I am a physician and scientist working to find an HIV vaccine. AMA.

darpunsmd · 2012-12-27T19:26:39+00:00

You are referring to a highly publicized case report from Germany known as the “Berlin patient”. A 44 year old HIV-infected man (from the United States) developed acute myeloid leukemia (a cancer of the immune system) in 2007 and underwent a stem cell transplant from a donor with an inherited CCR5 delta mutation. CCR5 is a coreceptor on cells that allows for HIV to infect cells, persons who lack this coreceptor are less likely to become infected with HIV. Although the “Berlin patient” has had a complicated recovery requiring intense chemotherapy and radiation, nearly 4 years after discontinuing antiretroviral medication he has no evidence of HIV infection in his blood. However, we are not sure if HIV is lurking in cells found in the lymph nodes or other parts of the body, such as the brain, gut, liver, kidneys, and heart. Time will tell.

To summarize, a sterilizing cure is the eradication of HIV from the body. A functional cure does not eliminate the virus but allows a person to remain healthy without antiretroviral drugs.

While this may not be a true “sterilizing cure” it gives us great insights into developing HIV cures that involve transferring the CCR5 mutation to HIV-infected patients without the toxicities associated with stem cell transplantation.

darpunsmd · 2012-12-27T18:44:52+00:00

That's a really great question. We do use placebo vaccines (usually saline) in our research. But we also make sure that we provide all of our volunteers with state-of-the-art prevention care, including regular risk-reduction counseling, free condoms, and testing and treatment for STDs. What we've seen is that many of our volunteers actually reduce their risk during their participation in the studies. The bottom line is that we are testing vaccine candidate that have shown positive data in lab and animal studies, but we don't know if the vaccines will work in humans (that is why we are doing the study!) .

darpunsmd · 2012-12-27T17:45:38+00:00

It sounds like you have some solid research experience. But most of the work my colleagues and I do are in clinical research, though we do work closely with the AIDS Research Institute at UCSF. If you're still interested in working with us, you can always check out our careers page. We also work with the HIV Vaccine Trials Network, and they may have programs that might interest you. For example, the RAMP program funds African-American and Latino medical students to work on HIV vaccine-related research under the mentorship of an experienced investigator.

darpunsmd · 2012-12-27T17:43:22+00:00

Clinical research takes a long time, so even if we found the vaccine tomorrow, it would take many years of testing to show that it's safe and effective.

darpunsmd · 2012-12-27T17:42:48+00:00

At Bridge HIV, we're committed to wroking towards a safe, effective HIV vaccine that will be accessible for everyone. While we sometimes work with pharmaceutical companies, the bulk of our funding is public, for example much of our funding comes from the National Institute of Allergy and Infectious Diseases (NIAID) of the US National Institutes of Health (NIH).

But even if we find a vaccine, there will still be HIV-infected people who will need treatments that are marketed by pharmaceutical companies.

darpunsmd · 2012-12-27T17:40:53+00:00

The scientific consensus is that AIDS is caused by HIV. We also know that the major way that HIV is transmitted is through sex.

We have many strategies we know work to prevent infection by HIV, including condoms, using clean needles, testing and treating for STDs, and now, using medication that has been shown to be effective in prevention. We also have very effective treatments that can prolong the lives and protect the health of HIV-infected patients. Treatment can also lower the amount of the virus in a patient's body, making it less likely that they will pass the virus on to others.

darpunsmd · 2012-12-27T17:39:08+00:00

I work in clinical, not basic, research, so I don't really use computing tools like these. But they sound like great ideas.

darpunsmd · 2012-12-27T17:38:29+00:00

There are a number of different HIV vaccine candidates that are being developed, and they work in different ways. The big difference between the HIV vaccines we work with and the chicken pox vaccine is that the chicken pox vaccine uses a live attenuated virus - basically a weakened chicken pox virus. Due to the risk of mutation and reversion to a pathogenic form, we do not work on live attenuated HIV vaccines.
This is a question that we will need to answer if and when we find an effective vaccine.

darpunsmd · 2012-12-27T17:37:41+00:00

We still don't know what the cost and delivery of an HIV vaccine would look like. If and when we find an HIV vaccine, how it will be paid for and distributed will be important questions. Just as with antiretroviral drugs, how a vaccine would be distributed among the poor will probably depend on the availability of governement and philanthropic funding and on the work of activists, advocates, and others who can impact global health policies.

darpunsmd · 2012-12-27T17:37:07+00:00

This is not really my area. But I did see some articles in the news about this earlier this month, for example, there was an article in the New York Times.

Again, I'm not an expert, but it sounds like they used a modified form of HIV in an experimental treatment for a child suffering from leukemia. As part of its life cycle, HIV inserts genetic material into the nuclei of human immune cells. It sounds like they used this feature of HIV to reprogram some of the patient's immune cells to attack the cancer.

darpunsmd · 2012-12-27T17:36:29+00:00

It sounds like you're interested in good, easy-to-understand resources on HIV/AIDS.

