US Patent 9,114,168: Moxifloxacin Ophthalmic Composition Claims, Scope and Patent Landscape

US Patent 9,114,168 protects a narrowly defined aqueous moxifloxacin ophthalmic formulation associated with the Moxeza-type product profile. The claims require a specific combination of moxifloxacin, sodium chloride, a polyether alcohol surfactant, borate, polyol, xanthan gum, water, and low turbidity. The strongest protection is in claims 8 and 11, which impose tighter concentration ranges, pH limits, and, for claim 11, osmolality requirements.

The patent does not broadly cover moxifloxacin ophthalmic solutions. A competing product can potentially avoid infringement by changing the xanthan gum concentration, sodium chloride-to-moxifloxacin ratio, surfactant identity or concentration, borate-polyol level, pH, turbidity, or osmolality.

What patent is US 9,114,168 and who owns it?

US Patent 9,114,168 is titled "Moxifloxacin ophthalmic compositions." The patent was issued on August 25, 2015, and is associated with Alcon Research, Ltd., the Alcon entity responsible for research and development of ophthalmic products.

Item	Details
Patent	US 9,114,168 B2
Title	Moxifloxacin ophthalmic compositions
Issue date	August 25, 2015
Technology	Aqueous ophthalmic moxifloxacin formulation
Key excipients	Sodium chloride, polyether alcohol surfactant, borate, polyol, xanthan gum
Key performance limitation	Turbidity below 13 NTU or below 10 NTU
Narrowest claim	Claim 11
Commercial relevance	Moxeza-type moxifloxacin ophthalmic formulation
Likely patent term	Extends into the late 2020s, subject to the patent file history, PTA, terminal disclaimers, and applicable Orange Book listing

The claims supplied are composition claims. They do not claim a method of treating bacterial conjunctivitis, a method of administering moxifloxacin, a manufacturing process, or a particular disease indication.

What does US 9,114,168 protect?

The patent protects a formulation architecture rather than the moxifloxacin molecule itself. Each independent claim requires moxifloxacin at a concentration of at least 0.4% w/v but below 1.0% w/v.

The core formulation has six technical components:

Moxifloxacin.
Sodium chloride at a controlled ratio to moxifloxacin.
A polyether alcohol surfactant.
A borate and polyol system.
Xanthan gum.
Water.

The composition must also satisfy a turbidity limitation. Turbidity is a significant claim element because a product containing all listed ingredients may still fall outside the claim if its turbidity is 13 NTU or higher for claim 1, or 10 NTU or higher for claims 6, 8, and 11.

Claim element summary

Claim	Independent or dependent	Principal limitations
1	Independent	0.4% to <1.0% moxifloxacin; sodium chloride:moxifloxacin ratio 1.0-1.7; 0.02% to <0.1% polyether alcohol surfactant; 0.2% to <1.0% combined borate and polyol; 0.3% to <1.2% xanthan gum; turbidity below 13 NTU
2	Dependent	Borate plus polyol at 0.5% to <0.7%
3	Dependent	Surfactant at 0.04% to <0.1%
4	Dependent	Packaged in an eye-drop container
5	Dependent	Sorbitol and boric acid
6	Dependent	Turbidity below 10 NTU
7	Dependent	pH 6.4-7.5
8	Independent	Narrower ratio, surfactant, excipient, xanthan gum, turbidity, and pH requirements
9	Dependent	Eye-drop container
10	Dependent	Sorbitol and boric acid
11	Independent	Claim 8 formulation plus "consisting essentially of" language and osmolality of 200-400 mOsm/kg

How broad is claim 1 of US 9,114,168?

Claim 1 is broad relative to claims 8 and 11, but it remains technically narrow. It uses "comprising," which generally permits the presence of additional ingredients, provided the accused product still contains every required limitation.

A product is potentially within claim 1 if it has:

Moxifloxacin at 0.4% to below 1.0% w/v.
Sodium chloride at a weight/volume ratio to moxifloxacin of 1.0 to 1.7.
A polyether alcohol surfactant at 0.02% to below 0.1% w/v.
Total borate and polyol at 0.2% to below 1.0% w/v.
Xanthan gum at 0.3% to below 1.2% w/v.
Water.
Turbidity below 13 NTU.

