Fact #1: New diagnoses of HIV dropped by almost 20% from 2008 to 2015.
Fact #2: Pre-exposure prophylaxis (PrEP) uptake increased dramatically during the same period.
Cause and effect or happy accident? A team from Emory University and the neighboring Centers for Disease Control and Prevention (CDC) think it is the former. Using the National HIV Surveillance System and a U.S. prescription database, this team ranked U.S. states and Washington, D.C., by their estimated annual change in HIV diagnoses, as well as their use of PrEP by those with an indication for PrEP. Then, they placed each into quintiles to look at associations between PrEP use and new HIV case reports. Lastly, to isolate the effect of PrEP on new diagnoses from the naturally preventive effects of successful treatment, data on viral suppression available from 38 jurisdictions were also evaluated.
In the lowest PrEP uptake quintile, the estimated annual percent change in HIV diagnoses increased by 0.9%. In stark contrast, among the ten jurisdictions with the greatest uptake of indicated PrEP, the annual percent change in HIV diagnoses dropped 4.7%. For the quintiles between these extremes, the change in new diagnoses followed this trend. Controlling for viral suppression rates did not significantly alter these findings.
Interestingly, in 2016, the rate of PrEP use was more than three-times greater in the highest quintile of PrEP use than the lowest quintile (110/1000 versus 35/1000).
The Bottom Line
Back in the days before potent combination therapy, long before any talk of broadly neutralizing antibodies, kick and kill, or long-acting injectables, news of the discovery of a pill that could prevent a person from acquiring HIV would have been second only to a cure as a cause for mass euphoria. Maybe it is because of these other advances that PrEP's reception has been so muted.
These data support a major role for PrEP, along with treatment as prevention, as a driver of the remarkable declines in new HIV diagnoses. But while the investigators nicely show where PrEP use has expanded and where it has not, neglected is a discussion about who is being left out.
PrEP is most available to white men who have sex with men (MSM). The rate of HIV diagnoses increased in MSM of color during the same period covered in this analysis -- and, of course, African Americans and Latinx are also less likely to be on PrEP. Having PrEP be available and acceptable to all at-risk should not be this difficult.
On the supply side, many are breathlessly preaching PrEP to all potential prescribers who will listen -- often to silence or indifference. On the demand side, things are complicated. Certainly, a pill-a-day prevention strategy has limitations -- just ask anyone on lifelong antihypertensives or diabetes medications, or women who take oral contraception. Survey data show that some are not into a daily pill; in addition, the costs associated with being on PrEP and an under-appreciation of HIV risk are powerful forces.
Lack of money and lack of knowledge are obstacles to effective means to protect health and well being for people living in the U.S. The failure to make PrEP more widespread smacks of moral lethargy, complacency, and a bankruptcy of leadership -- especially after this important piece of evidence. How about we "Make America Healthy Again"?
David Alain Wohl, M.D., is a professor of medicine in the Division of Infectious Diseases at the University of North Carolina (UNC). He is site leader of the UNC AIDS Clinical Trials Unit at Chapel Hill, director of the North Carolina AIDS Education and Training Center (AETC), and co-director of HIV services for the North Carolina state prison system. In 2014, he became co-director of the UNC-Duke Clinical RM Ebola Response Consortium.