Details for Patent: 11,554,241

Summary for Patent: 11,554,241

Title:	Conversion of nitrogen dioxide (NO2) to nitric oxide (NO)
Abstract:	A nitric oxide delivery system, which includes a gas bottle having nitrogen dioxide in air, converts nitrogen dioxide to nitric oxide and employs a surface-active material, such as silica gel, coated with an aqueous solution of antioxidant, such as ascorbic acid. A nitric oxide delivery system may be used to generate therapeutic gas including nitric oxide for use in delivering the therapeutic gas to a mammal.
Inventor(s):	David R. Rounbehler, David H. Fine
Assignee:	Vero Biotech Inc
Application Number:	US15/967,209
Patent Litigation and PTAB cases:	See patent lawsuits and PTAB cases for patent 11,554,241
Patent Claim Types: see list of patent claims	Use; Formulation; Delivery; Device;

United States Patent 11,554,241 Scope and Claims Analysis: Inhaled Nitric Oxide Generated from Nitrogen Dioxide Using Antioxidant-Coated Surface-Active Cartridges

US Patent 11,554,241 is directed to generating therapeutic inhaled nitric oxide (iNO) at ambient temperature from gaseous nitrogen dioxide (NO₂) using one or more cartridge-like “receptacles” that contain surface-active material coated with an antioxidant, with switching-valve-controlled fluid routing between parallel receptacles, optionally with downstream polishing beds (e.g., activated alumina). The independent claim is a method claim with tightly coupled apparatus limitations that shape claim scope, enforceability posture, and design-around paths: the antioxidant-coated, water-retaining/surface-active conversion bed(s) and the valve-based dual-receptacle switching arrangement are central.

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What does US 11,554,241 claim cover (independent claim 1)?

Claim 1 is a method of treating a patient with inhaled nitric oxide using an apparatus that generates therapeutic gas including nitric oxide. The method requires that the iNO is produced by routing a flow of gaseous nitrogen dioxide through at least one conversion receptacle containing (i) an inlet and outlet and (ii) a surface-active material coated with an antioxidant, where the receptacle is configured to convert NO₂ to nitric oxide at ambient temperature.

Core elements of claim 1 (in functional + structural form):

1. Treatment step tied to inhaled nitric oxide

   • “A method of treating a patient with inhaled nitric oxide comprising delivering nitric oxide …”

2. Apparatus includes an NO₂-to-NO conversion system

   • A first receptacle with inlet, outlet, and surface-active material coated with an antioxidant
   • The receptacle is configured to pass a flow of gaseous nitrogen dioxide in contact with the surface-active material to convert NO₂ to nitric oxide at ambient temperature

3. Dual receptacle with antioxidant-coated conversion beds

   • Second receptacle with the same features as the first

4. Switching valve with specific fluid routing role

   • A switching valve where the position creates a fluid connection to the inlet of the first or second receptacle
   • This drives an operational switching scheme between the two conversion beds.

Claim 1 is not a generic iNO delivery claim. It is an iNO delivery method that is expressly constrained by the specific ambient conversion of NO₂ to NO using antioxidant-coated surface-active material and a switching-valve-controlled dual receptacle architecture.

Claim 1 claim-construction pressure points

These are the features that will determine whether a device or process lands inside or outside the claim:

• “surface-active material coated with an antioxidant”

  • The claim requires coated antioxidant on a surface-active material, not merely an antioxidant in a bulk fluid or downstream bed unless it is coated and forms part of the receptacle’s conversion structure.

• “configured to convert … at ambient temperature”

  • The conversion mechanism must operate at ambient temperature. A system that achieves conversion by heating above ambient would argue out-of-scope.

• “pass … contact”

  • The NO₂ must be passed in contact with the surface-active material to effect conversion. Substantially independent conversion paths or minimal contact time may be argued.

• Two receptacles + switching valve

  • Even if a single conversion bed works, the claim’s requirement of both a first and second receptacle plus a valve that switches fluid connection to either inlet creates a design-around lever: single-bed systems without switching between two beds may not meet the full combination.

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How broad is the independent claim’s “apparatus for generating therapeutic gas” scope?

Independence is narrow on the generator architecture but broad on some surrounding details. The claim does not specify:

• exact patient population,
• exact dosing rates,
• exact downstream delivery circuit (other than “delivering nitric oxide to a patient”),
• exact NOₓ composition beyond gaseous nitrogen dioxide as the feed.

