Q: What are microbicides?
Dr. Donnica: Microbicides are agents that inhibit
the transmission of certain viruses. The microbicides of greatest interest now
are vaginal agents to inhibit the sexual transmission of HIV, the virus that
leads to AIDS. These agents are desperately needed in underdeveloped nations
where rates of HIV infection among women are rapidly increasing, a high percentage
of intercourse is non-consensual, and condom use is not controlled by women
or the "just say no" philosophy.
Nearly 60 microbicides are in development, with various mechanisms of action,
but only 7 are in the final stages of clinical research. Some are contraceptive,
and some are not. The challenge is to develop agents that can be self-administered
vaginally and suppress HIV, yet which do not affect the vaginal mucosa. This
was a problem with the agent nonoxynol-9; in women at high risk for HIV infection,
it was shown to cause vaginal ulcers, which actually increased HIV transmission.
Created: 4/3/2001  - Donnica Moore, M.D.