Increasing patients’ out of pocket costs for HIV pre-exposure prophylaxis (PrEP), medications, which have been shown to dramatically reduce the risk of HIV infection, could lead to a significant reduction in PrEP use and a rise in HIV infection rates.
This is according to a study that appeared in Health Affairs, where the researchers used a large, proprietary database of medical and pharmacy claims to determine the rates at which patients failed to fill (i.e. abandoned) insurer-approved PrEP prescriptions at different levels of out-of-pocket costs.
Their findings suggest that even a small increase, from $0 to $10 in monthly PrEP out-of-pocket costs, would double the rate of PrEP prescription abandonment. Further, an increase in out-of-pocket costs to between $100 and $500 per month would result in nearly one-third of patients abandoning their PrEP prescriptions.
The analysis also highlighted the negative consequences of abandoning PrEP: The rate of new HIV infections in the year after the initial PrEP prescription was two to three times higher among those who never filled those prescriptions.
“Our findings suggest that out-of-pocket cost increases for PrEP could upend the progress that has been made towards ending the HIV/AIDS epidemic,” said study senior author Jalpa Doshi, PhD, a professor of Medicine and the director of Value-based Insurance Design Initiatives at the Center for Health Incentives and Behavioral Economics at Penn Medicine.
To date, the FDA has approved two HIV PrEP products, each of which combines two standard antiretroviral drugs in a single pill. For the past decade, the US Centers for Disease Control and Prevention (CDC) has recommended PrEP as a way of preventing HIV infection among higher-risk individuals.
The team reviewed a US-wide database covering insurer-provided health care, including prescription records, dating from 2016-2018. They analyzed this dataset to determine the rate of PrEP prescription abandonment — defined as a patient not picking up their newly-prescribed and insurer-approved PrEP prescription from the pharmacy within 365 days — at different out-of-pocket cost levels. Their analysis covered 58,529 patients with new, insurer-approved PrEP prescriptions, and adjusted for differences among the patients. Refills did not feature in the analysis.
They found that both the rate of PrEP prescription abandonment and the rate of delayed prescription fills increased as out-of-pocket costs rose. Also, patients who abandoned their PrEP prescription were two to three times more likely to get infected with HIV in the following year, compared to those who filled their PrEP prescription.
Based on their analyses, the researchers estimated that raising monthly patient out-of-pocket costs for PrEP from $0 to the $1-$10 category would nearly double the prescription abandonment rate (from 5.6 percent to 11.1 percent), while moving to the $101-$500 category the abandonment rate would be 34.7%. At the $500+ category, they estimated, the abandonment rate would be about 42.6%, nearly eight times the rate at the $0 level.
Overall, the results suggest that even a modest increase in patient out-of-pocket costs for PrEP could result in a sharp increase in prescription abandonment—and a subsequent large increase in the rate of new HIV infections.
The study was co-led by Lorraine Dean, ScD, Associate Professor at the Johns Hopkins Bloomberg School of Public Health.