The range boundaries matter. The claim excludes:

Moxifloxacin concentrations below 0.4% or at 1.0% or higher.
Surfactant concentrations at 0.1% or higher.
Xanthan gum concentrations at 1.2% or higher.
A sodium chloride-to-moxifloxacin ratio below 1.0 or above 1.7.
Turbidity of 13 NTU or higher.

The use of "less than" creates a strict upper boundary. A formulation at exactly 1.0% moxifloxacin, 0.1% surfactant, or 1.2% xanthan gum does not literally satisfy those limitations, although infringement analysis can also involve the doctrine of equivalents.

How do claims 8 and 11 narrow the patent protection?

Claims 8 and 11 define the commercially important center of the patent estate.

Claim 8

Claim 8 requires:

Moxifloxacin at 0.4% to below 1.0% w/v.
Sodium chloride-to-moxifloxacin ratio of 1.1 to 1.4.
Alkyl aryl polyether alcohol surfactant at 0.04% to below 0.07% w/v.
Combined borate and polyol at 0.5% to below 1.0% w/v.
Xanthan gum at 0.6% to below 0.75% w/v.
Turbidity below 10 NTU.
pH of 6.7 to 7.5.

This claim is substantially narrower than claim 1. It does not merely require a polyether alcohol surfactant. It requires the narrower category of an alkyl aryl polyether alcohol. A formulation using a different class of nonionic surfactant may avoid claim 8 while remaining potentially relevant to claim 1.

Claim 11

Claim 11 uses "consisting essentially of," which limits the permissible additional ingredients more substantially than "comprising." The phrase generally allows components that do not materially affect the basic and novel characteristics of the formulation, but it creates a more fact-intensive infringement question for products containing additional excipients.

Claim 11 adds:

The narrower claim 8 formulation ranges.
An osmolality of 200 to 400 mOsm/kg.
The same below-10-NTU turbidity requirement.
The same pH range of 6.7 to 7.5.

Claim 11 is likely the most commercially targeted claim because it captures a physiologically suitable ophthalmic formulation while imposing a defined clarity and osmolality profile.

What formulations are specifically protected by US 9,114,168?

The claim language identifies a formulation profile consistent with a moxifloxacin ophthalmic suspension or solution containing xanthan gum as a viscosity-enhancing polymer and a surfactant to support physical stability and clarity.

Protected ingredient relationships

The patent is particularly sensitive to relationships among the ingredients:

The sodium chloride limitation is ratio-based, not merely concentration-based.
The borate and polyol are measured as a combined total.
The surfactant is defined by both concentration and chemical class.
Xanthan gum is defined by a narrow concentration window in claims 8 and 11.
Turbidity and pH are express claim limitations, not merely product-quality characteristics.

The ratio limitation means that a generic applicant cannot evaluate sodium chloride in isolation. For example, if the formulation contains 0.5% moxifloxacin, the claimed sodium chloride range is approximately:

Claim	Sodium chloride range when moxifloxacin is 0.5%
Claim 1	0.50%-0.85% w/v
Claims 8 and 11	0.55%-0.70% w/v

The exact result depends on whether the claim's moxifloxacin concentration is calculated as moxifloxacin base or moxifloxacin hydrochloride equivalent. That issue can affect both literal scope and regulatory product comparisons.

Does Moxeza fall within the claimed formulation profile?

Moxeza is an Alcon moxifloxacin ophthalmic product containing 0.5% moxifloxacin hydrochloride and xanthan gum. Its labeled inactive ingredients include boric acid, sorbitol, sodium chloride, tyloxapol, and xanthan gum. The product has a near-neutral pH and an ophthalmic delivery format. These characteristics correspond closely to the elements recited in claims 8 and 11. [2]

Moxeza-type characteristic	Relevance to US 9,114,168
0.5% moxifloxacin	Within the claimed 0.4% to <1.0% range
Sodium chloride	Relevant to the claimed sodium chloride-to-moxifloxacin ratio
Tyloxapol	An alkyl aryl polyether alcohol-type surfactant relevant to claims 8 and 11
Boric acid	Expressly identified in dependent claims 5 and 10
Sorbitol	Expressly identified in dependent claims 5 and 10
Xanthan gum	Required in all independent claims
Ophthalmic container	Covered by claims 4 and 9
Near-neutral pH	Potentially within the pH limitations
Controlled clarity	Relevant to the turbidity limitations
Controlled osmolality	Relevant to claim 11

The product label does not, by itself, establish infringement. A claim analysis would require the marketed formulation's exact concentrations, measured turbidity, pH, osmolality, and the chemical identity of the surfactant. The label does establish that Moxeza was designed around the same formulation variables recited in the patent. [2]

What is the Orange Book status of US 9,114,168?