But it is restrictive on:

• two conversion receptacles, each with antioxidant-coated surface-active material,
• ambient-temperature conversion,
• switching valve routing.

Method claim vs. product-by-process

This is a method-of-treatment + delivery claim, not a product claim. Still, because it recites a specific apparatus structure inside the method, infringement analysis will track whether the accused method uses a generator with those apparatus limitations during treatment/delivery.

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What do dependent claims 2–11 add (narrowing limitations and design-around impact)?

Below are the incremental constraints introduced by each dependent claim, mapped to likely enforceability and engineering significance.

Claim 2: antioxidant saturation by an aqueous solution

“Surface-active material is saturated with the aqueous solution of the antioxidant.”

• Tightens the claim to a specific antioxidant loading state: saturation with an aqueous solution.
• Design-around: using dry impregnated antioxidant or non-aqueous carriers may avoid.

Claim 3–4: water-retaining substrate; silica gel

Claim 3: substrate retains water
Claim 4: silica gel

• These create an alternate narrower path: if silica gel is used as the water-retaining substrate, it squarely matches.
• Design-around: different water-retaining substrates (e.g., polymer matrices, functionalized aluminas not characterized as silica gel) may avoid those dependent claims, though independent claim 1 may still cover if they still qualify as “surface-active material” coated with antioxidant.

Claim 5: cartridges

“each of the first receptacle and second receptacle comprises cartridges.”

• Cartridges are a common engineering choice. This dependent claim narrows to cartridge form factor but does not necessarily narrow the underlying conversion chemistry already claimed in independent claim 1.

Claim 6: antioxidant is ascorbic acid

• Narrows antioxidant identity to ascorbic acid.

Claim 7: antioxidant is tocopherol

• Narrows antioxidant identity to tocopherol.

Key practical consequence: independent claim 1 is not limited to a specific antioxidant identity, while dependent claims provide fall-back claim coverage for prominent antioxidants (ascorbic acid and tocopherol).

Claim 8: optional third receptacle with activated alumina polishing

“third receptacle … including activated alumina … inlet … configured to receive flow from the first or second receptacle … outlet … through activated alumina.”

• Adds an optional downstream bed.
• Design-around: omit activated alumina and/or alter polishing step. Claim 8 is dependent, so the main coverage remains in claim 1 without the third bed.

Claim 9: screen and glass wool adjacent to inlet and outlet

• Adds specific internal support/filtration media adjacent to both inlet and outlet.
• Design-around: different support media (sintered metal, ceramic foam) could avoid claim 9 without affecting claim 1.

Claim 10: nitrogen source connected to both outlets

“nitrogen source fluidly connected to the first receptacle outlet and to the second receptacle outlet.”

• This suggests an inert carrier or diluent gas routing for NO₂/NOₓ conversion and/or mixing.
• Design-around: if the system uses air/other carrier rather than nitrogen, or if nitrogen is connected differently, claim 10 can be evaded.

Claim 11: second switching valve fluidly connected to second receptacle inlet

• Adds an additional switching valve arrangement beyond the valve in claim 1.
• Likely to be relevant if the architecture includes sequential routing or controlled feed metering.

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What is the implied conversion chemistry and system architecture from the claim language?

The claims imply a system where NO₂ is converted to NO at ambient temperature by contacting NO₂ with a surface-active material bearing an antioxidant that appears to be delivered or held as an aqueous-saturated phase (dependent claim 2) on a water-retaining substrate (dependent claim 3), with explicit examples including silica gel as substrate (claim 4) and ascorbic acid or tocopherol as antioxidant (claims 6–7).

That creates a coherent architecture:

• Parallel conversion beds (first and second receptacles)
• Switching valve selects which bed receives NO₂ flow
• Optional polishing bed (activated alumina) downstream
• Optional nitrogen carrier/diluent connected to outlets
• Optional cartridge/support media (screen/glass wool)

From an IP scope standpoint, the combination of ambient conversion + antioxidant-coated surface-active/water-retaining material is likely the novelty driver.

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What patents protect this technology around US 11,554,241 (how to map a patent landscape)?

Insufficient information in the prompt prevents a complete, accurate cross-patent landscape mapping. A defensible “landscape” requires at least:

• the patent’s bibliographic record (inventor/applicant),
• the full patent specification (to identify additional claim sets and priority filings),
• prosecution history, and
• the cited references/related families (continuations/divisionals, PCT family members, and forward citations).

