Vaginal Rings - Can Scientists Combine HIV & Pregnancy Protection?

Vaginal ring, intra-uterine device, contraceptive implant and pills
Vaginal ring, intra-uterine device, contraceptive implant and pills. BSIP/UIG/Getty Imges

When vaginal rings were first introduced as contraceptive devices, reactions were mixed. On one hand, they were an innovative new way for people to use hormonal contraception. Blood hormone levels would be lower with local delivery. They were convenient and easy to use. On the other hand, some people were uncomfortable with having to insert them. They were worried about what would happen during sex.

They thought they might be weird or uncomfortable.

Over time, people have gotten more accustomed to the idea of vaginal rings. Some people love them. Other people are less enthusiastic. It is clear, however, that they are easy to use for the people who are willing to use them. Furthermore, they are an effective way to deliver small molecules to the vagina.

The Vaginal Ring and STD Prevention

Hormonal contraception isn't the only way vaginal rings can be useful. In recent years, scientists and researchers have also explored other possible uses for these devices. One such use is for the delivery of drugs and medications. For example, several trials have demonstrated that vaginal rings might be a moderately effective way of delivering pre-exposure prophylaxis against HIV.

Pre-exposure prophylaxis is exactly what it sounds like. People are given medication before they are exposed to HIV. The goal is to reduce the risk of infection were an exposure to happen.

In general, most pre-exposure prophylaxis (or PrEP) studies are done in at risk gay men and sero-discordant heterosexual couples.

The first generation of PrEP research was highly successful. It showed that taking antiretroviral drugs could reduce a person's risk of HIV exposure. However, that only worked when people took the drugs regularly.

Unfortunately, not everyone was compliant.Therefore, researches set out to find ways to make taking these medications easier. One such method was delivering them via vaginal ring.

Using  a vaginal ring for PrEP is the same as using one for contraception. A woman inserts the flexible polymer ring into her vagina and it releases the medication automatically. The ring is then changed at regular intervals.

Early research suggests that a ring containing antiretroviral medication can reduce HIV risk. However, in the human  studies that have been reported so far, the rings did NOT eliminate risk. It is possible that future formulations may have a greater efficacy, as has been seen in studies in monkey models. Different combinations or classes of drugs may turn out to work better... or worse.

There is not yet a vaginal ring containing HIV medication on the market,. Still, one may well be released  in the foreseeable future. Even more exciting is the fact that doctors and scientists are talking about the possibility of making dual purpose rings.

It would be relatively straightforward to make a device that had both contraceptive properties and anti-HIV properties. That could represent a sea change in prevention. However, it's worth noting that such a product would only protect against HIV and not other STDs. It wouldn't be a magic bullet. It still could make a big difference in many women's lives.

Sources:

Baeten, J.M., et al. and the MTN-020 ASPIRE Study Team. Use of a Vaginal Ring Containing Dapivirine for HIV-1 Prevention in Women. New England Journal of Medicine. 2016 February 22. Published Online Ahead of Print. doi:  10.1056/NEJMoa1506110

National Institutes of Allergy and Infectious Diseases. Vaginal Ring Provides Partial Protection from HIV in Large Multinational Trial. 2016 February 22. Accessed 2/22/16 at http://www.niaid.nih.gov/news/newsreleases/2016/Pages/ASPIRE.aspx

Smith JM, Rastogi R, Teller RS, Srinivasan P, Mesquita PM, Nagaraja U, McNicholl JM, Hendry RM, Dinh CT, Martin A, Herold BC, Kiser PF. Intravaginal ring eluting tenofovir disoproxil fumarate completely protects macaques from multiple vaginal simian-HIV challenges. Proc Natl Acad Sci U S A. 2013 Oct 1;110(40):16145-50. doi: 10.1073/pnas.1311355110.

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