United States Patent 8,633,162: Claim Scope, Restasis Patent Landscape, Generic Entry and Litigation Risk

U.S. Patent No. 8,633,162 protects twice-daily treatment of dry eye disease with a specific low-dose cyclosporine ophthalmic emulsion. The patent is directed to methods of use, not to cyclosporine as a molecule or to every cyclosporine eye-drop formulation. Its core combination is cyclosporin A at about 0.05% by weight, castor oil at about 1.25%, polysorbate 80, an acrylate/C10-30 alkyl acrylate cross-polymer, water, and twice-daily topical administration.

The patent is associated with the Restasis product franchise, originally developed and commercialized by Allergan and later owned by AbbVie. The patent’s scheduled term was tied to an August 2006 priority date and generally ran through August 2025, subject to any patent-term adjustment, terminal disclaimer, or other record-specific modification. The commercial risk shifted before expiration because generic cyclosporine ophthalmic emulsions entered the U.S. market through ANDA litigation and settlements.

What does U.S. Patent 8,633,162 protect?

Patent 8,633,162 protects a method of treating dry eye disease by administering a defined ophthalmic emulsion to a human eye twice daily. The patent does not claim all uses of cyclosporine, all dry-eye treatments, or all ophthalmic emulsions.

The independent claims are claims 1, 18 and 23:

Claim	Claim type	Principal limitation
1	Method of treating dry eye disease	Twice-daily administration of an emulsion containing about 0.05% cyclosporin A and about 1.25% castor oil, with specified excipients
18	Method of reducing side effects	Twice-daily administration of a fully specified emulsion with pH 7.2 to 7.6
23	Method of treating dry eye disease	Twice-daily administration of a fully specified formulation, including glycerine and sodium hydroxide

Claims 2-17 depend from claim 1. Claims 19-22 depend from claim 18, and claim 24 depends from claim 23.

The claim set therefore has two protection layers:

A broader formulation-and-regimen method in claim 1.
Narrower formulations and therapeutic-performance limitations in claims 18 and 23.

What formulation is required by the patent?

The central formulation includes the following ingredients:

Component	Claimed concentration or requirement
Cyclosporin A	About 0.05% by weight
Castor oil	About 1.25% by weight
Polysorbate 80	Present; about 1.0% in dependent claims
Acrylate/C10-30 alkyl acrylate cross-polymer	Present; about 0.05% in dependent claims
Glycerine	Present in certain claims; about 2.2% in claims 9, 18 and 23
Sodium hydroxide	Buffer limitation in claims 5, 10, 19 and 23
Water	Required
pH	About 7.2 to about 7.6 in claims 12, 18 and 24
Administration	Topical, to the eye, twice daily
Indication	Dry eye disease or dry eye syndrome

The formulation corresponds closely to the commercial Restasis 0.05% cyclosporine ophthalmic emulsion. The patent’s claim architecture places substantial weight on the excipient system and administration schedule rather than on cyclosporine alone.

Why are castor oil and polysorbate 80 important?

Castor oil is the principal oil phase identified in the claims. Polysorbate 80 is an emulsifier and solubilizing component. The combination supports a dispersed ophthalmic emulsion containing a poorly water-soluble active ingredient.

A product with cyclosporine at 0.05% but a different oil phase, different emulsifier system, or different dosing frequency would not necessarily fall within claim 1. Infringement analysis would require comparison of the commercial product’s qualitative and quantitative formulation, labeled dosing instructions, and actual method of use.

How broad is claim 1?

Claim 1 is broader than claims 18 and 23 because it does not require every excipient concentration recited in the narrower claims. It requires:

A human patient in need of treatment.
Dry eye disease.
Topical ocular administration.
Twice-daily dosing.
An emulsion.
About 0.05% cyclosporin A.
About 1.25% castor oil.
Polysorbate 80.
Acrylate/C10-30 alkyl acrylate cross-polymer.
Water.
Therapeutic effectiveness.

The terms “about 0.05%” and “about 1.25%” create numerical flexibility, but the breadth is constrained by the full ingredient combination. The claim does not expressly require glycerine, sodium hydroxide, or a specific pH. Those limitations appear in dependent claims.

Claim 1 is therefore most relevant to a competing product that uses the same active concentration, oil concentration and polymer-emulsifier system but varies secondary excipients.

Which claims are narrowest and potentially strongest?

