AIDS- ARE WE ANY CLOSER TO A CURE? WHY OR WHY NOT

By Deepu Nair

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AN INITIAL THOUGHT ABOUT THE ECONOMIC OUTLOOK

“From the point of view of the pharmaceutical industry, the AIDS problem has already been solved. After all, we already have a drug which can be sold at the incredible price of $8,000 an annual dose, and which has the added virtue of not diminishing the market by actually curing anyone.” – Barbara Ehrenreich.

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POSSIBLE OBSTACLES TO A CURE

Political obstruction by conservative circles who think a cure to AIDS, primarily a prophylactic cure to AIDS, will result in more promiscuity in society.

Pharmaceutical companies may decrease funding to trying to find a cure to AIDS as that would eliminate a huge market with recurring income.

The technical difficulties in finding a cure to AIDS (due to being caused by a virus).

The extremely diverse and quickly mutating HIV .

POSSIBLE SOLUTIONS TO THE PROBLEMS

The conservative circles against finding a cure to AIDS are currently miniscule and not enough to cause significant political obstruction. They can be ignored for the time being.

Though funding has gone down in trying to find a vaccine to cure or prevent AIDS, funding isn’t the biggest issue in finding a cure to AIDS.

The technical difficulties in finding a cure to AIDS are huge and imposing, but research may solve it.

The quickly mutating and diverse virus can be dealt with by attacking bodily aiding co-factors.

SO ARE WE ANY CLOSER TO A CURE?:THE DEVELOPMENTS

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AIDS VACCINE

One of the biggest hopes when it comes to the pursuit of curing AIDS is the development of an effective vaccine against AIDS.

In the early 90’s the AIDS vaccine effort was rather weak.

In 1997, when President Clinton claimed that it wasn’t a question of whether we will develop a cure to AIDS but when, there was a lot of optimism, but at the same time infectious disease experts had cautioned against the overt optimism.

AIDS VACCINE

In 1997, the International AIDS Vaccine Initiative (IAVI) received $186 million in funds to try to develop a vaccine, this amount burgeoned into 759 million by 2005.

However, very recently, the UN came out with a report that says the funding for finding an HIV virus is declining.

By the year 2000, the NIH had begun its own project to try to develop an effective vaccine against AIDS.

AIDS VACCINE

A vaccine was designed to empower the T-cells to attack the HIV more aggressively, but the chances that such a vaccine would prevent infection by the virus was very low. It failed.

In late 2004, trials were held for a different vaccine that carried partially dormant non-HIV viruses that had certain HIV genes. It failed clinical trials.

The fact that HIV can mutate incredibly quickly remains by and far one of the greatest obstacles towards achieving an AIDS vaccination.

AIDS VACCINE

A new T-cell stimulating vaccine was being explored as yet another kind of vaccine for curing AIDS. It was called “STEP” and it was developed by Merck. It failed clinical trials.

Tests on the vaccine by Merck and HVTN indicated a failure and it was publicized that it failed due to the lack of prevention of infection.

Later, It was discovered by the researchers at the Wistar Institute that the CD4 T-cells that were supposed to be stimulated really did not get activated and they didn’t expand either.

AIDS VACCINE

This recent discovery still keeps open the window for a miracle vaccine to AIDS.

An AIDS vaccine no matter how unsuccessful may be highly useful.

A vaccine that can prevent only 30% of infections, if given to 20% of those at risk, would prevent 5.5 million infections worldwide between 2015 and 2030.

A 70% effective vaccine given to 40% of those at risk would prevent 28 million infections in the same time span.

AIDS DRUGS

Unlike the vaccines that have been used for AIDS, drugs developed to suppress AIDS have been a much bigger success.

These drugs can drive HIV levels in the body so low as to be undetectable by standard tests.

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AIDS DRUGS

These more than 25 approved drugs have resulted in a longer and healthier life for patients however; they’ve also failed to provide a complete cure to AIDS.

As soon as the regimen of drugs may be interrupted the virus will bounce back to high levels in the blood.

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AIDS DRUGS

In order to accurately and better treat the HIV virus, the exact location of where HIV hides in the body needs to discovered and the virus has to be attacked in those regions.

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AIDS DRUGS

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oThe HIV virus like other viruses needs body cells to replicate however unlike other viruses it injects its genome into human cells, thus making more viruses each time the cell divides.

oThe powerful new drugs being developed for HIV tends to suppress the replication of HIV cells and thus appears to give the immune system plenty of time to eliminate the remaining HIV infected cells but still HIV continues to return.

HIV FUNCTION

It has been found that one of the places that these HIV viruses hide is the long-lived memory T-cell.

These seem to be the cells that get affected by ‘virions’ and often create the most viruses in infected individuals.

Besides T-cells though, the HIV virus is known to first infect Macrophages and take-up residence in them.

Studies have shown though that higher concentration of the drugs could suppress the replication of HIV in macrophages as well.

AIDS SHELTER LOCATIONS

Besides even the macrophages, the HIV virus seems to have some more shelters, where it may not be as active but it persists in these pockets in order to avoid destruction by the immune system or any form of drug.

The CNS (Central Nervous System), gastrointestinal tract, and the genital tract are some of these shelter locations.