Orange Book relevance depends on whether the patent was submitted for listing against the applicable Moxeza new drug application and whether FDA accepted the submission. A patent number's existence does not by itself establish current Orange Book listing status.

For a listed drug patent, the patent may affect an ANDA applicant through a Paragraph IV certification under the Hatch-Waxman framework. The relevant regulatory questions are:

Whether US 9,114,168 is listed against the Moxeza NDA.
Whether the listed patent is identified as a formulation patent.
Whether the patent's expiration date in the Orange Book includes patent-term adjustment.
Whether the NDA holder has submitted a delisting request.
Whether a generic applicant has filed a Paragraph IV certification.

FDA's Orange Book is the controlling public source for current listed-patent status and expiration data. [1] The patent's claims alone cannot establish that status.

When does US 9,114,168 lose exclusivity?

The patent's statutory term is generally 20 years from the relevant earliest nonprovisional or PCT filing date, subject to patent-term adjustment and other record-specific modifications under 35 U.S.C. § 154. [3]

The patent issued in 2015, but the issue date does not determine expiration. A patent issued after the relevant filing date can remain enforceable until the end of its statutory term. For this patent family, the commercial risk period is centered in the late 2020s rather than at the 2015 issue date.

Regulatory exclusivity is separate from patent exclusivity:

Exclusivity type	Relevance
New chemical entity exclusivity	Moxifloxacin's molecule-level exclusivity is not the principal issue for this formulation patent
NDA exclusivity	Depends on the applicable Moxeza NDA and FDA exclusivity record
Formulation patent exclusivity	The principal protection created by US 9,114,168
Patent-term adjustment	May extend the patent beyond a simple 20-year calculation
Pediatric exclusivity	Could add six months if granted for the relevant product and time period
Orange Book expiration	Must be checked against the current FDA listing

A generic applicant may be able to obtain approval before patent expiration through a Paragraph IV challenge, a non-infringement position, invalidity position, or a formulation design-around.

What Paragraph IV challenges could target this patent?

A Paragraph IV challenge would likely focus on one or more of four theories:

The proposed formulation does not satisfy one or more numerical limitations.
The surfactant is outside the claimed chemical class.
The proposed product has turbidity, pH, or osmolality outside the claimed range.
One or more claims are invalid for anticipation or obviousness.

Likely non-infringement positions

A generic applicant could design around the claims by using:

A surfactant that is not a polyether alcohol.
An alkyl polyether, poloxamer, polysorbate, or other surfactant outside the claimed alkyl aryl polyether alcohol category.
Xanthan gum below 0.3% or at least 1.2%.
A sodium chloride-to-moxifloxacin ratio below 1.0 or outside 1.1 to 1.4.
A pH below 6.4 or above 7.5.
Turbidity at or above the claimed threshold.
A formulation without xanthan gum.

A deliberate turbidity increase would not necessarily be commercially attractive because ophthalmic products require acceptable visual quality, physical stability, and patient tolerability. The more practical design-around routes are changing the viscosity agent, surfactant system, or salt balance.

Likely validity positions

The most important prior-art questions concern whether earlier moxifloxacin ophthalmic formulations disclosed the claimed combination of:

Xanthan gum.
Tyloxapol or a structurally similar surfactant.
Boric acid and sorbitol.
A specified sodium chloride ratio.
Low turbidity.
A pH of 6.7 to 7.5.
An osmolality of 200 to 400 mOsm/kg.

A reference that discloses the individual ingredients but not the claimed numerical combination may be insufficient for anticipation. It may still be relevant to obviousness, particularly if it teaches moxifloxacin ophthalmic formulations, xanthan gum for viscosity control, and conventional tonicity or buffering systems.

What patent litigation affects US 9,114,168?

The patent number and claim text do not establish a litigation outcome. Litigation exposure would need to be evaluated through district court dockets, Federal Circuit decisions, PTAB records, FDA litigation notifications, and any settlement agreements.

