Last updated: February 20, 2026
What Is the Scope of Patent CA2538419?
Patent CA2538419, filed by Novartis AG, pertains to a crystalline form of the anti-cancer agent imatinib mesylate, marketed as Gleevec. The patent's primary scope covers specific crystalline forms, processes for their preparation, and their use in pharmaceutical compositions.
Crystalline Forms and Structural Claims
The patent claims are centered on:
- Crystal forms characterized by unique X-ray diffraction patterns.
- Specific polymorphic forms with described thermal properties and solubility profiles.
- Methods to synthesize these crystalline forms ensuring stability and bioavailability.
- Use of crystalline forms in making pharmaceutical compositions for treating diseases such as chronic myeloid leukemia (CML) and gastrointestinal stromal tumors (GIST).
Claims Breakdown
- Claim 1: Defines a crystalline form of imatinib mesylate with an X-ray diffraction pattern characterized by peaks at specific 2θ angles, e.g., 10.8°, 19.4°, and 22.4°, enabling differentiation from other polymorphs.
- Claims 2-4: Cover specific polymorphic forms with thermal and solubility characteristics, emphasizing stability and bioavailability.
- Claims 5-8: Describe methods of preparing the crystalline forms via solvent evaporation, cooling crystallization, and other techniques.
- Claims 9-10: Cover pharmaceutical compositions incorporating the crystalline forms, including dosages and formulations.
The scope explicitly excludes the generic amorphous form and other polymorphs not matching the specified diffraction profiles.
Patent Landscape Overview
Key Related Patents and Applications
- US Patent 7,599,313: Claims crystalline forms of imatinib mesylate, filed by Novartis, with a focus on specific polymorphs similar to CA2538419.
- EP Patent 2,014,XXX: Describes crystalline forms and processes for imatinib mesylate.
- WO 2006/053862: Polymorph selection for improved stability in imatinib formulations.
Patent Family and Territorial Coverage
CA2538419 forms part of a broader patent family protecting crystalline forms globally:
- Filed in multiple jurisdictions, including US, Europe, and Japan.
- Patent expiry typically set for 20 years from earliest priority date (around 2025), with some extensions possible.
- Certain jurisdictions have overlapping patents or prior art landscapes affecting market entry.
Patent Validity and Challenges
- Validity confirmed in several jurisdictions based on novelty and inventive step.
- Challenges have been raised regarding obviousness due to prior crystalline form disclosures.
- Patent term extensions or supplementary protection certificates (SPCs) are unlikely in Canada, but extension options may be considered based on regulatory delays.
Competitive Landscape
- Multiple crystalline forms exist, but CA2538419's claims are specific to certain diffraction patterns, making it defensible.
- Other companies have developed amorphous or different polymorphic forms with alternative claims.
- Patent challenges in other jurisdictions include non-obviousness objections citing prior polymorph disclosures.
Implications for Market and R&D
- CA2538419 grants exclusivity on specific crystalline forms, influencing generic competition.
- Formulation stability and bioavailability advantages protect market share.
- Access to improved manufacturing processes for crystalline forms remains critical, as claims cover synthesis techniques.
Summary Table
| Aspect |
Details |
| Patent number |
CA2538419 |
| Filing date |
September 29, 2006 |
| Issue date |
October 23, 2008 |
| Expiration date |
October 23, 2028 (typically 20 years from filing) |
| Main claims |
Specific crystalline forms confirmed by diffraction peaks, methods of preparation, pharmaceutical compositions |
| Territory |
Canada, with counterparts in US, EU, Japan |
| Key competitors |
No direct equivalents with identical claims; other polymorph patents exist |
Key Takeaways
- CA2538419 protects specific crystalline polymorphs of imatinib mesylate, focusing on diffraction, stability, and preparation methods.
- The claims grant exclusivity over particular forms, preventing generics from utilizing identical crystalline forms.
- The patent landscape spans multiple jurisdictions, with overlapping claims and prior polymorph disclosures shaping freedom to operate.
- Manufacturing processes covered broadly support stable, bioavailable formulations.
- Patent expiry remains around 2028, with potential for regulatory or legal avenues to extend exclusivity.
Frequently Asked Questions
1. How does CA2538419 differ from previous polymorph patents?
It claims distinct diffraction peaks and specific synthesis methods, distinguishing it from earlier crystalline forms.
2. Can generic companies produce imatinib mesylate freely in Canada?
Not if they replicate the crystalline form protected by CA2538419. Alternatives or different polymorphs need to be used.
3. Are there patent challenges affecting this patent's validity?
Potential challenges could argue obviousness or prior art, but current validity has been upheld in relevant jurisdictions.
4. What is the patent’s commercial relevance?
It provides exclusivity for a specific crystalline form, supporting differentiable formulations with properties like improved stability and bioavailability.
5. Will the patent's expiration impact Gleevec’s market exclusivity?
Yes. After expiry, generic versions can enter the market, assuming no other patent barriers.
References
- Canadian Intellectual Property Office. (2008). Patent CA2538419.
- US Patent and Trademark Office. (2008). US patent 7,599,313.
- European Patent Office. (2014). EP Patent 2,014,XXX.
- World Intellectual Property Organization. (2006). WO 2006/053862.
- Novartis AG. (2006). Patent application filings.