Claims 23 and 24 are the most formulation-specific dry-eye claims. Claim 23 requires:

0.05% cyclosporin A.
1.25% castor oil.
1.0% polysorbate 80.
0.05% acrylate/C10-30 alkyl acrylate cross-polymer.
2.2% glycerine.
Sodium hydroxide.
Water.
Twice-daily administration.
Effectiveness in treating dry eye disease.

Claim 24 adds a pH range of 7.2 to 7.6.

Claims 18-22 are directed to reducing side effects while treating dry eye syndrome. They impose substantially similar compositional limitations and require a pH range. Claims 21 and 22 add systemic exposure and therapeutic-effect limitations.

Narrow claims are generally easier to design around but can be stronger against a product that matches the commercial formulation exactly.

What do the comparative and pharmacokinetic limitations add?

Claims 11 and 21 require that blood contain “substantially no detectable concentration” of cyclosporin A after administration. Claims 13 and 14 compare the claimed 0.05% formulation with a second emulsion containing 0.1% cyclosporin A and 1.25% castor oil. Claim 15 addresses faster breakdown in the eye and reduced vision distortion. Claims 16 and 17 address reduced adverse events or side effects.

These limitations have different litigation value:

Claim feature	Practical effect
Twice-daily dosing	Excludes products labeled or used at materially different frequencies
“Substantially no detectable concentration”	Creates an analytical and detection-limit issue
Therapeutic effectiveness	Requires evidence that the treatment works for dry eye disease
Comparative effectiveness	May require comparison against the specified 0.1% formulation
Reduced side effects	Requires clinical or empirical support linking the formulation to the claimed result
Faster breakdown and reduced vision distortion	Creates a performance-based infringement question

Functional limitations can be useful when a competing product has the same composition and regimen. They can also create vulnerability in enforcement because infringement may depend on clinical testing, assay sensitivity, claim construction and whether the result is inherent in the accused product.

What is the patent’s expiration date?

The patent traces to an August 2006 priority period. Its ordinary statutory term was generally expected to end in August 2025, subject to the official patent file for any patent-term adjustment or terminal disclaimer.

The critical commercial point is that the patent was not expected to provide long-term exclusivity after 2025. The Restasis franchise faced generic competition before or around the end of the patent term because ANDA applicants challenged the listed patents under Paragraph IV.

Event	Approximate timing
Priority period	August 2006
Patent application and continuation activity	2000s-2010s
U.S. patent issuance	January 2014
Scheduled term endpoint	August 2025, subject to record-specific adjustment
Generic entry pressure	Material before the scheduled expiration

Patent expiration does not eliminate other exclusivity, regulatory, formulation, manufacturing or trade-secret barriers. It does, however, remove the principal statutory exclusion right provided by this patent.

What is the Orange Book status of U.S. Patent 8,633,162?

Patent 8,633,162 was listed in connection with Restasis, NDA 050790, as a patent relevant to the approved cyclosporine ophthalmic emulsion product. Orange Book listings for Restasis included a group of formulation and method patents, not only Patent 8,633,162.

An Orange Book listing does not establish that every listed claim is valid or infringed. It provides the regulatory notice mechanism that requires an ANDA applicant to certify to listed patents. A Paragraph IV certification states that a listed patent is invalid, unenforceable or will not be infringed by the proposed generic product.

The practical impact of the listing was to trigger patent litigation when generic applicants sought approval before expiration.

Which companies challenged the Restasis patent estate?

The principal generic challengers included Teva Pharmaceuticals, Mylan and other ANDA applicants seeking approval for cyclosporine ophthalmic emulsion 0.05%.

The litigation focused on a broader Restasis patent estate that included formulation, manufacturing and method-of-use patents. The asserted patents varied by defendant and procedural stage. The key business issue was whether generic applicants could obtain FDA approval and launch before the full listed patent estate expired.

What was the result of the Restasis patent litigation?

Restasis litigation produced settlements and negotiated launch arrangements rather than a single final invalidity judgment eliminating the entire patent estate. Generic entry subsequently occurred through approved cyclosporine ophthalmic emulsion products.

The litigation history demonstrates an important distinction:

A Paragraph IV challenge creates litigation risk.
A settlement can establish an agreed launch date.
FDA approval does not itself resolve patent infringement.
Expiration of one patent does not necessarily eliminate other listed patents.
A generic launch may occur under a settlement before all asserted patents expire.

The commercial result was erosion of Restasis exclusivity through generic competition, even though the branded product retained clinical recognition and prescription demand.

What generic entry risks exist for a cyclosporine 0.05% ophthalmic emulsion?

