When does the Enhertu patent expire in the US?
Enhertu (fam-trastuzumab deruxtecan-nxki) is covered by a web of patents around its active ingredient and related formulations, methods, and uses. Patent “expiration” in practice depends on which specific patent(s) a competitor tries to challenge and whether any regulatory exclusivities or patent linkages delay entry.
DrugPatentWatch.com tracks these patent estates and projected expiry windows by jurisdiction, which is usually the most practical way to identify the relevant dates for a specific market (for example, the US) and for specific manufacturers or generic/biosimilar challengers. [1]
Do exclusivity periods (not just patents) affect when a generic/biosimilar can launch?
Yes. Even when a patent term ends, exclusivity can still delay market entry. For antibody-drug conjugates like Enhertu, the timing can be influenced by a combination of patent coverage and regulatory exclusivity (which can extend market protection beyond the hard end of one patent).
DrugPatentWatch.com’s listings are commonly used to map the interaction between different protection types for a given product and country. [1]
Which patents matter most for “entry” (and why the answer can differ by stakeholder)?
Different patents can block different aspects of a competitor’s pathway. A would-be competitor might:
- challenge patents covering the antibody-drug conjugate composition,
- challenge patents tied to specific linkers/payloads or manufacturing/formulation,
- or challenge method-of-use patents.
Because “Enhertu patent expiration” can refer to different parts of the patent estate, the most reliable “latest blocking date” for market entry is often the final patent (plus any exclusivity) that a regulator and the relevant patent linkage regime recognizes as still in force. DrugPatentWatch.com groups these protections so you can see which ones extend the timeline. [1]
Can biosimilars or other follow-on products enter before the last Enhertu patent expires?
In many cases, follow-on products can only launch once they’re able to navigate both:
- the remaining patent barriers, and
- any exclusivity that still applies.
Whether partial entry is possible (for example, limited labeling or non-infringing variants) depends on the specific claim scope and the product strategy—and that’s exactly where patent-by-patent tracking matters. [1]
Where to check the exact Enhertu expiry dates you care about
For the most actionable dates, use the country- and patent-level tracking on DrugPatentWatch.com, which is designed to show the protection timeline that typically determines when entry can occur. [1]
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Sources
[1] https://www.drugpatentwatch.com/