Positive news in a long battle

[Steven_Draker]

NY Times: "For First Time, AIDS Vaccine Shows Some Success"

 

A new AIDS vaccine tested on more than 16,000 volunteers in Thailand has protected a significant minority against infection, the first time any vaccine against the disease has even partly succeeded in a clinical trial.

 

Scientists said they were delighted but puzzled by the result. The vaccine — a combination of two genetically engineered vaccines, neither of which had worked before in humans — protected too few people to be declared an unqualified success. And the researchers do not know why it worked.

 

“I don’t want to use a word like ‘breakthrough,’ but I don’t think there’s any doubt that this is a very important result,” said Dr. Anthony S. Fauci, director of the National Institute of Allergy and Infectious Diseases, which is one of the trial’s backers.

 

“For more than 20 years now, vaccine trials have essentially been failures,” he went on. “Now it’s like we were groping down an unlit path, and a door has been opened. We can start asking some very important questions.”

 

Results of the trial of the vaccine, known as RV 144, were released at 2 a.m. Eastern time Thursday in Thailand by the partners that ran the trial, by far the largest of an AIDS vaccine: the United States Army, the Thai Ministry of Public Health, Dr. Fauci’s institute, and the patent-holders in the two parts of the vaccine, Sanofi-Pasteur and Global Solutions for Infectious Diseases.

 

Col. Jerome H. Kim, a physician who is manager of the army’s H.I.V. vaccine program, said half the 16,402 volunteers were given six doses of two vaccines in 2006 and half were given placebos. They then got regular tests for the AIDS virus for three years. Of those who got placebos, 74 became infected, while only 51 of those who got the vaccines did.

 

Although the difference was small, Dr. Kim said it was statistically significant and meant the vaccine was 31.2 percent effective.

 

Dr. Fauci said that scientists would seldom consider licensing a vaccine less than 70 or 80 percent effective, but he added, “If you have a product that’s even a little bit protective, you want to look at the blood samples and figure out what particular response was effective and direct research from there.”

 

The most confusing aspect of the trial, Dr. Kim said, was that everyone who did become infected developed roughly the same amount of virus in their blood whether they got the vaccine or a placebo.

 

Normally, any vaccine that gives only partial protection — a mismatched flu shot, for example — at least lowers the viral load.

 

That suggests that RV 144 does not produce neutralizing antibodies, as most vaccines do, Dr. Fauci said. Antibodies are long Y-shaped proteins formed by the body that clump onto invading viruses, blocking the surface spikes with which they attach to cells and flagging them for destruction.

 

Instead, he theorized, it might produce “binding antibodies,” which latch onto and empower effector cells, a type of white blood cell attacking the virus.

 

Whatever the vaccine does, he said, it does not seem to mimic the defenses of the rare individuals known to AIDS doctors as “long-term nonprogressors,” who do not get sick even though they are infected. They have low viral loads because they block reproduction in some way that is still mysterious.

 

“If we knew what immune response did it, we’d be able to be a lot more efficient in targeting it,” Dr. Kim said.

 

Also, the RV 144 tested in Thailand was designed to combat the most common strain of the virus circulating in Southeast Asia. Different strains circulate in Africa, the United States and elsewhere, and it is not clear that the vaccine would have similar results, even in modified form.

 

The thousands of Thais chosen were a cross-section of the Thai young adult population, not just high-risk groups like drug injectors or sex workers, Dr. Kim said.

 

One of the substances that were combined to make RV 144 is Alvac-HIV, from Sanofi-Pasteur, a canarypox virus with three AIDS virus genes grafted onto it. Variations of Alvac were tested in France, Thailand, Uganda and the United States; it was found safe but generated little immune response.

 

The other, Aidsvax, was originally made by Genentech and is an engineered version of a protein found on the surface of the AIDS virus; it is grown in a broth of hamster ovary cells.

 

It was tested in Thai drug users in 2003 and also in gay men in North America and Europe; it did not protect them against infection, and Genentech spun off the rights to develop the vaccine.

