← Autodidact Archive · Original Dissent · Gaius Marius
Thread ID: 5207 | Posts: 4 | Started: 2003-02-25
2003-02-25 13:44 | User Profile
The latest AIDS vaccine was completely ineffective among whites but protected three quarters of blacks! Racial differences, anyone? It appears that blacks need only a small amount of help to beat AIDS but whites are not so lucky.
[url=http://www.news.com.au/common/story_page/0,4057,6038045%255E2,00.html]http://www.news.com.au/common/story_page/0...5%255E2,00.html[/url]
[SIZE=2]AIDS vaccine fails[/SIZE] By Pascal Barollier in Washington 25Feb03
HOPES for an AIDS vaccine have been dashed for another decade, after a mass trial failed to protect most volunteers against HIV infection.
But the makers of drug, California-based VaxGen Inc, said the three-year trial showed AIDSVAX did provide some protection to blacks and Asians.
"Overall, what we see is the trial failed," Vaxgen president Donald Francis told a Washington press conference.
He said the vaccine had appeared to work in only 3.8 per cent of the volunteers who took it.
Don Baxter, the executive director of the Australian Federation of Aids Organisations, said trial's failure meant a effective vaccine was at least a decade away.
"People were hopeful and I was hopeful that there might be a 20 or 30 per cent reduction in HIV incidents but the fact that there is absolutely none really is very disappointing," he told ABC radio.
The vaccine or a dummy version was administered in three doses to 5009 volunteers, primarily gay men in the United States, as well as Canada, Puerto Rico and the Netherlands.
Two-thirds were given the vaccine, and one-third the placebo.
The California biotech company said there was a "statistically significant" reduction of HIV infection amongst blacks and Asians.
"There were 67 per cent fewer HIV infections among ethnic minorities, other than Hispanic individuals," the company said. "There were 78 per cent fewer HIV infections among black volunteers who received vaccine compared to placebo recipients."
Phillip Berman, VaxGen's senior vice president of research and development and inventor of the vaccine, said those results were heartening but admitted that researchers did not know why this had happened.
They showed "certain groups have a better immune response" to HIV and this warranted further study, he argued.
However, that contention was questioned by the International AIDS Vaccine Initiative (IAVI), a New York-based organisation that is pushing to promote a vaccine against HIV.
It said the number of infections among ethnic volunteers was too small to draw any firm conclusion. There were only 13 infections among black volunteers, four in the vaccine group and nine in the placebo group.
In addition all the volunteers received counselling on safe sex, a factor known by scientists to affect infection rates.
Vaxgen shares plunged 54.38 per cent to $US5.94 ($9.12) after the announcement.
The value to any company that finds the vaccine is enormous. According to UN figures, around 20 million people have already died from acquired immune deficiency syndrome (AIDS) and another 42 million people had HIV or AIDS in 2002.
AIDS campaigners said, however, that the hunt for a vaccine must go on. About 30 potential vaccines are at various stages of development. Most are therapeutic and to be taken after infection.
"The news on VaxGen's AIDSVAX is disappointing, but we are not discouraged," IAVI president Seth Berkley said. "The search for an AIDS vaccine will - and must - go on.
"A vaccine is the world's best hope to end the spread of a virus that infects nearly 15,000 men, women and children daily and threatens the survival of whole communities."
Peter Piot, executive director of the UN agency UNAIDS, said some of the results were "promising".
"The trial provides clear evidence that a vaccine can work. However, there is an urgent need for more targeted research to find out why the candidate vaccine only seems to work in certain population sub-groups."
AIDSVAX is the only vaccine to have been tested through all three phases of medical trials - a long, arduous and expensive process for assessing safety and effectiveness that takes a candidate medicine out of the laboratory and into the public domain.
The trial vaccine is based on priming antibodies, the first line of the body's defence.
Its goal is to get the antibodies to identity the so-called gp120 protein on the surface of HIV which enables the virus to dock with an immune-system cell, the first stage before penetrating it.
Although lab tests had shown that gp120 antibodies could be stimulated, there had already been some evidence to cast doubt on whether the response has the punch to destroy the virus.
Disappointment with antibodies has prompted many AIDS vaccine researchers to try another tack, switching away from antibodies and towards cellular immunity: getting killer lymphocytes to recognise and destroy cells already infected by HIV.
This would not, however, destroy the virus in the bloodstream, which means it could still infect other people through, for instance, shared drug syringes.
A senior European researcher said the results from this first-generation vaccine were a "disappointment" but "not a surprise".
"We have known since the beginning that antibody-based vaccine strategies will not be enough to fight the incredible diversity of this virus," said Jean-Gerard Guillet, head of the preventive vaccine programme at ANRS, France's National AIDS Research Agency.
He put the typical cost of a Phase III trial at more than $US70 million ($115 million).
A Phase III trial of AIDSVAX is also underway among injection drug users in Thailand, testing a formulation that is designed to protect against the HIV subtypes B, prevalent in North America and Europe, and E, which is prevalent in central Africa and southeast and east Asia.
