Out-of-Pocket and Health Care Spending Changes for Patients Using Orally Administered Anticancer Therapy After Adoption of State Parity Laws

Abstract

Importance: Oral anticancer medications are increasingly important but costly treatment options for patients with cancer. By early 2017, 43 states and Washington, DC, had passed laws to ensure patients with private insurance enrolled in fully insured health plans pay no more for anticancer medications administered by mouth than anticancer medications administered by infusion. Federal legislation regarding this issue is currently pending. Despite their rapid acceptance, the changes associated with state adoption of oral chemotherapy parity laws have not been described.

Objective: To estimate changes in oral anticancer medication use, out-of-pocket spending, and health plan spending associated with oral chemotherapy parity law adoption.

Design, setting, and participants: Analysis of administrative health plan claims data from 2008-2012 for 3 large nationwide insurers aggregated by the Health Care Cost Institute. Data analysis was first completed in 2015 and updated in 2017. The study population included 63 780 adults living in 1 of 16 states that passed parity laws during the study period and who received anticancer drug treatment for which orally administered treatment options were available. Study analysis used a difference-in-differences approach.

Exposures: Time period before and after adoption of state parity laws, controlling for whether the patient was enrolled in a plan subject to parity (fully insured) or not (self-funded, exempt via the Employee Retirement Income Security Act).

Main outcomes and measures: Oral anticancer medication use, out-of-pocket spending, and total health care spending.

Results: Of the 63 780 adults aged 18 through 64 years, 51.4% participated in fully insured plans and 48.6% in self-funded plans (57.2% were women; 76.8% were aged 45 to 64 years). The use of oral anticancer medication treatment as a proportion of all anticancer treatment increased from 18% to 22% (adjusted difference-in-differences risk ratio [aDDRR], 1.04; 95% CI, 0.96-1.13; P = .34) comparing months before vs after parity. In plans subject to parity laws, the proportion of prescription fills for orally administered therapy without copayment increased from 15.0% to 53.0%, more than double the increase (12.3%-18.0%) in plans not subject to parity (P < .001). The proportion of patients with out-of-pocket spending of more than $100 per month increased from 8.4% to 11.1% compared with a slight decline from 12.0% to 11.7% in plans not subject to parity (P = .004). In plans subject to parity laws, estimated monthly out-of-pocket spending decreased by $19.44 at the 25th percentile, by $32.13 at the 50th percentile, and by $10.83 at the 75th percentile but increased at the 90th ($37.19) and 95th ($143.25) percentiles after parity (all P < .001, controlling for changes in plans not subject to parity). Parity laws did not increase 6-month total spending for users of any anticancer therapy or for users of oral anticancer therapy alone.

Conclusions and relevance: While oral chemotherapy parity laws modestly improved financial protection for many patients without increasing total health care spending, these laws alone may be insufficient to ensure that patients are protected from high out-of-pocket medication costs.

Figure 1.. Association of Parity Laws With Monthly Out-of-Pocket Spending for Orally Administered Anticancer Medications

Data represent quantile regression analyses of Health Care Cost Institute claims, 2008-2012 (85 107 observations), in propensity-weighted cohorts to estimate changes in the distribution of patient out-of-pocket spending on a single prescription fill of orally administered anticancer therapy. Medication costs per prescription fill were adjusted to reflect a standardized dosage of therapy, and dollars were inflation adjusted to 2012 US dollars by using the medical component of the US Consumer Price Index. Models were estimated using PROC QUANTREG in SAS, version 9.4 (SAS Institute Inc). Values in parentheses represent baseline spending per prescription fill for each percentile; data markers show the mean change in spending after parity at the specified point on the distribution; error bars, 95% CIs.

Figure 2.. Association of Parity Laws With 6-Month Total Health Care Spending

Data represent an analysis of Health Care Cost Institute claims, 2008-2012. Propensity score–weighted, generalized estimating equations with logarithmic links and gamma distributions were used to estimate 6-month spending on health care services. Models were estimated using PROC GENMOD in SAS, version 9.4 (SAS Institute Inc). There were no significant differences in total health care spending as a result of parity laws adoption for all anticancer medication users (adjusted difference-in-differences risk ratio [aDDRR], 0.96; 95% CI, 0.90-1.02; P = .09) or for orally administered anticancer medication users (aDDRR, 1.06; 95% CI, 0.93-1.20; P = .40).