Sunday, May 06, 2007

Microbicides: Empowering women

Current global AIDS statistics are staggering, to say the least. Approximately 40 million people worldwide are living with the disease, while 14,000 new infections occur each day. Women make up almost 50% of adult infections, but this figure is higher in sub-Saharan Africa, where women are 30% more likely to be HIV-positive than men. Due to physiological differences, women are twice as likely as men to contract HIV from an infected partner, but many lack the necessary tools for protection. Even if the tools are available, poverty and inequality can make it impossible for women to have control over their sexual interactions. The ABCs of prevention (abstain, be faithful, and use condoms) are useless without male cooperation. The ABCs are even more ineffective for married women with non-monogamous husbands because, as Melinda Gates states, “abstinence is unrealistic, being faithful is insufficient, and the use of condoms if not under their control.”
Microbicides are a new and important HIV prevention method that can put the power of protection in the hands of women. Microbicides are formulated as gels, creams, suppositories, or films that can kill or neutralize viruses when applied before sexual intercourse, thus preventing infection. Because women could apply the microbicide without the cooperation or awareness of their partners, they would have more control over preventing an HIV infection. Ideal microbicides would also protect against other STDs that can facilitate HIV transmission and come in spermicidal or non-spermicidal formulations that allow pregnancy while still offering protection. An ideal microbicide should be active upon application, remain active for an extended period of time, and be tasteless, odorless, and invisible in order to prevent detection and interference with sexual activity. Finally, for distribution and accessibility, an ideal microbicide must be cheap and easy to store.
There are three major approaches a microbicide can use to prevent infection. Some microbicides act as physical barriers that prevent HIV from entering tissue. They are liquid at room temperature, but become gel-like inside the body and work like a condom. Others contain molecules that inhibit the virus itself. They might create an acidic environment in which the virus cannot survive, or contain known anti-HIV drugs, such as AZT. Still others prevent infection by interfering with viral surface proteins, therefore preventing attachment. Researchers hope that multiple methods of prevention will be combined into one microbicide to increase effectiveness.
While no microbicides have been approved for general use, twelve versions are currently undergoing various phases of clinical trials. However, there are several important issues that stand between microbicide development and widespread use. Most microbicides are developed by small biotech companies and educational research institutions. Only 1% of federal research funding goes toward microbicide research, and pharmaceutical companies are unwilling to invest because the women who need their products will be unable to pay for them. Once microbicides are developed, they must go through a series of clinical trials. International support to build the necessary infrastructure for trials in developing countries is crucial so testing can occur in the locations where products will be most used. Microbicide producers are concerned about the low efficacy of first-generation microbicides and the potential for increased risk behavior, such as condom substitution. However, most agree that since condom use is rarely consistent, microbicides can provide better protection than nothing at all. Finally, only 20% of the population at high risk of infection currently has access HIV prevention methods. Even a 100% effective product does little good if it cannot be distributed to those who need it most.
While microbicide development is currently facing many challenges, there is no doubt that microbicides are a powerful HIV prevention tool. By giving women more control over HIV protection we can drastically reduce the number of new infections each year and save millions of lives.

I'm Page Bomar. Thanks for lsitening.

No comments: