A clinical trial of the HIV prevention drug Viread (tenofovir), which took place in Africa, showed promising results, as fewer people taking the once-daily pill became infected with HIV, compared with those who took a placebo. Family Health International conducted the trial with 859 women, many of whom were prostitutes. The women, none of whom had HIV at the beginning of the trial, were divided into 2 groups: 427 women received Viread and 432 received a placebo. All the women in the trial received sexual health counseling and condoms. At 6 months, 2 women in the Viread group became infected with HIV, compared with 6 women in the placebo group. The researchers, while encouraged by these results, warn against drawing broad conclusions from a small study. They also note that providing the women in the placebo group with counseling and condoms resulted in 50% fewer infections than expected. More studies will be conducted in other parts of the world over the next year.

Ms. Farley is a freelance medical writer based in Wakefield, RI.