The Food and Drug Administration (FDA) recently approved lenacapavir for HIV prevention in both men and women. Many experts believe this twice a year treatment could be a game changer in the fight against the HIV epidemic.

To learn more about this breakthrough medication, we spoke with HIV expert Sarah Waldman. She is an associate professor of infectious diseases and director of the PrEP (Pre-Exposure Prophylaxis) Clinic at UC Davis Health.

What is lenacapavir and how does it work?

Lenacapavir is a medicine used to help prevent and treat HIV. It works by blocking the outer shell, or “capsid,“ that the virus needs to protect itself. It also stops the virus from moving into cells and forming together, which keeps it from spreading in the body.

How is lenacapavir different than other preventative HIV treatments?

Lenacapavir is given as a shot every six months. This is different from other HIV prevention medicines, which are usually daily pills or shots given every 4-8 weeks. Lenacapavir is the first approved HIV prevention medicine that only needs to be taken twice a year.

How effective is lenacapavir in preventing HIV?

In two clinical trials called PURPOSE 1 and PURPOSE 2, lenacapavir worked extremely well to prevent HIV infections in both men and women. More than 99.9% of participants taking the twice-a-year shot remained HIV negative during the studies.

These results show that we are on the verge of having one of the best HIV prevention options available since the beginning of the epidemic. It's an exciting step forward.

“These results show that we are on the verge of having one of the best HIV prevention options available since the beginning of the epidemic. It's an exciting step forward.”—Sarah Waldman

Who is eligible to take lenacapavir?

All individuals are eligible for this treatment. While one of the other HIV prevention drugs (DESCOVY) can't be used by people at risk from receptive vaginal sex, lenacapavir can be used by anyone to prevent HIV.

Is it safe to use lenacapavir alongside other HIV medications?

Lenacapavir is always used in combination with other medications to treat an active HIV infection, but it is meant to be used by itself for HIV prevention. Because lenacapavir does not prevent sexually transmitted infections (STIs), it is meant to be used with other safe sex practices, including condom use.

Are there any known side effects of lenacapavir?

The most common side effect in the clinical trials was a reaction at the injection site. Since the shot is usually given under the skin in the abdomen, some people developed a nodule under the skin that was firm and tender. However, the injection site reactions improved over time as people became used to the shots. Other side effects, such as nausea and headaches, were uncommon.

Could lenacapavir help reduce HIV transmission rates overall?

This is one of the best HIV prevention treatments we've had since the start of the epidemic. If used in high-risk communities, it could reduce or even stop the spread of HIV. The best part is it's just two shots a year, so there's no need to take a pill every day. Because lenacapavir is taken less often, the medication could help overcome common barriers, such as frequent clinic visits, and stigma, for preventing HIV infection.

A big concern — locally, nationally, and globally — is who will pay for these medications. It's unclear how we will be able to provide them to the people who need them most.

How can someone go about getting this treatment?

Lenacapavir is expected to be available to the public this fall. If you're interested, talk to your doctor. You’ll need a referral to an infectious diseases clinic, like the PrEP clinic at UC Davis Health, since the shot must be given in a medical setting.