PrEP Coverage Associated with Decreased HIV Diagnoses

The number of new diagnoses of HIV in the United States has decreased in association with increases in pre-exposure prophylaxis (PrEP) coverage, new research found.

Using data from the US National HIV Surveillance System from 2012-2016, the study, published in Clinical Infectious Diseases, examined viral suppression (VS) and annual percentage change in diagnosis rate (EAPC). It also estimated PrEP uptake with data from a national pharmacy database.

“Even when controlling for increases in viral suppression, increases in PrEP coverage have a statistically significant association with jurisdictional decreases in annual HIV diagnosis,” Dawn K. Smith, MD, MPH, MS, epidemiologist and medical officer in US Centers for Disease Control and Prevention’s Division of HIV/AIDS Prevention told Contagion®. “This supports the efficacy of bringing PrEP use to scale in the US to accelerate reductions in new HIV infections.”

States that saw the greatest increases in PrEP coverage saw an EAPC drop of 4.0% (95% CI, -5.2% to -2.9%), and the overall average EAPC decrease for a given year was 1.1% (95% confidence interval, -1.77% to -0.49%) for an increase in PrEP coverage of 1 per 100 people indicated for PrEP use. When controlling for viral suppression, the average EAPC decrease was 1.3%.

“Our results strongly support the urgency of expanding PrEP delivery to as many as possible of the 1.2 million persons at substantial risk for HIV acquisition,” Smith told Contagion®. “This includes all transmission risk groups, providing equitable access for all racial/ethnic groups, and focusing on the regions where the rates of HIV infection are highest.

“In the US, annual HIV diagnoses are occurring at the highest rates among black men and women and men who have sex with men of all race/ethnicities, yet PrEP coverage is highest among white men and women.”

The study noted that the number of HIV diagnoses in the United States has decreased slowly since 2008 while remaining stable or increasing in certain groups. Overall, HIV diagnoses plateaued from 2013 to 2016. Efforts to fight the disease have included expanding sustained antiretroviral therapy (ART) and oral PrEP for those at high risk based on sexual or drug injection behaviors.

The US Food and Drug Administration approved tenofovir disoproxil fumarate (TDF) and emtricitabine (FTC) for PrEP in 2012, and the number of patients prescribed PrEP has risen from 8768 in 2012 to 77,120 in 2016 and 100,282 in 2017, the study noted. ART delivery also has increased during this time.

The study took into account improvements in viral suppression brought about by improved ART coverage when examining whether increasing PrEP prescription was associated with decreases in the rate of HIV diagnoses.

“The estimated impact of changes in viral suppression rates on new diagnoses was smaller than anticipated,” Smith told Contagion®. “This is probably because changes were smaller than the changes in PrEP coverage over this time period.”

Overall, HIV diagnosis rates decreased from 13.1/100,000 people during 2012 to 11.8/100,000 during 2016 while average PrEP coverage increased from 0.7 per 100 in 2012 to 5.8 per 100 in 2016.

HIV diagnosis rates and PrEP coverage varied widely with EAPCs from 2012 to 2016 ranging from 14.4% in the District of Columbia to 4.3% in Nevada and PrEP coverage increases ranging from 16.0 per 100 in New York to 1.5 per 100 in Wyoming.

Investigators divided the states into quintiles based on their level of change in PrEP coverage during the study years. They found that states with the greatest increase in PrEP coverage also saw the greatest average decrease in HIV diagnosis rates while the states with the lowest increase in PrEP coverage saw no change in HIV diagnosis rates.

“Our next step is to analyze county-level data to determine if stronger associations concentrated among smaller populations were likely obscured by these analyses of data diffused across relatively large state populations,” Smith told Contagion®. “Additionally, continued efforts to monitor where and to whom PrEP is being effectively delivered and research to identify the most effective ways to increase access to PrEP among all people at substantial risk for HIV acquisition will speed efforts to reduce new HIV infections.”

PrEP is a key pillar in the global fight against HIV. A recent CDC report looked at the implementation of PrEP among countries supported by the US President’s Emergency Plan for AIDS Relief (PEPFAR). It found that by September 2018, only 15 of the PEPFAR supported countries had PrEP programs, but the client volume among them had increased by 3351% from October 2016 through September 2018.

Colleen Kelley, MD, MPH, associate professor at the Emory University School of Medicine, recently discussed barriers to PrEP in an interview with Contagion®, noting that implementation, access and persistence on PrEP remain challenges.