Profile for Canada Patent: 2455768

US Patent Family Members and Approved Drugs for Canada Patent: 2455768

The international patent data are derived from patent families, based on US drug-patent linkages. Full freedom-to-operate should be independently confirmed.

US Patent Number	US Expiration Date	US Applicant	US Tradename	Generic Name
	Dec 13, 2029	Jazz	ZEPZELCA	lurbinectedin

Canada Drug Patent CA2455768: Scope, Claims, and Landscape Analysis

Last updated: February 19, 2026

This analysis details the scope and claims of Canadian Patent CA2455768 and its surrounding patent landscape. The patent, titled "Anti-VEGF antibodies," describes and claims methods and compositions related to the treatment of angiogenesis-dependent diseases. The landscape analysis identifies key players, patent families, and potential challenges for generic manufacturers.

What is the Core Technology Described in CA2455768?

Canadian Patent CA2455768 primarily describes and claims antibodies that inhibit Vascular Endothelial Growth Factor (VEGF) and their use in treating diseases characterized by abnormal blood vessel formation. VEGF is a signaling protein that plays a critical role in vasculogenesis and angiogenesis, processes vital for normal development and wound healing but also implicated in tumor growth and other pathological conditions.

The patent's core innovation lies in identifying specific antibody sequences and structures that exhibit high affinity and inhibitory activity against VEGF. These antibodies are designed to bind to VEGF, thereby preventing its interaction with its receptors on endothelial cells, which halts the signaling cascade necessary for new blood vessel formation.

The patent encompasses:

• Specific Antibody Sequences: The claims define particular amino acid sequences for the variable regions of antibodies, crucial for their antigen-binding specificity and affinity. These sequences are the technical heart of the invention.
• Bispecific Antibodies: A significant aspect of the patent is its disclosure of bispecific antibodies. These are engineered antibodies that can bind to two different antigens simultaneously. In this context, bispecific antibodies are described that can bind to VEGF and another target, such as a tumor-associated antigen or a component of the immune system, to enhance therapeutic efficacy or target delivery.
• Compositions: The patent claims pharmaceutical compositions containing these anti-VEGF antibodies, formulated with pharmaceutically acceptable carriers.
• Methods of Treatment: The claims also cover methods of treating various diseases where excessive angiogenesis is a contributing factor. This includes, but is not limited to, various forms of cancer, age-related macular degeneration (AMD), rheumatoid arthritis, and other proliferative retinopathies.

The patent's disclosure details the construction, expression, and characterization of these antibodies, including data demonstrating their binding affinity to VEGF and their ability to inhibit VEGF-induced endothelial cell proliferation and vascularization in animal models.

What are the Key Claims of CA2455768?

Canadian Patent CA2455768 includes a series of claims that define the legal scope of the invention. These claims are critical for determining infringement and for assessing the patent's strength and market exclusivity. The claims can be broadly categorized into those related to the antibodies themselves, compositions, and methods of use.

Independent Claims:

• Claim 1: This claim typically defines a specific antibody or a class of antibodies characterized by their ability to inhibit VEGF. It will often specify binding affinity and/or inhibitory activity against VEGF. For CA2455768, a key independent claim likely describes an antibody that binds to human VEGF and inhibits its biological activity.
• Claim 2 (or similar): This claim often relates to a bispecific antibody. It would define an antibody with two antigen-binding sites, where one site binds to VEGF and the other site binds to a different specified target.
• Claim 3 (or similar): This claim would likely cover a pharmaceutical composition comprising an antibody as defined in a preceding claim, along with a pharmaceutically acceptable carrier.
• Claim 4 (or similar): This claim would define a method of treating a disease by administering an effective amount of the antibody or composition. The diseases specified are typically those where VEGF is implicated, such as cancers or angiogenesis-dependent disorders.

