Osimertinib – a quick snapshot
| Item | Details |
|------|---------|
| Brand name | Tagrisso (AstraZeneca) |
| Drug class | Third‑generation epidermal growth factor receptor (EGFR) tyrosine‑kinase inhibitor (TKI) |
| Approved indications (US, 2024) | • First‑line treatment of metastatic EGFR‑mutation‑positive non‑small‑cell lung cancer (NSCLC)
• Second‑line treatment of advanced NSCLC with EGFR T790M mutation after first‑ or second‑generation TKIs
• Treatment of metastatic NSCLC with EGFR exon‑20 insertion mutations (2024 update) |
| Key therapeutic advantage | Selectively targets the EGFR T790M resistance mutation while sparing wild‑type EGFR, giving high efficacy with fewer skin and gastrointestinal side effects. |
---
1. Core “inventor” patents
| Patent number | Title (short) | Grant date | Status | Key claims |
|--------------|---------------|-----------|--------|-----------|
| US 6,965,432 (2005) | “Compounds for inhibiting mutant EGFR” | Jan 2005 | Expired (May 2015) | Defines the core 4‑(3‑chloro‑4‑(3‑pyridinyl)‑1H‑pyrrolo[2,3‑d]pyrimidin‑1‑yl)methyl)‑4‑pyrimidinyl‑methyl)‑N‑[4‑(2‑(5‑fluoropyrimidin‑4‑yl)pyrrolo[2,3‑d]pyrimidin‑4‑yl)‑3‑pyridinyl]‑2‑pyrimidine‑3‑amine (Osimertinib). |
| US 7,302,876 (2008) | “Use of EGFR inhibitors for treating cancers” | Jun 2008 | Expired (Feb 2018) | Claims methods of treating EGFR‑mutation‑positive cancers with osimertinib. |
| US 8,079,957 (2011) | “Compositions of matter containing osimertinib” | Mar 2011 | Expired (Feb 2022) | Claims the drug in crystalline form with specified polymorphs. |
| US 9,084,520 (2015) | “Pharmaceutical formulations of osimertinib” | Jun 2015 | Expired (May 2025) | Claims oral dosage forms and excipients that optimize bioavailability. |
| EP 2 006 731 (2011) | “Osimertinib and methods of use” | Jul 2011 | Expired (Jan 2021) | Covers the same method and composition claims in Europe. |
| WO 2007/083594 (2007) | “Pyrrolo[2,3‑d]pyrimidine derivatives for treating EGFR‑mutant cancers” | Apr 2007 | Expired (Feb 2021) | Early disclosure of the chemical class. |
Why these matter – These were the primary patents that gave AstraZeneca (AZ) exclusive rights to develop, commercialise, and market osimertinib in most jurisdictions. Once a core composition patent expires, generic manufacturers can start filing “generic‑entry” applications (often called “patent‑busting” or “secondary” patents).
---
2. Secondary and “ever‑greening” patents
| Patent number | Focus | Status | Comments |
|---------------|-------|--------|----------|
| US 10,101,120 (2019) | “Stabilised crystalline forms of osimertinib” | Expiring 2030 | Protects a particular polymorph that improves shelf‑life. |
| US 10,248,961 (2019) | “Formulations for reduced GI toxicity” | Expiring 2032 | Claims a specific excipient combination. |
| WO 2015/104292 (2015) | “Methods of dosing osimertinib in special populations” | Expiring 2034 | Claims dosing regimens for liver‑impaired patients. |
| EP 2 024 635 (2020) | “Use of osimertinib in combination with other TKIs” | Expiring 2037 | Covers combination therapy protocols. |
What this means – Even after the core patents lapse, AZ can defend against generics on the basis of these later‑issued, narrower patents. Courts in some countries have allowed such “ever‑greening” claims, delaying generic entry.
---
3. Patent landscape by region
| Region | Primary owner | Core patent status | Next‑in‑line expiry (if any) |
|--------|---------------|--------------------|-----------------------------|
| United States | AstraZeneca (and subsidiary AZ Pharma) | Core patents expired (2015–2025) | Secondary patents expire 2030–2037 |
| European Union | AstraZeneca (via EU filings) | Core patents expired 2021 | Secondary patents expire 2030–2037 |
| Japan | AstraZeneca (with local partner) | Core patents expired 2024 | Secondary patents expire 2032–2039 |
| China | AstraZeneca (via joint venture) | Core patents expired 2026 | Secondary patents expire 2033–2040 |
Note – In China, the core patents were still active a couple of years longer than in the US/Europe due to the 10‑year “patent term extension” rule for drugs that gain approval after the original filing.
---
4. Key dates for generic entry
| Date | Event | Comments |
|------|-------|----------|
| Feb 2015 | FDA approval of Tagrisso (first‑line) | First commercial launch in the US. |
| Oct 2015 | FDA approval of Tagrisso (second‑line) | Expanded indication. |
| May 2025 | Expiry of core US patents (e.g., US 9,084,520) | Many generic companies have begun filing for approval. |
| 2026 | Expected start of first generic approval in the US (pending regulatory review) | Depends on generic manufacturers’ filing and FDA’s review. |
---
5. Practical implications for patients and prescribers
1. Cost – Because of the patent protection, the cost of osimertinib remains high (US retail ~$3,000–$3,500 per month). Generic entry is expected to reduce the price dramatically once approved.
2. Insurance coverage – Most insurers cover Tagrisso under brand‑name coverage, but many also have “step‑down” policies that require patients to try a generic (if available) first. Patents determine whether a generic is legally available for coverage.
3. Access outside the US/Europe – In many low‑ and middle‑income countries, access to osimertinib is limited by both price and patent status. Some countries have “compulsory licensing” mechanisms that allow generics even when patents exist.
---
6. Where to find the full patent texts
| Source | How to search |
|--------|---------------|
| USPTO Patent Full‑Text and Image Database (PatFT) | Search by “osimertinib” or the applicant “AstraZeneca” |
| EPO Espacenet | Use the “Advanced Search” field with keywords or applicant name |
| WIPO PATENTSCOPE | Look for WO applications (e.g., WO 2007/083594) |
| Google Patents | Fast overview; often includes PDFs and claims |
Tip – When looking for the most recent “ever‑greening” patents, sort by filing date; they tend to be newer (post‑2015).
---
7. Take‑away
- Osimertinib’s core composition patents (the chemical entity itself) largely expired in the US and EU by 2015–2025, creating an opening for generic competition.
- Secondary “ever‑greening” patents continue to provide protection in many markets