 

In 2007, two trials of a Merck vaccine in about 4,000 people were stopped early; it not only failed to work but for some men seemed to increase the risk of infection.

 

Combining Alvac and Aidsvax was a hunch by scientists: If one was designed to create antibodies and the other to alert white blood cells, might they work together even if neither worked alone?

 

Mitchell Warren, executive director of AVAC, the AIDS Vaccine Advocacy Coalition, which pushes for vaccines and other forms of prevention, was enthusiastic about the trial data.

 

“Wow,” he said. “This is a hugely exciting and, frankly, unexpected result. It changes our thinking in ways we hadn’t anticipated.”

 

“We often talk about whether a vaccine is even possible,” he added. “This is not the vaccine that ends the epidemic and says, ‘O.K., let’s move on to something else.’ But it’s a fabulous new step that takes us in a new direction.”

 

Mr. Warren said the finding showed the need for large human trials, expensive as they are. Studies in mice and monkeys have not been good at predicting what would work in people, and small human trials in which researchers test results by looking for antibodies in blood have limited value.

 

Dr. Fauci agreed.

 

“This is not the endgame,” he said. “This is the beginning.”

 

On the net:

http://www.hivresearch.org/phase3/factsheet.html

Vaccine coalition: http://www.avac.org/

UNAIDS: http://tinyurl.com/krq7kr

Government AIDS info: http://www3.niaid.nih.gov/topics/HIVAIDS/

[Guest Merlin]

I am not convinced. The difference in the number of people who did not become infected (between vaccinated and those who go placebos) is small enough to be a coincidence. This is confirmed by the fact that the vaccinated people who did get the disease experience no protection.

[+ purplekow]

The difference between the two groups is small but statistically significant. This is the measure used to determine whether this may have been a random event or not. While this is certainly a small step in the right direction, those with their glasses half empty will not see that.

[Guest Merlin]

I just don't believe the small difference in one test is sufficient to exclude random chance or coincidence.

[+ purplekow]

I just don't believe the small difference in one test is sufficient to exclude random chance or coincidence.

 

 

Statistical significance does not exclude random chance, however the likelihood that this is random event is measured by statistical significance. While not mentioned here, to be published, it is lower than 0.01%. I suppose you don't see the glass as half empty, you see your point of view as 0.01% full.

[JT Brooklyn]

Statistical significance does not exclude random chance, however the likelihood that this is random event is measured by statistical significance. While not mentioned here, to be published, it is lower than 0.01%. I suppose you don't see the glass as half empty, you see your point of view as 0.01% full.

 

The Best Protection..Use common sense...Play Safe Forever!

[Mark Gordon]

Statistical Significance

 

Unfortunately, many large clinical trials find some level of statistical significance with miniscule differences between groups without their findings having any clinical relevance. Given a sufficiently large sample, extremely small differences can be found to be statistically significant and statistical significance says nothing about the practical significance of a difference. We are talking about a difference of 23 infections between two groups of 8,201 participants, with 51 participants who took the vaccine still becoming infected. There have been a number of large AIDS vaccine trials over the last 20 years and one of them was bound to throw up an anomalous result. Keep in mind that, with proper marketing, there is the potential for billions to be made from results of dubious clinical importance.

[Lookin]

I don't think anyone is planning to roll out the vaccines based on this study. What I read is that there's a glimmer of light where there has not been one before.

 

These results are significant enough to re-energize the search for an effective vaccine, to provide some new insights, and to suggest directions for further research.

 

In my opinion, it's not a bad thing, it's not a neutral thing, it's a good thing.

 

Thanks to Steven for posting this!

[JT Brooklyn]

This Story also was on every News Channel Thurs Evening!

 

HIV/AIDS does of course effect the many "Straight Lives" it has touched also!

 

Hopefully in OUR Lifetimes there will be more than just "Study Results" every couple of Years!

[Lookin]

This Story also was on every News Channel Thurs Evening!

