Human immunodeficiency virus (HIV) is a major cause of illness. It particularly effects men who have sex with men (MSM) and trans women. Most studies of HIV and HIV pre-exposure prophylaxis (PrEP) lump MSM and trans women into one group. As if gay men, bisexual men, and trans women all have similar risk factors. In fact — they don’t. They are very, very different groups.
For most of the history of HIV, barrier methods and abstinence have been the only ways to prevent the spread of HIV. Today we have treatment-as-prevention and pre-exposure prophylaxis. Treatment-as-prevention involves treating people affected with HIV with HIV-suppressing medications. By reducing the number of viruses a person is carrying around with them, the chances that any one virus can infect another person go down.
Pre-exposure prophylaxis (PrEP) has been available since 2012. It involves taking an HIV-suppressing drug every day. That way, if an HIV virus actually comes into contact with that person the virus won’t be able to infect them. Only one medication is currently approved for use in the United States, and that is Truvada. PrEP prevents HIV infection when taken every day at the same time. All HIV infections that have happened to date while a person was on PrEP occurred because the person took PrEP inconsistently.
This week we look at a study exploring the use of PrEP and HIV risks among trans women specifically. To my knowledge no study until this one has separated out MSM and trans women.
This is important! Not only are trans women at high risk for being infected with HIV…but there have been few HIV prevention guidelines and interventions directly targeting trans women. Both the WHO and CDC HIV PrEP guidelines do not include trans women.
This paper examined data from the iPrEx study, which was a study of the use of PrEP among people assigned male at birth in the US, Brazil, Ecuador, Peru, South Africa, and Thailand. This paper in particular examined differences between trans women and MSM in the iPrEx trial.
What kinds of things did they find?
First — 15% of the participants in the trial were trans woman. They either identified explicitly as trans, or identified as a woman when asked. Compared with MSM participants, trans women were more likely to…
- less education
- have more sexual partners and have a history of sex work (64% vs 38% of MSM)
- more likely to live alone (23% vs 14%)
- less likely to use a condom for receptive anal sex (14% trans women used a condom vs 45% of MSM)
- were more likely to use cocaine or methamphetamine (11% vs 7% of MSM)
Not the most heartening information, but also not brand new. It’s been known for a while that trans women do participate in sex work out of lack of options. Higher numbers of sexual partners, lower levels of condom usage, sex work, and substance use are all associated with HIV infection.
What about PrEP and HIV though? Trans women not on hormone therapy and MSM had similar levels of PrEP in their blood. That means they were taking the medications regularly and the medication was doing what it’s supposed to. And this wasn’t because of a hormone effect. The researchers did ask the participants how often they were taking their PrEP. Trans women on hormones were less likely to report always using PREP.
All the trans women who did become infected with HIV during this trial were taking PrEP at the time. In contrast, all the trans women who took PrEP regularly did not become infected with HIV.
It’s also good to note that there were no adverse drug effects noted in this trial. The PrEP medications did not cause significant harm. There were some changes to liver function tests and kidney tests. However those changes didn’t cause medically noticeable harm.
So what are the take-aways here?
- PrEP in trans women works when taken daily.
- There are significant differences between trans women and MSM. They should not be lumped together in one group.
- Further research on potential interactions between PrEP and hormone therapy should be done. This is just to be safe — we want to make sure that PrEP doesn’t effect hormone therapy and that hormone therapy doesn’t effect PrEP
Lastly — if you or your partner(s) are at risk for HIV infection, talk with your doctor about whether PrEP is right for you. It’s a great option in the fight to prevent HIV infection.
Want to read the study for yourself? The abstract is publicly available