Patenting Strategies on Inhaler Delivery Devices

Patients with asthma and COPD rely on inhalers to control symptoms. Yet, these products remain expensive, in part because brand-name manufacturers have obtained numerous patents on inhalers, including on their delivery devices. Recent antitrust litigation has raised questions about the boundaries of listing device patents with the US Food and Drug Administration (FDA), particularly when patents do not claim any active ingredients.

How have manufacturers relied on device patents to preserve market exclusivity on brand-name inhalers?

We identified patents on brand-name inhalers approved for asthma and COPD between 1986 and 2020 using the FDA's Approved Drug Products with Therapeutic Equivalence Evaluations (Orange Book). We extracted information about patents from LexisNexis TotalPatent One and Google Patents and searched device patents for mention of active ingredients or other prespecified features linking the patent to the relevant drug. For each inhaler, we determined the duration of protection added by device patents.

The FDA approved 53 brand-name inhalers for asthma and COPD from 1986 through 2020, 39 of which had at least one device patent. One hundred thirty-seven distinct device patents were in the final cohort, representing 49% of all patents listed on inhalers. Seventy-seven percent of device patents made no mention of active ingredients or their molecular structures, and 72% made no mention of any relevant prespecified feature connecting the device patent to the drug product. For the 39 brand-name inhalers with one or more device patents listed in the Orange Book, device patents extended the duration of market protection by a median of 5.5 years (interquartile range, 0.0-10.5 years) beyond the last-to-expire nondevice patent.

Patent and regulatory reform is needed to promote generic competition and to ensure that patients with asthma and COPD have access to affordable medications.