Research Program Manager Johns Hopkins Bloomberg School of Public Health Baltimore, United States
Background: Approximately half of drug discounts originate from pharmacy-pharmacy benefits manager (PBM) programs rather than drug manufacturers, yet little is known regarding the use and impact of these programs.
Objectives: To characterize products using pharmacy-PBM discounts and to estimate the association between such discounts, prescription utilization and out-of-pocket costs.
Methods: Retrospective cohort study using IQVIA’s Formulary Impact Analyzer, which contains anonymized, individual-level pharmacy claims representing U.S. retail pharmacy transactions. We focused on 20 products with the greatest number of transactions using a pharmacy-PBM discount. Our unit of analysis was a treatment episode, defined as the length of time from an incident fill to no continuous use for 60 consecutive days after allowing for indefinite stockpiling. Main outcome measures included products with greatest pharmacy-PBM discount use, characteristics of treatment episodes with and without pharmacy-PBM discount, and patient out-of-pocket costs with and without pharmacy-PBM discount.
Results: Across all products, 2.0 of 53.5 million transactions (3.82%) were accompanied by a pharmacy-PBM discount; at a treatment episode level, 269,243 of 3,499,675 treatment episodes (7.69%) were accompanied by such discounts. Commonly discounted products included generic treatments for chronic disease (e.g., lisinopril, levothyroxine, metformin) and neuropsychiatric (alprazolam, amphetamine, buprenorphine, hydrocodone) conditions. Across all treatment episodes, the median post-discount out-of-pocket cost was more than 2.5-fold higher during treatment episodes with a discount compared to those without ($15.15, interquartile range [IQR] $8.53-32.00 vs. $5.88, IQR $1.40-15.00). The median treatment episode duration was 249 days (IQR 132-418) with discount use compared to 236 days (IQR 121-396) without discount use, although treatment episodes that began with a discount had fewer transactions per treatment episode and were shorter (median 212 days, IQR 114-360) than those that did not (313 days, IQR 178-500).
Conclusions: Pharmacy-PBM discounts may foster market competition and improve access for under- and uninsured individuals, however, these programs may not generate savings for many insured individuals.
