A brand-name drug is often protected by multiple patents, typically a patent to cover the active ingredient and patents to cover different uses of the drug. For a single-indication drug, generic drug makers are barred from manufacturing generic versions until both the active ingredient and drug use patents expire. However, when there are multiple drug use patents that expire at different times, section VIII of the United States’ 1984 Hatch-Waxman Act allows generic makers to seek approval for uses whose patents have expired1. In effect, the generic drug goes onto the market more quickly than otherwise, but it can only be used for unprotected indications. The generic drug is said to have a ‘skinny label’. Similar provisions exist in other countries, including EU countries and the UK.
Skinny labels often cause disputes between branded and generic drug makers. These disputes tend to revolve around how the generic drug maker promotes its drug.
In 2020, Amarin Pharma filed a lawsuit alleging that generic drug maker Hikma promoted off-label uses of generic icosapent ethyl2. Amarin is the producer of the branded drug Vascepa, patent-protected for two indications: treating severe hypertriglyceridemia (SH) and reducing cardiovascular risk (CV). When the patent for the SH indication expired in 2020, Hikma obtained a skinny label for its generic version that included only the SH indication. However, according to Amarin, Hikma had actively encouraged physicians to prescribe generic isocopent ethyl for off-label CV indications. Hikma denied this allegation.
In 2024, the Delaware court sided with Amarin, pointing to Hikma’s proclamation of its drug as the generic version of Vascepa without acknowledging the labelling limitations. In 2025, Hikma ordered an appeal against this decision, arguing that the decision exposes every generic drug manufacturer to substantial commercial damages. The U.S. Supreme Court has agreed to review the case in late Jan 2026; the outcome is to be awaited.
In 2014, a similar feud happened between GSK and generic maker Teva – both large players in their respective markets3. The Delaware court, again, sided with the branded drug maker in 2017. Teva filed a review order, which the Supreme Court refused to hear. The case ended in 2023, costing the generic manufacturer $235M in damages to GSK.
The cases around skinny label disputes serve as reminders that apply to any drug manufacturers: have a good knowledge of intellectual property (IP) laws and be careful when designing marketing materials. For aspiring biotechnology entrepreneurs, this highlights the importance of getting relevant education on the IP laws of the country where they operate.
Having a strong understanding of IP laws means companies are aware of their rights and duties, therefore avoiding unfair exploitation from competitors and costly lawsuits. Branded drug makers could have been ignorant and taken no action when a generic maker shows signs of patent rights violation, potentially costing the former valuable sales. Similarly, the generic maker could also be ignorant and produce marketing materials insensitive to their duties as a skinny-label holder. Even a small wording misstep could cost millions in legal damages.