Giving periodic injections of a pair of broadly neutralizing HIV antibodies to people living with the virus during an interruption in their standard oral antiretroviral (ARV) treatment was associated with improved CD4 and CD8 T-cell responses in a recent early-stage trial.

A team of researchers at the University of Montreal Hospital Research Center (CRCHUM), the Rockefeller University in New York City and the University of Cologne in Germany conducted a Phase Ib clinical trial of a pair of monoclonal broadly neutralizing antibodies that were manufactured in a lab. They published their findings in Nature Medicine.

The researchers recruited nine people with HIV who had a fully suppressed viral load thanks to ARV treatment. All the participants had HIV that was susceptible to the two antibodies according to initial tests.

Under instruction from the investigators, the participants interrupted their ARV treatment and then received the first of three injections of the pair of antibodies, with subsequent injections three and six weeks later. They received weekly viral load testing during their time off ARVs.

Analyses of the participants’ blood during this period indicated that the antibody treatment was associated with a boost in the activity level of CD4 and CD8 immune cells responding to HIV.

All the participants maintained a fully suppressed viral load during the 15 weeks they spent off ARVs.

“But are these T-cell responses more effective at controlling HIV than before this intervention?” Daniel E. Kaufmann, MD, a CRCHUM researcher and a professor at the University of Montreal, asked in a press release. “This remains to be demonstrated."

“In the future,” said Kaufmann, “this kind of antibody therapy will be studied in larger clinical trials for HIV prevention or treatment, as antibodies are very well tolerated by humans and can efficiently block the virus for many weeks.”

To read a press release about the study, click here.

To read the study abstract, click here.