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NEW PROPOSED SOLUTIONS

In order to attack such concealed viruses researchers have tried a new tactic of using compounds that would cause dormant infected T cells to divide and thus be more easily destroyed by antiretroviral therapy.

A few limited human trials have been conducted with this; however it has given mixed results.

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NEW PROPOSED SOLUTIONS

Yet another solution that is being tried is intensifying existing antiretroviral drugs with raltegravir (a new drug that targets a viral enzyme not hit by earlier drugs).

It has been found that doing so actually speeds up the rate of viral decay.

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NEW PROPOSED SOLUTIONS

Another solution being explored is either protecting the protein A3G (protein in macrophages and lymphocytes) or inhibiting Vif (Enzyme secreted by viruses that degrade A3G).

Being able to do either of these, will in theory make human beings resistant to AIDS.

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NEW PROPOSED SOLUTIONS

Yet another solution that is being investigated is the creation of integrase inhibitors that will prevent HIV from attaching to the molecular receptor CCR5.

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NEW PROPOSED SOLUTIONS

A genetic solution to AIDS is also being explored as a CCR5 gene allele has been discovered that confers immunity to AIDS in the homozygote form, and gives people a higher chance of survival in the heterozygote form.

A proposed method of curing AIDS is to destroy all existing HIV cells and then run a blood transfusion from a donor who is homozygous for the mutant CCR5 allele in order to prevent any future infections.

NEW PROPOSED SOLUTIONS

Other solutions drawn from genetic research is to administer chemokines (suppressive factors that could block M-tropic HIV) or to inject CCR5 to induce the body’s CCR5 binding antibodies to act on them.

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THE AMAZING CASE

In an amazing case in 2008, a bone marrow transfusion of a 42 year old American patient in Berlin who was being treated for leukemia resulted in the curing of his AIDS condition.

Normally after stopping to take AIDS medication HIV bounces back in huge numbers in days or weeks however for over 600 days after ceasing to take AIDS medication, not a trace of HIV was found in his blood.

THE AMAZING CASE

His doctor Gero Hütter had deliberately given him a blood transfusion from a donor who is homozygous for the mutant CCR5 allele, thus proving the above suggested solution successful in a clinical trial.

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NEW PROPOSED SOLUTIONS

Another proposed solution for a prophylactic (preventative) vaccine to AIDS is using catalytic anti-HIV lgs in a vaccine.

Yet another solution that is being discussed is telomerase induction in T-cells which will effectively make the T-cells immortal (by retarding or preventing cellular senescence) and thus will ensure the presence of a greater amount of T-cells to combat both HIV infected viruses and other pathogens as the immune system wouldn’t be so susceptible without it.

THE BIOETHICS ANSWER

After all these developments, Yes! we are closer to a cure.

There has been one documented success in a human being.

There are more powerful anti-retroviral drugs that can be used.

There are several new proposed solutions to AIDS that hold significant promise.

RESOURCES USED Effros, R B (2006, December 6). Telomerase induction in T cells: A cure

for aging and disease. Retrieved July 26, 2009, from ScienceDirect College Edition Web site: http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6T6J-4MM25XY-1&_user=4143805&_coverDate=05%2F31%2F2007&_rdoc=1&_fmt=&_orig=search&_sort=d&_docanchor=&view=c&_acct=C000062368&_version=1&_urlVersion=0&_userid=4143805&md5=608a6e5bc7ea095b4ecd404d0851c43a

Ehrenreich, Barbara (1991). The worst years of our lives. New York City, New York: HarperCollins.

Hildegund, C J (2009, July 20). Penn-Wistar team gains insight into HIV vaccine failure. Retrieved July 26, 2009, from The Wistar Institute Web site: http://www.wistar.org/news_info/pressreleases/pr_07.20.09.htm

“In search of AIDS-Resistance Genes”, O’Brien, Stephen J., Dean, Michael, Scientific American, September, 1997, pages 44-51

Minkel, J R (2007, December). Where is the AIDS vaccine?. Retrieved July 26, 2009, from Scientific American Web site: http://www.scientificamerican.com/article.cfm?id=where-is-the-aids-vaccine

Planque, S (2008, April). Catalytic antibodies to HIV: Physiological role and potential clinical utility. Retrieved July 26, 2009, from ScienceDirect College Edition Web site: http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6W8V-4SD1B9V-1&_user=4143805&_rdoc=1&_fmt=&_orig=search&_sort=d&_docanchor=&view=c&_acct=C000062368&_version=1&_urlVersion=0&_userid=4143805&md5=471f6c0c364bd3900073bf880dfbf1c0

RESOURCES USED Laurance, J (2009, February). Gene therapy offers hope

of cure for HIV. Retrieved July 26, 2009, from The Center for Genetics and Society Web site: http://www.geneticsandsociety.org/article.php?id=4523

UN, (2009, July 20). New UN-backed report finds declining funding levels for HIV vaccine research. Retrieved July 26, 2009, from UN News Centre Web site: http://www.un.org/apps/news/story.asp?NewsID=31516&Cr=HIV&Cr1

Stevenson, M. (2008, November). 25 Years Later: Can HIV be cured?. Retrieved July 26, 2009, from Scientific American Web site: http://www.scientificamerican.com/article.cfm?id=the-aids-vaccine-search-goes-on