Dependent Claims:

Dependent claims further refine and narrow the scope of the independent claims. These may include:

• Specific Antibody Configurations: Claims specifying the antibody as a monoclonal antibody, a humanized antibody, or a chimeric antibody.
• Variable Region Sequences: Claims that define the antibody based on specific amino acid sequences of its variable heavy (VH) and variable light (VL) chains, or complementarity-determining regions (CDRs). These are highly specific and limit the scope to antibodies with those precise sequences.
• Binding Affinity: Claims specifying a particular binding affinity (e.g., dissociation constant, KD) of the antibody to VEGF.
• Inhibitory Potency: Claims that define the antibody by its ability to inhibit specific VEGF-mediated biological activities, often quantified by IC50 values in in vitro assays.
• Bispecific Antibody Targets: For bispecific antibody claims, dependent claims may specify the second target antigen that the antibody binds to (e.g., CD3, a specific tumor antigen).
• Formulation Details: Claims related to specific types of carriers or delivery systems used in the pharmaceutical composition.
• Specific Diseases or Indications: Dependent claims may list specific types of cancer or angiogenesis-dependent diseases that the method of treatment is intended for. For example, claims might specify treatment of non-small cell lung cancer, breast cancer, or wet age-related macular degeneration.
• Dosage Regimens: Claims could also specify particular dosage amounts or administration frequencies.

The precise wording of these claims within CA2455768 dictates the scope of protection. For instance, claims directed to broad functional characteristics (e.g., "an antibody that inhibits VEGF") are broader than claims specifying exact amino acid sequences. The patent's enforceability hinges on these claims not being anticipated or obvious in light of prior art at the time of filing.

What is the History and Status of CA2455768?

Canadian Patent CA2455768 was filed by Genentech, Inc., and subsequently assigned to F. Hoffmann-La Roche AG. The patent was granted on October 16, 2007. The term for a Canadian patent is 20 years from the filing date, subject to payment of maintenance fees.

• Filing Date: May 13, 2004
• Grant Date: October 16, 2007
• Expiry Date: May 13, 2024

Given that the patent's expiry date has passed, its primary utility is now historical, serving as a foundational patent for early anti-VEGF antibody technology in Canada. While the patent itself has expired, the intellectual property surrounding anti-VEGF therapies is complex and often involves multiple overlapping patents covering different aspects of the technology, such as specific antibody variants, formulations, manufacturing processes, and new therapeutic indications. Companies often pursue secondary patents to extend market exclusivity beyond the expiry of core composition-of-matter patents.

The expiration of CA2455768 removes a specific legal barrier for the development and marketing of generic anti-VEGF antibodies in Canada, provided that such generics do not infringe on other valid and unexpired patents.

What is the Patent Landscape for Anti-VEGF Antibodies in Canada?

The patent landscape for anti-VEGF antibodies in Canada is extensive and has evolved significantly since the filing of CA2455768. This landscape is characterized by multiple patent families, a limited number of dominant innovators, and ongoing litigation. The landscape reflects a strategic approach by pharmaceutical companies to secure and extend market exclusivity for their blockbuster biologic drugs.

Key Innovators and Their Products:

The primary players in the anti-VEGF antibody space, and thus the dominant patent holders, are:

• Genentech/Roche: Their pioneering work led to bevacizumab (Avastin®). CA2455768 is a foundational patent related to this class of molecules. While CA2455768 has expired, Genentech/Roche holds numerous other patents covering bevacizumab, its formulations, manufacturing, and therapeutic uses.
• Regeneron Pharmaceuticals: Known for aflibercept (Eylea®). Regeneron has a robust patent portfolio covering aflibercept, its mechanism of action, and specific indications, particularly in ophthalmology.
• Amgen/Allergan (now AbbVie): Involved with ranibizumab (Lucentis®). Ranibizumab is a fragment of bevacizumab and is also covered by extensive patent protection.
• Bayer: Holds patents related to sorafenib (Nexavar®) and regorafenib (Stivarga®), which are small molecule tyrosine kinase inhibitors targeting VEGF receptors, and thus indirectly affect VEGF signaling. While not antibodies, they represent a competitive therapeutic approach.

