Old cancer drug raises hope by rousing HIV

MELBOURNE, Australia — In a pilot study in Denmark, AIDS researchers seeking to cure HIV with a one-two punch got an early hint the approach may work by successfully using an old cancer drug to kick the virus out of hiding.

Researchers from Aarhus University gave the medicine romidepsin to six HIV-infected people in an effort to rouse the virus from the so-called reservoirs where it sleeps. It worked: Infusions of the drug woke the virus up and caused it to start reproducing, a step that may allow the immune system to clear it, according to results reported Tuesday at an International AIDS Conference in Melbourne.

Antiretroviral pills can keep the virus in check but don’t eliminate it from hidden reservoirs deep in the body. Studies show that when patients stop taking their meds, the virus proliferates from the reservoirs, forcing them to resume treatment. Bionor Pharma, based in Oslo, is studying romidepsin as part of a “kick-and-kill” approach to curing HIV in which romidepsin kicks HIV out of hiding before another drug called Vacc-4x would prompt the immune system to kill it.

“It’s still just another step toward something that may end up being a cure for HIV, so it’s a step in the right direction,” co-author Ole Schmeltz Sogaard, a senior researcher in the department of infectious diseases at Aarhus University Hospital, said in Melbourne.

Romidepsin was used at a third of the normal cancer dosing, he said. Side effects were consistent with those known to occur with romidepsin and others in a class of compounds that interfere with the function of the enzyme histone deacetylase. No severe toxicity was observed and no dose reductions were necessary, Sogaard said in an email.

Bionor announced successful completion of the pilot study in May, and said it would start enrolling patients during the second quarter for the second part of the study, in which HIV- infected people will receive Vacc-4x and three weeks of romidepsin.