Top-Up

What was this study about?

The most common way in which HIV (the Human Immunodeficiency Virus) is spread is through sexual contact between men and women. Although condoms offer very good protection, it is not always possible for a woman to get her partner to use them. So there is an urgent need for other methods of protection that women can use to protect themselves.

Microbicide gels are one such method. These gels may prevent women becoming infected with HIV during sex if they are put in the vagina. A number of studies looking at whether these gels are safe and whether they work have already been carried out, and others were ongoing at the time of Top-Up.

Some microbicides that were planned for testing must be inserted into the vagina before every sex act. The disadvantage of this is that sex is sometimes unplanned, so women don’t always know when to insert gel. Some of the new microbicides that are being developed can be inserted every day, whether women are planning to have sex or not. This may make the gels easier to use.

Before we can test whether or not daily microbicides work, we needed to do a study to find out whether daily use would be acceptable to women. We were also interested to find out the best way to collect in used applicators which was the way we measured how well women took the gel. To assess this women were randomised to return applicators daily, weekly or at the monthly visit. This is what the Top-Up study was about.

In the Top-Up study we wanted to find out what women think about using a microbicide gel every day, whether this was acceptable to them, and what the best way was to ensure that they used the gel.

The gel used in Top-Up was not an active microbicide. It was a placebo gel with no activity against HIV. The Top-Up study tested the process of getting women to use a gel every day and return the used gel applicators. It also aimed to find out what men thought about their partners using a gel every day.

What difference did this study make?

Women who were randomised to the daily return were more likely to drop out of the study. Although we can’t be sure, this suggests they did not like the daily return. Those who remained in the study had similar levels of applicator use to the women in the other groups and this was 85-88%, so very high, which we were quite surprised about.

Type of study

Randomised trial

Who funded the study?

Top-up is funded by the UK Department for International Development (DFID), the UK Medical Research Council (MRC), the European and Developing Countries Clinical Trials Partnership (EDCTP), CONRAD and the International Partnership for Microbicides (IPM).