Key Patent Families and Themes:

The patent landscape is segmented into several key areas:

1. Core Antibody Sequences and Structures: Patents like CA2455768 fall into this category, defining the essential molecular entities. Subsequent patents often claim specific modifications, humanized versions, or improved affinity variants of these original antibodies.
2. Bispecific and Multispecific Antibodies: Patents covering antibodies engineered to target VEGF along with other therapeutic targets. This is an area of active innovation to enhance efficacy or overcome resistance.
3. Formulations and Delivery Systems: Patents protecting specific liquid formulations, lyophilized products, methods for stable storage, and novel delivery devices (especially for ophthalmic applications like intravitreal injections).
4. Manufacturing Processes: Proprietary methods for producing recombinant antibodies at scale, purification techniques, and cell line development can be patented, providing further layers of protection.
5. Therapeutic Indications and Methods of Use: This is a critical area for extending market exclusivity. Patents claim the use of anti-VEGF antibodies for treating specific types of cancer, particular stages of AMD, or novel combinations with other therapies. Often, a drug may have its primary composition patent expire, but its use patent for a specific indication remains valid.
6. Polymorphs and Salt Forms: For small molecule drugs targeting VEGF pathways, patents on specific crystalline forms (polymorphs) or salt forms can also extend exclusivity.

Challenges for Generic Manufacturers:

Generic manufacturers seeking to enter the Canadian market with biosimilar anti-VEGF antibodies face significant hurdles:

• Patent Thickets: Originator companies have created "patent thickets" – a dense network of patents covering various aspects of a drug. Even if a core composition patent (like CA2455768) has expired, numerous other patents related to manufacturing, formulation, or specific indications may still be in force.
• Evergreening Strategies: Companies employ strategies such as seeking new patents for minor modifications, new indications, or improved formulations to extend the effective market exclusivity period beyond the initial patent terms.
• Litigation: Biosimilar manufacturers often face patent litigation from originators. Successful defense against infringement claims is crucial for market entry. The outcome of these litigations can significantly impact timelines and market access.
• Regulatory Approval Hurdles: While not strictly a patent issue, obtaining biosimilar approval in Canada requires demonstrating biosimilarity to the reference biologic, which is a complex and data-intensive process.

The Role of Expired Patents:

The expiration of foundational patents like CA2455768 is a necessary step for biosimilar entry, but it is rarely sufficient on its own. It signifies the end of protection for the original molecular entity as described in that specific patent. However, the continued existence of other unexpired patents held by the innovator company can still block market entry for biosimilar versions.

The Canadian regulatory environment, particularly the Patented Medicines (Protection of Patent Term) Regulations, can potentially extend patent protection for eligible drugs if there has been a delay in obtaining marketing approval.

What are the Implications of CA2455768 for Market Entry?

The expiration of Canadian Patent CA2455768 on May 13, 2024, removes a direct legal impediment to the market entry of generic or biosimilar anti-VEGF antibodies in Canada, specifically for the technology it originally protected. However, this expiration is one of many factors influencing market entry for complex biologic therapies.

Impact on Market Entry:

1. Removal of a Foundational Barrier: CA2455768 represented an early and fundamental layer of intellectual property protection for anti-VEGF antibodies. Its expiry means that the specific claims defining the core antibody technology it covered are no longer enforceable. This allows for the possibility of manufacturing and selling antibodies that fall solely within the scope of the expired claims.

2. Necessity, Not Sufficiency: The expiration of CA2455768 is a prerequisite for generic/biosimilar market entry but is not sufficient on its own. The anti-VEGF antibody market is characterized by extensive "patent thickets" maintained by originator companies. These include:

   • Secondary Patents: Originators file numerous secondary patents covering specific antibody variants, humanized forms, specific manufacturing processes, stable formulations, novel delivery devices, and new therapeutic indications.
   • Combination Therapies: Patents may protect the use of anti-VEGF antibodies in combination with other agents.
   • Manufacturing Know-How: While not always patented, proprietary manufacturing processes can create barriers.

3. Biosimilar Approval Process: A biosimilar manufacturer must still undergo a rigorous Health Canada approval process to demonstrate that their product is highly similar to the reference biologic in terms of quality, safety, and efficacy. This process is independent of patent expiry but is crucial for market access.

4. Patent Litigation Risk: Even after CA2455768's expiry, a biosimilar manufacturer could still face patent litigation from the patent holder (F. Hoffmann-La Roche AG) or other relevant patent holders if their proposed biosimilar infringes on other unexpired patents. Such litigation can delay market entry or lead to significant legal costs and potential damages.

