HIV/AIDS prevention and treatment underway in San Diego
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July 25, 2012 1:08 p.m.
Dr. Davey Smith, Associate Professor of Medicine, UC San Diego
Dr. Sheldon Morris, Assistant Professor of Medicine, UC San Diego Antiviral Research Center
Related Story: Local Efforts Underway To Prevent and Treat HIV/AIDS
CAVANAUGH: This is KPBS Midday Edition. I'm Maureen Cavanaugh. The 19th annual international AIDS conference is underway in Washington DC. And there continue to be promising developments in treatments as researchers learn more about this complex disease. Some of those advances have connections to research done here in San Diego. And along with the high-tech advances, there are also low-tech, common sense efforts being made to slow down the transmission of HIV. I'd like to welcome my guests, KPBS health reporter, Kenny Goldberg.
GOLDBERG: Hi, Maureen.
CAVANAUGH: Doctor Sheldon Morris with the UCSD antiviral research center. Welcome.
MORRIS: Thank you.
CAVANAUGH: And Davey Smith is associate professor of medicine at UC San Diego. Doctor Smith, hello.
SMITH: Hello, thank you.
CAVANAUGH: Kenny, let me ask you about these AIDS conferences. What goes on there?
GOLDBERG: Well, they're just really fantastic. They're a world meeting place of all the researchers, all of the advocates, all the drug merchandisers, you name it. If they're involved in HIV, AIDS, in any kind of way, they're there. And it's an incredible place to go as a reporter because you have this repository of this knowledge. And anybody who's anybody in the field, you can interview and find out the latest research. It's really quite something.
CAVANAUGH: Has the message of HIV/AIDS changed at these conferences over the years?
GOLDBERG: It definitely has. In the early days, HIV and AIDS were almost a complete mystery. Now we're talking about the disease has already been turned into a chronic illness like diabetes, and now we're even talking about a possible cure in the not too near future. I don't know how realistic that is, but they're actually talking about it.
CAVANAUGH: Have they gotten more optimistic?
GOLDBERG: Oh, yes. Absolutely. And I'm sure these gentlemen can talk about that. But the research is coming up with so many interesting ways to decipher the illness and different treatment methods that drugs now are credibly effective. So somebody with HIV, if they're caught early enough, it's a chronic ills. They can live a GOLDBERG and healthy life.
CAVANAUGH: Doctor Morris, one of the thingses we've heard a lot about this year regarding HIV/AIDS is truvatta research. You're the study chair of Truvada research at UCSD which was recently approved by the FDA for people who do not have HIV. Remind us what this drug does.
MORRIS: Well, this is a drug that we've used as the backbone of HIV treatment for those people infected with HIV for a GOLDBERG time. It's one of our most popular drugs. And what they found over a number of studies is that people that do not have HIV but are at very high risk of HIV, if they take this drug, will actually reduce their chance of getting HIV and varying estimates from about 44% to up in the 70% range depending on your study. So the main focus right now is with the approval from the FDA, it's now about how do we use this drug in preventing HIV? And there is some guidance around who the people are who should get it. But how do we implement these new and effective tools that we have for prevention?
CAVANAUGH: Would someone who is at high risk, perhaps whose partner was HIV positive began taking truvad Awould they have to take it every day for the rest of their life, so to speak?
MORRIS: Well, people take it, it works, if they don't take it, it doesn't work when you're talking about people who are, say, one person does not have HIV, and the other does, this is called a discordant partnership, we also would emphasize that that HIV positive person, if they take antiviral medication that suppresses their virus, the chances of transmitting to their partner is reduced 96%. So this is over and above that. As GOLDBERG as their exposure exists, they would have to continue to take the drug.
CAVANAUGH: How different is Truvada from an antiHIV vaccine? I understand probably the vaccine, you'd only have to take once or in a series of injections. But what are the different mechanisms?
MORRIS: Well, Truvada is a combination of two different antiretroviral drugs. It works by stopping HIV replication before it even gets started, really. Maybe the virus may actually get to the mucosa, but this drug is probably stopping it from replicating. The vaccine would be targeting epitopes on the virus and allow the body to clear the virus if it does enter the body. But the problem is that the vaccine -- we don't have an effective vaccine. The vaccines that have been shown -- some efficacy are far from adequate. And in the developmental process, we don't have a good candidate for vaccines. We'd all love to have a vaccine that would be the 1-time shot. And even then, there's challenges. If you think about circumcision, which is another profoundly effective method to reduce HIV transmission in developing countries particularly with heterosexuals, the implementation of that has been fraught with difficulty. And that's a 1-time procedure.
CAVANAUGH: Getting it back to San Diego for a minute, I read that there is new research being funded right here to develop a vaccine. Isn't there, Kenny?
GOLDBERG: There is. It's a new federal grant from the NIH, like, $77 million that's going to be centered at the Scripps research institute in La Jolla. But as my colleague was saying, the search for an HIV vaccine is incredibly difficult because the virus itself is so illusive. It makes the flu virus look like a picnic. And one of the challenges as I understand it is the HIV virus is different in San Diego as it is in Bangkok Thailand, so it's incredibly challenging.
CAVANAUGH: This very advisor is part of your research, isn't it, Davey Smith? You are trying to track the spread of the virus in our region. How are you doing that?
SMITH: That's correct. It's just like what Kenny said. Every different region across the world has a different virus, basically. It has a genetic difference in Thailand, the United States, from Canada, but even within the individual, if they're infected they have a unique HIV sequence. And you can sequence the virus and tell who that particular strain is associated with and how related it might be to other individuals within a community. And based on that information, you can build a transmission network.
