AIDS vaccine seems to have 'cured' five patients
The treatment, developed by researchers in Spain, allowed patients to stop taking regular antiretroviral drugs (ART) - the current method of suppressing HIV.
Scientists have not yet tested the results in a large-scale clinical trial, but say the vaccine be a "functional cure".
It is the first step to success in a field that has failed to find a vaccine in the last 30 years.
A new vaccine has 'functionally cured' five people with HIV and could eliminate the need for antiretroviral drugs (ART), says new research:
"It's proof of the concept that through therapeutic vaccination we can actually re-educate our T cells to control the virus," says Beatriz Mothe of the IrsiCaixa AIDS Research Institute in Barcelona, Spain.
"This is the first time we see that this is possible in humans."
The search for an AIDS vaccine has generated massive investment and intensive efforts, but so far no vaccine has hit the market.
After efforts and investments tried and failed to bring a mainstream vaccine that would prevent HIV infection, the researchers decided to test therapeutic vaccines.
They aim to help infected people keep the virus under control for months or even years without ART drugs.
Always The Reservoirs
Mothe and his colleagues used an HIV vaccine made by Professor Tomáš Hanke of Oxford University in the United Kingdom.
The researchers theorized that while drugs reduced HIV levels, they limited the virus's ability to integrate into their chromosomes, leaving them with relatively small reservoirs of infected cells.
That should make it easier to contain the virus if drugs are stopped, especially with the help of a vaccine, they said.
Scientists injected participants with a series of three doses of the vaccine and they stopped taking ART.
After four weeks, eight of the patients saw the virus recover. But the other five patients went from six to 28 weeks without having to restart treatment.
The virus has become temporarily undetectable, but has never exceeded 2.000 copies per milliliter, which is the criterion for restarting treatment.
It is proof of the concept that through therapeutic vaccination we can actually re-educate our T cells to control the virus.
from Over fifty studies
Of the more than 50 therapeutic vaccine trials to date, this is the first to "significantly" boost the immune system, according to Dr. Steven Deeks, an HIV / AIDS researcher and clinician at the University of California, San Francisco. .
He is 'cautiously optimistic'that the data will inspire others to study the approach.
Immunologist Daniel Douek of the National Institute of Allergy and Infectious Diseases in Bethesda, Maryland, is much more skeptical.
"The results are encouraging, but it is difficult to assess what the procedure was because of the uncontrolled nature of the study and the fact that people who stay out of [ART] are nonetheless viremic," said Douek. .
Mothe said previous "treatment discontinuation studies" - on people who started ART soon after being infected - found that only 10% of their infections were under control for more than four weeks.
In the Barcelona study, the rate was 38%.
HIV notoriously avoids immune attacks - and preventive vaccination - through mutations.
Visible Need for Greater, Better-Controlled Studies
The researchers believe the partial success of the study may be because the vaccine contains HIV genes that encode “highly conserved” internal structures and enzymes that cannot change much without harming the virus.
Deeks said: "If current trends persist, it's hard to argue that the vaccine strategy has not done anything, but controlled studies are needed."