emboldened by monkey study results recently said they would
expand tests of the pill Truvada, which combines Gilead
Science's Viread and Emtriva, as a possible preventive
for healthy people at high risk of HIV infection.
Gilead, however, has acted to tamp down excitement about
the development, in part out of fear that Truvada will be
seen as a "biomedical condom." Health officials too
are worried: They say the drugs should be administered
only along with counseling, condoms, and regular HIV
and Emtriva are approved for use by HIV-positive
patients, not as a preventive for HIV-negative people.
Doctors, however, can prescribe them for "off-label"
use; in addition, they are available online. No one
knows how many people are taking the pills for
prevention, but some experts, including Mitchell Warren of
the AIDS Vaccine Advocacy Coalition, suspect their
numbers are growing. Some analysts say this off-label
use could come back to haunt Gilead, particularly if
the pills are eventually found to be ineffective at
The Centers for
Disease Control and Prevention, the National Institutes
of Health, and the Bill and Melinda Gates Foundation are
each funding separate human trials of Viread around
the world to learn whether it could be an effective
prevention pill. Other than providing the Viread,
Gilead is not deeply involved in these studies.
The idea that any
of their drugs can be used to prevent HIV is promising
but preliminary, company officials say, because most of the
available data come from monkey studies. But because
the monkey trial results have been so promising,
officials are now planning to switch one human trial
from Viread to the combination. (AP)