AIDS vaccine update: With Thai trial, broadly neutralizing antibodies, new technologies and monkeys that met the SIV challenge, “we’re closer than ever”

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Do vaccines make a difference? Click on image above to read chart, used by Marovich to illustrate the impact of vaccines on once widespread diseases.

NIH AIDS Vaccine Research Program Director: “The future of HIV-1 Vaccines is bright.”

In 1997, scientists announced the birth of Dolly the cloned sheep, a computer named Deep Blue beat reigning chess champion Gary Kasparov, and the Hubble telescope brought the far reaches of outer space closer.

President Bill Clinton pointed to all of these that year in his May 18 commencement address at Morgan State University* in Baltimore, when he called for the development of a vaccine against AIDS in the next decade. Announcing that the National Institutes of Health would establish a new vaccine research center to make it happen, he added, “it is no longer a question of whether we can develop an AIDS vaccine, it is simply a question of when.”

Ten years passed, during which Dolly the sheep died young, and Kasparov accused the computer of cheating. The end of the ten years was capped by the halt of the the STEP and Phamibili clinical trials of the most promising AIDS vaccine candidates to that point, when it showed no effectiveness in either preventing acquisition of HIV, or ameliorating its impact. Such is the nature of progress. After 20 years in the making, the Hubble telescope which had started its mission with a miscroscopic but catastrophic error that was fixed, continued its mission.

And on Monday, the day after the 17th anniversary of Clinton’s challenge — now known as HIV Vaccine Awareness Day, Mary Marovich, director of NIH’s Division of AIDS Vaccine Research Program reviewed advances over the last five years that have proved a vaccine could work, that have yielded information on how it would work, and that shed light on the challenges. In the world of vaccine research, even the most unexpected disappointments are discussed as if they were successes because the information they yielded redirected research. On this occasion, Marovich was discussing the kind of  successes that propel research.

“The future is bright,” Marovich said. “We’re closer than ever.”

She was presenting the updates for AVAC’s Breakthroughs and Big Questions: AIDS Vaccine Research in 2014 webinar, part of its Research and Reality discussion series.

She began with the Thai RV144 trial, which in 2009 showed at the end of 12 months a nearly 60 percent lower rate of HIV acquisition among participants who were vaccinated than among those given a placebo. Work on that candidate continues to find ways to extend its effectiveness, and to assess its effectiveness in other settings.

She went on to discuss antibodies, the kind with broadly neutralizing effects needed to confront the rapid mutations of HIV. Some people produce these in response to HIV infection, but by then the virus has a head start. Researchers are looking at ways to induce them by vaccination before infection, and where scientists once could identify only a few, they now know of hundreds.

Then there is the story of the monkeys, administered a vaccine propelled by the ancient cytomegalovirus. That vaccine induced an immune cell response that led half of the monkeys to clear the simian equivalent of HIV — the Simian Immunodeficiency Virus.

For all of this, the steps that would necessarily follow any of that could at best put the wide distribution of a vaccine for HIV an optimistic decade away.  And while yes, a decade has been set as a goal before, Marovich noted, realization has edged closer to reality in the time since, bringing a vaccine closer than ever before.

“We’re setting the stage,” as Bill Snow, of the Global HIV Vaccine Enterprise, put it, after Marovich’s presentation. “We need to keep this going forward.”


Marovich presented this graphic, adapted from a 2005 NEJM article illustration

* C-Span video opens at close previous program; President Clinton’s Commencement address begins at :52.

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