The last IDIBELL Seminar, on 28th October, the Small Hall at the Hospital Universitari de Bellvitge, hosted the seminar “Update about HIV eradication” by Bonaventura Clotet PhD, Institute for AIDS Research (IrsiCaixa) Director, and talked about the different strategies to cure HIV.

The problem of VIH spreading and treatment is that, more and more, there are a growing number of new cases and the treatment is for life, having a huge human and economical cost. This last is about 4.000 euros/year par person. “We need to reduce the cost of the treatment”, said Dr. Clotet.

“We have seen that the highly active antiretroviral therapy (HAART) is effective”, continued the IrsiCaixa director. It has been proved that the suppression to below detectable HIV-1 is efficient. However, the low level in plasma of viral load (virulemia) persists. And the immune activation diminishes, but it does not normalise. Ten years ago in a study were indicated that the eradication of the virus was unlikely.

“What accounts for the extreme persistence of the virus reservoir?”, asked the Dr. Clotet. HAART stops all viral replication. The residual replication continues due to incompletely suppressive HAART.

The prediction is that HAART will stop the active replication. Latency allows lifelong persistence of the virus.

Strategies to cure HIV

The IrsiCaixa researchers had initiated a study years ago. They wanted to find if with intensification with Raltergravir of the HAART treatment there was an improvement of the treatment. They saw a decrease of the parameters activation related with the VIH dissemination. “We concluded that the intensification of HAART with Raltergravir, had a decrease of the reservoirs”, said Dr. Clotet.

After the study, they have received a lot of critics. Then they had decided to make another study about the intensification of this treatment. They looked for patients recently infected, in order to investigate their hypothesis and they have achieved the same results than the previous study. Early treatment was a key point to diminish the reservoirs.

Can a therapeutic vaccine synergize with an anti-latency agent?

There are some possible models for functional cure. “Is there an immune control of the HIV Reservoirs? Can HIV-specific immunity control the HIV Reservoirs? We work in a trial for a HIV vaccine in 2008. A therapeutically vaccine should induce an anti-HIV CD8 T cells or Abs, to kill the residual replicating cells or block cell to cell HIV spreading”, said the researcher.

Other promising strategy

Dr. Clotet talked about Timothy Brown, the first person to have been cured of HIV. Brown had Leukemia and he was treated by stem cell transplantation. The donor was CCR5 Gene Disrupted. Then, they proved the cure. This kind of treatment is well tolerated, and this kind of approach has been patented then it is not possible to use it for the rest of researchers.