Gallo’s new AIDS vaccine to begin human trials

Scientists believe that the best chance to end the HIV pandemic is still the development of a vaccine, however, researchers say the biggest challenge is the inability to develop antibodies that can handle the large amount of variability of HIV.

The HIV virus mutates endlessly to escape the immune system. And at last, after 15 years of concrete research, a newly developed AIDS vaccine is now about to be used in clinical trials. In the three decades since Dr. Robert Gallo made his breakthrough, more than 100 AIDS vaccines have been tested with limited success. It then transitions, exposing hidden parts of its viral envelope, which allow it to bind to a second receptor called CCR5. Once HIV is attached to both these T-cell receptors, it can successfully infect the immune cell and replicate itself.

The magazine explained that the vaccine, called “the full-length single chain vaccine”, “contains a version of HIV’s surface protein, gp120, engineered so that it links to a few portions of a protein called the CD4 receptor”. The antibodies stimulated by the vaccine shall detect the surface protein of the virus and block the virus from binding with CCR5 to halt the infection before it develops into AIDS. Testing for effectiveness will come later, and Gallo is already tempering expectations. But extensive testing has been done in monkeys so far with positive results.

“Was anything a lack of courage?” Gallo asked Science. “Sure”.

But the researcher also acknowledged that he and his team took more time to bring the vaccine to trial because “We wanted more and more answers before going into people”. It is being held in collaboration with Profectus BioSciences, a biotech that recently spun off from IHV. The development of the vaccine is being led by IHV’s George Lewis, whose team includes Antonio DeVico and Timothy Fouts. According to the Baltimore Sun, only one study-in 2009 in Thailand-came close to being effective enough for widespread use, and that only protected one-third of patients.