A generic applicant pursuing the Restasis reference product can use the ANDA pathway if it demonstrates pharmaceutical equivalence and bioequivalence or satisfies the applicable FDA requirements for the product. The primary product-level risks are:

Patent infringement under the Orange Book listing.
Difficulty matching the emulsion’s physical characteristics.
Manufacturing variability affecting droplet size, viscosity and stability.
Challenge to the formulation’s equivalence despite matching active concentration.
Market-access restrictions created by settlement agreements.
Product liability or substitution risk if tolerability differs.

The product is not a biosimilar. Cyclosporine is a chemically defined small-molecule immunosuppressant, and cyclosporine ophthalmic emulsion is regulated through the generic-drug framework rather than the biologics biosimilar pathway.

Are biosimilar risks relevant to Patent 8,633,162?

No. Biosimilar risk is not the appropriate framework for cyclosporine ophthalmic emulsion.

The relevant competitive products are generic versions of the reference listed drug. A generic manufacturer does not need to establish biosimilarity. It must satisfy FDA requirements applicable to the ANDA product, including pharmaceutical equivalence and the required evidence of therapeutic equivalence or substitutability.

The patent still matters because the ANDA pathway permits an applicant to challenge listed patents before approval or commercial launch.

What formulation patents compete with Patent 8,633,162?

The Restasis estate included patents directed to more than the twice-daily low-dose method. Related patents addressed:

Cyclosporine ophthalmic emulsions.
Specific oil and surfactant systems.
Polymer-based emulsion stabilization.
Manufacturing or processing features.
Dry-eye treatment regimens.
Reduced systemic exposure.
Clinical tolerability and visual disturbance.

Patent 8,633,162 is best characterized as a method-of-use patent with detailed formulation limitations. It should be analyzed alongside the related Restasis formulation patents rather than in isolation.

A competing product can avoid this patent in several ways:

Design-around strategy	Potential effect
Use a different cyclosporine concentration	May avoid the 0.05% limitation, depending on the “about” range
Use a different oil or oil concentration	May avoid the castor-oil limitation
Replace polysorbate 80	May avoid claim 1 and narrower claims
Replace the acrylate cross-polymer	May avoid the core formulation combination
Use a different dosing schedule	May avoid twice-daily method claims
Modify glycerine, sodium hydroxide or pH	May avoid claims 18-24
Change indication or labeling	May affect method-of-use exposure, but does not eliminate all infringement theories

A design-around must be evaluated against every asserted patent, not only Patent 8,633,162.

How strong is the patent estate for commercial enforcement?

Patent 8,633,162 has meaningful commercial relevance because it combines a marketed formulation with a specific treatment regimen. Its strongest enforcement position is against a product that replicates the Restasis formulation and is labeled for twice-daily dry-eye treatment.

Its principal weaknesses are structural:

The claims are limited to a particular excipient combination.
Several dependent claims require narrow composition ranges.
Comparative claims require evidence against another emulsion.
Pharmacokinetic claims may depend on assay sensitivity.
Functional results such as reduced side effects can create proof disputes.
The patent term was approaching expiration when generic competition intensified.

The broader Restasis estate had greater blocking value than this patent alone. A challenger that successfully avoided or invalidated Patent 8,633,162 could still face other formulation or method patents.

What revenue exposure did the patent protect?

Restasis was a major ophthalmology product and one of Allergan’s leading assets before generic competition. The product generated multibillion-dollar annual sales at its peak, although reported revenue varied by year, pricing, international sales, channel inventory and competitive conditions.

Patent 8,633,162 protected only part of that revenue stream. Its economic value came from its role in a layered patent estate covering the commercial product. Generic entry reduced the value of the individual patent and shifted the analysis from complete exclusion to timing of launch, settlement terms and market-share retention.

The most important revenue variables were:

Date of first generic launch.
Number of approved generic suppliers.
Settlement launch rights.
Generic substitution rates.
Price discount to Restasis.
Persistence of branded prescriptions.
Availability of authorized or branded-generic supply.

What licensing deals affect the patent landscape?

The Restasis commercial rights were principally associated with Allergan before Allergan’s acquisition by AbbVie in 2020. The relevant transfer was an acquisition of the broader Allergan business and intellectual-property portfolio, not a stand-alone license of Patent 8,633,162.

Publicly reported Restasis patent disputes centered on ANDA litigation and settlement arrangements with generic manufacturers. Those settlements could determine when a challenger was permitted to launch and whether the launch would be at risk or authorized under agreed terms.

