Disease Control and Prevention researchers this week at the
12th Conference on Retroviruses and Opportunistic Infections
in Denver reported that injections of two drugs used
to treat HIV patients completely protected monkeys
from becoming infected.
monkeys were injected with a version of Truvada, Gilead
Science's once-daily pill that includes its drugs Viread and
Emtriva. The monkeys were then exposed rectally to
combined monkey-human HIV. The exposures and the
injections continued daily for 14 days. "Treatment
continued for four weeks after last challenge," says Walid
Heneine of CDC.
The six monkeys
that received the drug injections were all completely
protected from infection. Nine monkeys used in a previous
experiment eventually all became infected.
In a statement,
the CDC says, "Study authors believe the findings may
be the strongest animal data yet suggesting that potent
antiretrovirals given before HIV exposure may prevent
sexual HIV transmission." However, they caution that
the drug dose differed slightly from that found in
people taking Truvada. Studies that could determine whether
the findings will translate to humans are ongoing.