Antibodies Showing Promise Against HIV

Updated Oct. 30, 2013 3:53 p.m. ETResearchers have identified a potentially powerful new treatment for HIV infection that would use recently discovered antibodies to disable the virus, a finding that promises to energize research in both prevention and treatment.
Two studies published Wednesday online in the journal Nature found that administering a round of potent human antibodies to monkeys infected with a hybrid version of HIV caused the amount of virus in their bodies to drop to low or undetectable levels that were sustained for weeks.

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The virus dropped to undetectable levels within three to seven days after an intravenous infusion of a single antibody in one of the studies, conducted by a research team at Beth Israel Deaconess Medical Center in Boston. The antibody infusions boosted the monkeys’ ability to fight off the virus, and after the treatment, the virus didn’t rebound at all in those monkeys that had the lowest levels of virus at the outset of the study.
The surprising results, which would need to be tested on humans, suggest a possible new treatment for HIV that could target infected cells as well as virus that is spreading. Antiretroviral drugs—the current HIV treatment—control the disease by preventing the virus from spreading, but don’t directly kill off infected cells.
“The effect we saw was very profound,” said Dan Barouch, professor of medicine at Harvard Medical School and researcher at Beth Israel Deaconess Medical Center, and lead author of the larger study. “It was such an unexpected result, we actually decided we couldn’t tell anyone until we did it again.”

Harvard Medical School’s Dan Barouch, lead author of the larger study. M. Scott Brauer for The Wall Street Journal

The second, smaller study was led by researchers at the National Institute of Allergy and Infectious Diseases, part of the National Institutes of Health.
While antibodies are commonly used in treatment of cancer and some other conditions, they hadn’t been considered promising for HIV after disappointing experiments about a decade ago.
But advances in molecular techniques have helped scientists more recently pinpoint unusually powerful antibodies that have the ability to neutralize the vast majority of HIV strains. Those findings have helped re-energize the pursuit for a vaccine, and now the enthusiasm could spread to treatment research as well, said Francis Collins, NIH director.
“Could we shift over treatment of HIV from taking antiretroviral tablets every day to [having] an injection of monoclonal antibodies every three months?” he asked. “This is a really new wrinkle in a field that needs new wrinkles.”
The findings “could revolutionize efforts to cure HIV,” researchers Louis Picker and Steven Deeks wrote in an accompanying commentary. Adding antibody therapy to an antiretroviral drug regimen could accelerate the destruction of infected cells that can produce more virus but aren’t killed off by conventional HIV treatment, they wrote. While Dr. Barouch’s study showed evidence of a declining number of infected cells, the process still needs to be definitively proven, according to Dr. Picker, associate director of the Vaccine and Gene Therapy Institute at Oregon Health & Science University.
“The key will be now to show this holds true in human beings,” said Salim Abdool Karim, director of the Center for the AIDS Programme of Research in South Africa, who wasn’t involved in the research but called it “an incredible finding.” The results should turbocharge further research on the use of antibodies both for therapy and vaccination, he said.
Implementing this type of therapy would be expensive and logistically impractical, he said, while antiretroviral drugs are inexpensive.
“But that’s not what this is about,” he said. “This is about proof of concept, showing you can have an impact on the virus. Once you do that, the obvious thing is to get the body to make these antibodies itself.”
Said the NIH’s Dr. Collins: “If we could convince the immune system to develop these antibodies routinely, then we’d really have something.”
Write to Betsy McKay at betsy.mckay@wsj.com and Ron Winslow at ron.winslow@wsj.com

Original post: Antibodies Showing Promise Against HIV