Tag Archives: HIV
Early HIV drugs ‘may not stop virus’
Latest HIV vaccine doesn’t work; govt halts study
WASHINGTON: The latest bad news in the hunt for an AIDS vaccine: the government halted a large US study on Thursday, saying the experimental shots are not preventing HIV infection.
Nor did the shots reduce the amount of the AIDS virus in the blood when people who had been vaccinated later became infected, the National Institutes of Health said.
“It’s disappointing,” said Dr. Anthony Fauci, head of NIH’s National Institute of Allergy and Infectious Diseases but added that “there was important information gained from this” study that will help determine what to try next.
The study had enrolled 2,504 volunteers, mostly gay men, in 19 cities since 2009. Half received dummy shots, and half received a two-part experimental vaccine developed by the NIH. All were provided free condoms and given extensive counselling about the risks for HIV.
It is a strategy known as “prime-boost.” A DNA-based vaccine made with genetically engineered HIV material is given to prime the immune system to attack the AIDS virus.
Then a different vaccine, encasing the same material inside a shell made of a disabled cold virus, acts as a booster shot to strengthen that response. Neither vaccine could cause HIV.
The idea: train immune cells known as T cells to spot and attack the very earliest HIV-infected cells in someone’s body. The hope was that the vaccine could either prevent HIV infection, or help those infected anyway to fight it.
A safety review this week found that slightly more study participants who had received the vaccine later became infected with HIV. It is not clear why. But the difference was not statistically significant, meaning it may be due to chance.
Overall, there were 41 HIV infections in the vaccinated group and 30 among placebo recipients.
When researchers examined only participants diagnosed after being in the study for at least 28 weeks – long enough for the shots to have done their job – there were 27 HIV infections among the vaccinated and 21 among the placebo recipients.
The NIH said Thursday that it is stopping vaccinations in the study, known as HVTN 505, but that researchers will continue to study the volunteers’ health.
Josh Robbins, 30, is among the participants who became infected. He said he is glad he was in the study, because its close monitoring meant he was diagnosed and treated much sooner than most people – and he is feeling great – and because the findings help science.
“We’ve got to keep moving forward,” Robbins said. The study “certainly can lead us down a new direction to hopefully find something that might work.”
Multiple attempts at creating an AIDS vaccine have failed over the years. A 2009 study in Thailand is the only one ever to show a modest success, using a somewhat different prime-boost approach.
Newer research suggests another approach – to try creating powerful antibodies that could work a step earlier than the T-cell attack, before HIV gets inside the first cell.
Both approaches need continued research funding, said Mitchell Warren of the international AIDS Vaccine Advocacy Coalition.
“Clearly an AIDS vaccine remains critical,” he said.
Malawi gets 1,000 new HIV infections a week: official
AIDS-ravaged Malawi, where over a tenth of the population is HIV positive, records on average 1,000 new cases weekly, a top government official said Saturday.
“It?s a great concern to us that despite efforts by government to prevent HIV and AIDS, the country continues to register about 1,000 new cases of HIV every week,” Edith Mkawa, a senior health ministry secretary in charge of nutrition, HIV and AIDS, told reporters.
“The number is very high. It is frustrating the fight against HIV pandemic,” she said.
Mkawa said Malawi, where 11.8 percent of the 14 million citizens are HIV positive, “needs urgent action to attain zero new HIV infections.”
People “are not changing their behaviours. These behaviours are fuelling the spread of HIV at an alarming rate.”
The southern African nation has 350,000 people receiving free anti-retroviral drugs, up from 5,000 in 2004.
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