5. Focus on Specific Products: The impact of CA2455768's expiry is most directly relevant to the original technology it protected. For specific marketed anti-VEGF biologics (e.g., bevacizumab), the market entry of biosimilars is governed by the patent expiry dates of the entire portfolio of patents covering that specific drug. If other patents covering bevacizumab remain in force, they will continue to block biosimilar entry for bevacizumab, regardless of CA2455768's expiry.

Strategic Considerations for Biosimilar Developers:

• Freedom-to-Operate (FTO) Analysis: Comprehensive FTO analyses are critical. These analyses identify all relevant unexpired patents that could be infringed by the proposed biosimilar product, including those for manufacturing, formulation, and indication.
• Design Around Strategies: Developers may need to design around existing patents, for example, by developing a biosimilar with a slightly different but therapeutically equivalent formulation or manufacturing process.
• Timing of Market Entry: The timing of biosimilar market entry is often dictated by the expiry of key secondary patents and the successful navigation of patent litigation.

In summary, the expiry of CA2455768 signals a liberalization of the patent landscape concerning the fundamental anti-VEGF antibody technology it described. However, for any specific therapeutic product that originated from this technology, the path to market entry for biosimilars is still likely to be complex and heavily influenced by the patent portfolios of the originator companies.

Key Takeaways

• Canadian Patent CA2455768, granted in 2007 and expiring on May 13, 2024, protects anti-VEGF antibodies and their therapeutic uses.
• The patent claims specific antibody sequences, bispecific antibodies, pharmaceutical compositions, and methods for treating angiogenesis-dependent diseases.
• Its expiration removes a foundational intellectual property barrier for anti-VEGF antibody technologies in Canada.
• However, the broader Canadian patent landscape for anti-VEGF antibodies is characterized by extensive "patent thickets" held by originator companies.
• Biosimilar market entry requires not only the expiry of foundational patents like CA2455768 but also the absence of infringement on numerous secondary patents covering formulations, manufacturing, and specific indications.
• Comprehensive freedom-to-operate analyses and successful navigation of patent litigation remain critical for generic and biosimilar manufacturers.

Frequently Asked Questions

1. Does the expiry of CA2455768 mean that any company can immediately launch a bevacizumab biosimilar in Canada? No. While CA2455768 is expired, other patents covering bevacizumab, its manufacturing, formulations, or specific indications may still be in force. A biosimilar manufacturer must confirm freedom-to-operate across the entire patent landscape for the specific reference biologic.

2. What specific diseases were covered by the methods of treatment claims in CA2455768? The patent claims methods of treating angiogenesis-dependent diseases, which typically include various forms of cancer (e.g., colorectal, lung, breast, renal) and eye diseases such as age-related macular degeneration (AMD) and diabetic retinopathy.

3. Can F. Hoffmann-La Roche AG seek an extension of patent term for CA2455768? Under Canadian law, extensions of patent term are generally not available for patents that have expired. The patent term is fixed at 20 years from the filing date, subject to maintenance fees.

4. What is the significance of bispecific antibodies mentioned in CA2455768? Bispecific antibodies are engineered to bind to two different antigens. In the context of CA2455768, this could mean an antibody binding to VEGF and another target, such as a tumor cell receptor or an immune cell receptor, to enhance therapeutic delivery or efficacy beyond simple VEGF blockade.

5. How does the patent landscape for anti-VEGF antibodies differ in Canada compared to the United States or Europe? While core patentability principles are similar, specific patent term lengths, regulatory frameworks for biosimilars, and the details of patent litigation differ significantly between jurisdictions. Canada's Patent Medicine Price Control regulations and specific patent linkage rules also influence market dynamics.

Citations

[1] Genentech, Inc., & F. Hoffmann-La Roche AG. (2004). Anti-VEGF antibodies (Canadian Patent CA2455768). Canadian Intellectual Property Office. [2] Canadian Intellectual Property Office. (n.d.). Patent Register. Retrieved from https://ised-isde.canada.ca/cipo/