VRC DNA/rAd5 HIV vaccine regimen: Phase IIb discontinued

NIH's National Institute of Allergy and Infectious Diseases (NIAID) discontinued the double-blind, placebo-controlled, U.S. Phase IIb HVTN 505 trial after an interim analysis by an independent DSMB showed that the VRC DNA/rAd5 HIV vaccine regimen did not prevent HIV infection nor reduce viral load in vaccine recipients who became infected with HIV. Specifically, in subjects who were in the trial for a minimum of 28 weeks, there were 27 cases of HIV infection in the vaccine arm vs. 21 cases for placebo. In subjects who became infected with HIV during the first 28 weeks of the study, there were 14 cases of HIV infection in the vaccine arm vs. 9 cases for placebo. Through 24 months, there were 41 cases of HIV infection in the vaccine arm vs. 30 cases for placebo.

Additionally, in 30 evaluable subjects who acquired HIV infection at least 28 weeks after entering the study and who were followed for at least 20 weeks after diagnosis, the VRC DNA/rAd5 HIV vaccine regimen did not reduce viral load compared to placebo. The trial enrolled 2,504 HIV-uninfected circumcised men who have sex with men and transgender people who have sex with men. All subjects received HIV risk-reduction counseling and condoms. ...