The reduction in HIV transmission in the PrEP, TDF2 and iPrEX trials clearly supports the use of antiretroviral therapy among uninfected people in serodiscordant relationships, but efforts to prevent HIV transmission should not merely be about writing a prescription. We need to continue to talk to our patients about the importance of condom use and minimizing exposure by having sex with as few partners as possible. Antiretroviral therapy should be viewed as additional insurance within a multipronged prevention strategy.
Dr. Donna E. Sweet
The rates of transmission reduction in all three trials were impressive and certainly game changing. But it is important to appreciate that the active treatment group participants in the studies received, in addition to medication, intensive risk-reduction education and follow-up. I call it the pill plus. And that’s what we need to achieve in clinical practice.
So what are the drawbacks of giving antiretroviral therapy prophylactically?
Providing antiviral prophylaxis may encourage disinhibition among some individuals who feel that taking a pill protects them from the consequences of risky behavior. There may be people who become infected because they take therapy just on the weekends when they anticipate being sexually active and don’t comply fully with the regimen.
Yet these possible risks might be acceptable within the context of failed prevention efforts thus far. Each year, there are 56,000 new HIV infections in the United States and 2.5 million new infections worldwide.
Resistance is another concern. If people taking tenofovir and emtricitabine (Truvada) prophylactically become infected, they could develop resistance to these drugs before their infections are detected. Frequent HIV testing is necessary so that physicians can add additional medications if the patients become positive to minimize the risk of resistance. Guidelines from the Centers for Disease and Prevention recommend HIV screen for this group every 3 months, but that may not be frequent enough.
And then there are the costs of therapy, which are considerable. Coverage for an uninfected population would not be covered under the Ryan White Care Act and it remains to be seen whether Medicaid and private insurance will pay for the drugs. Prophylactic therapy may be within reach of only those who can afford to pay for it out of pocket.
I have yet to have many of my uninfected patients request prophylactic therapy, but I’m sure they will when the results of these studies become more widely known. And when they do, physicians in primary care are clearly going to have to become more comfortable in managing HIV infection risks. There already is a shortage of providers in HIV care and people are not going into it at the rate that they used to. I worry about what will happen when my colleagues and I eventually age out and no one steps in to replace us. At the same time, primary care providers are well positioned to manage the increasingly chronic nature of the HIV infected population. Helping these patients combat the development of heart disease and diabetes is now a big part of what HIV patient management is about and primary care providers are well suited for this challenge. They will also be on the forefront of "biologic prevention" – pills taken by the uninfected to remain uninfected.
Dr Sweet is professor of internal medicine at the University of Kansas, Wichita. She serves on the board of Internal Medicine News. She reported having no conflicts of interest.