The FDA should approve the first HIV test for at-home use and
over-the-counter sale, the agency’s advisory committee said today in a
unanimous 17-0 vote. The test is OraQuick from OraSure. It’s a home
version of a rapid HIV test already being used by health care
professionals in community settings. The committee’s opinion was summed
up by panel member Steven W. Pipe, MD, of the University of Michigan.
“I can’t get past the quarter of a million people in the U.S. who
have HIV and are not tested,” Pipe said at the meeting. “If we make any
dent in that, the answer is yes, we realize the [OraQuick At-Home]
benefit outweighs its risks.” The price tag of the at-home test has not
yet been set but will be a good bit more than the $20 cost of the
professional version. That’s partly because it will come with a detailed
instruction booklet, and because OraSure will set up a call center with
trained counselors available 24 hours a day, seven days a week. “The
price will be substantially lower than $60,” Stephen R. Lee, PhD,
OraSure executive vice president and chief science officer, told the
committee.
Now anybody concerned about whether they have the AIDS virus and who
can afford OraQuick may be able to take the test at home. But there’s a
catch. In clinical trials enrolling regular people at risk of HIV
infection, some 7% of people with HIV infection are wrongly told they
don’t have HIV. With a professional test, that happens only 2% of the
time.
According to FDA calculations, this means that in the first year
after approval, the test will wrongly tell about 3,800 people with HIV
infection that they are not infected.
The FDA calculates that in the first year after OraQuick is approved
for home use, an extra 45,000 people will correctly learn they have HIV.
That’s a big deal. The CDC estimates that there are 50,000 new HIV
infections every year. About 1.2 million Americans are HIV-infected,
and about 1 out of 5 don’t know they carry the AIDS virus. Such
people may be more likely to spread the virus than those who know they
are infected.
Panel member Susan Buchbinder, MD, director of HIV research at San
Francisco’s health department and a long-time AIDS researcher, noted
that while some people may get inaccurate results, the test likely will
alter people’s HIV risk behavior.
“A positive HIV test does reduce risk behavior. A negative test
doesn’t have much of an influence,” Buchbinder said. “We must assume
there will be some incorrect results. The question is how do we help
people understand a negative result might not truly mean a person is
negative for HIV.”
There’s another catch to the OraQuick in-home test: the “window
period.” The test detects anti-HIV antibodies, but these antibodies
appear many weeks after infection.
A recent study suggests that rapid HIV tests such as OraQuick will be
accurate two months after infection. OraSure says that to be safe,
people should assume the OraQuick test will miss any new HIV infection
contracted in the past three months. This means that people with any HIV
risk behavior such as unprotected sex or needle sharing will need
regular retesting, as is true with any HIV test. And confirmatory
testing at a doctor’s office or free clinic is strongly advised for
those who test positive but also for those who test negative despite
high-risk behavior.

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