United States Patent 6,858,596: Scope, Claims, Expiration and Ciclesonide Nasal-Spray Patent Landscape

U.S. Patent No. 6,858,596 covers aqueous particulate suspensions of the compound identified in the patent as Formula (I), including unsolvated polymorph Form 1, for nasal delivery and inhalation. The claimed formulation architecture corresponds to ciclesonide nasal spray, marketed as Omnaris. The patent reaches beyond the marketed formulation through broad claims covering excipients, alternative preservatives, dosage ranges, combination therapies, nasal-spray containers, inhalers, and treatment of rhinitis, asthma, dermatitis, and COPD.

The patent issued on February 22, 2005. Its principal commercial relevance was protection of ciclesonide nasal suspension formulations for allergic rhinitis. The Orange Book-listed patent term ended in 2021, subject to any applicable pediatric exclusivity. It is therefore not an active barrier to a present-day FDA-approved generic ciclesonide nasal spray, although its claim structure remains relevant to historical litigation, freedom-to-operate analyses, and later formulation patents.[1-3]

What drug does U.S. Patent 6,858,596 protect?

The claimed Formula (I) compound is ciclesonide, a corticosteroid prodrug used in inhaled and intranasal products. Ciclesonide is practically insoluble in water and is administered as particulate material in an aqueous suspension.

The relevant product characteristics are:

Item	Description
Active ingredient	Ciclesonide
Therapeutic class	Intranasal corticosteroid
Representative product	Omnaris nasal spray
FDA indication	Seasonal and perennial allergic rhinitis
Dosage form	Aqueous nasal suspension
Commercial strength	50 mcg per actuation
Administration	Once daily
Patent at issue	U.S. 6,858,596
Core dosage-form concept	Particulate ciclesonide suspended in water
Solid-state limitation	Unsolvated polymorph Form 1 in dependent claim 20

The patent is not a broad composition-of-matter patent covering all ciclesonide. Its central protection is formulation-based. A product containing ciclesonide may avoid infringement if it does not use the claimed aqueous particulate suspension, falls outside the relevant claim limitations, or is protected by a different patent estate after the expiration of U.S. 6,858,596.

What is the core scope of claim 1?

Claim 1 requires a pharmaceutical formulation comprising:

An aqueous suspension;
Particulate compound of Formula (I), or a solvate of that compound.

The claim does not require a nasal route, a particular concentration, a preservative, a wetting agent, an isotonicity agent, or a specific container. Those limitations appear in dependent claims and method claims.

A formulation can therefore fall within claim 1 without including the full commercial excipient package. The minimum technical combination is an aqueous medium and particulate Formula (I) compound or solvate.

Claim 1 limitation analysis

Claim element	Scope and practical significance
Pharmaceutical formulation	Requires a medicinal composition rather than an isolated chemical or laboratory suspension
Aqueous suspension	Requires water-based liquid with dispersed solid particles
Particulate compound	Protects a solid-particle formulation, not merely dissolved ciclesonide
Formula (I) or solvate	Captures the identified active compound and certain solvated forms
No route limitation	Claim 1 can potentially reach nasal, inhaled, or other administration formats
No excipient limitation	A competing product need not use the Omnaris excipient package to implicate claim 1

The principal claim-construction issue is whether a proposed product contains the active ingredient as particulate material in an aqueous suspension. A fully dissolved solution would present a materially different infringement analysis, although ciclesonide's low aqueous solubility makes a true solution formulation technically difficult.

How do claims 2 through 22 protect the formulation composition?

Claims 2 through 22 narrow the basic suspension claim by adding excipient classes, specific ingredients, concentration ranges, pH, isotonicity, and solid-state form.

Suspending-agent claims

Claims 2 to 4 and 27 cover suspending agents. Claim 3 identifies microcrystalline cellulose and sodium carboxymethylcellulose. Claim 4 specifies a total suspending-agent concentration of 0.1% to 5% by weight.

Claim 27 expands the disclosed class to include:

Carboxymethylcellulose;
Veegum;
Tragacanth;
Bentonite;
Methylcellulose; and
Polyethylene glycol.

These claims create multiple fallback positions. A generic developer that avoids microcrystalline cellulose and sodium carboxymethylcellulose could still face an issue under the broader class claims if it uses another listed suspending agent.

Preservative claims

Claims 5 through 9 and 28 to 29 cover preservatives. The most commercially significant combination is:

Benzalkonium chloride; and
EDTA, also known as disodium edetate.

Claim 7 covers benzalkonium chloride at 0.001% to 1% by weight. Claim 8 covers EDTA. Claim 9 covers the combination of benzalkonium chloride and EDTA.

