Patterns of Manufacturer Coupon Use for Prescription Drugs in the US, 2017-2019.

Importance: Although manufacturer-sponsored coupons are commonly used, little is known about how patients use them within a treatment episode. Objectives: To examine when and how frequently patients use manufacturer coupons during a treatment episode for a chronic condition, and to characterize factors associated with more frequent use. Design, Setting, and Participants: This is a retrospective cohort study of a 5% nationally representative sample of anonymized longitudinal retail pharmacy claims data from October 1, 2017, to September 30, 2019, obtained from IQVIA's Formulary Impact Analyzer. The data were analyzed from September to December 2022. Patients with new treatment episodes using at least 1 manufacturer coupon over a 12-month period were identified. This study focused on patients with 3 or more fills for a given drug and characterized the association of the outcomes of interest with patient, drug, and drug class characteristics. Main Outcomes and Measures: The primary outcomes were (1) the frequency of coupon use, measured as the proportion of prescription fills accompanied by manufacturer coupon within the treatment episode, and (2) the timing of first coupon use relative to the first prescription fill within the treatment episode. Results: A total of 36 951 treatment episodes accounted for 238 474 drug claims and 35 352 unique patients (mean [SD] age, 48.1 [18.2] years; 17 676 women [50.0%]). Among these episodes, nearly all instances (35 103 episodes [95.0%]) of first coupon use occurred within the first 4 prescription fills. Approximately two-thirds of treatment episodes (24 351 episodes [65.9%]) used a coupon for the incident fill. Coupons were used for a median (IQR) of 3 (2-6) fills. The median (IQR) proportion of fills with a coupon was 70.0% (33.3%-100.0%), and many patients discontinued the drug after the last coupon. After adjustment for covariates, there was no significant association between an individual's out-of-pocket costs or neighborhood-level income and the frequency of coupon use. The estimated proportion of fills with a coupon was greater for products in competitive (19.5% increase; 95% CI, 2.1%-36.9%) or oligopolistic (14.5% increase; 95% CI, 3.5%-25.6%) markets than monopoly markets when there is only 1 drug in the therapeutic class. Conclusions and Relevance: In this retrospective cohort analysis of individuals receiving pharmaceutical treatment for chronic diseases, the frequency of manufacturer-sponsored drug coupon use was associated with the degree of market competition, rather than patients' out-of-pocket costs.