Major Setback in the Search for an HIV Vaccine

Yesterday I took my 15 month old son in for his checkup and to get vaccine shots. I usually have a clear idea beforehand what shots he is due for and what he is being vaccinated against, whether it is the flu or measles and mumps. In fact, these vaccinations are so commonplace, that very few parents question what they are for or how effective they are. We simply trust that they do what they are intended to do, which is to protect our young children from diseases that could potentially be life-threatening. Parents don’t think of measles or rubella or of the time not so long ago before the vaccines when these diseases were responsible for claiming thousands of lives a year. Imagine if we lived in a world where a disease like AIDS had its own vaccine?

Since AIDS emerged in the 1980s, scientists and researchers have been madly scrambling to find a vaccine to stop or at least slow down the massive outbreak that is currently taking place in all parts of the globe. The creation of this miracle vaccine may take longer than anticipated, however, as two studies of the leading test vaccine had serious drawbacks. The field test results showed that the test vaccine did not shield participants from contracting HIV and might have actually put them in harm’s way by increasing their risk of contracting the virus. These trials which included voluntary participants from four continents were a heartbreaking end to what seemed a very promising development.

Robert Gallo, one of the initial discoverers of HIV, states, “This is on the same level of catastrophe as the Challenger disaster.” Phambili and STEP were the two trials that were stopped in September 2007. These trial vaccines were created from adenovirus type 5, a fairly common respiratory virus that was then weakened and filled with HIV particles. As the STEP studies progressed and researchers began realizing that the vaccines were not doing what they intended and might actually be doing more harm than good, they halted both the STEP and Phambili trials immediately.

Researchers have now begun wondering if these dire results will affect all future AIDS clinical studies. Scientists on the STEP trial have begun suggesting that in an unforeseen event, the vaccine seemed to make the participant’s immune system more prone to contracting HIV. Some fellow AIDS researchers have lost trust in the National Institutes of Health which provided the funding for the two failed clinical human trials. Ronald Desrosiers, a molecular geneticist, stated, “We simply do not know at the present time how to design a vaccine that will be effective against HIV.” At a Boston AIDS conference, he went on to state that he believes the NIH should steer clear from conducting any further human research and should instead fund only basic AIDS research. Still, other researchers including John Moore, an AIDS virologist, have offered a little more support, “I do not think that what happened in this trial is an example of scientists blindly rushing into dangerous things. In the general HIV-research community, I didn’t know anyone who said this was going to happen.”

Both the STEP and Phambili trials were going to have approximately 3,000 participants who were considered high HIV risks. Before the trial was stopped, STEP had already recruited volunteers in the Caribbean, Australia and North and South America. The vaccine was developed to create an environment where if previously vaccinated, a newly HIV-infected patient would have a less rigorous version of the infection. This would have hopefully helped an infected patient live longer and give them less chance of infecting others.