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Beyond Condoms: Chemical and Physical Barriers to Protect Women from HIV
Sharon Hillier
Univ of Pittsburgh Sch of Med, Magee-Womens Hosp, PA, US
Background: HIV
prevention messages for women highlight abstinence, monogamy, and condom usage.
However, many women living in the highest HIV incidence areas are married or
have a single sexual partner. Condom usage is difficult to negotiate within
these relationships, and, during preparedness studies for a clinical trial of microbicides, use of condoms by male partners during
follow-up was 20% and did not increase despite provision of male condoms and
extensive counseling. Female-controlled barriers are being evaluated in ongoing
HIV prevention trials and self-reported data suggest that these methods are
more likely to be used than male-controlled condoms. Female condoms are the
only female-controlled physical barrier method that has empirical data supporting
their potential to provide HIV prevention comparable to male condoms. A
decrease in sexually transmitted infections has been reported with the use of
female condoms. Diaphragms and other cervical barriers are worn internally,
physically protecting the cervix and access to the upper genital tract, the
main sites of entry for HIV and many sexually transmitted infections.
Conclusions: There
is a growing consensus that a highly effective female-controlled method will
require a combination of products or methods, and combining cervical barriers
and microbicides offers a compelling approach to HIV/
sexually transmitted infections prevention. Additional work is focused on
development of microbicides, which are not coitally dependent. Strategies currently under development
include daily application of ART-based gels and intravaginal
rings that can be inserted monthly and which slowly release molecules with high
levels of potency against HIV. Ongoing studies are evaluating daily vs coitally dependent usage of tenofovir gel and non-nucleoside reverse transcriptase
inhibitors, such as TMC-120 in vaginally applied rings. Combinations of
chemical agents, including ART, and fusion or entry inhibitors are also being
developed. Long-term studies will be needed to ensure that microbicide
usage does not lead to condom migration and that the microbicide
products do not weaken the male or female barrier methods. Development of
physical and chemical barrier strategies for women will provide real prevention
strategy for women at risk of HIV.
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