I know, but it almost seems that the news doesn't really settle in these days until it's been chewed on by the Illustrious Gentlemen of the Lounge. http://media.bigoo.ws/content/smile/character/character_178.gif http://www.anchoredbygrace.com/smileys/tophat.gif http://www.anchoredbygrace.com/smileys/tophat.gif http://media.bigoo.ws/content/smile/character/character_178.gif

 

 

HIV/AIDS does of course effect the many "Straight Lives" it has touched also!

 

It's interesting that this research was sponsored in Thailand by the U. S. Army.

 

 

Hopefully in OUR Lifetimes there will be more than just "Study Results" every couple of Years!

From your lips to God's ears!

[+ purplekow]

. We are talking about a difference of 23 infections between two groups of 13,201 participants, with 51 participants who took the vaccine still becoming infected.

 

It took 13000 participants to come up with 125 infections. Approximately 60% were in the non-vaccinated group. The number 23 is not based on 13000 but on the 125. In an election 60% is considered a landslide. In this case, this is more of a step in the right direction.

 

 

 

 

There have been a number of large AIDS vaccine trials over the last 20 years and one of them was bound to throw up an anomalous result. Keep in mind that, with proper marketing, there is the potential for billions to be made from results of dubious clinical importance.

 

There have not been a large number of human HIV vaccine trials. There have been three that are frequently quoted. This is the first to show a statistical difference. You are willing to say sooner or later there was bound to be an anomolous result. Less than 5 major studies and you assume one wrong. That is not statistically significant.

[uwsman2]

a really useful discovery?

 

I suspect that these test results will not ultimately turn out to be really useful unless they can determine WHY the vaccine is associated with a statistically significant decline in new infections in the test group compared to the control group. Without knowing why, it is difficult to capitalize on this demonstrated association....

[Guest]

Unfortunately, many large clinical trials find some level of statistical significance with miniscule differences between groups without their findings having any clinical relevance. Given a sufficiently large sample, extremely small differences can be found to be statistically significant and statistical significance says nothing about the practical significance of a difference. We are talking about a difference of 23 infections between two groups of 13,201 participants, with 51 participants who took the vaccine still becoming infected. There have been a number of large AIDS vaccine trials over the last 20 years and one of them was bound to throw up an anomalous result. Keep in mind that, with proper marketing, there is the potential for billions to be made from results of dubious clinical importance.

 

You are actually very right about this. It's amazing how even some doctors get confused between something that is statistically significant and something that is clinically significant. If one has a large enough sample, one can eek out even very small differences. Statistical significance just refers to how likely the difference is to be real versus by chance. This study seems very fishy to me also in that they chose a low-risk group to study. Why not study prostitutes, IV drug abusers, or gay men, for instance? I don't see this study as much to get excited about.

[+ Lucky]

HIV Study A Fluke?

 

More info to throw water on the conclusions we were led to believe could be drawn from this study:

 

http://online.wsj.com/article/SB125511780864976689.html?mod=WSJ_hpp_sections_news

[Guest greatness]

so sad

 

I don't like some journalists who write an article without fully understanding the material... They barely know anything about a medical research and try to write a report about it. They can try to learn but then it would take them too much time to write a report so they go to these sources who would provide them with what they want to publish. I don't blame these journalists.. They need their weekends and gossiping time in their offices, their long lunch breaks and socializing time with big company executives at Per Se at nights... So when they can find time to do some actual research ???... I haven't read a single public data/publication on this research yet so I can't say anything about it. I think journalists should have waited until it has been verified and replicated by a third independent party or at least it is presented and discussed at a major meeting. I believe in that short period of time between these two contradicting articles a pharmaceutical company secured their investors. Will investors ask their money back? I'm pretty sure that this is not going to be released because journalists involved will not probably report it. How media is played these days is so funny and controlling a few journalists to write favorable articles about a certain big company isn't hard.

 

 

 

More info to throw water on the conclusions we were led to believe could be drawn from this study:

 

http://online.wsj.com/article/SB125511780864976689.html?mod=WSJ_hpp_sections_news