[url=http://www.news.com.au/common/story_page/0,4057,6038045%255E2,00.html]http://www.news.com.au/common/story_page/0...5%255E2,00.html[/url]
[SIZE=2]AIDS vaccine results disappoint[/SIZE] By Richard Ingham in Paris 25Feb03
SCIENTISTS have expressed disappointment after the first mass trial of an anti-HIV vaccine showed the long-awaited molecule had largely failed to shield volunteers from the AIDS virus.
Experts branded the human immunodeficiency virus (HIV) a devious foe and said the difficulties had only been confirmed by the setbacks encountered by AIDSVAX - the first vaccine to be assessed on thousands of volunteers.
A senior European researcher said AIDSVAX was "the first generation" of prototype vaccines and admitted many had already doubted privately that it would work.
"It is a disappointment but, for scientists, not a surprise," said Jean-Gerard Guillet, head of the preventive vaccine programme at ANRS, France's National AIDS Research Agency.
"We have known since the beginning that antibody-based vaccine strategies will not be enough to fight the incredible diversity of this virus."
AIDSVAX primes antibodies, the frontline soldiers in the body's immune system.
Its aim is to get the antibodies to spot the so-called gp120 protein on the surface of HIV which enables the virus to dock with an immune-system cell, the first stage before penetrating it.
Guillet said many AIDS vaccine researchers were now turning away from antibodies and instead focusing on cellular immunity: getting killer lymphocytes to seek and destroy HIV-infected cells.
Seth Berkley, president of the International AIDS Vaccine Initiative (IAVI), a New York-based organisation, said: "Scientists remain confident that an AIDS vaccine is possible.
"Alternative AIDS vaccines, employing different design strategies, are now in development, and some have already entered human trials. These must move forward through further study, without delay."
Preliminary results unveiled by AIDSVAX's makers, VaxGen Inc, showed the vaccine provided "approximate efficacy" of only 3.8 per cent among 5009 volunteers in North America, Puerto Rico and the Netherlands who were given three injections over three years.
It had been hoped it would be at least 30-per cent effective, a level that could have warranted distributing it around the world as an adjunct to safe-sex techniques.
VaxGen acknowledged the trial had failed to meet the primary goal, but said it still saw some good news - the vaccine may be more effective for several ethnic groups.
Among "non-white" volunteers, the efficacy rate was 67 per cent, and it was highest among blacks, at 78 per cent, it said.
"This is the first time we have specific numbers to suggest that a vaccine has prevented HIV infection in humans," said Phillip Berman, VaxGen's senior president of research and development and AIDSVAX's inventor.
"We're not sure yet why certain groups have a better immune response, but these preliminary results indicate that a surface protein that stimulates neutralising antibodies correlates with prevention of infection."
Among the wider scientific community the consensus was that the apparent protection for ethnic volunteers was intriguing and deserved further inquiry.
But no observer agreed with the conclusion, implied by VaxGen, that genetic differences might have helped blacks and Asians to respond better to the vaccine.
Peter Piot executive director of the UNAIDS, the UN agency fighting the global AIDS pandemic, said the figures on ethnic volunteers were "promising" and warranted "urgent... targeted research" to find out more.
Berkley said the number of infected blacks was only 13, four of whom were in the vaccine group while nine were in a group that received a dummy lookalike, and the number of infected Asians was just four, with two in each group.
Such small figures meant that it was impossible to rule out statistical anomalies or that blacks and Asians had responded better to the safe-sex counselling given to all of the volunteers, he said.
There was a theoretical possibility of genetic differences, but this had to be demonstrated clinically, Berkley said.
For instance, blood samples, taken from the blacks and Asians, would have to prove that these volunteers had had a better immune response to the vaccine, he said.
2003-02-25 14:08 | User Profile
There is already a cure for AIDS, and it's called Behavior Modification.
Isn't it bizarre that these studies are performed with a placebo group-- within this placebo group a certain percentage contract a deadly disease which condemns them to slow death. This means that some of these people in the study engage in unsafe sex practices knowingly. This is bizarre. They know perfectly well that they are subjects in a double-blind experiment where failure means slow death, and yet they still practice unsafe sex! I mean do they deserve to die for being Stupid or what?
2003-02-26 03:45 | User Profile
Originally posted by Bardamu@Feb 25 2003, 09:08 They know perfectly well that they are subjects in a double-blind experiment where failure means slow death, and yet they still practice unsafe sex! I mean do they deserve to die for being Stupid or what?
Well it is a might good thing this vacine might help protect blacks. Sometimes they just dont have the facts. This poor criminal in SA was never told that AIDs is rampant in prison otherwise he wouldn't have engaged in buggery.
