A "microbicide" is any substance that can substantially reduce transmission of sexually transmitted infections (STIs) when applied either in the vagina or rectum. Much like today's spermicides, a microbicide could be produced in many forms, including; gels, creams, suppositories, films, or in the form of a sponge or a vaginal ring that slowly releases the active ingredient over time.
No microbicides are currently available, but scientists are studying
over 60 different products and 5 products are in Phase 3 clinical trials
(BufferGel, Carraguard, cellulose sulfate, Pro2000/5, and Savvy). With
sufficient investment and commitment, an effective topical microbicide
may be on the market within 5–7 years. For more information about microbicide
development, including products currently being tested, please visit
the Alliance for
Previously, researchers thought that the spermicide Nonoxynol-9 (N-9) might have offered some protection against STIs. Recent evidence shows that this is not the case. In fact, when used rectally, N-9 may increase the risk of HIV transmission. For more information, see our fact sheet on N-9 [PDF, 33KB].
The need for female-controlled prevention methods
Microbicides would fill an important gap in methods of protection currently
available. Today's prevention options — abstinence, mutual monogamy,
or condom use — are not feasible for millions of women around the
world. Microbicides would not require a partner's cooperation — putting
the power to protect into women's hand.
- Anatomical differences place women at a greater risk of contracting STIs than men.
- Age-related changes in the cervix make risk of infection even higher for adolescent women.
- Many women lack the power within relationships to negotiate condom use and the social and economic resources to abandon these risky relationships.
- Heterosexual sex, once the source of only a small fraction of HIV infections, now accounts for three out of four new infections in women.
Acceptability and future use
- According to current research, more than 6 million women ages 15 – 44 in the U.S. alone are very interested in using a microbicide to prevent an STI.
- Microbicides are less intrusive than condoms and could be applied in advance of intercourse.
- Microbicides could be used without the partner's knowledge.
- Even if microbicides were theoretically less efficacious than condoms, they may be more effective in prevention of STIs due to greater acceptance and usage. In other words, microbicides could have a greater overall protective effect in practice than condoms because they might be used more often and more consistently. In fact, researchers developed a mathematical model that shows that if even a small proportion of women in developing countries used a 60% efficacious microbicide in half the sexual encounters where condoms are not used, 2.5 million HIV infections could be averted over 3 years.
The development of microbicides is very much woman-driven and woman-focused. Large, financially-motivated pharmaceutical companies do not currently see microbicides as a profitable investment. Therefore, the quest for microbicides will only be achieved though the work of many concerned people. It is important for any organizations, advocates, and activists concerned about women’s health to take part in this campaign. To learn more about how you can help microbicides become a reality, please visit the Global Campaign for Microbicides.
Frost, J and Darroch, J, Women’s Interest in Vaginal Microbicides, Family Planning Perspectives, Vol 31, No. 1, (Jan – Feb 1999).