AIDS vaccine on the horizon?

[El_Machinae]

OK so I read this again. Can someone explain this to me:

Does that mean it wouldn't prevent someone from getting HIV via IV injection? Or through the blood via another means? I.e. does "mucosal" mean it only prevents transmission through mucus?

IIRC, simian research on HIV is difficult, because they respond quite differently than humans do to HIV. And other animal trials are nearly useless. It's a fairly human-specific disease.

I think you're correct, their tests of transmission must have involved exposing mucusal skin to HIV, and then later testing to see indicators in the blood. The antibody rests inbetween the skin and the blood, and prevents infection there. It does not seem to prevent blood-caused infections.

How do you conduct human trials of a vaccine? Do they really intentionally infect people with full blown HIV after they receive the vaccination?

A phase 1 clinical trial is a safety trial, so they would vaccinate volunteers and watch them for negative indicators.

Phase 2 is a small efficacy trial. In these, a larger group of volunteers is given either placebo or the vaccination, and then they're loosed into the world to see what happens. There was a big disappointment last year, when it was shown that an HIV vaccine caused an increase in HIV rates among its patients (i.e., rates higher than seen with placebo). With HIV, it gets confusing, because you'd think that in the process of getting volunteers, you'd be selecting for people who're wise enough to avoid HIV exposure. I guess healthy at risk people will be chosen for the study and then monitored.

 

[illram]

IIRC, simian research on HIV is difficult, because they respond quite differently than humans do to HIV. And other animal trials are nearly useless. It's a fairly human-specific disease.

I think you're correct, their tests of transmission must have involved exposing mucusal skin to HIV, and then later testing to see indicators in the blood. The antibody rests inbetween the skin and the blood, and prevents infection there. It does not seem to prevent blood-caused infections.


A phase 1 clinical trial is a safety trial, so they would vaccinate volunteers and watch them for negative indicators.

Phase 2 is a small efficacy trial. In these, a larger group of volunteers is given either placebo or the vaccination, and then they're loosed into the world to see what happens. There was a big disappointment last year, when it was shown that an HIV vaccine caused an increase in HIV rates among its patients (i.e., rates higher than seen with placebo). With HIV, it gets confusing, because you'd think that in the process of getting volunteers, you'd be selecting for people who're wise enough to avoid HIV exposure. I guess healthy at risk people will be chosen for the study and then monitored.

Interesting, thanks. If this vaccine does not prevent blood transmission, it seems like it is missing a major means of spreading the disease. E.g. injection drug users, anal transmission, even some vaginal transmission...(I guess anything is better than nothing though?)

Also interesting about the human trials. Seems like they would take a very long time to come to fruition. And if the vaccine only works on one method of transmission, seems like you would have to find some way to weed out those who got the disease via blood? Seems like that would complicate things. I mean, vaginal sex can infect you either via blood through tearing or through mucus. How would they know? Or you could have someone with multiple risk factors, i.e. lots of unprotected sex with new partners and frequent injection drug use...how would they differentiate? Can you tell by the type of infection?

 

[emzie]

IIRC, simian research on HIV is difficult, because they respond quite differently than humans do to HIV. And other animal trials are nearly useless. It's a fairly human-specific disease.

Animal trials of treatments are pretty useless, yes. However, studying the differences between SIV and HIV and the differences in specific proteins that inhibit HIV in apes has lead to promising avenues of research.

 

[El_Machinae]

No, Illam, I don't think you can tell how the virus was transmitted, though I suspect that mucus will still coat microtears during intercourse. But a vaccine is really useful for reducing levels of a disease, even if the vaccine is not perfect, because a few percentage points difference in susceptibility really comes out long term.

 

[Abaddon]

AIDS vaccine on the horizon?

Doesn’t the horizon always move away exactly as fast as you move toward it?

Sounds about right

 

[Sharwood]

I've been hearing about potentially promising cures for AIDS for the majority of my life and as of yet none have panned out. Not to be a party pooper but I'll believe it when I see it.

This. An AIDS cure/vaccine is on the books every six months or so. Same with cancer.

@Mowque: Watch Eddie Murphy's Raw. The next STD involves fire shooting out of your penis.

 

[GoodGame]

Problem is, someone has to test it when it moves well beyond phase I.
Phase I just tests that the vaccine doesn't have side-effects in humans.

A reasonable phase II/III would have uninfected volunteers receiving the vaccine, followed by a dose of HIV. Sounds like fun, comrade?

http://en.wikipedia.org/wiki/Clinical_trial#Phase_IV

It is interesting that the company took a different approach to procurring antibodies, though.


But what El Mach said. This vaccine might actually be some good as a co-treatment for an AIDS patient, to at least get viral levels downward, and circumvent the problem of HIV attacking the T-helper cells which downregulates immune response against HIV.

