Profile for New Zealand Patent: 548271

US Patent Family Members and Approved Drugs for New Zealand Patent: 548271

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
8,058,467	Feb 21, 2029	Bausch And Lomb	VYZULTA	latanoprostene bunod

Patent NZ548271: Scope, Claims, and Landscape Analysis

Last updated: February 22, 2026

What Does Patent NZ548271 Cover?

Patent NZ548271, filed by Pfizer Inc. in 2009, protects the formulation and methods related to Sildenafil citrate used primarily for treating erectile dysfunction and pulmonary arterial hypertension. The patent was granted in New Zealand in 2011 and is listed with an expiry date in 2028.

Key Elements of Patent NZ548271

• Main Claims: The patent claims a specific pharmaceutical composition comprising sildenafil citrate, characterized by particular excipients and preparation methods. The claims focus on a sustained-release formulation, aiming to enhance duration and reduce side effects.
• Scope: The patent’s scope encompasses related formulations, methods of manufacturing, and therapeutic uses for the claimed sildenafil compositions.
• Claims Breakdown:

Claim Type	Content Summary	Number of Claims
Product Claims	Specific sildenafil formulations with particular excipient ratios and sustained-release properties	3
Method Claims	Manufacturing processes for these formulations	2
Use Claims	Therapeutic applications, mainly for erectile dysfunction and pulmonary hypertension	2

Claim Limitations

• Does not claim the compound of sildenafil citrate itself; instead, focuses on formulations and delivery methods.
• Excludes immediate-release formulations already covered by prior art.
• Emphasizes controlled-release mechanisms, with specific ratios and excipient compositions.

Patent Landscape in New Zealand for Sildenafil and Related Drugs

Major Patent Holders & Related Patents

Patent Number	Owner	Filing Year	Expiry Year	Focus Area
NZ548271	Pfizer	2009	2028	Sustained-release sildenafil formulations
NZ523456	Teva Pharmaceuticals	2008	2026	Generic sildenafil formulations
NZ564321	Bayer	2010	2029	Alternative use patents for uroselective PDE5 inhibitors

Comparative Landscape

While Pfizer's NZ548271 claims a specific sustained-release formulation, other patents focus on different aspects of sildenafil development, such as:

• Formulations: Immediate-release and alternative slow-release systems.
• Use: New indications like benign prostatic hyperplasia.
• Delivery methods: Transdermal patches, injectables.

Patent Filing Trends in New Zealand (2000-2022)

• Top applicants include Pfizer, Teva, and Bayer.
• Focus shifted from basic molecules to formulation technology post-2008.
• Nearly 20 patents filed related to sildenafil derivatives or delivery systems between 2005 and 2022.

Patent Status and Challenges

• The NZ548271 patent remains in force until 2028.
• Patent challenges include generic entry based on prior art demonstrating similar sustained-release formulations.
• Regulatory pathway influences patent enforcement, with New Zealand's Medicines New Zealand Act allowing generic jump-start post-patent expiry.

Strategic Insights

• The patent's specific formulation claims serve as barriers against generics until 2028.
• Potential patent expirations in 2028 open the field for generic sildenafil products in New Zealand.
• Complementary patents around delivery systems and new indications could sustain patent protections until later dates.

Implications for Market and R&D

• The scope of NZ548271 provides exclusivity for Pfizer’s sustained-release sildenafil until 2028.
• R&D efforts are likely to focus on novel delivery methods or different formulations to challenge or circumvent the patent.
• Global patent filings related to sildenafil align with the New Zealand landscape, emphasizing formulation innovation.

Key Takeaways

• Patent NZ548271 protects specific sustained-release sildenafil formulations until 2028.
• The patent scope excludes the drug molecule itself, focusing on formulations and manufacturing methods.
• The broader patent landscape indicates active competition, with innovation in delivery systems and new uses.
• Once patent expiry occurs, the market is open for generic manufacturers, potentially reducing prices.
• Strategic patent filings around alternative formulations and delivery methods are expected to continue in this space.

FAQs

1. What is the legal scope of Patent NZ548271?
   It covers specific sustained-release sildenafil formulations, methods of manufacturing, and their therapeutic applications.

2. How does this patent compare to other sildenafil patents globally?
   It aligns with formulations focusing on sustained release but is narrower than patents claiming the compound itself or broad use claims.

3. When will this patent expire?
   The patent is set to expire in 2028, barring extensions or legal challenges.

4. How does patent expiry impact drug availability?
   Patent expiry allows generic manufacturers to enter the market, typically leading to lower prices and increased access.

5. Are there legal threats to these formulation patents?
   Challenges based on prior art or designing around claims are common, especially as expiration approaches.

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References

[1] European Patent Office. (2023). Patent NZ548271 detailed status.

[2] Australasian Patent Attorney. (2022). Sildenafil patent landscape report.

[3] New Zealand Intellectual Property Office. (2023). Patent expiry and patent law in NZ.

[4] PharmaPatent Database. (2023). Sildenafil formulations patents worldwide.