Claim 28 covers broader preservative categories, including quaternary ammonium compounds, mercurial agents, alcoholic agents, antibacterial esters, chelating agents, chlorhexidine, chlorocresol, sorbic acid and salts, and polymyxin. Claim 29 identifies specific examples such as benzethonium chloride, cetrimide, cetylpyridinium chloride, chlorobutanol, phenylethyl alcohol, benzyl alcohol, and parabens.

The preservative claims are composition-dependent. They are less likely to affect a preservative-free single-dose presentation, provided the product also avoids the broader independent formulation claims.

Wetting-agent claims

Claims 10 to 12 and 30 cover wetting agents. Claim 11 specifies polyoxyethylene (20) sorbitan monooleate, commonly known as polysorbate 80. Claim 12 gives a concentration range of 0.001% to 0.05% by weight.

Claim 30 extends coverage to pharmaceutically acceptable wetting agents selected from fatty alcohols, esters, and ethers.

Isotonicity and pH claims

Claims 13 to 16 and 31 cover isotonicity-adjusting agents. Claim 14 specifies dextrose, with claim 15 covering 0.1% to 10% by weight. Claim 31 lists sodium chloride, dextrose, and calcium chloride.

Claim 16 requires the formulation to be isotonic with fluids of the nasal cavity. This is a functional formulation limitation and may require comparative osmolarity evidence or product specifications.

Claims 17 and 18 cover buffering to pH 5 to 7, including hydrochloric-acid adjustment. A product outside that pH range may avoid these dependent claims but would not necessarily avoid claim 1 or other claims.

Concentration and polymorph claims

Claim 19 covers ciclesonide or solvate concentrations of 0.005% to 1% by weight. Claim 26 narrows that range to 0.01% to 0.5%.

Claim 20 protects use of unsolvated polymorph Form 1. This is a solid-state limitation that may require powder X-ray diffraction, thermal analysis, spectroscopy, or other analytical evidence. It can be particularly important because two products with the same active ingredient and excipients may differ in polymorphic form.

What is the strongest commercial formulation claim?

Claim 22 is the most product-specific claim. It requires:

Microcrystalline cellulose and sodium carboxymethylcellulose;
EDTA and benzalkonium chloride;
Polyoxyethylene (20) sorbitan monooleate; and
Dextrose.

This combination likely tracks the commercial ciclesonide nasal-spray formulation more closely than claim 1. It is narrower but easier to assess against a finished-product specification.

Claim 1 is broader in ingredient coverage. Claim 22 is stronger as a formulation fingerprint. Claim 20 adds a separate solid-state layer by requiring unsolvated Form 1.

What do claims 23 through 25 protect?

Claim 23 covers a container containing the formulation and suitable for delivery as a nasal spray. It adds a device or presentation limitation to the formulation.

Claims 24 and 25 cover treatment of allergic rhinitis, including once-daily administration. These are method-of-treatment claims rather than product claims.

The practical value of claim 25 depends on the dosing regimen used by a competing product. Once-daily dosing is a commercially relevant limitation because the marketed product uses once-daily administration, but the claim does not cover every ciclesonide product unless the formulation and treatment limitations are also met.

What do claims 32 through 39 cover?

Claims 32 to 35 cover combination formulations containing another therapeutically active agent. The additional agent may be:

A PDE4 inhibitor;
An antihistamine;
An anti-inflammatory agent; or
An anti-infective agent.

Claim 35 identifies methapyrilene or loratadine as antihistamines, NSAIDs as anti-inflammatory agents, and antibiotics or antivirals as anti-infectives.

Claims 36 to 39 expand the therapeutic and delivery scope to:

Rhinitis;
Dermatitis;
Asthma;
COPD;
Human or animal treatment;
Inhalation;
Nebulization;
Nasal administration; and
Inhalers containing the formulation.

These claims create potential coverage outside allergic rhinitis and outside a conventional nasal-spray bottle. They also increase validity exposure because treatment claims directed to multiple diseases and delivery routes may face distinct written-description, enablement, anticipation, obviousness, and subject-matter eligibility arguments.

How many patents protect Omnaris and ciclesonide nasal spray?

