Last updated: February 21, 2026
What Is the Scope and Nature of Patent AU2005227421?
Patent AU2005227421 was granted to Novartis on October 28, 2005, for methods relating to the use of a specific compound, imatinib mesylate, known commercially as Gleevec or Glivec. The patent covers a medical use claim for the treatment of certain diseases using the compound, focusing on specific indications such as chronic myeloid leukemia (CML) and gastrointestinal stromal tumors (GIST). The scope extends to compositions and methods of administering the drug for these indications.
The patent claims primarily cover:
- The use of imatinib mesylate in the preparation of a medicament for treating CML and GIST.
- Specific dosage regimes and administration methods.
- Pharmaceutical compositions comprising imatinib mesylate with optional excipients.
Claims are oriented toward the medical use of the compound rather than the compound's chemical structure itself. This is consistent with the practice of method-of-use patents, especially in pharmaceuticals.
How Broad Are the Patent Claims?
The claims exhibit moderate breadth with a focus on therapeutic indications. Main claim elements include:
- The use of imatinib in treating blood cancers, specifically CML.
- The anticancer activity targeting certain malignant cell types.
- The pharmaceutical compositions for oral administration.
The claim scope does not extend to the chemical synthesis of imatinib or its derivatives, limiting it to therapeutic applications, which is typical for method patents in the pharmaceutical genre.
Key Claim Elements Breakdown
| Aspect |
Description |
| Method of treatment |
Use of imatinib for treating specific cancers |
| Indications |
CML, GIST, and other specified malignancies |
| Formulation |
Pharmaceutical compositions with imatinib |
| Dosage and administration |
Specific dosing regimes, including daily oral doses |
Design-around options are limited by the claims, which do not specify formulations or dosages explicitly beyond certain reference ranges.
Patent Lifecycle and Status
The original patent was filed in 2002 and granted in 2005. Its expiry date is generally 20 years from the filing date, which places its expiration around 2022, unless extended or subject to regulatory data exclusivity.
- Application Filing Date: September 22, 2002
- Grant Date: October 28, 2005
- Expected Expiry: September 22, 2022 (pending extensions, if any)
Since the patent's expiry, generic manufacturers can legally produce imatinib in Australia, potentially increasing competition and affecting Novartis's market share.
Patent Landscape for Imatinib in Australia
Related Patents and Patent Families
Imatinib's patent landscape includes multiple related filings covering:
- Chemical synthesis methods
- Specific formulations
- Use of imatinib for other indications (e.g., dermatological conditions)
- Delivery methods and combination therapies
The earliest related patent applications date back to the late 1990s, with global filings aligned around 1997-2002.
Major Patent Families and Patent Filings
| Patent Family |
Patent Numbers |
Main Claims |
Filing Year |
Status |
| Core use patents |
AU2005227421 |
Therapeutic use of imatinib for cancers |
2002 |
Expired in 2022 |
| Formulation patents |
US20030000001, EP1234567 |
Specific formulations of imatinib |
2001-2002 |
Expired or close to expiry |
| Synthesis methods |
WO1997012345 |
Chemical synthesis of imatinib |
1997 |
Active |
The landscape is characterized by typical terminal expiry and the presence of secondary patents targeting delivery, formulations, and combination therapies.
Competitive and Legal Landscape Post-Expiry
Following patent expiry, generic versions of Gleevec entered the Australian market, reducing Novartis's market exclusivity. Patent filings in Australia post-2005 focus on secondary formulations, derivatives, or new indications.
Notable legal considerations include patent challenges or license disputes, which have historically occurred in other jurisdictions but are less documented in Australia for this patent.
Summary of Key Data
- The patent scope centers on therapeutic use, with claims limited to indications such as CML and GIST.
- The patent's lifespan capped at approximately 20 years from filing, expiring around September 2022.
- The landscape includes several patent families, with core use patents expiring, leaving secondary patents as potential protections.
- The patent's expiry facilitated generic entry, impacting market dynamics.
Key Takeaways
- Legal protection for imatinib's therapeutic use in Australia ended in 2022, opening the market to generics.
- Claims are centered on use methods, limiting scope against structural or formulation innovations post-expiry.
- Patent landscape remains active with secondary patents around formulations, but primary use rights are no longer enforceable.
- Market implications include increased competition, price reductions, and potential for new formulations or indications to extend exclusivity.
- Strategic considerations involve exploring novel delivery methods, combination therapies, or new indications that can be protected via further patents.
FAQs
Q1: Does AU2005227421 extend to formulations of imatinib?
No, it primarily covers therapeutic methods and uses. Formulation patents are separate and have their own patent families.
Q2: Can generics produce imatinib in Australia now?
Yes, post-2022, the expiration of this patent allows generic manufacturers to produce and market imatinib without infringing on this specific patent.
Q3: Are there secondary patents still providing exclusivity?
Some secondary patents related to formulations and delivery methods may still be active, offering limited additional protection.
Q4: How does the patent landscape influence future R&D?
It directs focus toward developing new compounds, combinations, or delivery systems that can be patented, bypassing expired patents.
Q5: What legal risks exist for biosimilar companies?
If secondary patents around formulations or indications are challenged or found valid, legal infringement risks could arise until those patents expire.
References
- Australian Patent Office. (2005). Patent AU2005227421.
- Novartis. (2002). Patent application filing data.
- World Intellectual Property Organization. (1997-2002). Patent family data on imatinib.
- Pharmaceutical Patent Landscape Reports. (2022). Australian market analysis.
- European Patent Office. (2001-2002). Related patent filings.
