DEPARTMENT
OF HEALTH & HUMAN SERVICES
Public Health Services
Centers for Disease Control
and Prevention (CDC)
Atlanta, Ga30333
August 4 2000
Dear Colleague:
At
the International AIDS Conference held in Durban, South
Africa, from July 9.14, 2000, researchers with the Joint
United Nations Program on AIDS (UNAIDS) presented
results of an important study about HIV prevention in
woman. They studied a product widely used in spermicides,
nonoxynol-9 (N- 9), to determine if it would be
Effective in preventing HIV transmission. Products
designed to provide a chemical barrier to HIV and STD
transmission are called microbicides. This notice
summarizes the study results and some implications for
use of this product in prevention programs.
From 1996 until May 2000, UNAIDS sponsored a study of
the effectiveness of a gel which contained 52.5
milligrams of N-9 (called COL'1492 in the trial and
Advantag-S in the United States), compared to an
inactive placebo gel. The study was conducted in several
locations in Africa. Nearly 1,000 HIV-negative
commercial sex workers were enrolled in the trial, and
all women were counseled to use condoms consistently and
correctly. In addition to condom use, the women were
asked to use a vaginal gel each time they had
intercourse. Half of the women were provided a placebo
gel and half of the women received an N-9 spermicide
gel. None of the woman, or the researchers, knew which
product each woman received, and all of the women were
informed of the possible risks, benefits, arid unknowns
involved in the spermicide study.
At the end of the trial, researchers found that the
women who used the spermicide N-9 gel had become
infected with HIV at about a 50% higher rate than women
who used the placebo gel. Further, the more frequently
women used only N-9 spermicide gel (without a condom) to
protect themselves, the higher their risk of becoming
infected. Simply stated, the spermicide N-9 did not
protect against HIV infection and may have caused more
transmission. Women who used the spermicide N-9 also had
more vaginal lesions, which might have facilitated HIV
transmission.
This study was conducted among women at very high risk
commercial sex workers who used a great deal of the
product on a frequent basis. The adverse effects might
not be seen at the same level among women who are using
spermicides with N.9 less frequently or in different
formulations. However, given that the spermicide
Nonoxynol-9 has now been proven ineffective against HIV
transmission, the possibility of risk, with no benefit, indicates
that Nonoxynol-9 should not be recommended as an
effective means of HIV prevention.
With the release of these data, the scientific evidence
on spermicide Nonoxynol-9 as an HIV prevention strategy
is now conclusive and significant. As a result
prevention guidelines must be re-evaluated UNAIDS and
CDC will be holding consultations over the next few
months to consider official revisions to public health
guidelines for the use of N-9 for HIV prevention and for
pregnancy prevention in populations at high risk for
HIV. In the interim, those findings have several
immediate implications.
First, any community delivering hierarchical prevention
messages that counsel individuals who can't use a condom
to consider spermicides with N-9 for HIV prevention
should immediately revise these messages. This study
suggests that the use of spermicide N-9 for HIV
prevention may he harmful. Second, anyone currently
using N- 9 as a microbicide to protect themselves from
HIV transmission during anal intercourse should be
informed of the ineffectiveness of this agent and warned
of the potential risk of this practice.
CDC
has never recommended the spermicide N-9 alone for HIV
prevention, but current recommendations do emphasize the
consistent and correct use of condoms, with or without a
spermicide. While the level of N-9 used as a lubricant
in condoms is much lower than the level found to be
harmful in this study, CDC will re-evaluate this
guidance as part of the upcoming consultation. In the
interim, while N-9 spermicide will not offer any
additional protection against HIV, a condom lubricated
with Nonoxynol - 9 is clearly better than using no
condom at all. The protection provided by the condom
against HIV far outweighs the potential risk of N-9. If
given the choice, condoms without N-9 spermicide may be
a better option for HIV prevention.
From a research perspective, these findings point to the
need for accelerated efforts to identify a safe and
effective microbicide. Of the more than 7,000 new HIV
infections occurring in the world each day, about 90%
are the result of heterosexual transmission. In
addition, more than 330 million new cases of other STDs,
such as gonorrhea, chlamydia, and syphilis, occur each
year.
For those who are unable to access condoms or to
negotiate their use, there is an urgent need to identify
an effective alternative to prevent HIV and STD
transmission. Moving forward with the evaluation of
microbicide candidates, which are not likely to cause
the same negative effect seen with Nonoxynol 9
spermicide, should be a public health priority.
We appreciate any assistance you can provide in
disseminating this critical public health information
and will keep you informed as the consultations are
completed
Sincerely,
Helene D. Gayle, M.D., M.P.H.
Director, National Center for HIV, STD, and TB
Prevention
Centers for Disease Control and Prevention
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