For a generic moxifloxacin ophthalmic applicant, the relevant litigation trigger would be a Paragraph IV notice to the NDA holder and patent owner. Under 21 U.S.C. § 355(j)(5)(B)(iii), a timely patent infringement action can create a 30-month stay of ANDA approval, subject to statutory exceptions and court action. [4]

A settlement agreement could include:

A licensed entry date.
A covenant not to sue.
A formulation restriction.
An authorized generic arrangement.
A payment or commercial supply arrangement.
A clause covering continuation, divisional, or reissue patents.

No settlement terms should be inferred from the patent claims. A continuation patent can materially change the risk profile even after a product avoids the issued claims.

How strong is the patent estate for Moxeza-type products?

The estate is strongest against products that copy the complete formulation profile. It is weaker against products that use a different viscosity enhancer or surfactant system.

Risk factor	Assessment
Active ingredient protection	Weak at the molecule level because moxifloxacin is an established active ingredient
Formulation specificity	Strong where all numerical ranges overlap
Surfactant limitation	Creates a meaningful design-around opportunity
Xanthan gum limitation	Strong against close copies; avoidable through polymer substitution
Turbidity limitation	Potentially difficult to prove without batch testing
pH limitation	Easy to measure and potentially easy to design around
Osmolality limitation	Relevant primarily to claim 11
"Comprising" claims	Broadens claims 1 and 8 to products with additional excipients
"Consisting essentially of" claim	Creates a narrower but more complex claim 11 analysis
Manufacturing barrier	Moderate; reproducing low turbidity and stable viscosity may require formulation development
Generic substitution risk	High if a generic can use a non-infringing xanthan-free or alternative-surfactant formulation

The patent's commercial value comes from the combination of formulation performance and claim density. The formulation may be difficult to duplicate precisely while preserving clarity, viscosity, comfort, and preservative performance. That technical difficulty does not eliminate legal design-around options.

How does US 9,114,168 compare with other moxifloxacin ophthalmic products?

The principal comparison is between a conventional moxifloxacin ophthalmic solution such as Vigamox and the xanthan gum-containing Moxeza formulation.

Product type	Moxifloxacin	Xanthan gum	Surfactant profile	Patent exposure under US 9,114,168
Conventional 0.5% moxifloxacin solution	0.5%	Typically absent	Different or limited excipient system	May avoid the claims
Moxeza-type formulation	0.5%	Present	Tyloxapol-type polyether alcohol	Higher potential exposure
Generic design-around	0.5% or other claimed level	Alternative polymer or absent	Non-claimed surfactant	Potentially lower exposure
Non-moxifloxacin antibiotic	Different active	Variable	Variable	Outside the claims

US 9,114,168 does not cover every generic moxifloxacin ophthalmic product. The highest risk is from a product that uses the same excipient architecture and falls inside the numerical ranges.

What manufacturing and intellectual-property barriers exist?

Manufacturing barriers are concentrated in physical stability rather than synthesis of moxifloxacin. A manufacturer must control:

Xanthan gum hydration and dispersion.
Surfactant compatibility.
Borate-polyol interactions.
Sodium chloride concentration.
Moxifloxacin salt form and assay basis.
pH adjustment.
Turbidity and particulate control.
Osmolality.
Container-closure compatibility.

A product can avoid literal infringement but still require substantial development work to achieve comparable shelf life and ophthalmic tolerability. Conversely, the patent claims do not appear to cover every process used to manufacture the formulation. A manufacturer could use a different order of addition, mixing method, sterilization approach, or packaging process unless separate process or container patents apply.

What generic launch scenarios exist for this patent?

Scenario 1: Formulation design-around

A generic applicant develops a moxifloxacin product without xanthan gum or without the claimed surfactant class. This is the clearest route to reduce infringement risk, but it may produce a product more similar to conventional moxifloxacin ophthalmic solutions than to Moxeza.

Scenario 2: Paragraph IV challenge

The applicant certifies that the patent is invalid, unenforceable, or will not be infringed. The NDA holder may sue within the statutory period, potentially delaying approval through the 30-month stay.

Scenario 3: Paragraph III certification

The applicant accepts the patent and seeks approval after the listed patent expiration date. This reduces litigation exposure but delays commercial entry.

Scenario 4: Authorized generic or settlement entry

The innovator may permit entry on an agreed date or supply an authorized generic. The commercial effect depends on launch timing, substitution rules, pricing, and the number of competing ANDAs.

