HIV vaccine trials labor to enroll women

Scientists running clinical trials of HIV/AIDS vaccines are struggling to determine the effectiveness of their vaccine candidates on women due to a lack of women enrolling in the trials in developing countries.

Only about a fifth of participants in Phase I and II HIV vaccine trials in most sites in Africa are female, SciDev.net reports. But more women than men are infected with HIV. Because women have a higher viral load, their immune response to vaccines could differ from those of men. Some African women attend HIV screenings, but tend to avoid enrolling in trials, Merlin Robb, clinical deputy director of the U.S. Military HIV Research Program, told SciDev.net.

The trials require females to use contraceptives and not become pregnant, a difficulty for some women eligible for the trials who are within reproductive age.

The number of visits to a site during the trial may also prove difficult for some women. Women who participated in the CAPRISA 004 microbicide trial in South Africa needed to visit the site 22 times and undergo 7 internal examinations in a period of 18 months.

- more from SciDev.net

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