Vaginal Ring Protects from HIV: Study

Durban 2016

By Sumitra Deb Roy

July 20, 2016

Also published by The Times of India

A vaginal ring infused with an antiretroviral drug can reduce HIV risk by a third when used consistently, a study has found out. The findings, drawn from a phase III clinical trial involving 2359 African women, has particularly brought hope for the vulnerable women and girls, who often may not be in a position to refuse unprotected sex.

The findings of ASPIRE - a Study to Prevent Infection with a Ring for Extended Use - presented at the International Aids Conference in Durban, showed that the risk of contracting HIV declined by as much as 75 percent in women who used it without fail for nearly a month. Among other users too, the risk of HIV was cut by nearly 50 percent. It was found to be more efficacious in older women who used it more regularly for a month.

The vaginal ring made of silicone delivers about 4 mg of the antiretroviral drug dapivirine over 28 days following which a new ring has to be inserted. The drug hinders the ability of the virus to replicate inside healthy cells. Initial findings of the study that were released in the beginning of the year found the risk reduction was only 27 percent but subsequent analyses showed that it was far more effective.

"Adherence to HIV prevention strategies is not always perfect and we knew that not all women used the ring consistently, so we developed an analysis to explore the degree of HIV protection that was associated with more consistent use," said Elizabeth Brown, the principle investigator of Microbicide Trials Network (MTN). "Across all analyses, we found that high adherence was significantly associated with better protection," she added. MTN is an HIV/AIDS clinical trials network funded by several international organizations and the community.

Women in the age-group of 18-45 years from Malawi, Uganda, South Africa and Zimbabwe had participated in the study that was carried out between August 2012 and June 2015. The participants were randomly divided into two groups - one who were given the dapivirine ring, and the other who were given a ring that didn't contain any active drug.

Researchers also identified four levels of adherence from zero-use to cent percent and found that in certain cases the HIV protection rate was around 92 percent. The ASPIRE study will now be followed on by another one called HOPE - HIV Open-Label Prevention Extension, where some of the previous participants will be there. HOPE will look into areas about why the ring, despite all the promises, may not be a suitable HIV prevention tool for everyone. It was particularly found to be not so effective in girls below the age of 21 mainly due to adherence. A study with 300 girls and younger women is likely to begin in 2017 in Kenya, South Africa and Zimbabwe to understand why the ring didn't work in young women.

Simultaneous studies are also going on to understand how the presence of certain bacteria in a woman's body could make her more susceptible to the HIV virus. In an independent study of 120 women, those with an overgrowth of Prevotella bivia bacteria were found to be 20 times more prone to contract HIV than those with lower levels.

The vaginal ring findings is extremely relevant to India where women comprise 39 percent of all HIV infections. It is estimated that a little less than a million women are living with HIV in the country. The incidence of HIV in female sex workers too is considerably high at 2.67 percent. A vaginal contraceptive called Nuvaring, introduced in India in 2009, had found quite a bit of acceptance, but it is nowhere close to the popularity of oral pills.

Sumitra Deb Roy reported from South Africa on a fellowship with the International Reporting Project (IRP).