Scientists say valproic acid can eradicate dormant HIV

Aug 14 2005

Early research by scientists in the U.S. suggests that valproic acid could be a potential way to eradicate dormant HIV infections.

A team at the University of North Carolina has shown that valproic acid, which is used to treat bipolar disorder, can also prevent HIV persisting in its latent phase.

The team say that the findings could boost HIV treatment and be a step towards preventing HIV from being a chronic disease.

But some experts are cautious and say much more research into the drug's effects was needed, and warn about being over-optimistic about the eventual introduction of this approach in HIV treatment.

Dr Chris Gadd, of the UK's Aidsmap, which offers advice on HIV/AIDS to patients and health professionals, says it is encouraging that this study is using an existing, licensed drug, and although the approach is still highly experimental, the study shows that it is feasible that the intensification of antiretroviral therapy with a new drug, coupled with the addition of valproate, can reduce the numbers of resting, infected cells.

HAART (highly-active antiretroviral therapy), which targets virus replication and restores immune function, has improved the outcome for patients with HIV.

But apparently the virus can remain dormant in some infected cells, meaning people with the virus have to continue taking medication, otherwise the virus will emerge from cells as soon as the drugs disappear.

Scientists already known that an enzyme called histone deacetylase 1 (HDAC1) helps HIV to persist in a latent phase of infection.

It is also known that Valproic acid stops this enzyme acting effectively.

To test this theory the researchers studied four people with HIV who were already on HAART.

The four were given enfuvirtide (Fuzeon), which stops the virus entering healthy cells for up to six weeks, to give them added protection against HIV.

Then a three-month course of valproic acid, taken twice daily, was then added to their treatment.

According to the researchers they found a 75% reduction in latent HIV infection in three of the four patients, over the period they were taking valproate.

Dr David Margolis, who led the study, says that suggests that eradication of established HIV infection might be achieved in a staged approach, but patients should possibly first be treated with standard antiretroviral regimens at an early stage of infection.

Margolis says that for those in whom viral replication is suppressed, latent viral infection could then be tackled with HDAC inhibitors, intensified therapy, or both.

Dr Jean-Pierre Routy of McGill University Health Centre in Montreal, Canada, agrees that the results, although preliminary, merit further urgent study, and could be a new therapeutic approach towards making HIV infection no longer a chronic disease.

The study and some of the comments on it, can be found in the Lancet.