AIDS Vaccine Blueprint launched: A challenge to the field

The AIDS Vaccine Blueprint 2008, IAVI’s biennial report on the state of AIDS vaccine research and development and a roadmap for the field, was released at the XVII International AIDS Conference in Mexico City, August 3-8. It issues several challenges to AIDS vaccine researchers and outlines interim goals toward overcoming many of the obstacles impeding vaccine development, as well as milestones by which the field can measure its progress.
The Blueprint, which IAVI has been producing since 1998, strikes a different theme and tone than two years ago when more than two dozen AIDS vaccine candidates were moving through the pipeline, including Merck’s cellular immunity-based vaccine, known as MRKAd5, which many researchers regarded as the most promising.

Merck and the US National Institute of Allergy and Infectious Diseases stopped immunizations in the Phase IIb test-of-concept trial of this candidate last September after it failed to provide any protection against HIV infection. “Two years ago, we all thought we had a signal of hope from Merck,” said Seth Berkley, the founder and CEO of IAVI. “What has happened is we’ve learned a lot about the science.”

Because most of the AIDS vaccine candidates currently in clinical trials employ strategies similar to MRKAd5, the IAVIBlueprint urges stakeholders to “review their portfolios and drop candidates considered to have a low probability of success.”

IAVI suggests that the resources be spent instead on research efforts to develop a more diverse clinical pipeline of AIDS vaccine candidates that can induce both cellular immune responses and antibodies against HIV (see VAX July 2008 Special Issue on Understanding the Immune System and AIDS Vaccine Strategies).

Other recommendations in the Blueprint include establishing incentives to enhance innovation in AIDS vaccine discovery, and training the next generation of researchers. “Science is not a straight line,” said Alan Bernstein, president of the Global HIV Vaccine Enterprise, commenting about the recent setbacks in the AIDS vaccine field. “It’s clear after 25 years that we are on a long journey.” —Regina McEnery