Patient liability, treatment adherence, and treatment persistence associated with state bans of copay accumulator adjustment programs.

Background: Health insurers have increased the use of copay accumulator adjustment programs (CAAPs) to control costs; however, some states within the United States have banned the use of CAAPs to protect patients from rising out-of-pocket expenses.
Objective: To assess the impact of state CAAP bans on patient liability, treatment adherence, and treatment persistence.
Methods: This was a retrospective cohort study using administrative claims recorded in the IQVIA PharMetrics Plus database. Data were extracted for patients with fully insured commercial plans receiving autoimmune or multiple sclerosis drugs between January 1, 2017, and December 31, 2021. Patient liability was defined as the difference in insurer allowed and paid amounts. Treatment adherence was measured as the proportion of days covered over a 1-year period, with "adherent" defined as a proportion of days covered greater than or equal to 80%. Treatment persistence was defined as time from treatment initiation to discontinuation (a period of 60 days without supply of treatment). The analysis compared differences in outcomes in states that implemented a CAAP ban during the study period (Arizona, Georgia, Illinois, Virginia, West Virginia) with states that did not, for before and after the date of ban.
Results: States that implemented a CAAP ban had relative reductions in patient liability after the first 2 months, which ranged from 41% to 63%, with monthly savings ranging from $128 to $520. Patients in states with a CAAP ban had 14% greater odds of being adherent to their treatment after policy implementation than patients in states without a CAAP ban and a 13% reduction in risk of discontinuing.
Conclusions: The implementation of state legislation to restrict the use of CAAPs in state-regulated plans was associated with reductions in patient liability and improvements in treatment adherence and persistence for the 5 states that were early implementers of a CAAP ban. These results may offer insights for states that have recently implemented a CAAP ban, as well as for those considering enacting similar legislation.