The relevant patent estate has historically included several categories:

Patent category	Protection provided	Relevance
Active-ingredient patents	Ciclesonide chemical compound and related compounds	Primarily historical composition-of-matter protection
Solid-state patents	Polymorphs, including Form 1	Protects the physical form used in the product
Formulation patents	Aqueous suspensions, excipients, pH, tonicity, and concentration	Core relevance of U.S. 6,858,596
Device or container patents	Nasal-spray presentation and delivery components	Potentially relevant to product configuration
Method-of-use patents	Allergic rhinitis and other respiratory conditions	May affect labeled-use theories
Manufacturing patents	Particle production, crystallization, micronization, and suspension preparation	Can create process and supply-chain barriers

U.S. Patent 6,858,596 is the central U.S. formulation patent identified in the supplied claims. A complete current Orange Book and patent-family review should distinguish expired U.S. rights from any later-issued continuation, reissue, foreign rights, or unlisted manufacturing patents.

When did U.S. Patent 6,858,596 lose exclusivity?

The patent issued February 22, 2005. The Orange Book-listed patent term for U.S. 6,858,596 ended in 2021. Any six-month pediatric exclusivity associated with the product would have extended the regulatory protection period beyond the patent expiration date, but the underlying patent itself was not a current barrier after its listed expiration.[2]

The patent term must be separated from FDA regulatory exclusivity:

Protection	Function	Status
U.S. 6,858,596 patent	Formulation and related method protection	Expired in 2021
Pediatric exclusivity, if applicable	Six-month FDA protection extension	Separate from patent term
FDA approval exclusivity	Regulatory exclusivity attached to the NDA	Separate from patent rights
Current generic competition	Controlled by active patents, exclusivities, ANDA status, and product availability	Requires current FDA records

Patent expiration does not invalidate the historical value of the patent. It eliminates the ability to obtain prospective injunctive relief for ordinary post-expiration infringement, while leaving possible historical damages issues subject to applicable limitations periods and litigation posture.

Were there Paragraph IV challenges?

A Paragraph IV certification is relevant only while an Orange Book-listed patent is active or otherwise remains legally consequential to an ANDA applicant. For ciclesonide nasal spray, the commercial generic pathway became materially more accessible after the expiration of the principal formulation patent and any associated regulatory protection.

The supplied record does not establish a specific Paragraph IV notice, ANDA number, challenger, settlement, or district-court docket tied to U.S. 6,858,596. Accordingly, no particular Paragraph IV challenger or settlement should be treated as confirmed from the claims alone.

The relevant legal distinction is:

A Paragraph IV certification alleges that a listed patent is invalid, unenforceable, or not infringed.
A Section viii statement removes a patented method of use from the proposed label.
A post-expiration ANDA may rely on patent expiration rather than litigating an active formulation patent.
A product can still face litigation under non-Orange-Book patents, including manufacturing or polymorph patents.

What is the FDA and Orange Book status of ciclesonide nasal spray?

Omnaris was approved by FDA for treatment of seasonal and perennial allergic rhinitis. The product contains ciclesonide in an aqueous nasal suspension and is administered once daily.[3]

The Orange Book is the principal FDA source for listed patents and exclusivity information for approved small-molecule products.[2] It does not provide a complete patent landscape. It generally does not capture every manufacturing patent, foreign patent, unpublished application, trade secret, or patent that a competitor may assert outside the ANDA context.

Ciclesonide is a small molecule, not a biologic. Biosimilar analysis under the Public Health Service Act is therefore not applicable. Competition proceeds through the ANDA pathway, subject to the relevant listed patents, regulatory exclusivity, bioequivalence requirements, device considerations, and product-specific FDA requirements.

What generic launch risks exist?

A generic ciclesonide nasal spray would generally need to address five technical issues:

Particle-size distribution and suspension stability;
Polymorphic form of ciclesonide;
Nasal-device performance and delivered-dose uniformity;
Preservative and excipient differences; and
Bioequivalence for a locally acting nasal product.

The expired status of U.S. 6,858,596 reduces patent risk but does not eliminate development risk. A generic may still need to demonstrate that its formulation has suitable particle characteristics, dose delivery, microbial quality, stability, and local nasal performance.

Potential design-around strategies historically could include:

A different preservative system;
A preservative-free multidose or unit-dose presentation;
A different suspending agent;
A different wetting agent;
A different isotonicity agent;
A formulation outside the claimed concentration ranges;
A different polymorphic form, if technically and regulatorily acceptable;
A different delivery device; or
A nonaqueous or solution-based approach, if feasible.

Each strategy must be assessed against all independent and dependent claims, not merely claim 22.

How strong is the patent estate?

The patent was commercially meaningful because it combined broad claim 1 with numerous dependent formulation claims. Its strengths were:

Coverage of the fundamental aqueous suspension format;
Multiple excipient fallback claims;
Specific protection for benzalkonium chloride and EDTA;
Coverage of polysorbate 80 and dextrose;
A pH range suited to nasal administration;
Concentration ranges covering the commercial product;
Solid-state protection for Form 1; and
Method and container claims extending beyond the bulk formulation.

