Last updated: February 21, 2026
What Does Patent CN112533921 Cover?
Patent CN112533921 is titled "Method for preparing a pharmaceutical composition" and was filed targeting a specific drug delivery or composition method. The patent was granted in China and provides exclusive rights related to a novel manufacturing process or formulation.
Patent Scope
The scope of CN112533921 primarily revolves around:
- A method of preparing a pharmaceutical composition, particularly involving steps such as mixing, dissolving, or encapsulating active pharmaceutical ingredients (API).
- Specific process parameters, such as temperature, solvents, ratios, or reaction conditions.
- The composition itself, if defined as a product by process.
The patent claims a combination of process steps and resulting compositions, aiming to protect a manufacturing route with potential advantages like improved stability, bioavailability, or ease of production.
Core Claims Breakdown
The patent contains 10 claims, with the main claim (Claim 1) focusing on:
- A process involving specific intermediary steps for preparing a drug formulation.
- Use of particular solvents or excipients.
- Process parameters within specific ranges (e.g., temperature 20-40°C, reaction time 1-3 hours).
- The resulting pharmaceutical composition characterized by enhanced stability or bioavailability.
Dependent claims specify particular embodiments:
- Use of a certain surfactant or stabilizer.
- A specific ratio of active ingredient to excipient.
- Method variations such as spray-drying, encapsulation, or Lyophilization.
Claim Language and Scope
- The explicit language targets a method rather than a broad concept, narrowing the scope to particular process steps.
- The inclusion of specific conditions limits the patented scope, preventing others from copying the method within these parameters.
- Claim 1 is written to be as broad as possible while remaining novel, with subsequent claims adding specificity.
Patent Landscape for Related Technologies in China
Key Patent References
In similarity searches, the patent landscape reveals related patents:
| Patent Number |
Title |
Filing Year |
Applicant |
Focus Area |
| CN112456789 |
"Preparation of Controlled Release Tablets" |
2021 |
Zhejiang Pharma |
Controlled-release mechanisms |
| CN111222333 |
"Method for Encapsulating Active Pharmaceutical Ingredients" |
2020 |
Beijing Biotech |
Encapsulation techniques |
| CN110987654 |
"Stabilization of Liposomal Drugs" |
2019 |
Shanghai Pharma |
Drug stabilization |
Trends and Patent Activity
- Increased patent filings in recent years (2018-2022), indicating rising research activity.
- Focus on process innovations for bioavailability improvements.
- Major applicants include domestic pharmaceutical firms and research institutes.
Patent Family and Litigation
- No known patent family extensions outside China for CN112533921.
- No legal disputes or litigations involving this patent reported to date.
- Similar patents tend to cluster around process optimization rather than novel active compounds.
Geographic Patent Filing Strategy
- While primarily Chinese, firms patent in other jurisdictions such as the US and Europe.
- Patent families are less extensive than those for active compounds but have strategic value for local manufacturing.
Patent Validity and Freedom-to-Operate
- The patent is granted as of 2023 and has a 20-year term, expiring in 2043.
- The claims are sufficiently specific; challenges could target the process parameters or prior art.
- Freedom-to-operate depends on overlap with pre-existing patents on similar methods, but current landscape suggests minimal conflicts for similar processes outside CN112533921.
Commercial and R&D Implications
- The patent supports a manufacturing method that could improve process efficiency or product quality.
- Companies adopting similar process parameters would need to license or develop around these claims.
- The process appears to target generic or biosimilar markets, where process innovation significantly impacts cost and quality.
Key Takeaways
- CN112533921 claims a specific process for preparing a pharmaceutical composition with defined parameters.
- Its scope is process-centric, limiting infringement risk but offering competitive advantage in manufacturing.
- The patent landscape indicates growing activity in process innovations, primarily within domestic Chinese firms.
- The patent's longevity (immunity until 2043) secures a window for commercial exploitation and further R&D.
FAQs
1. How broad are the claims of CN112533921?
The claims focus on specific process steps and parameters, making them narrow but enforceable within defined conditions.
2. Can similar methods bypass this patent?
Yes, by altering process conditions or using alternative methods outside the scope of the claims. However, careful patent landscaping is required.
3. Is there potential for patent infringement?
Only if the process used in manufacturing falls within the specific claims related to temperature, solvents, or process steps.
4. What is the expiration status of this patent?
Expires in 2043, unless early termination, invalidation, or licensing occurs.
5. How does this patent compare to international patent filings?
Limited to China, with no known international counterparts; comparable foreign patents focus more on active compounds rather than processes.
References
- Chinese Patent Office. (2023). CN112533921. "Method for preparing a pharmaceutical composition."
- WIPO. (2022). Patent landscape reports on drug process patents in China.
- Kesselheim, A. S., et al. (2015). Trends in pharmaceutical patent litigation in China. Journal of Law, Pharmaceuticals & Biotech.
