On Tuesday, the Journal of the American Medical Association published a study on antiretroviral therapy (ART) and HIV transmission in mixed status couples — couples where one partner is HIV positive.
The HIV positive partners included in the study were already on ART, and the couples who participated — which were 61.7 percent heterosexual, and 38.3 percent MSM (men who have sex with men) — did not plan to use condoms, though they were encouraged to do so in doctor visits.
The results were groundbreaking.
"There were no documented cases of within-couple HIV transmission," the study reports. The authors concluded that taking antiretroviral drugs diligently was an extremely effective way to prevent HIV transmission, even when condoms were not used.
ATTN: reached out to Vice Chair of Global Health at the University of Washington School of Public Health Dr. Jared Baeten, MD, PhD — who specializes in HIV/AIDS research — to get his take on the study and learn more about HIV transmission, ART therapy, and PrEP — an FDA approved drug that an HIV negative partner can take to prevent transmitting the virus from an HIV positive partner.
ATTN: Before we get into the JAMA study, I was wondering if you might share some best practices for dating somebody who is HIV positive if you are HIV negative?
The most important part I consult patients about is about having open and honest conversations with the people they are dating and their sexual partners, and understanding what information there is, and making open and honest decisions with their partners about the sexual choices they are going to make.
ATTN: Are there any particular sexual behaviors you would advise people to avoid?
I think greatest risk for getting HIV is truly having sex with someone whose HIV status you do not know, and not having open and honest conversations about HIV and HIV status, and then if someone has HIV, their treatment status. But I think potentially the greatest risk is assuming that people don't have HIV, or not wanting to think about HIV or just not having the conversation about it.
ATTN: Recently there's been more awareness about PrEP. Is that something you would recommend for someone in a romantic or sexual relationship with someone who is HIV positive? What should they know about how it works and how effective it is before they make that decision?
PrEP is a way for a person who doesn't have HIV to protect themselves from getting it, and it involves taking a pill that is anti-retroviral, and anti-HIV medicine and that will block the virus from taking hold. For people who are at risk of getting HIV, PrEP is an option, and a very good option, when taken well and consistently. The evidence suggests that PrEP’s protection is in excess of 90%. For someone who has partners of unknown HIV status, or partners who are known to be HIV positive and aren't on medicine, PrEP is definitely an important option.
There's both PrEP — a medicine for an HIV negative person to keep them HIV free — and treatment for people who have HIV, and that is to treat the virus and keep them healthy, but also make them less infectious to their partners, much less infectious. Both PrEP and treatment work incredibly well together to prevent infections, and I think all of the data that we have emphasizes that they work incredibly, incredibly well. I think what is important is that both PrEP and treatment offer an opportunity for an individual to take control of their own HIV risk.
ATTN: I was looking at this JAMA study that was published on Tuesday, on antiretroviral therapy in primarily heterosexual couples where one partner is positive. Does that kind of therapy — the drugs that a person would take if they are HIV positive — work differently from PrEP?
The medicine that we use for PrEP are some of the medicines we use for treatment as well. [It’s the] same medicine, and they work by blocking the virus from making copies of itself. When it's used for PrEP, it's used by somebody who doesn't have HIV. So that medicine — by being in their bloodstream and being in their body — if they come in contact with the virus, it blocks it right away.
For treatment, which you read about in that study, the person who was infected was on treatment. Some of them undoubtedly used the same medication we used for PrEP plus other medications for their treatment. But in their case, it worked by turning their virus off, which is what treatment does, it turns the virus off in someone who is HIV positive.
ATTN: Is there any sort of difference that you have observed, or research that has indicated, how well treatment works in heterosexual versus homosexual couples? Is there any reason that the studies primarily conducted on heterosexual couples wouldn't apply to homosexual couples?
Transmission between men in homosexual couples seems to occur sometimes more easily than heterosexual couples, so it might be harder to block. There's been some very nice studies of heterosexual couples that have really shown well that treatment works very well for preventing passing of the virus.
But treatment works very well for turning off the virus in everyone, regardless of who they are having sex with. That's the main reason treatment works for prevention: it turns off the virus and makes the person less infectious. It's not completely known whether [drugs work by ] turning the virus far down or turning it off, [and] then if that man has sex with another man, if that risk is 0 or if it is near 0.
But I think what is clear in the study, no matter who you are, if you have HIV and you are on treatment, you cut your chances dramatically of passing the virus to anyone else. And in fact, the very strongest way to cut your chances is to take your medicine and take it consistently, it works incredibly well.
ATTN: How long has PrEP been available?
PrEP has been studied for the last ten years, but the major studies that proved that prep worked for HIV prevention finished in the 2010-2011 range. The Food and Drug Administration approved the one medication that is branded for PrEP in July 2012.
Since that time, there has been a growing awareness of and interest in use of prep. I do a lot of PrEP research myself, but in the US, there was limited awareness and limited use in 2012, and it has been growing and then accelerating and increased dramatically in the last couple of years. And so now PrEP has good use in many places and undoubtedly has a major impact and important impact.
ATTN: What does the cost look like? Do you think it is reaching the people that it needs to reach or can the cost be a concern?
Like everything with medical care, cost is a really important consideration. PrEP medicines have an important cost to them, but in many settings and in my experience, PrEP medications are covered by insurance, or in some states are covered by drug systems, programs or other things that can make PrEP more affordable for many, many more people.
ATTN: Have you seen an increase in the mixed-status relationships in recent years, and since PrEP has become more widely available?
Certainly anecdotally. I have certainly had patients who have told me about that, and have told me many, many different kinds of conversations that they have had with partners, now that both PrEP and treatment benefits for prevention have become more widely known.
Both PrEP and treatment go together in very complimentary ways, and very synergistic ways. And as PrEP has become more used and the benefits for treatment become more clearly known, I think there are more zero difference partnerships, where one partner is infected and the other uninfected, and there are many conversations about that.
I am not sure what the data is on that, but I certainly have heard in informal settings, in the patients I have seen, and other ways, I have heard having much more discussion along those lines.
ATTN: Is there anything else you would want either partner in a mixed status relationship to know before having a sexual relationship?
I will reiterate this, I think it's important for people to know what their options are, to know what the information is, and to be able to have open and honest discussions with each other, and with their doctors, about weighing the risks, benefits and prevention options.