Nearly 7,400 people a day are infected with HIV. An AIDS vaccine with 50% efficacy given to 30% of the population would avert 5.6 million new infections in low and middle income countries between 2015 and 2030.
Most initial approaches have focused on the HIV envelope protein. At least thirteen different gp120 and gp160 envelope candidates have been evaluated, in the US predominantly through the AIDS Vaccine Evaluation Group. Most research focused on gp120 rather than gp41/gp160, as the latter are generally more difficult to produce and did not initially offer any clear advantage over gp120 forms.
An AIDS vaccine that appears to have worked at least partly in Thailand may only temporarily protect patients, with the effects starting to wane after a year or so, researchers reported on Thursday.