Ask the Doc: Truvada and PrEP
This week, we take a look at Truvada and PrEP, pre-exposure prophylaxis, with EDGE Media Network's resident HIV expert, Dr. Joel Gallant, associate director of the Johns Hopkins AIDS Service at Johns Hopkins School of Medicine. Send your questions on HIV healthcare to him at firstname.lastname@example.org
Is There a Vaccine for HIV Now?
Q: I heard there is finally a vaccine to prevent HIV.
A: Not a vaccine -- we're a long way from that. You may be referring to pre-exposure prophylaxis ("PrEP"), the use of antiretroviral medications by HIV-negative people to prevent infection. Truvada (the single tablet combination of tenofovir and emtricitabine) has just been approved by the FDA for that purpose. In clinical trials, people who took it every day were much less likely to get infected that those taking a placebo. Adherence was critical: some participants got infected even though they were randomized to the Truvada arm. Most had no detectable drug levels in their blood because they weren't actually taking the medication.
Truvada is well tolerated, but it can cause kidney problems, so regular laboratory monitoring is critical. There's also concern that people who get infected despite taking PrEP may develop drug resistance. So far that's happened only to those who had acute infection when they started taking PrEP. Clinicians must screen PrEP candidates for HIV and ask about symptoms of acute infection before prescribing Truvada.
There are many unanswered questions about PrEP:
1. Who will prescribe it? HIV providers know the drugs well, but are busy taking care of HIV-infected patients. Primary care doctors will need to learn how to prescribe PrEP, monitor for Truvada toxicity, and screen regularly for HIV infection, assuming they're willing take this on.
2. Who will pay for it? Even before FDA approval, Truvada was being prescribed by some doctors for prevention. It's usually covered by private insurance companies, whether you have HIV infection or not. For everyone else, coverage is less certain, and there are no government programs in place now to pay for PrEP for the uninsured. Gilead Sciences, the manufacturer of Truvada, will offer an assistance program that may help people who have no other way to pay for the drug.
3. Who should take PrEP? Will it cause people to have more unsafe sex? See my answer to the next question.
PrEP or Condoms: Do I Really Have to Choose?
Q: I'm a single, HIV-negative gay man. When I have sex, I try to use condoms if I'm on the bottom, but it doesn't always happen. I went to my doctor to ask about PrEP and made the mistake of telling him I might use condoms less often if I took it. He told me he couldn't prescribe PrEP unless I promised to use condoms. What do I do now...find a new doctor and lie?
A: Your doctor is expressing a commonly voiced concern: that PrEP will cause people to stop using condoms and have more unsafe sex. You were honest with him and admitted that was likely to happen in your own case. But like many gay men, you're already having unsafe sex. He should have recognized that you're at high risk, talked to you about PrEP, and then advised you that condoms are still a good idea. Instead, his message is that you can't take PrEP unless you either use condoms or lie to him about using condoms. The problem with this approach, besides the fact that it discourages honesty between patient and physician, is that people who consistently use condoms are already protected and don't need PrEP.
PrEP was developed because we need a form of prevention for HIV-negative people who don't consistently use condoms. Physicians shouldn't be moralistic, withholding an effective form of prevention from someone who refuses to behave according to their standards. They should focus on what's best for the patient, which in this case is to prevent HIV infection.
PrEP is a very expensive way to prevent HIV infection; Truvada isn't something we should be putting into the drinking water. You could give PrEP to people who always use condoms, or to the monogamous, HIV-negative partners of HIV-positive people who are taking effective treatment, but those people are at very low risk already. The only way PrEP will ever be cost effective is if we prescribe it to the people at the highest risk of infection. Gay men who are having unprotected sex with multiple partners are exactly the people who should be taking PrEP.
Should you change doctors? Maybe...unless showing him my answer causes him to rethink his approach.