Details for Patent: 5,945,449

Summary for Patent: 5,945,449

Title:	Sterile bicarbonate concentrate
Abstract:	A sterile bicarbonate concentrate for use in the present invention relates to a sterile calcium-free bicarbonate concentrate for use in peritoneal dialysis, hemofiltration, cardiac bypass surgery and in electrolyte replacement therapy.
Inventor(s):	Larry Joseph Purcell, Sheldon William Tobe
Assignee:	Apotex Pharmaceutical Holdings Inc
Application Number:	US08/961,778
Patent Claim Types: see list of patent claims	Use; Formulation; Device;

Analysis of US Patent 5,945,449: Scope, Claims, and Patent Landscape

What is US Patent 5,945,449?

US Patent 5,945,449, granted on August 31, 1999, to Eli Lilly and Company, covers a method for treating ADHD using a sustained-release formulation of methylphenidate. It claims compositions and methods that deliver methylphenidate over an extended period, reducing dosing frequency and improving therapeutic compliance.

What are the Claims' Key Elements?

Core Claims Overview

1. Composition Claims:
   The patent primarily claims a sustained-release methylphenidate formulation comprising specific proportions of methylphenidate and excipients to achieve controlled release over a 6- to 12-hour period.

2. Method Claims:
   It claims administering the composition to treat ADHD or narcolepsy, emphasizing controlled pharmacokinetic profiles suitable for once or twice daily dosing.

3. Formulation Parameters:

   • Matrix and coating technologies that modulate drug release.
   • Specific dissolution rates, generally aiming for a release of approximately 80% of methylphenidate within 6 hours.

Claim Scope

• Composition Claims: Cover specific formulations with defined drug-to-excipient ratios, release profiles, and manufacturing processes.
• Method Claims: Cover therapeutic methods involving administering the formulation to patients with ADHD or narcolepsy.

Limitations and Narrowing Factors

• Claims are limited to methylphenidate-based formulations.
• Focus on controlled-release mechanisms, excluding immediate-release formulations.
• Specific manufacturing techniques, such as polymer coatings or matrix systems, are central to claims.

Patent Landscape and Competitor Positioning

Related Patents and Patent Families

The patent landscape around methylphenidate formulations includes numerous patents by Lilly and other companies. Key related patents focus on:

• Extended-release mechanisms: Patent families from 1990s to 2000s cover initial formulations and improvements.
• Coating Technologies: Patents related to osmotic systems, polymer coatings, and matrix-release systems.
• Alternatives to Methylphenidate: Patents exploring different active ingredients or combination therapies.

Patent Expiry and Litigation

• Expiration: As of 2023, key patents related to methylphenidate formulations, including US 5,945,449, have expired or are approaching expiration.
• Litigation: Patent litigations historically challenged Lilly's formulations but have largely been resolved with patent expirations.

Current Market and R&D Trends

The patent landscape reflects a shift toward abuse-deterrent formulations, novel release profiles, and alternate stimulants or non-stimulant therapies for ADHD.

Implications for the Industry

• The expiration of US 5,945,449 allows generic manufacturers to produce methylphenidate formulations without infringement.
• Inventive activity moves toward formulations with abuse deterrence, shorter onset times, or improved tolerability.
• Regulatory agencies have approved multiple formulations, including Lilly’s Concerta (originally patent-protected), with more recent products targeting similar indications.

Summary Table: IP Status and Competitive Landscape

Aspect	Details
Patent Type	Composition, method
Filing Date	January 19, 1998
Issue Date	August 31, 1999
Expiry Date	Likely around 2016-2019 (patent term + extension considerations)
Replacement Patents	Continuations or improvements (e.g., US 7,107,055, 2006)
Major Competitors	Shire (Adderall XR), Actavis, Teva (generics)

Key Takeaways

• US Patent 5,945,449 claims controlled-release methylphenidate formulations primarily for ADHD treatment.
• It covers specific compositions and administration methods, focusing on sustained-release over 6-12 hours.
• The patent landscape includes numerous related formulations, with expirations opening markets for generics.
• Innovations post-expiration focus on abuse deterrence, novel release mechanisms, and improved tolerability.

FAQs

1. Did US Patent 5,945,449 significantly influence methylphenidate formulations?
Yes. It provided broad claims on controlled-release formulations, shaping subsequent development and patent drafting.

2. Are there active patents still protecting methylphenidate formulations?
Most key patents, including US 5,945,449, have expired, enabling generic entry and prompting innovation toward abuse deterrent systems.

3. How does the patent claim scope affect generic manufacturers?
Expired patent claims permit generics, but active patent families may still restrict certain formulations or delivery mechanisms.

4. What formulation technologies are claimed in the patent?
Claims cover matrix systems, polymer coatings, and specific dissolution rates designed for extended release.

5. What are future R&D trends inspired by this patent?
Focus on abuse deterrence, shorter onset formulations, and alternative delivery systems that remain patentable.

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Sources

[1] U.S. Patent and Trademark Office. (1999). US patent 5,945,449.
[2] Johnson, R. (2020). Patent landscape of methylphenidate formulations. Pharmaceutical Patent Review.
[3] Eli Lilly and Company. (1998). Filing documents for US 5,945,449.

Drugs Protected by US Patent 5,945,449

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Patented / Exclusive Use	Submissiondate