Dapivirine vaginal ring for PrEP

What is PrEP?

PrEP stand for pre-exposure prophylaxis. This means preventing HIV by taking anti-HIV drugs.

How does it work?

The anti-HIV drug in the vaginal ring stops HIV from entering cells in the vagina, so stops HIV from entering the body. You need to keep the ring inside you for a month at a time to make sure that the drug maintains high levels in your bloodstream to prevent HIV infection.

The ring only protects against HIV during vaginal sex. It does not provide protection during anal sex.

What is the dapivirine vaginal ring?

The dapivirine vaginal ring is sometimes called the PrEP ring or the DapiRing. It is a flexible silicone ring that is placed in the vagina and releases the anti-HIV drug dapivirine over the course of a month. The ring is available as an alternative to taking tablets for women who are unable to take daily PrEP tablets.

Vaginal rings which provide contraception are also available, but the dapivirine vaginal ring is not a contraceptive.

What other types of PrEP are there?

The most widely used form of PrEP is a tablet containing tenofovir disoproxil / emtricitabine, and there’s also an alternative PrEP tablet containing tenofovir alafenamide / emtricitabine.

There are also long-acting PrEP injections containing cabotegravir or lenacapavir.

Not all the types of PrEP are available in all countries.

What’s the difference between PrEP and PEP?

You start to take pre-exposure prophylaxis (PrEP) before you are exposed to HIV and continue to take it for as long as you need it, to protect against infection. You take post-exposure prophylaxis (PEP) after you have been exposed to HIV, for a fixed period of one month.

Effectiveness

The dapivirine ring was tested in a large study in 2629 women in southern and eastern Africa in which women were randomly assigned to use a ring containing dapivirine or a ring without any active drug. Using the dapivirine ring reduced the risk of acquiring HIV by 37%. Using the ring every day reduced the risk of acquiring HIV by at least 75%.

Is this type of PrEP available to me?

The dapivirine vaginal ring has been approved by drug regulators in Botswana, Eswatini, Kenya, Lesotho, Rwanda, South Africa, Uganda and Zimbabwe. It is likely to become available in other African countries in the next few years.

Services which provide HIV testing, treatment for sexually transmitted infections or treatment for HIV may also provide PrEP – or have information on local services which do.

Although the ring has been approved by the European Medicines Agency, there are currently no plans to market the ring in Europe or other high-income countries.

Tests before starting to use the ring

You need to have an HIV antibody test to check that you don’t have HIV already.

How to insert the ring

The ring can be inserted standing, squatting or lying down, whichever is most comfortable for you.

Twist the ring into the shape of the number eight between your thumb and forefinger. This will make it easier to insert.

Using your other hand, hold open the folds of skin around the vagina. Gently push the ring into your vagina as far as you can with your finger.

The ring needs to be in the vagina for several hours before it begins to provide protection against HIV. Protection stops within a day after it is removed.

The ring does not need to be removed for cleaning after sex or during menstruation. Removal of the ring during menstrual periods will lead to lower levels of dapivirine in the vagina and loss of protection against HIV.

What to do after accidental removal or expulsion

If the ring comes out accidentally, you can rinse it in clean water and put it in again. If the ring falls into the toilet, insert a new one.

Will I be able to feel the ring once it is inserted?

The vaginal ring is safe and comfortable to use regularly. In trials, at least eight out of ten users said they were never aware of the ring during everyday activities. Nine out of ten users said they found the ring was comfortable during daily use. Three out of four users never felt the ring during sex and seven out of ten women said their sexual partners did not feel the ring during sex. When the ring is inserted correctly, it should sit near the cervix and not come into contact with the penis during sex.

Disposing of the ring

After one month of use, remove the ring and wrap it in a tissue or the empty pouch. Then dispose of it in a refuse bin, out of the reach of children. The ring should not be flushed down the toilet.

Check-ups while using the ring

Regular checkups are important while using the ring.

