Push is on for increased microbicide R&D funds
Products are in phase III trials
At least 12 million American women are waiting for them. More than 600 scientists from around the globe just met to discuss the latest research about them. Yet despite this interest, there still are no microbicides on the U.S. market with proven effectiveness against infection by HIV and sexually transmitted disease (STD) pathogens.
However, recently introduced legislation in Congress may help increase the federal investment in microbicide research. Rep. Connie Morella (R-MD) has introduced H.R. 3891, the Microbicides Development Act of 2000, which calls for enlarging the $25 million now earmarked for microbicide development to $50 million in fiscal year 2001 and $75 million in fiscal year 2002.
To protect themselves from the risk of HIV/ AIDS and other STDs, women now can use a female condom or negotiate male condom use with their partners. While nonoxynol-9 (N-9), now used as a spermicide in pregnancy prevention, does offer some protection against bacterial STDs such as gonorrhea, chlamydia, and trichomoniasis, its ability to prevent the transmission of viral STDs, particularly HIV, is under question. (Contraceptive Technology Update offered an update on N-9 research in its April 1999 issue, p. 40.)
Vaginal microbicides offer a self-controlled method of protection that does not require partner knowledge or cooperation. Mechanisms of action include:
• blocking infection by creating a barrier between the pathogen and the vagina;
• killing or immobilizing pathogens;
• preventing a virus from replicating once it has infected the cells that line the vaginal wall.1
In addition to increased funding, the proposed legislation also calls for creating a program under the auspices of the National Institutes of Health (NIH) in Bethesda, MD, to coordinate microbicide research efforts now taking place in governmental agencies such as the NIH and the Atlanta-based Centers for Disease Control and Prevention (CDC), says Heather Boonstra, MA, senior public policy associate with the Alan Guttmacher Institute. The legislation also asks those agencies to develop a five-year implementation plan regarding microbicide research and development, she notes.
"What we are looking at is the fact that there are about 60 products now that are in the developmental pipeline that aren’t moving as quickly as we would like," explains Boonstra. "This is trying to streamline some of that process."
In 1996, Secretary of Health and Human Services Donna Shalala announced that the federal government would invest $100 million ($25 million per year) in microbicide development over four years.1 An accounting of funds spent the following year showed that 73% was earmarked for microbicide product development and testing, while the rest was allocated for basic research with multiple purposes that may have some application to microbicides.
For example, if a question on the National Survey of Family Growth addressed spermicide use, it was attributed to microbicide research, says Boonstra. By calling for funds to be earmarked for product research and development, advocates hope dollars will translate into progress in delivering a safe, effective product.
When such a product does arrive, it will be greeted with much interest. A nationally representative survey of U.S. women ages 18 to 44 shows that 94% would be interested in using a microbicide if they ever found themselves at risk for STD infection.1
The first international conference on microbicides just ended its inaugural three-day session with outstanding results, says Polly Harrison, PhD, director of the Alliance for Microbicide Development in Takoma Park, MD. Conference sponsors included the Alliance; American Foundation for AIDS Research in New York City; the CDC; Center for Health and Gender Equity in Takoma Park, MD; Contraceptive Research and Development Program in Arlington, VA; Family Health International in Research Triangle Park, NC; International AIDS Society in Stockholm, Sweden; Joint United Nations Programme on HIV/AIDS (UNAIDS) in Geneva, Switzerland; the NIH; Office of AIDS Research in Bethesda, MD; Population Council in New York City; and the United States Agency for International Development in Washington, DC.
More than 600 attended, with about 43% coming from outside the United States, Harrison says. Information was shared regarding products in development, basic science issues, clinical questions, and behavioral and public health issues. Proceedings of the conference are to be published this summer in the journal AIDS (International AIDS Society, Stockholm, Sweden), says Judith Auerbach, PhD, behavioral and social science coordinator in the Office of AIDS Research.
Products in phase III
Just two microbicide products, Conceptrol Gel (manufactured by Ortho-McNeil Pharmaceuticals of Raritan, NJ) and Advantage-S (manufactured by Columbia Laboratories of Aventura, FL) are in phase III trials, reports Ronald Roddy, MPH, senior epidemiologist at Family Health International. Both of these products are commercially available in the U.S. market as spermicides.
Roddy’s study on microbicidal use of Conceptrol and the UNAIDS investigation of similar use for Advantage-S will not be finished until later this year, says Roddy. A separate study of Conceptrol sponsored by the NIH and HIV Network for Prevention Trials (HIVNET) is just starting and will run for about three years, Roddy notes. HIVNET is a multicenter, collaborative research network founded by the Division of AIDS in the National Institute of Allergy and Infectious Diseases in Bethesda, MD.
1. Wulf D, Frost J, Darroch JE. Microbicides: A New Defense Against Sexually Transmitted Diseases. New York City: Alan Guttmacher Institute; 1999.