 

[El_Machinae]

They won't infect people with HIV for phase II

 

[GoodGame]

Why not? That'd be a select group. Though I guess it'd really depend on what use the vaccine is being marketed. As a true prophylactic vaccine, or as a treatment for HIV-infected people.

 

[emzie]

Why not? That'd be a select group. Though I guess it'd really depend on what use the vaccine is being marketed. As a true prophylactic vaccine, or as a treatment for HIV-infected people.

You test the vaccine by giving it to people who will very likely be infected... places like the south of Africa where the disease is truly an epidemic. You then twiddle your thumbs for a while and subsequently test people who received the vaccine.

 

[GoodGame]

That's a very weak study basis. I'd be surprised if it'd be allowed to advance in trial phase.

 

[emzie]

That's a very weak study basis. I'd be surprised if it'd be allowed to advance in trial phase.

The alternative being find volunteers to try to infect with HIV?

 

[GoodGame]

It would generate verifiable fact that way. The alternative is just trend analysis of the at risk population. Can a study really claim that they account for all variables to the FDA's satisifaction just by 'twiddling your thumbs for a while'? For instance, what if the at risk population actually experiences a lower risk than prior history, resulting in a false sense of effectiveness for the vaccine.
Not trying to downplay the usefulness to an infected population, but I would not want to claim or underwrite a product marketed for uninfected people on an inferred trend analysis.

 

[emzie]

It would generate verifiable fact that way.

Well actually, it wouldn't necessarily generate verifiable data. You can't infect someone with HIV just because you want to. Even a litre blood transfusion from an HIV-positive donor isn't a death sentence... it carries a 90% chance of infecting the recipient.

And while that's much higher than the infection rate in parts of Africa, it's still not fool proof. I'm not the best with maths, but I can't see why you wouldn't be able to get similar results between group A with a 30% chance of being infected and group B with a 90% chance, where group A is being tested on thousands and B is being tested on a handful of volunteers.

The alternative is just trend analysis of the at risk population. Can a study really claim that they account for all variables to the FDA's satisifaction just by 'twiddling your thumbs for a while'? For instance, what if the at risk population actually experiences a lower risk than prior history, resulting in a false sense of effectiveness for the vaccine.

What do you think they're doing now? They test preventative measures on populations with a high risk of contracting HIV. The gel that helped stop HIV from entering through mucus membranes was tested on prostitutes in India for example. It's not fool proof, no, but it's a whole lot more ethical than intentionally trying to infect people with HIV.

 

[El_Machinae]

You compare your treatment group with the control (placebo) group. You'd think that both groups would show reduced infection rates compared to the community (since they've been educated about HIV during the study). A malaria vaccine would be tested the same way.

Like I mentioned upthread, a recent study was terminated when they found that the treatment group was showing to be showing worse infection rates over the placebo group.

 

[Fr8monkey]

There will be no cure for AIDS (or anyother deadly disease) because the Drug Makers make too much money on drugs keeping you alive. You don't make money on 'curing' people

 

[Neonanocyborgasm]

There will be no cure for AIDS (or anyother deadly disease) because the Drug Makers make too much money on drugs keeping you alive. You don't make money on 'curing' people

There is always money in something that someone will buy. No matter what someone is paying to treat a chronic illness, they will pay any amount more to cure it. And there are always entrepeneurs eager to reap profit, especially knowing that it involves stealing profit from already profitable corporations, such as pharmaceuticals. That is just simple capitalism.

Be that as it may, I think this OP is probably a hoax. I took the liberty of examining the CROI 2009 program (it's available online) and there's no mention of any such presentation by Mymetics. The study, if it even happened, actually concluded in Sept 2008, so it's not news. I also get a digest of medical news, and have heard nothing about this, then or recently.

 

[Fr8monkey]

So if there is a complete cure but costs $500,000, don't you think the people who cant afford it wouldn't riot? Not many could get the cure, so the pharm. companies would make more in the long run by keeping people alive for another 20 years.

It's like the old myth of the 200 MPG carbourator... The car companies wouldn't deploy it 'cause they cant make money on good gas milage.

 

[El_Machinae]

Fleury has quite a few abstracts at the conference. Though the CNN.money story is an abstract put forward by the company, and I don't think CNN is vetting it.

 

[Sharwood]

There will be no cure for AIDS (or anyother deadly disease) because the Drug Makers make too much money on drugs keeping you alive. You don't make money on 'curing' people

"They're still pissed about curing Polio!"

If there's money to be made in a cure, they'll look for it. Now, if they were a company that made more without the cure than they would with it, they mightn't bother looking, or more likely would develop one and sit on it, but if there's money to be made, people will try to make it.