Uptake in PrEP Could Plummet Prevalence of New HIV Infections

Preventing new HIV infections has been deemed a priority that is crucial for global health. HIV affects nearly all populations across the globe and has resulted in a cascade of health care costs related to adverse events and treatment.

A recent study published by the Journal of Acquired Immune Deficiency Syndromes suggests that if one-quarter of men who have sex with men (MSM) started pre-exposure prophylaxis (PrEP) with emtricitabine/tenofovir (Truvada), approximately 30% of new HIV cases would be mitigated.

In the study, the authors created a 10,000-person model of high-risk MSM to determine how varying levels of PrEP uptake would affect new diagnoses.

Significantly, if the model was implemented in the real-world, the United States would surpass the National HIV/AIDS Strategy—to reduce new infections 25% by 2020, according to the study.

The researchers investigated whether daily use of PrEP would affect transmission. They found that PrEP uptake in any percentage of high-risk patients would result in an increased rate of HIV prevention, according to the study.

“We know that PrEP is highly effective at preventing HIV infection, what we don’t know is how much of an impact it will have at the population level considering the numerous behavioral strategies that men use to prevent infection,” said researcher Michael T. LeVasseur, PhD. “This study attempts to answer this question and future work with this model will attempt to identify specific strategies that will work best to stop the transmission of HIV.”

The authors also examined the efficacy of other HIV prevention methods on their own or in combination. Specifically, they analyzed condom use, seroadaptive behaviors, and treatment as prevention.

Included in the analysis were data modeled after a 10,000-person population including urban, non-monogamous MSM at a high risk of contracting HIV. Approximately 19% of the overall population were HIV-positive, with 44% unaware or their status. Another 36% of HIV-negative patients were not tested for HIV within the previous year.

When PrEP was the only preventive therapy used by 1% of HIV-negative patients, 1.6% of infections were mitigated. Notably, when 25% of the HIV-negative population used PrEP, 30.7% of infections were prevented, according to the study.

Condom use as the only prevention method averted 48.8% of new HIV infections, while seroadaptive behaviors averted 37.7% of infections. Treatment as prevention was also observed to reduce new infections by 27.1%, according to the study.

The authors found that when all 3 prevention methods were combined, 72.2% of new infections were inhibited.

“PrEP is just another ‘tool in the toolbox’ for HIV prevention, but it is an important one,” Dr LeVasseur said. “PrEP can empower individuals who are in relationships where one person has HIV and the other doesn’t. It can also ease anxieties around HIV testing, as well as enhance sexual intimacy.”

However, the researchers noted that PrEP use among high-risk individuals is low.

“It’s probably low because of a lack of knowledge among patients, as well as providers, coupled with high costs,” LeVasseur said.

Additionally, high costs may be a concern for patient adherence to PrEP, despite manufacturer discounts and insurer coverage, according to the authors.

These findings show that PrEP has the potential to decrease HIV cases and can increase testing for sexually transmitted infections, in addition to alleviating concerns among MSM, according to the study.

“Many men who have sex with men have felt significant anxiety around sexual intimacy due to fear of HIV infection, even with condom use, frequent HIV testing and seroadaptive techniques,” Dr LeVasseur said. “Highlighting how effective these prevention methods are would certainly lead to an increase in PrEP uptake and easing of the mind.”