Utilization and Spending With Preventive Drug Lists for Asthma Medications in High-Deductible Health Plans.

In this case-control study, reducing cost-sharing for asthma medications through a PDL was associated with increased adherence to controller medications, notably ICS-LABA medications used by patients with more severe asthma, but was not associated with improved clinical outcomes. These findings suggest that PDLs are a potential strategy to improve access and affordability of asthma care for patients in HDHP-HSAs.