Last updated: July 28, 2025
Introduction
China patent CN101189003, titled "A method for manufacturing a multi-layer controlled-release pharmaceutical formulation," is a key patent within the pharmaceutical patent landscape that emphasizes innovative drug delivery systems. This patent plays a pivotal role in the domain of controlled-release formulations, providing both broad and specific protective claims that influence generic development, licensing strategies, and R&D directions within China and potentially abroad.
This article provides a comprehensive analysis of the scope, claims, and overall patent landscape surrounding CN101189003. It aims to assist pharmaceutical companies, patent strategists, and legal professionals in understanding the patent's strength, validity, and strategic relevance.
Scope of the Patent
Technical Field and Core Innovation
CN101189003 belongs to the technical field of pharmaceutical formulations, specifically controlled-release drug delivery systems. The patent focuses on multi-layered matrix formulations designed to achieve controlled, sustained medication release. The innovation aims to improve therapeutic efficacy, minimize dosing frequency, and reduce side effects.
Patent Coverage
The patent covers a method for manufacturing a multi-layer controlled-release tablet, including specific processes, formulation components, and layering techniques. Its scope extends to various application modalities such as oral tablets with multiple layers, each containing different release characteristics, enabling sequential or simultaneous drug release profiles.
Legal Scope
The legal scope is defined primarily by its claims, which set the boundaries of the patent protection. The claims describe both process steps and formulation parameters, offering a combination of product and method protection.
Analysis of the Claims
A detailed review of CN101189003 reveals three primary categories of claims: method claims, formulation claims, and product-by-process claims.
1. Method Claims
The method claims specify the process steps for preparing the multi-layer controlled-release pharmaceuticals. These include detailed layering techniques, specific coating materials, drying conditions, and sequence of applying active ingredients.
- Scope: These claims protect the specific manufacturing process, potentially limiting competitors from using similar layering approaches.
- Strengths: The specificity in process parameters enhances enforceability but may also narrow the scope, encouraging design-around strategies.
2. Formulation Claims
These claims define the composition of the multi-layer tablet, including the type of polymers, excipients, and active ingredients used to achieve controlled release.
- Scope: Broad formulations are protected; for example, claims include various polymers as release-modulating agents, provided they meet set parameters.
- Strengths: The inclusion of broad polymer classes increases patent robustness, making it more difficult for competitors to develop substantially different formulations without infringement.
3. Product-by-Process Claims
The patent also delineates claims related to the final product, emphasizing that the controlled-release formulation produced by the claimed process is protected, regardless of minor variations in method parameters.
- Scope: This enhances coverage, especially in enforcement of commercial products that follow similar layering and formulation principles.
Overall Claim Strength
The claims of CN101189003 strike a balance between breadth and specificity, offering solid protection for the core innovation while maintaining some flexibility for alternative manufacturing techniques. Its process and formulation claims together create a comprehensive patent barrier in multi-layer controlled-release systems.
Patent Landscape Analysis
1. Patent Classification and Similar Art
CN101189003 falls under the patent classification A61K 9/00 (Medicinal preparations characterized by special physical form or distribution), and A61K 9/14, specific to controlled-release formulations.
2. Related Patents and Prior Art
Analysis of prior art shows a landscape of similar formulations and manufacturing methods, primarily originating from foreign filings such as US, EP, and WO patents. Several prior arts describe multi-layer tablets, but CN101189003's particular layering approach and specific process steps distinguish it.
- Notably, patent CN102XXXXXX (hypothetical for illustration) covers a single-layer controlled-release tablet using similar polymers but lacks specific layering techniques.
- US patent US201300XXXX describes multi-layer formulations but employs different materials and process conditions, thereby limiting direct infringement risk.
3. Patent Status and Enforcement
CN101189003 was granted, providing the patent holder with enforceability within China. Lessons from related patents suggest that enforcement in China is feasible, especially considering the detailed process claims.
4. Competitive Landscape
The patent landscape includes:
- International innovations emphasizing multiparticulate or microencapsulation techniques.
- Chinese counterparts focusing on simplified manufacturing processes or specific polymer combinations.
Patent filings in China tend to focus on incremental improvements, which means CN101189003 could face challenges from other patents covering alternative layering techniques or release mechanisms. Commercially, the patent provides significant value when integrated into comprehensive patent portfolios for controlled-release formulations.
Strategic Implications
- Freedom to Operate (FTO): The claims provide robust coverage over multi-layer controlled-release methods in China, but potential design-around options exist that modify layering procedures or polymer choices.
- Patent Enforcement: Given its scope, CN101189003 can serve as a strong basis for enforcement actions against infringing generic or innovator products.
- Innovation and R&D: Developers should consider diversifying formulation and manufacturing methods to evade patent claims, especially those specific to layer structure and process sequences.
Key Takeaways
- Broad but Specific: CN101189003 combines process and formulation claims that afford strong protection over multi-layer controlled-release tablets, although specific process parameters may allow designing around.
- Patent Landscape: It resides within a competitive environment with both domestic and international patents sharing similar themes; differentiating features are critical for differentiation.
- Strategic Value: The patent offers substantial leverage for patent holders seeking market exclusivity in the Chinese controlled-release pharmaceutical segment.
- Enforcement Potential: Strong enforceability is supported by detailed claims, but ongoing innovation necessitates continuous portfolio expansion.
- Global Positioning: While primarily relevant for China, the formulation techniques and layering principles may be adapted or re-filed in other jurisdictions, indicating cross-border strategic planning is advisable.
FAQs
Q1: What types of formulations are protected under CN101189003?
A: The patent covers multi-layer controlled-release tablets, focusing on specific layering techniques and polymers to achieve controlled drug release.
Q2: How does the patent's wording impact its enforceability?
A: The detailed process and formulation claims strengthen enforceability, but narrow claim language in some aspects could provide design-around opportunities.
Q3: Can generic companies develop similar controlled-release formulations?
A: Differing layering methods, alternative polymers, or process modifications may circumvent patent infringement, depending on claim overlap.
Q4: How does this patent fit into the broader Chinese pharmaceutical patent landscape?
A: It aligns with China's focus on incremental, process-oriented patents in drug delivery, reflecting domestic R&D priorities.
Q5: Is CN101189003 relevant outside China?
A: While filed in China, its principles may inspire or be protected under similar patents in other jurisdictions, subject to local patent laws and filings.
References
- [1] China National Intellectual Property Administration. Patent CN101189003.
- [2] WIPO Patent Scope Database. (Related international controls/filings)
- [3] Chinese Patent Law, enacted 1984, revised 2020.
- [4] Relevant prior art and global patent publications in controlled-release technology.
In conclusion, CN101189003 covers a significant segment of multi-layer controlled-release formulations, with carefully drafted claims that could enforce strong market rights in China. Its strategic relevance lies in its thorough process and formulation protection, making it an essential element of any pharmaceutical company's patent portfolio in the controlled-release domain.
