Vaginal Ring With HIV-Preventing Microbicide Being Tested in African Women
The most powerful prevention against HIV infection would be the development of a vaccine to prevent the spread of the virus, however, those currently under development are likely still at least a decade away. Clinical testing on a long-acting vaginal ring that contains an HIV-preventing microbicide has begun in South African women and will eventually recruit women from three nearby countries.
Microbicide is a general term used for substances that kill viruses or bacteria on contact. A silicone ring, similar to the one used in contraceptive devices such as NuvaRing, developed by the International Partnership for Microbicides, will be impregnated with dapivirine, an antiretroviral medication. The drug is released into the vagina over the course of a month, after which it is replaced.
This is the 15th study undertaken by the IPM, a non-profit group in Silver Spring. Unfortunately, none of the compounds tested to date has worked. Dapivirine has been used to prevent HIV transmission between mother and child with good results. The current study is recruiting 280 women and will evaluate the ring’s safety through blood tests, pelvic exams and interviews.
"This is the one that is most likely to work," said Dr. Zeda Rosenberg, CEO of IPM, at last week’s Women Deliver 2010, an international conference on maternal and child health held in Washington. “Vaginal rings…could be well-suited to deliver HIV prevention drugs for women in developing countries,” she said.
Whether the ring will successfully prevent HIV infection or not will require a larger, third phase of testing that is not expected to begin until next year. The plans for the study include 8000 women from seven countries. Results from that study aren’t expected until 2015.
Other therapies targeted for at-risk women are also being tested. A study of a vaginal gel that contains the antiretroviral tenofovir is underway in South Africa with results expected next month. The US Agency for International Development is also supporting the development of another type of vaginal ring that contains both contraceptives and antiretroviral drugs.
Heterosexual intercourse is the main mode of HIV transmission in the world, with women at somewhat greater risk than men. Every day, 3000 women globally become infected with HIV. Of the 33 million people living with AIDS worldwide, 16 million are women age 15 and older.
Due to rampant gender inequality, women in Africa are especially at risk for HIV infection. Two-thirds of HIV-infected people live in sub-Saharan Africa, and 60 percent of them there are women.
"Women and girls must be given the tools to protect themselves from HIV infection," said Jill Sheffield, President of Women Deliver. "The contraceptive ring has been a formidable tool for women seeking more control over their reproductive health, and it is wonderful to see HIV researchers adapt this technology to tackle the single biggest killer of young women. The simple fact is that we will never be able to fully ensure the health of women and girls globally without halting the spread of HIV and AIDS."