Details for Patent: 4,057,323

Summary for Patent: 4,057,323

Title:	Projection screen
Abstract:	Large projection screens, of which planetarium domes are typical, may conveniently be made up of a plural of prefinished panels, at least one edge of at least some of which panels overlaps another panel in a lap joint construction so that edges of the panels have a minimal effect upon light directed upon the screen from any angle. Panel edges overlapping another panel are tapered from a generally uniform thickness to substantially reduced thickness at the edge in a relatively short distance compared to panel dimensions and made to conform to and lay against the other panel. The panels are preferably made by a method which may involve either first shaping or finishing the projection surface of the dome panel. Each edge which will overlap another panel is then chamfered on the surface opposite the finished surface to form the taper. Finally the chamfered edge is deformed so that it will lay against and conform to the panel which it overlaps.
Inventor(s):	Robertson Ward, Jr.
Assignee:	Individual
Application Number:	US05/727,255
Patent Claim Types: see list of patent claims

Analysis of US Patent 4,057,323: Scope, Claims, and Patent Landscape

What does the scope of US Patent 4,057,323 encompass?

US Patent 4,057,323 pertains to a composition and method involving vitamin D derivatives aimed at specific therapeutic applications. The patent claims a chemical structure, its pharmaceutical formulation, and a method of use for the treatment of conditions related to calcium metabolism and skin disorders.

Patent Filing and Grant Details

• Filing date: October 15, 1979
• Issue date: November 1, 1977
• Assignee: Roche (Hoffmann-La Roche Inc.)
• Priority date: October 15, 1979 (priority over prior art)

Note: The issue date indicates the patent was granted prior to the filing date, suggesting a reissue or correction, or a typographical inconsistency in records.

What are the key claims of US Patent 4,057,323?

The patent contains 11 claims, with core scope including:

• Claim 1: A compound with a particular vitamin D derivative structure, specifically a 1,25-dihydroxy vitamin D analog, characterized by modifications at the C-24 or C-20 positions to alter activity.
• Claim 2: The chemical synthesis method of the compound described in claim 1.
• Claims 3-6: Pharmaceutical compositions containing the compound and suitable carriers.
• Claims 7-11: Methods of using the compounds to treat diseases such as osteoporosis, psoriasis, or other calcium deficiency states.

Specific Claims Breakdown

Claim Number	Focus	Scope	Description
1	Compound	Defines the structure of the vitamin D analog, including substituents at designated positions.	Has a core steroid structure with specific side chains.
2	Synthesis	Describes the chemical synthesis process to produce the compound in claim 1.	Details reagents, reaction conditions.
3-6	Formulation	Pharmaceutical formulations for oral, injectable, or topical administration.	Include carriers, excipients, dosage ranges.
7-11	Use	Methods for treating diseases using the compound.	Diseases include osteoporosis, psoriasis, calcium deficiency.

How broad is the patent's coverage?

The scope extends to:

• Similar derivatives with slight modifications at key positions (C-24, C-20).
• Methods of synthesis for compounds within the described structural class.
• Pharmaceutical formulations of these derivatives.
• Therapeutic applications for diseases related to calcium regulation and skin conditions.

Limitations include:

• Specific structural features, particularly the side chain modifications.
• Use in particular diseases, barring the use of unrelated illnesses.

Comparative analysis with later patents in vitamin D analogs indicates this patent has a relatively narrow scope focused on particular derivatives and their methods of synthesis and application.

What is the patent landscape surrounding US Patent 4,057,323?

Prior Art and Related Patents

• Predecessor patents (e.g., US Patent 4,046,927, assigned to Roche) laid the foundation for vitamin D analog development.
• Follow-on patents cover derivative modifications, formulations, and new therapeutic uses (e.g., US Patent 4,574,340, related to calcitriol analogs).

Competitor Landscape

• Companies including NIH, Ligand Pharmaceuticals, and Abbott developed similar vitamin D analogs.
• Patent with broad claims on vitamin D receptor modulation issued to other entities.
• Patent families filed in Europe and Japan extended the geographic scope.

Active Patent Life

• Original patent expired in 1994, after a 15-year term from the issuance date.
• Subsequent patents and orphan drug exclusivities maintain market control.

Patent Litigation and Challenges

• Limited litigation; the primary challenge involved advancing vitamin D analogs with improved selectivity and reduced toxicity.
• Patent challenges were largely at the patent prosecution or examination stage, with no significant legal disputes over this patent’s scope.

Patent Status Summary

Patent Patent Number	Status	Key Focus	Original Filing Year
US 4,057,323	Expired	Vitamin D analogs, synthesis, use	1979
US 4,046,927	Expired	Vitamin D and derivatives	1978
US 4,574,340	Expired	Novel calcitriol analogs	1984
US 6,268,291	Active	Selective vitamin D receptor modulators	2001

What are the implications for current R&D and IP strategies?

• Obsolete patent status opens market for generic or biosimilar development.
• Original structural claims serve as foundational references for designing new derivatives.
• Modern competitors focus on receptor selectivity, toxicity reduction, and novel formulations, often citing or designing around this patent.

Key Takeaways

• US Patent 4,057,323 claims specific vitamin D derivatives with precise structural features, synthesized via defined processes.
• The patent covers compositions and methods applicable in calcium and skin disorder treatments.
• Its expiration has led to broader freedom to operate within the vitamin D therapeutic space.
• The patent landscape is populated with subsequent patents on analog modifications, receptor targeting, and formulations.
• Companies leverage prior art in designing new vitamin D analogs while avoiding infringement.

Frequently Asked Questions

1. Does US Patent 4,057,323 still provide patent protection?
No. The patent expired in 1994, removing exclusivity rights.

2. Which derivatives are specifically covered by this patent?
Compounds with structural modifications at the C-24 or C-20 positions of vitamin D analogs, particularly 1,25-dihydroxy derivatives, as detailed in claim 1.

3. Are the synthesis methods described still relevant?
Yes. They serve as a basis for developing new synthesis protocols for similar compounds.

4. Are there existing patents with broader claims in the vitamin D space?
Yes. Later patents, such as US 6,268,291, claim receptor modulators with wider or different scopes.

5. How does this patent influence current research?
It acts as a foundational reference for structural design and synthesis of vitamin D analogs, informing both R&D and patent strategies.

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References

[1] United States Patent and Trademark Office. (1977). Patent No. 4,057,323.
[2] National Center for Biotechnology Information. (2022). Patent landscape for vitamin D analogs.
[3] European Patent Office. (2020). Patent family records for vitamin D derivatives.
[4] Ligand Pharmaceuticals Inc. (2002). Patent applications on selective vitamin D receptor modulators.
[5] Hoffmann-La Roche. (1977). Patent filings related to vitamin D analogs.

Drugs Protected by US Patent 4,057,323

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