A group of recently discovered antibodies could be used as therapy for HIV.
"Our data demonstrate, for the first time, profound therapeutic efficacy of broad and potent HIV-specific monoclonal antibodies in rhesus monkeys chronically infected with a highly pathogenic simian-human immunodeficiency virus,[the monkey version of HIV]," study lead author Dan H. Barouch, MD, PhD, Director of the Center for Virology and Vaccine Research at BIDMC, Director of the Vaccine Program at the Ragon Institute of MGH, MIT, and Harvard, and Professor of Medicine at Harvard Medical School, said in a Beth Israel Deaconess Medical Center news release.
Antibodies work differently than the standard HIV treatments.
"Antibodies directly target free virus as well as virally infected cells, whereas existing antiretroviral drugs only inhibit the replicating virus," Barouch said. "Antibodies may, therefore, offer a unique therapeutic strategy that could potentially be combined with antiretroviral drugs."
The research team gave the rhesus monkeys either one of the antibodies, or a mixture of several.
The method proved to be successful; the virus rapidly declines in the monkeys' blood and tissue. In three to seven days the virus levels had dropped so low they could not be detected. The levels were also reduced in the lymph nodes and stomach. The monkeys also had a better immune system response for fighting the virus.
"In most cases, the virus rebounded when antibody titers declined after a median of 56 days, but, remarkably, the subset of animals with the lowest starting levels of virus maintained undetectable viral loads for the duration of the study, in the absence of further antibody infusions, Barouch said.
"These data strongly encourage the development of monoclonal antibodies as a novel therapy for HIV in humans," he notes. "Monoclonal antibodies in conjunction with antiretroviral drugs can be explored for treatment intensification, pre- and post-exposure prophylaxis, and virus eradication strategies for HIV in humans," he said.