Its weaknesses were structural:

The patent did not claim ciclesonide itself at the composition-of-matter level;
Many claims depend on conventional pharmaceutical excipients;
Several dependent claims are narrow and potentially easy to design around;
Functional claims such as nasal isotonicity may require fact-intensive proof;
Broad treatment and delivery claims may face enablement and obviousness challenges;
The patent is expired.

The practical conclusion is that U.S. 6,858,596 was a strong historical formulation patent but is no longer a current U.S. exclusivity asset.

What licensing and litigation issues should companies evaluate?

A current transaction involving ciclesonide nasal spray should separate:

Rights under the expired U.S. formulation patent;
Any continuing foreign patent rights;
Later continuation or divisional patents;
Device patents;
Manufacturing and particle-engineering patents;
Trade secrets relating to micronization or suspension processing;
Regulatory exclusivity;
ANDA litigation history; and
Supply rights for ciclesonide API and finished product.

No licensing deal, settlement agreement, or specific litigation outcome is established by the claims provided. The patent record alone does not prove that a license was granted or that a Paragraph IV dispute was settled.

Key Takeaways

U.S. Patent 6,858,596 is directed to aqueous particulate formulations of ciclesonide, not to ciclesonide as a chemical compound.
Claim 1 is broad and requires an aqueous suspension containing particulate Formula (I) compound or solvate.
Claims 2 through 22 cover suspending agents, preservatives, wetting agents, isotonicity agents, pH, concentration, and polymorphic Form 1.
Claim 22 most closely tracks the commercial formulation combination of microcrystalline cellulose, sodium carboxymethylcellulose, EDTA, benzalkonium chloride, polysorbate 80, and dextrose.
Claims 23 through 25 cover nasal-spray containers and once-daily allergic-rhinitis treatment.
Claims 32 through 39 extend to combination products, inhalers, nebulization, asthma, COPD, dermatitis, and rhinitis.
The patent expired in 2021 and is not a current U.S. patent barrier to generic entry.
Ciclesonide is a small molecule, so biosimilar rules do not apply.
Current diligence should focus on later patents, device rights, manufacturing patents, ANDA records, and FDA-listed exclusivity rather than the expired patent alone.

FAQs

Does U.S. Patent 6,858,596 cover all ciclesonide products?

No. It primarily covers ciclesonide in an aqueous particulate suspension and related formulations. A ciclesonide product using a different dosage form or delivery architecture requires a separate infringement analysis.

Does claim 20 require a specific ciclesonide polymorph?

Yes. Claim 20 requires unsolvated polymorph Form 1. Analytical characterization would be needed to determine whether a proposed product contains that form.

Can a preservative-free ciclesonide nasal spray avoid the patent?

It may avoid certain preservative-dependent claims, but it would not automatically avoid claim 1 or other claims that do not require a preservative.

Is a ciclesonide nasal spray subject to biosimilar competition?

No. Ciclesonide is a small molecule. The relevant pathway is an ANDA for a generic drug, not a biosimilar application.

Does patent expiration guarantee immediate generic availability?

No. Generic availability also depends on FDA approval, bioequivalence, device performance, manufacturing capacity, regulatory exclusivity, and any later active patents.

References

United States Patent and Trademark Office. (2005). U.S. Patent No. 6,858,596, Pharmaceutical formulations.
U.S. Food and Drug Administration. (n.d.). Approved drug products with therapeutic equivalence evaluations, Orange Book.
U.S. Food and Drug Administration. (2006). Omnaris ciclesonide nasal spray prescribing information.

Foriegn Application Priority Data
Foreign Country	Foreign Patent Number	Foreign Patent Date
United Kingdom	0019172	Aug 05, 2000

Country	Patent Number	Estimated Expiration	Supplementary Protection Certificate	SPC Country	SPC Expiration
European Patent Office	1305329	⤷ Start Trial	91429	Luxembourg	⤷ Start Trial
European Patent Office	1305329	⤷ Start Trial	CA 2008 00022	Denmark	⤷ Start Trial
European Patent Office	1305329	⤷ Start Trial	300343	Netherlands	⤷ Start Trial
European Patent Office	1305329	⤷ Start Trial	SPC011/2008	Ireland	⤷ Start Trial
>Country	>Patent Number	>Estimated Expiration	>Supplementary Protection Certificate	>SPC Country	>SPC Expiration

Details for Patent: 6,858,596

Summary for Patent: 6,858,596