CAVANAUGH: So when you build a transmission network, can you identify individuals who may be spreading the disease?
SMITH: We don't identify individuals. But we can see where there are highly related sequences that start to cluster together, and we can see them expanding and growing quickly. And once we have that information, that tells us there might be a subepidemic occurring. And my project is to identify those as close to real-time as possible and develop prevention for those.
CAVANAUGH: So you would be able to say there's something happening in this region; we have to go in there and find out what the at-risk population is doing. Is that the idea?
SMITH: That's pretty close. It's not just region, but it might be associated with other factors like an outbreak associated with syphilis transmission or gonorrhea. So then our prevention effort might be around gonorrhea and syphilis and to get individuals who might come in with those diseases test forward HIV as quickly as possible. And then that would be associated with that cluster. Or also looking at substance abuse as well.
CAVANAUGH: I mentioned in the beginning we were going to be talking about high-tech and low-tech HIV/AIDS prevention. You did a story about efforts to prevent the spread of the disease among sex workers in Tijuana. Tell us how vulnerable this population is.
GOLDBERG: Well, they're incredibly vulnerable. That's probably because client comes down there, many from the U.S., and they want these sex workers to do things that they would never do with their partners here in the states. Real risky stuff we're talking about, plus the sex workers are offered more money to have unprotected sex or to do drugs with the clients. And because many of them are drug users themselves, they're desperate for their fix, they take the money, and so we have a lot of risky behavior going on in Tijuana and Ciudad Juarez.
CAVANAUGH: What does the program consistent of?
GOLDBERG: The study took a look at the concept of whether a brief intervention, a counseling session of 1/2 hour could change sex workers' risky behavior. So these women had a 1/2 hour session on safer sex practices, and a 1/2 hour session on safe injection practices. And they either got a lecture format or a more interactive thing where they were joining in and asking questions and taking part. And what they found is that the women who had either format of the intervention, had a 60% lower rate of new infections than women who didn't have it at all. And this was true in both Tijuana and Ciudad Juarez.
CAVANAUGH: Do researchers now say this program is working?
GOLDBERG: Right. And they found in terms of the safer injection practices, they found the rates of new infections were much lower in Tijuana than in Juarez, and they figured out the reason is because in Tijuana there's a much more robust clean syringe exchange program than there is in Ciudad Juarez. So the head researcher at UCSD came to this conclusion.
NEW SPEAKER: The bottom line is that if you're a city or a policy-maker that's making a decision on how to reduce injection risks for HIV, it's much more important to have coverage of sterile syringes through either needle exchange or pharmacies than it is to provide an intervention like this.
CAVANAUGH: Okay. Well, that is as I said the low-tech version of this. Doctor Morris, when we go to a drug like Truvada, it's very expensive, isn't it?
MORRIS: Yes it is. Certainly. Depending where it is, it could be up to $1,000 a month, in that ball park.
CAVANAUGH: I want to bring both you and doctor Smith in on this. We started talking about the world AIDS conference. And most of the world is not as rich as the United States. When you get to people in the developing world who have HIV or maybe even AIDS, what kind of resources do they have to be able to get access to a drug like Truvada?
MORRIS: Well, Truvada like I say has been around for a while and is the one thing we really like to use for the treatment. Even so, they're still using older drugs in Africa that give a lot of toxicity. So getting these drugs can be very difficult. And it really takes a cooperative effort, international effort, that involves countries to get-together, things such as the pep far program has provided, drug companies providing drugs for cheaper amounts. Generic companies coming from India and China to really try to get to a price point where a conserve if it so chose to follow that policy could maybe implement some of these things. But even then, it still becomes very difficult -- difficult for them when they do not have the physical resources for it.
CAVANAUGH: What level of thought is given to the research that you do and the drugs that are developed and the potential vaccine that might be developed? How that can be used across the nations of the world.
SMITH: Well, across the nations of the world, it's very interesting. That's one of the reasons we have the international AIDS conference. The vast majority of people who have HIV don't live in the United States. They live in subSaharan Africa. And that's where the least amount of resources are to treat the program. So pep far through the United States is probably the biggest life saver we have to get people who are actually on HIV medications. And there's been one very famous study last year and multiple studies showing if you treat someone who has HIV infection, that is the best prevention effort so they don't keep transmitting the virus forward. In our country, and also in Africa, are the biggest impediment to that is letting people know they actually have HIV infection. A quarter of the people here in the United States don't even know they have it. Just getting tested, linking those individuals to care, and those are probably some of the best prevention measures we have.
CAVANAUGH: So Mr. Morris, even with these remarkable advances that are taking place, it all goes back to getting tested?
MORRIS: Yeah. And I come from sort of an STD world too, are and the idea was also you treat the STDs and treat their partners, and that's how you control it. And this is sort of where we're going with HIV, really bringing people, testing them, and getting them -- but beyond that, you have to bring them into care, get them on drugs and have them take the drug so they're suppressed. And one of the presentations they're going to talk about today at the international meeting was about how maybe even people taking the drug, only about 70% of them may actually have suppressed virus. So there's a whole cascade of things that need to happen to go from diagnosing people to having and taking the drug and successfully controlling their HIV.
MAUREEN CAVANAUGH: It's a whole continuum.
CAVANAUGH: Thank you all very much.
MORRIS: Thank you
SMITH: Thank you.
GOLDBERG: Thank you.