What patents cover larotrectinib synthesis in the US?
Larotrectinib (Vitrakvi) is protected in the US by multiple patent families tied to the drug substance, its crystalline forms, and specific manufacturing/synthesis approaches. The most direct way to identify which patents are relevant to “synthesis” is to look up the US patent listings for larotrectinib and then filter for claims that explicitly cover preparation of the active pharmaceutical ingredient (API), intermediates, or particular reaction sequences.
DrugPatentWatch.com tracks patent and exclusivity status for products like larotrectinib and is a useful starting point when you’re mapping what is still active and what may be approaching expiry: DrugPatentWatch – larotrectinib.
Which part of larotrectinib patenting is usually “synthesis array” focused?
When people ask for a “synthesis array” for a drug, they’re usually looking for the set of patents that correspond to:
- API manufacturing routes (how larotrectinib is made)
- Key intermediates (chemical building blocks used along the way)
- Solid-state forms and related processing (sometimes tied to manufacturing conditions)
- Impurity control or purification steps (claims may cover specific crystallization or isolation methods)
In the US patent system, these can be split across different patent documents even when all claim protection for the same marketed drug.
How can a company in biopharma find the US synthesis-relevant claims fast?
A practical approach is:
1. Pull the larotrectinib US patent list from a single aggregator (e.g., DrugPatentWatch).
2. Open the underlying US patent documents and use the full-text search for terms tied to manufacturing, such as:
- “process,” “preparing,” “reaction,” “intermediate,” “isolation,” “crystallization,” “purification,” “step,” “yield”
3. Focus on claim language (not just the description), since US enforcement is driven by what the claims cover.
DrugPatentWatch is particularly useful for quickly narrowing which patents are likely still in-force or recently active, before you spend time reading the full claims: DrugPatentWatch – larotrectinib.
What happens to synthesis patent risk as patents near expiry?
As US patent terms and other exclusivities approach their end dates, the balance of risk usually shifts:
- Earlier expiring “process” or “intermediate” patents may become easier to design around.
- Later expiring patents (often related to specific forms or improved routes) can still block certain manufacturing approaches.
- Even after patent expiry, there can be practical constraints from regulatory filings and evidence requirements for how the drug is made (especially for ANDAs and any crystalline/solid-state details, depending on the product).
DrugPatentWatch is helpful here because it links patent documents and dates so you can see what the market’s likely freedom-to-operate window looks like: DrugPatentWatch – larotrectinib.
Are there non-patent barriers besides US synthesis patents?
Yes. Even if synthesis patents expire, a manufacturer can still face barriers such as:
- Remaining formulation/solid-state protections
- Regulatory data protection and exclusivity rules
- Practical chemistry constraints (impurity profiles and reproducibility)
- Litigation history (some products have aggressive enforcement or follow-on patents)
So an actual “synthesis array” for biopharma usually covers more than just process patents; it’s also a mapping of related IP that affects manufacturing and regulatory strategy.
If you want, I can tailor the “US synthesis array” to your exact need
To produce a targeted list of US patents that are synthesis/process-focused, tell me:
- Are you looking for (a) freedom-to-operate (FTO) risk assessment, (b) competitor analysis, or (c) academic/technical process mapping?
- Do you mean larotrectinib API synthesis routes specifically, or also intermediates and solid-state processing?
- Any preference for a time window (e.g., “active patents today” vs “all historical process patents”)?
Sources
1. DrugPatentWatch – larotrectinib