HIV transmission on PrEP is possible, but very rare, according to new study.

A Man Has Contracted HIV While on PrEP. What This Means—and Doesn’t—for the Future of HIV Prevention.

A Man Has Contracted HIV While on PrEP. What This Means—and Doesn’t—for the Future of HIV Prevention.

Expanding the LGBTQ Conversation
Feb. 26 2016 4:52 PM

PrEP Is Not Magic—and Treating It That Way Undermines Its Incredible Power

Truvada, the drug currently used for PrEP.

Photo by DENIS CHARLET/AFP/Getty Images

It’s been a confusing week with regard to PrEP—an HIV-prevention strategy which currently consists of taking a daily pill (Truvada) to prevent infection if one is exposed to the virus.

J. Bryan Lowder J. Bryan Lowder

J. Bryan Lowder is a Slate associate editor. He covers life, culture, and LGBTQ issues.

At a major conference for HIV research—the Conference on Retroviruses and Opportunistic Infections—the CDC revealed that, if deployed widely alongside pushes for more HIV testing and treatment, PrEP has the potential to help reduce new infections in the U.S. by 70 percent, preventing an estimated 185,000 new cases by 2020. Specifically, suppressing the virus to “undetectable”—and therefore essentially nontransmissible—levels in HIV-positive people could prevent 168,000 infections, while an expansion of access to PrEP to negative individuals could forestall 17,000 new cases.


Those numbers add to the promise of PrEP, which has been shown to be 99 percent effective at preventing HIV transmission if taken daily as directed. But of course, that statistic leaves a 1 percent chance of infection open—and, unfortunately, an instance of that 1 percent also showed up at the conference.

David C. Knox, a physican and researcher from Toronto, presented a case study of a patient who, according to the doctor, represents “the first reported case of breakthrough HIV infection with evidence of long-term adherence to PrEP.” The patient, a 43-year-old man, had been on PrEP for about two years (testing negative for HIV seven times as part of the regular checkups required for the regimen) when he seroconverted. Importantly, pharmacy records and further medical investigations confirmed his claim that he had been taking the medication as prescribed. (Cases of infection in PrEP patients who had not kept up with the daily pill have been reported; this is the first time an apparently compliant individual has seroconverted.) The patient reported multiple instances of anal sex without condoms in the period before testing positive. While PrEP’s protection rates are actually higher than those for condoms, it is currently recommended that individuals on the program continue to use them, as condoms help protect against other STIs and enhance coverage for HIV.

To the scientific community, this is an intriguing—though rare—case of HIV multi-drug resistance. The patient’s particular viral pool showed varying levels of resistance to a host of drugs, including those that make up Truvada—though he is now on a customized regimen rendering him undetectable. In the presentation (which is streamable online), Knox suggested that the patient was likely infected by an HIV-positive partner whose own treatment on the drug cocktail Stribild was “failing,” or losing efficacy, as sometimes happens for various reasons over the long term.

It’s important to note that the resistance of this particular instance of the virus is extremely uncommon. Speaking to Betablog, Dr. Robert Grant, a noted HIV/AIDS researcher, provided some helpful context:

The prevalence of this kind of virus among recently infected persons is less than 1%. Maybe much less. If PrEP is not fully effective against viruses that are HIGHLY resistant to both drugs in FTC/TDF PrEP, the efficacy of PrEP when taken may decrease from 99% to 98%. Or from 99.9% to 98.9%. Or from 100% to 99%. The decimal points are not certain. My point is that one chooses whether to focus on the glass 99% full or 1% empty.

Still, the news has caused a great deal of consternation among gay/bi men and the wider PrEP constituency, both among advocates who fear a scientifically unfounded “told-you-so” reaction from PrEP opponents like the AIDS Healthcare Foundation, and among individuals currently taking or curious about PrEP and unsure of what to make of such an unsettling report. The latter anxiety is understandable, but ultimately unwarranted—such a case was essentially guaranteed to surface at some point. All that’s changed is that a percentage point has unfortunately become a person.

That shift does not negate PrEP’s efficacy or importance as an HIV prevention tool. In fact, it just confirms what we already knew about its limitations—limitations that remain, well, amazingly limited. But it does offer two useful takeaways.

The first is rather obvious: PrEP is powerful, but, as a series of ads on buses and trains in New York are currently putting it, “PrEP + condoms” is even more powerful. While there’s no way of being certain, that double-up strategy might have helped this patient avoid his seroconversion, and it undoubtedly could help prevent similar situations for others. In a certain sense, it’s an embarrassment of riches to have two incredibly effective methods for preventing HIV transmission (and three if you count treatment-as-prevention) at our disposal. Yes, sex is complicated, condomless sex isn’t inherently “bad” (though nor is it inherently transcendent), and we all should feel empowered to make decisions appropriate to the situation. But if this dispatch from the 1 percent gives you pause, using both is probably a good idea.

But more important, the heated response to this news has revealed a fundamental problem in the way many of us, from advocates to detractors, have been thinking and talking about PrEP. It has taken on an aura of the magical. For some skeptics, the pill is a cursed object, capable of turning gay men into irresponsible “sluts” or “partiers” and vexing the fragile recovery the community achieved after the initial AIDS crisis was quieted. And for some supporters, it’s an amulet, imbuing the holder with imperviousness and warding off fear, even the sort that might be healthy. These twin responses make sense for a community that suffers from group trauma—discovering sex and death in bed together isn’t an experience you easily shake. But they are both ultimately inaccurate, as all magical thinking must be. Truvada is not a hex or a charm; it’s a drug. It is not magic; it’s medicine.

Medicines work, and medicines fail—we usually understand this, cheering the former and mourning the latter. That we find PrEP’s exhibition of the same behavior to be some kind of betrayal or portent suggests we’ve lost sight of that logic in this case. Let’s use this opportunity to get it back. Let’s discuss PrEP with nuance, fighting for those who need it while avoiding the allure of generalization. Let’s ask smart questions about its impact on the community in a way that embraces the complexity of reality rather than retreating into the ease of the metaphysical. The awesome is always intimidating, regardless of whether it’s beautiful or terrible, and intimidation is not what we need right now. PrEP was never going to save us, not entirely, nor was it going to end us—but what good it can do will be hampered by freighting it with powers it does not possess and responsibilities it cannot bear.