[url=http://forum.originaldissent.com/index.php?act=ST&f=6&t=6341&st=0&#entry31815]OD Link[/url]
2003-02-26 08:07 | User Profile
**It will be interesting to see the medical establishment hush all this up, seeing as how race is only skin deep. **
[color=blue]Playing hush up concerning race will continue in all facets of our society save medicinal purposes, as it has been ordained that no harm must come to our precious minorities. Consider the following piece -- on second page of an Izzy owned national rag, no less -- as indicia of newfound reality concerning race and its impact on medicine. [/color]
[SIZE=3]Race plays role in drugs' effectiveness[/SIZE]
Brad Evenson
National post
Tuesday, February 25, 2003
With the cracking of the human genetic code, it has become fashionable in recent years to declare that race is a meaningless concept, given that all humans share 99.9% of the same genes. But the discovery that an experimental AIDS vaccine seems to protect blacks and Asians much better than whites reveals one of medicine's dirty little secrets: Pills are not colour blind.
Many drugs that work splendidly for Europeans offer little benefit to people of other ethnic origins, and vice versa. One of the best-known Canadian examples occurred during a tuberculosis epidemic in the 1950s. All patients received three drugs, including one called isoniazid. But a large number of Inuit patients had a genetic quirk that caused them to break down the drug before it could destroy the TB bacteria. Many died; others developed drug-resistant TB strains that later infected others.
"To ignore race under such circumstances is practically akin to withholding treatment," according to U.S. psychiatrist Sally Satel, who has written extensively on the topic of race and medicine.
[color=blue]Read, legally actionable cause.[/color]
The decoding of the human genome in 2001 led many observers to believe race was a social construct, not a biological reality. Genome scientist J. Craig Venter said: "It is disturbing to see reputable scientists and physicians even categorizing things in terms of race."
**Dr. Venter's research showed genetic proof that most humans are nearly identical and are not divided into discrete groups based on race.
But people who study drugs don't buy this argument.**
"Relying on genetic similarity is a great mistake," said Werner Kalow, professor emeritus in the department of pharmacology at the University of Toronto. "Humans and chimpanzees are said to have more than 90% identical genes. And yet, nobody can deny that there are differences."
Skin colour can be a telltale sign -- or surrogate -- of a genetic difference of life-saving importance. For example, Dr. Kalow said up to 7% of whites do not produce an enzyme called CYP2D6 due to a gene mutation. Although the mutation doesn't cause illness, it affects the metabolism of up to 70 drugs. It prevents codeine from providing pain relief, affects beta blockers used for high blood pressure, and renders many psychiatric medications ineffective. But only about 1% of people in Asia and Africa have this CYP2D6 deficiency.
One of the most controversial studies has involved black patients with heart disease. In 2001, the U.S. Food and Drug Administration gave its approval for a clinical trial of a heart drug using only black patients. Historically, most drugs were tested on white males. But blacks, who are twice as likely as whites to suffer heart disease and twice as likely die from it, do not respond well to the same popular drugs as whites. So when the drug BiDil proved superior to beta blockers and ACE inhibitors in controlling blood pressure and heart failure in blacks, its makers proposed a blacks-only test. White patients got no benefit from the drug. Many commentators were angry, saying BiDil would be marketed as a "black drug."
Race may be a crude predictor of how a drug will respond, BiDil's supporters argued, but that doesn't mean doctors should ignore it.
Until now, scientists had not seen any important differences in the way vaccines affect the immunity of different racial groups. But some prominent scientists concede it's a possibility. For example, Francis Plummer, a renowned University of Winnipeg researcher, identified a group of prostitutes in Kenya who seem to be naturally resistant to HIV, despite repeated exposure. He suspects blacks may harbour some important differences from whites in their immune systems.
[color=blue]When the dim whites are extinguished, or nearly so, the progeny of the above ladies will constitute the vanguard of whatever remains of the still biologically viable African race.[/color]
"The population of Africa, their genetic background, has been shaped by different infectious diseases than has shaped the Caucasian population, so it's conceivable that there are differences," said Dr. Plummer, scientific director of the Canadian Science Centre for Human and Animal Health microbiology lab in Winnipeg.
He urged caution in interpreting the AIDSVAX findings that blacks who took the vaccine had almost 80% fewer HIV infections than blacks who took the placebo. Whites in the study had less than 4% protection from infection.
"I think we have to view [it] with a lot of skepticism," said Dr. Plummer, pointing out the sub-group of blacks in the study was very small.
[url=http://www.nationalpost.com/home/story.html?id={735663B0-AE99-4948-8DBF-570BC783D41D}]National Post[/url]
[color=blue]Simply, owing to the recent snowstorm of distressing medical news, which makes laughable the notion or racial non-relevance, no other approach is possible. The much publicized story of a Black girl dying duo to implantation of organ dependant on the wrong blood type (Note: black populations favour O, whites A, and Asians B.), the silly female lawyer trolling for an organ in China to save her adopted daughter because organ impoverished US lacks the right genetic stuff, etc. Henceforth, race will be found to have meaning for the medical community ââ¬â voluntarily or otherwise, for the coming lawsuits will make an impression and make believers of the ignorant. [/color]