Abstract 285: Association Of Patient Out-of-pocket Costs And Financial Assistance With Prescription Abandonment: The Case Of PCSK9 Inhibitors

Abstract

Background: Specialty drugs are typically subject to high out-of-pocket (OOP) costs, especially for Medicare Part D patients and commercially insured patients facing high deductibles and/or coinsurance. Financial assistance offered by charities or manufacturers often helps reduce OOP burden. Studies in several disease areas have shown that high OOP costs are associated with prescription abandonment, defined as failure to purchase an insurer-approved prescription at the pharmacy. We examined how OOP costs and financial assistance were associated with abandonment of PCSK9i prescriptions. Methods: This retrospective study utilized 2015-2017 claims data from Decision Resources Group for Medicare and commercially insured patients. We defined PCSK9i abandonment rate as the percentage of patients with no evidence of a dispensed PCSK9i in the 90 days after their first PCSK9i prescription was approved by the insurer. Logistic regressions controlling for demographic, clinical, and treatment characteristics were used to estimate risk-adjusted rates of abandonment across different OOP cost levels. We conducted simulations to predict abandonment rates if a patient’s OOP cost level changed and/or they did not receive financial assistance, while holding all other covariates constant. Analyses were conducted separately in the Medicare and commercially insured patients. Result: Our final sample included 8,024 Medicare beneficiaries and 3,865 commercially-insured patients. We found that higher OOP cost was associated with higher risk-adjusted PCSK9i abandonment rates in both groups. For instance, Medicare beneficiaries with $0 OOP cost had a 7.4% risk-adjusted abandonment rate, compared to 9.8% for the $1-$9 group (odds ratio [OR]:1.37; 95% CI:1.04-1.81), 19.6% for the $10-$99 group (OR: 3.12; 95% CI: 2.62-3.72), 42.6% for the $100-$199 group (OR: 9.99; 95% CI: 7.60-13.14), 51.9% for the $200-$299 group (OR: 14.48; 95% CI: 11.14-19.76), 58.5% for $300-$399 group (OR: 19.7; 95% CI: 15.01-25.86), and 59% for the ≥$400 group (OR: 20.13; 95% CI: 14.96-27.09). All comparisons were significant at P<0.05. About 4% of Medicare beneficiaries (n=288) and 32% of commercially insured patients (n=1,243) received financial assistance. Without it, their mean OOP costs would have increased from $31 to $386 for Medicare and $7 to $534 for commercial insurance and abandonment rates would have increased from 9.7% to 46.4% (change: 36.7% [95% CI: 31.4% -41.9%]) for Medicare and 4.4% to 27.4% (change: 23% [95% CI: 19.1% -26.9%] for commercial insurance. Conclusions: Higher OOP costs were associated with higher rates of PCSK9i abandonment. Lack of financial assistance was associated with increased abandonment. Our findings help inform current policy efforts to protect patients from high cost sharing, such as current bills in Congress aiming to reduce patient OOP burden under Medicare Part D.