WASHINGTON:
US health advisors on Thursday urged
regulators to approve Truvada, made by Gilead Sciences, as the first preventive
pill against HIV/AIDS instead of just as a treatment for infected people.
The
Food and Drug Administration is not bound by the recommendations of its expert
panel, but it usually follows the experts' advice. A final decision by the FDA
is expected in mid-June.
The
vote came after a marathon 11-hour panel meeting in which about three dozen
health care providers voiced concerns about how the pill could boost risky
behaviors and may lead to a drug resistant strain of HIV.
But
others hailed the panel's recommendation for providing another prevention tool
against human immunodeficiency virus.
"This
brings us closer to a watershed for global HIV prevention efforts," said
Mitchell Warren, executive director of AVAC (AIDS Vaccine Advocacy Coalition),
after the vote.
Warren
said pre-exposure prophylaxis (PrEP), or the method of taking a drug ahead of
potential exposure to HIV, "while not a panacea, will be an essential
additional part to the world's success in ending AIDS.
"For
the millions of men and women who remain at risk for HIV worldwide, each new
HIV prevention option offers additional hope."
Landmark
study results published in 2010 showed that Truvada, made by California-based
Gilead Sciences, helped ward off HIV in healthy gay men who engage in risky sex
behaviors by 44 to nearly 73 per cent.
The
drug is currently available as a treatment for people with HIV in combination
with other anti-retroviral drugs and received FDA approval in 2004.
The
panel's nod came in response to the pharmaceutical company's request for a
supplemental new drug application to market it for prevention purposes.
The
Antiviral Drugs Advisory Committee voted for the drug as a preventive measure
for three groups: 19-3 in favour for men who have sex with men, 19-2 with one
abstention for couples in which a partner is HIV positive, and 12-8 with two
abstentions for other at-risk groups.
Gay men
account for more than half of the 56,000 new cases yearly of HIV in the United
States, according to the Centers for Disease Control and Prevention.
But
critics noted that the pill is costly -- up to US$14,000 per year -- and could
offer a false sense of protection, leading to a spike in unsafe sex and a new
surge in AIDS cases.
"We
need to slow down. I care too much about my community not to speak my
concerns," said Joey Terrill, advocacy manager at the AIDS Healthcare
Foundation, which campaigned against the drug's approval for PrEP.
There
also remains some controversy about which populations would benefit, as trials
in women have shown feeble results, possibly due to poor adherence to the
regimen.
"I
am concerned about the potential for development of resistance," said
Roxanne Cox-Iyamu, a doctor who spoke at the panel's meeting.
"I
am concerned as a black woman that we don't have enough data that this actually
works in women."
According
to nurse Karen Haughey, "human nature I believe is the reason why I
believe Truvada will not work. It is not in our nature to always do as human
beings what we are told 100 per cent of the time."
She
also said a major deterrent is Truvada's main side effects: diarrhea and risk
of kidney failure.
"How
do you justify that when you don't have HIV, when you aren't sick, when what
you are taking will damage your kidneys and give you diarrhea every day?"
The
main set of data considered came from the iPrEx HIV Prevention Study, carried
out from July 2007 to December 2009 in six countries -- Brazil, Ecuador, Peru,
South Africa, Thailand and the United States.
The
study was conducted among 2,499 men who were sexually active with other men but
were not infected with the virus that causes AIDS.
Participants
were selected at random to take a daily dose of Truvada -- a combination of 200
milligrams of emtricitabine and 300 milligrams of tenofovir disoproxil fumarate
-- or a placebo.
Those
in the study who took the drug regularly had almost 73 per cent fewer
infections. Across the entire study, including those who had not been as
faithful in taking Truvada, there were 44 per cent fewer infections than in
those who took a placebo.
After
the study's publication in the New England Journal of Medicine, some experts
hailed the results as game-changing and the first demonstration that an
already-approved oral drug could decrease the likelihood of HIV infections.
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AFP/fa/wm
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