Injectable HIV vaccine shows promise

LONDON, July 21 (UPI) -- A British clinical trial of HIV vaccine demonstrates an approximately 90 percent difference in viral count in HIV-infected people, researchers say.

Gregory Stoloff, chief executive officer of Seek -- a privately owned biopharmaceutical company -- said this is the first time ever that a human immunodeficiency virus vaccine has shown such a meaningful result in a human clinical trial.

"The next step will be to progress this to final human trials and determine the optimum dose and dosing regime to further enhance the vaccine's efficacy," Stoloff said in a statement.

The development of an effective vaccine against HIV has been extremely difficult because the HIV virus constantly mutates, but the Seek's HIV-v vaccine targets only the conserved regions in the internal proteins of the HIV virus which remain constant across all HIV strains.

It is the first vaccine to generate both strong T-cell and antibody responses to eliminate HIV-infected cells and thus neutralize the HIV virus, Stoloff said.

With HIV-v, the immune system is primed to recognize and target only those regions within HIV proteins that are highly conserved and hence present in all recorded strains of this highly variable virus, Stoloff said.

Seek officials say it is expected in 2012-2013 there will be therapeutic Phase III trials, which will recruit HIV-infected patients whose viral-load levels will be monitored to determine the optimal dose and dosing regime. If approved, the vaccine could be available to patients in three to five years.