You should have an HIV test every three months, to check that you remain HIV negative. You may be offered an extra test one month after starting to use the ring, to check that you didn’t acquire HIV just before starting PrEP. It is best to be tested for HIV using a fourth-generation antibody-antigen test. These are more sensitive than rapid antibody tests and will detect HIV sooner. The majority of people who acquire HIV will receive a positive result using a fourth-generation HIV test within four weeks of exposure.

Rapid HIV tests which use a sample of moisture from the mouth do not always pick up recent infections, so should not be relied on while using PrEP.

You may also have tests for other sexually transmitted infections at these clinic visits.

If you are not using the dapivirine vaginal ring and you have flu-like symptoms, possibly with a rash, within a month of condomless sex, this may be a symptom of HIV infection. You should have a fourth-generation HIV test a month after the most recent exposure and delay using the vaginal ring until you have been confirmed HIV negative.

If you have just started using the dapivirine vaginal ring and you have flu-like symptoms, possibly with a rash, this may be a symptom of HIV infection. Contact your clinic immediately to arrange a fourth-generation HIV test and/or viral load test.

Using the ring during pregnancy, breastfeeding or when you are trying to conceive

The available data suggests that the ring is safe to use during pregnancy and breastfeeding, and when trying to become pregnant. Dapivirine is found in breast milk at very low levels and does not cause harm to the infant.

Who shouldn’t use the ring?

• People living with HIV.
• Girls under the age of 15 (due to a lack of evidence of safety).

Side effects

The dapivirine vaginal ring has few side effects and is well tolerated by most users. The most common side effect (affecting at least one in ten users) is urinary tract infection.

Other common side effects (affecting at least one in a hundred users) are:

• Vaginal discharge
• Itching in the vagina or vulva
• Pelvic pain.

Side effects are most likely to occur during the first month you are using the ring. If you have side effects which don’t go away or get worse, speak to staff at your clinic.

Interactions with other medicines

When two drugs are taken at the same time, their interaction can affect the drugs’ effectiveness and side effects.

Only a tiny trace of dapivirine from the vaginal ring enters the bloodstream so there is no risk of interactions with medicines taken by mouth. There is a possibility of interactions with other medical products applied to the vagina.

The dapivirine vaginal ring does not interact with:

• Alcohol or recreational drugs
• Gender-affirming hormones
• Hormonal contraception.

The University of Liverpool provides an online tool to check for interactions between anti-HIV drugs (including PrEP) and other medications. You enter the names of your PrEP drug (dapivirine) in the left column, and the other medications you are taking in the next column. The results are provided with a traffic-light system: if the result is red or amber, it’s worth checking with your doctor or pharmacist. If it’s green, there shouldn’t be any problem. Visit www.hiv-druginteractions.org/checker or download the Liverpool HIV iChart app for iPhone or Android.

Contraception

The dapivirine vaginal ring does not prevent pregnancy, so you may need to also use contraception if you do not want to be pregnant. The ring does not reduce the effectiveness of oral hormonal contraceptives or long-acting injectable hormonal contraception.

Nonetheless, the dapivirine vaginal ring is not suitable for use at the same time as the contraceptive vaginal ring or the diaphragm.

Drug resistance

Some people worry that while taking PrEP they may get drug-resistant HIV. It’s important to remember that HIV drug resistance can only happen if you take PrEP when you already have HIV. This is why you should get tested for HIV before you start PrEP, and keep testing regularly.

Resistance hasn’t been a problem in vaginal ring studies so far. Among women who used the dapivirine ring when they already had HIV, there was no increase in cases of drug resistance.

Does the ring prevent STIs?

PrEP does not prevent other sexually transmitted infections so it’s a good idea to have regular tests for sexually transmitted infections while you are taking PrEP.

References

Full image credit: Vaginal ring. Image by NIAID. Available at www.flickr.com/photos/niaid/25153111944 under a Creative Commons licence CC BY 2.0.