Vaginal Ring With Drug Lowers H.I.V. Rates in African Women
A flexible and inexpensive ring that is inserted into the vagina, where it slowly releases an antiviral drug, helped protect African women against contracting H.I.V. from their sexual partners, researchers said Monday in reports on two major studies that included more than 4,500 women.
The protection was not complete: Overall infection rates were reduced by only 27 percent and 31 percent, though women who were over 21 fared better. But researchers said that the device was still a major advance and that the results were the most promising to date in H.I.V. prevention for African women. They said they would press ahead to get the ring approved and widely distributed as quickly as possible.
“The hope was to find something that could be usable enough by women that it would provide H.I.V. protection, and that’s what we got,” said Dr. Jared M. Baeten, from the University of Washington, who led one of the studies, called Aspire. “It gives me tremendous optimism.”
Globally, almost 37 million people are infected with H.I.V., more than half of them women. The majority of those women live in sub-Saharan Africa, which has some of the highest H.I.V. rates in the world. Three earlier H.I.V. prevention studies in African women failed, largely because participants did not consistently use the methods offered, which included antiviral pills and microbicidal vaginal gels.
The two studies released on Monday, in H.I.V.-negative women ages 18 to 45, were presented in Boston at the annual Conference on Retroviruses and Opportunistic Infections. Women over 21 who used the ring most consistently fared better.
Dr. Baeten said the two trials, similar in design, but independent of one another, were done in parallel because regulators usually require data from two studies to approve a new product.
“In science, replication is incredibly important,” Dr. Baeten said. “You have to show something and show it again to know it’s real. This is the first time we have replication for this kind of prevention tool in women.”
The ring, 2.5 inches across and made of silicone, is left in the vagina for a month and then replaced. It costs $5, does not need to be refrigerated and has a shelf life of five years. It releases the drug dapivirine. Part of its appeal and its effectiveness is that women do not have to ask for their partners’ permission or cooperation to use it. A man may refuse to wear a condom, or deny a woman’s wish to take pills or use vaginal microbicides before sex. But a woman can insert the ring herself, and once it is in place neither she nor her partner can feel it. She does not even have to tell him about it.
“I remember really vividly talking with some of the participants in Zimbabwe partway through the study, and they would say, ‘This ring is mine,’” Dr. Baeten said. “There was ownership of the ring because she could control it.”
Study participants used the phrase “set it and forget it” to describe the ring, he added.
The Aspire study, led by the Microbicide Trials Network, which is financed by the National Institutes of Health, enrolled 2,629 women at 15 sites in Malawi, South Africa, Uganda and Zimbabwe. Half received dapivirine rings, and half received placebo rings that contained no medication. The results were published on Monday in The New England Journal of Medicine.
The second project, called t he Ring Study, led by the nonprofit International Partnership for Microbicides, included 1,959 women at seven sites in South Africa and Uganda. The results have been submitted to a medical journal, but have yet to be published.
In the Aspire study, over all there were 27 percent fewer cases of H.I.V. in women who received drug-treated rings, compared with those given placebo rings. The actual numbers of infections were 97 in the placebo group and 71 in the treated group.
But when the women were sorted by age, researchers found that the device was considerably more effective in those over 25: Their infection rate was cut by 61 percent. In those over 21, the reduction was 56 percent.
In the Ring Study, the infection rate was reduced by 31 percent over all and 37 percent in women over 21.
The ring offered little or no protection to women under 21 in either study.
Researchers think the results were better in the older women because they used the devices more consistently. But the scientists also say more research is needed to find out whether there is some biological factor making younger women more susceptible to H.I.V. infection and harder to protect.
An advocacy group for H.I.V. prevention, AVAC, issued a statement praising the studies, but said more work was needed before the ring is made widely available, because of uneven use and the relatively low figures on effectiveness. In the meantime, the group said preventive pills should be made more widely available to women in Africa.
“Clearly, we would have liked to have seen a higher efficacy over all,” said Zeda Rosenberg, the founding chief executive officer of the International Partnership for Microbicides, which developed the ring. “We would have liked to have seen more women in the trial be able to use it consistently.”
The studies revealed that the ring was not “forgiving,” Dr. Rosenberg said: It has to be used full time, or it does not work.
Tests done during the study, measuring dapivirine levels in the women’s blood and in the rings that were returned after they were supposed to have been used for a month, revealed that some of the women must have removed the rings for significant periods of time.
About 25 percent of the women apparently used the ring “highly consistently,” Dr. Rosenberg said, adding that the figure was consistent with other studies in sub-Saharan Africa involving pills and gels offered for H.I.V. prevention. With pills and gels, that low level of use translated into no protection. But with the ring, the same amount of use resulted in a 30 percent reduction in infection, which was “comforting,” she said.
She said her group would submit applications for approval of the ring early next year to regulators in South Africa and Europe. Future versions will last three months, she said, and some will combine antiviral medication with birth-control drugs.
An earlier version of a picture caption with a photograph of people in a South African town misidentified the woman speaking. She is a community liaison officer, she is not Holly Seltzer.