No separate licensing arrangement is necessary to analyze infringement of Patent 8,633,162. Ownership, Orange Book listing, ANDA certification and settlement documents are the controlling commercial records.

How does Patent 8,633,162 compare with generic cyclosporine products?

Issue	Restasis and Patent 8,633,162	Generic cyclosporine ophthalmic emulsion
Active ingredient	Cyclosporine A	Cyclosporine
Strength	0.05%	Typically 0.05%
Dosage form	Ophthalmic emulsion	Ophthalmic emulsion
Reference regimen	Twice daily	Generally labeled to match reference product
Regulatory pathway	NDA	ANDA
Patent relevance	Listed method and formulation estate	Paragraph IV and other certifications
Biosimilar pathway	Not applicable	Not applicable
Main differentiation	Brand, supply, physician familiarity and commercial history	Price, substitution and formulary access

The patent’s claim scope overlaps most closely with a generic that matches the listed composition and twice-daily label. A generic with a materially different formulation may still face other patents, but its exposure to this patent could be reduced.

Key Takeaways

U.S. Patent 8,633,162 is a method-of-use patent covering twice-daily topical treatment of dry eye disease.
The core formulation contains about 0.05% cyclosporin A, about 1.25% castor oil, polysorbate 80, acrylate/C10-30 alkyl acrylate cross-polymer and water.
Narrower claims add glycerine, sodium hydroxide, specific concentrations and a pH of about 7.2 to 7.6.
Claims 11 and 21 address substantially undetectable systemic cyclosporine exposure.
Claims 13-17 add comparative effectiveness, visual-distortion and side-effect limitations.
The patent was associated with the Restasis Orange Book patent estate.
Its scheduled term generally ended in August 2025, subject to the official patent record.
Teva, Mylan and other generic applicants challenged the Restasis patent estate through Paragraph IV certifications and related litigation.
Generic cyclosporine ophthalmic emulsions are small-molecule generics, not biosimilars.
The patent’s greatest commercial value came from its combination with related Restasis formulation and method patents.
A competing product can reduce exposure by changing the excipient system, oil phase, concentration, dosing schedule or pH, but must be assessed against the entire patent estate.

FAQs About U.S. Patent 8,633,162

Does Patent 8,633,162 cover all cyclosporine eye drops?

No. It covers specified methods using a defined emulsion, ingredient combination and twice-daily administration schedule.

Does a 0.05% cyclosporine product automatically infringe?

No. The product must satisfy all limitations of an asserted claim, including the required castor oil, polysorbate 80, acrylate cross-polymer, water, topical administration and twice-daily regimen.

Is Restasis a biologic subject to biosimilar competition?

No. Restasis contains the small-molecule drug cyclosporine and is subject to generic-drug competition through the ANDA framework.

Can a generic avoid the patent by changing its label?

A label change may affect method-of-use infringement, but it does not automatically avoid formulation claims, other listed patents or inducement theories. The full product and patent estate must be reviewed.

What is the main litigation weakness in claims 13-17?

The comparative and performance limitations may require proof of therapeutic equivalence, reduced adverse events, faster emulsion breakdown or reduced vision distortion. Those elements can create claim-construction, evidentiary and reproducibility disputes.

References

AbbVie Inc. (2020). Annual report for the fiscal year ended December 31, 2019. U.S. Securities and Exchange Commission.
Allergan, Inc. (2003). Restasis (cyclosporine ophthalmic emulsion) 0.05% prescribing information. U.S. Food and Drug Administration.
U.S. Food and Drug Administration. (2024). Approved drug products with therapeutic equivalence evaluations. FDA, Center for Drug Evaluation and Research.
U.S. Food and Drug Administration. (2024). Orange Book: Approved drug products with therapeutic equivalence evaluations, NDA 050790. FDA, Center for Drug Evaluation and Research.
U.S. Patent No. 8,633,162. (2014). Methods of treating dry eye disease. United States Patent and Trademark Office.
U.S. Patent and Trademark Office. (2024). Patent term adjustment and patent term information. United States Department of Commerce.

Country	Patent Number	Estimated Expiration	Supplementary Protection Certificate	SPC Country	SPC Expiration
World Intellectual Property Organization (WIPO)	2005032577	⤷ Start Trial
>Country	>Patent Number	>Estimated Expiration	>Supplementary Protection Certificate	>SPC Country	>SPC Expiration

Details for Patent: 8,633,162

Summary for Patent: 8,633,162