antiretroviral treatment fails to detect and remove it. The reservoir explains why current treatment has to be for life. For this reason, finding out how to identify, activate and destroy the reservoir would be a definitive step towards HIV eradication.
Prevention — the best strategy
All research aimed at eradication or functional cure is closely linked to the development of tools to prevent HIV infection, whether through preventive vaccines or drugs or through antibodies that protect against the virus.
Studying the immune response in people at high risk of contracting HIV helps with developing strategies to prevent infection. IrsiCaixa is working on a therapeutic vaccine for people living with HIV called HTI and on monoclonal antibodies that neutralize HIV in the body and increase the activity of natural killer cells that destroy infected cells. In the future, these tools could form part of a combined prevention-eradication strategy.