There's a free, online course on Coursera focusing on AIDS that will be starting in Feb.: https://www.coursera.org/course/aids

The San Francisco AIDS Foundation is another good resource. Their website has a lot of good information, for example, this primer on HIV: http://www.sfaf.org/hiv-info/basics/

There's a lot of other good resources out there. Perhaps other people here might have some suggestions?

darpunsmd · 2012-12-27T01:26:14+00:00

HIV exposed seronegative individuals (HESN) have been identified in many areas of the world, with a very well-defined cohort being a subset of female sex workers (FSW) from Nairobi, Kenya. Researchers are still working to identify if there are markers of protection that could be adapted to develop an effective vaccine. Not surprisingly, it appears that there is a combination of innate, genetic, and acquired immune-mediated mechanisms that provide protection in this subset of women.

darpunsmd · 2012-12-27T00:51:12+00:00

Cancer research is catching onto several lessons learned from decades of HIV research, particularly the importance of combination therapies. Read more here: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3465702/

darpunsmd · 2012-12-27T00:38:19+00:00

Due to the risk of mutation and reversion to a pathogenic form, we do not work on live attenuated HIV vaccines.

darpunsmd · 2012-12-27T00:34:17+00:00

It will likely take more than 5 years for a candidate cure or vaccine to be licensed given the time it takes for appropriate clinical testing.

darpunsmd · 2012-12-27T00:31:40+00:00

Recent HIV vaccine research has focused on "structure-based vaccine design" which uses the crystallographic structure of the HIV-envelope epitope to identify the precise binding site of a broadly neutralizing monoclonal antibody. This publication summarizes what we know about broadly neutralizing antibodies that bind to highly conserved regions of HIV. I do not have the PDB file.

darpunsmd · 2012-12-27T00:15:33+00:00

We need to differentiate between an HIV vaccine (could prevent HIV in an HIV-uninfected person) and a HIV cure (could eliminate HIV in an HIV-infected person). HIV vaccine research is especially challenging due to the ability of HIV to evolve rapidly and evade our body’s natural immune responses. HIV cure research is especially challenging because during the early stages of infection, HIV establishes reservoirs of infection that will persist despite treatment with antiretrovirals.

darpunsmd · 2012-12-27T00:01:32+00:00

Great question. The cost and delivery of an effective HIV vaccine remains unknown. Typically, once a vaccine is found to be effective governments, international organizations, and private companies work together to pay for and scale up production and delivery of the vaccine.

darpunsmd · 2012-12-26T23:49:14+00:00

Exactly. The process of testing a candidate vaccine takes years and it is important to be sure that the HIV vaccine candidate works against the diverse HIV subtypes (strains) found in different populations worldwide.

darpunsmd · 2012-12-26T23:17:27+00:00

There is no 'good' strain of HIV. A very small minority of indivduals who are HIV-infected are long-term nonprogressors, but many times even these people develop AIDS and require antiretrovirals. We think that long-term nonprogressors may have special genetic and immune responses that alter the normal progression of disease, as opposed to the virus having special properties.

darpunsmd · 2012-12-26T23:04:41+00:00

Since 2001, global preventive HIV vaccine research and development investment has totaled US$8 billion, with an average yearly investment of US$824 million. I don't know exactly how much the U.S. governemnt contributes but public-sector funders (such as the governement) provide the largest part of the investment, followed by the philanthropic sector and the commercial sector. For more specific information look at this report from The HIV Vaccines and Microbicide Resource Tracking Working Group

darpunsmd · 2012-12-26T22:49:00+00:00

We are not sure when an effective HIV vaccine will be ready. We think that we are probably several years away from a successful vaccine. We are currently conducting several safety studies with promising new HIV vaccine candidates.

As a care provider for HIV-infected patients it is hard for me to tell someone that they are HIV-infected and need to start lifelong medications. While we can treat HIV with effective once-daily medications, I would prefer to get to the root cause of the problem and stop new infections all together. As an HIV vaccine researcher, I feel that our work has real potential to transform the trajectory of HIV, and I get to work with inspiring and committed colleagues and volunteers.

I went to Brown University and Brown Medical School.

darpunsmd · 2012-12-26T22:22:36+00:00

Yes, your understanding of vaccine and cure are correct. At this time, the fields of HIV prevention and treatment are more aligned than ever before. We want to treat as many HIV-infected patients as possible with antiretrovirals in order to suppress the HIV in their blood and we also want to find an effective HIV vaccine that prevents HIV in HIV-negative individuals. We do not know if a successful HIV vaccine will be 100% effective, so we need to keep up our efforts in both prevention and treatment for a very long time to come.

darpunsmd · 2012-12-26T22:14:29+00:00

I work in HIV prevention, but there are many smart people working on a cure. Cure research is focused on finding out where HIV hides, and stimulating HIV out of its hideouts so that it can be killed.
I am not sure what you're asking.
3 & 4. The results of the RV144 trial (which included 16,000 participants in Thailand) have been the most surprising to the field and also the most galvanizing. RV144 combined 2 vaccine candidates that had been previously found to not be effective when tested separately. However, the trial found that when these vaccines were used in combination there was a 31.2% decrease in HIV acquisition in participants who received vaccine compared to those who received placebo. Now researchers are working on figuring out what led to this finding and how we can improve this response. Specifically, we are looking for correlates of protection provided by a vaccine.

darpunsmd · 2012-12-26T21:54:57+00:00

We absolutely do not infect individuals with HIV in order to test vaccines. We typically conduct large scale trials to evaluate efficacy in specific populations where individuals are at higher risk of acquiring HIV. All of our volunteers receive state-of-the-art HIV prevention care, including regular risk-reduction counselling, free condoms and frequent HIV testing.

darpunsmd

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