Scenario 5: Non-infringing conventional solution

A generic applicant relies on a formulation materially different from Moxeza but comparable to conventional moxifloxacin ophthalmic products. This could reduce exposure to the patent while increasing differentiation from the branded formulation.

Key Takeaways

US 9,114,168 is a formulation patent, not a broad moxifloxacin composition patent.
The claims require xanthan gum, a polyether alcohol surfactant, borate, polyol, sodium chloride, water, and specified physical characteristics.
Claim 1 is the broadest independent claim, but claims 8 and 11 target a much narrower commercial formulation profile.
Claims 8 and 11 are most relevant to a Moxeza-type product containing 0.5% moxifloxacin, tyloxapol, boric acid, sorbitol, sodium chloride, and xanthan gum.
The principal design-around options are changing the surfactant, replacing xanthan gum, moving outside the salt ratio, or adjusting pH and other measurable parameters.
Claim 11 is narrower because it uses "consisting essentially of" and adds an osmolality range.
Orange Book listing, current expiration, Paragraph IV activity, and litigation status must be determined from FDA, USPTO, court, and PTAB records rather than from the claim language alone.
The strongest commercial risk is a close formulation copy. The strongest generic opportunity is a conventional or reformulated moxifloxacin ophthalmic product outside the claimed excipient architecture.

FAQs

Is US 9,114,168 a patent on Moxeza itself?

No. It is a patent on specified aqueous moxifloxacin ophthalmic compositions. The patent does not cover every product sold under the Moxeza name or every moxifloxacin ophthalmic formulation.

Does a product infringe if it contains 0.5% moxifloxacin and xanthan gum?

Not necessarily. The product must also satisfy the applicable sodium chloride ratio, surfactant identity and concentration, borate-polyol concentration, turbidity, pH, and, for claim 11, osmolality limitations.

Can a generic use tyloxapol without infringing US 9,114,168?

Tyloxapol may be relevant to the alkyl aryl polyether alcohol limitation in claims 8 and 11. Use of tyloxapol does not alone determine infringement; the complete formulation and all numerical limitations must be compared.

Does changing the pH avoid the patent?

It may avoid claims 7, 8, and 11 if the product falls outside their pH ranges. It would not necessarily avoid claim 1 unless the product also falls outside claim 1's other limitations, because claim 1 has no pH limitation.

Does US 9,114,168 cover a formulation with polyethylene glycol instead of xanthan gum?

A formulation without xanthan gum would not literally satisfy the xanthan gum limitation in claims 1, 8, or 11. Other patents, regulatory requirements, or the doctrine of equivalents could still affect the overall risk analysis.

References

U.S. Food and Drug Administration. (2024). Approved drug products with therapeutic equivalence evaluations: Orange Book. https://www.fda.gov/drugsatfda
U.S. Food and Drug Administration. (n.d.). Moxeza (moxifloxacin hydrochloride ophthalmic solution) prescribing information.
United States Patent and Trademark Office. (2015). U.S. Patent No. 9,114,168 B2, Moxifloxacin ophthalmic compositions.
21 U.S.C. § 355(j)(5)(B)(iii). Abbreviated new drug applications and patent certifications.

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Patented / Exclusive Use	Submissiondate
Harrow Eye	MOXEZA	moxifloxacin hydrochloride	SOLUTION/DROPS;OPHTHALMIC	022428-001	Nov 19, 2010		DISCN	Yes	No	⤷ Start Trial	⤷ Start Trial	Y				⤷ Start Trial
>Applicant	>Tradename	>Generic Name	>Dosage	>NDA	>Approval Date	>TE	>Type	>RLD	>RS	>Patent No.	>Patent Expiration	>Product	>Substance	>Delist Req.	>Patented / Exclusive Use	>Submissiondate

Country	Patent Number	Estimated Expiration	Supplementary Protection Certificate	SPC Country	SPC Expiration
Argentina	072071	⤷ Start Trial
Australia	2009257778	⤷ Start Trial
Brazil	PI0914971	⤷ Start Trial
Canada	2726616	⤷ Start Trial
Chile	2009001379	⤷ Start Trial
China	102056590	⤷ Start Trial
China	103550141	⤷ Start Trial
>Country	>Patent Number	>Estimated Expiration	>Supplementary Protection Certificate	>SPC Country	>SPC Expiration

Details for Patent: 9,114,168

Which drugs does patent 9,114,168 protect, and when does it expire?

Summary for Patent: 9,114,168