Patent Litigation and the Timing of Entry by Biologic Biosimilars Compared to Small Molecule Generics in the US,...

In the US, the trade-off between incentivizing innovation and providing affordable medicines is managed by government regulation. New medicines are provided a lucrative period of exclusivity that is followed by competitive entry and lower prices. For small-molecule drugs, generic competition is now common, whereas for most biologics, biosimilars are unavailable, and the regulations governing competition are relatively new.

The authors compared the nominal patent term (time between originator/brand entry and the latest patent expiration date) and effective market life (time between originator/brand entry and biosimilar/generic entry) of the 15 biologics and 141 small molecules experiencing competitive entry during 2015-25. They also examined how litigation outcomes affected these outcomes.

Despite having a much longer nominal patent term, the effective market life of biologics was similar to small-molecule drugs in recent years. Biosimilars were more likely to be launched during active patent litigation, whereas generics were more likely to be launched after settlements.

Although biosimilars are still relatively rare, the patent litigation structure does not appear to be slowing competitive entry for biologics relative to small-molecule drugs. Biosimilar competition may become more common as biologics advance in their life cycle and regulations are brought to bear.