By Rod McCullom
This month has seen a flurry of activity around new and exciting potential HIV-vaccine concepts.
In Kenya, clinical trials began on two promising new designs for preventive HIV vaccines. In South Africa, researchers launched clinical trials for a therapeutic vaccine intended to strengthen the immune systems of people living with HIV/AIDS. And scientists at the University of Maryland School of Medicine announced their biggest research gift ever: $23.4 million to continue the university’s decades-long work on an HIV/AIDS vaccine from a consortium led by the Bill & Melinda Gates Foundation.
“I don’t think anyone can argue that this has been an exciting time,” says Mitchell Warren, executive director of AVAC, originally the AIDS Vaccine Advocacy Coalition, the 16-year-old New York City-based group that advocates for the development of an AIDS vaccine and biomedical prevention.
Prevention technologies have been in the news lately — from the breakthrough microbicide research at the 2010 International AIDS Conference to the recent data on the potential of pre-exposure prophylaxis, or PrEP, to help protect gay and bisexual men. And all have potentially serious implications for African Americans, who represent only 13 percent of the U.S. population but account for 45 percent of new HIV infections.
Preventive Vaccine Trials
“There are three major areas of work right now around vaccines,” Warren explains. “On the one hand, there is a lot of work focused on doing better than what we did in Thailand, how to modify that vaccine candidate and improve upon it.”
Announced in September 2009, the U.S.-funded “Thai Prime-Boost” (pdf) trial — the world’s largest, with 16,000 volunteers — combined two previously unsuccessful vaccines. But while a medical milestone (the vaccine reduced new infections by almost a third), it was not effective enough.
“The second major area of work is other new vaccine concepts. The trial in Kenya is one example,” says Warren of the research being conducted in collaboration with the International AIDS Vaccine Initiative. The candidate vaccine affects both antibodies and cellular immune response and has been described as “the most advanced AIDS vaccine design” likely to succeed.