Per the operating constraints, no partial or speculative landscape can be produced.

Accordingly, this analysis restricts to scope and claim architecture of US 11,554,241 as provided.

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How do the claims affect infringement risk and design-around options?

Most direct infringement footprint

A competitor method using inhaled NO delivery will likely be most exposed if it uses:

• NO₂ feed
• dual conversion receptacles
• surface-active material coated with antioxidant
• ambient-temperature conversion
• valve switching to connect NO₂ to one inlet at a time.

High-leverage design-arounds

Because claim 1 requires multiple elements in combination, the most straightforward avoidances are:

1. Single conversion bed system

   • Remove second receptacle and/or eliminate valve switching between two receptacles.

2. No antioxidant-coated surface-active conversion bed

   • Use a different conversion approach (e.g., catalytic materials without antioxidant coating; separate antioxidant handling not as “coated with”).

3. Non-ambient conversion

   • Operate conversion by heating above ambient, arguing the “ambient temperature” limitation.

4. Different antioxidant incorporation state

   • For dependent claims: avoid aqueous saturation (claim 2), avoid water-retaining substrate design (claim 3), avoid silica gel (claim 4), and avoid ascorbic acid/tocopherol (claims 6–7).

5. Skip activated alumina polishing

   • Avoid claim 8-specific third bed.

6. Different internal media and nitrogen connection

   • Avoid claim 9 screen/glass wool configuration.
   • Avoid claim 10 nitrogen source connectivity as specified.
   • Avoid claim 11 additional switching valve arrangement.

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How strong is US 11,554,241 likely to be on claim scope (practical enforcement view)?

Even without bibliographic data, the claim language suggests:

• Strength on architecture: two receptacles + switching valve + antioxidant-coated surface-active ambient NO₂-to-NO conversion is specific enough to capture closely aligned systems.
• Vulnerability to broad prior art on NO₂-to-NO conversion: the broader the art that already disclosed ambient NO₂ conversion, the more likely validity challenges focus on the antioxidant-coated surface-active/water retention and dual-switch architecture.

But strength is still claim-dependent: dependent claims (ascorbic acid, tocopherol, silica gel, activated alumina polishing, cartridges) provide fallback coverage if the independent claim face art is limited.

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Key Takeaways

• US 11,554,241 claim 1 is a method-of-treating-with-iNO claim constrained by a specific generator architecture: ambient NO₂-to-NO conversion via antioxidant-coated surface-active receptacles, using two parallel receptacles and a switching valve selecting which inlet is fluidly connected.
• Dependent claims tighten practical engineering features (aqueous saturation; water-retaining substrates like silica gel; specific antioxidants such as ascorbic acid and tocopherol; cartridge form; activated alumina polishing; internal screens/glass wool; nitrogen source routing; additional valve logic).
• Design-around is feasible by breaking at least one of the combination-critical elements in claim 1 (dual receptacles + switching, antioxidant-coated surface-active ambient conversion, or conversion temperature basis).
• A complete patent landscape cannot be produced from the provided input, because the patent record and related family/citation data are not included.

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FAQs

1) Does US 11,554,241 cover nitric oxide generation from other nitrogen oxides besides NO₂?
Claim 1 requires converting a flow of gaseous nitrogen dioxide (NO₂) to nitric oxide, so coverage is tied to NO₂ as the feed.

2) Is the antioxidant required to be ascorbic acid or tocopherol under claim 1?
No. Claim 1 requires an antioxidant generically; ascorbic acid (claim 6) and tocopherol (claim 7) apply to narrower dependent positions.

3) Can a system with two receptacles be outside the claim if it does not use “surface-active material” coated with an antioxidant?
Yes. The “surface-active material coated with an antioxidant” limitation is built into claim 1, so absence of that feature should avoid meeting the claim.

4) Do activated alumina and nitrogen source features matter for infringement?
Not for claim 1. Activated alumina (claim 8) and the nitrogen source routing (claim 10) are dependent limitations.

5) What is the most sensitive claim element for designing a workaround?
The combination of ambient NO₂-to-NO conversion plus antioxidant-coated surface-active receptacles plus dual receptacle switching is the highest-sensitivity set for avoiding claim 1.

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References (APA)

1. United States Patent No. 11,554,241. Claims provided in prompt.

Drugs Protected by US Patent 11,554,241

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

International Family Members for US Patent 11,554,241

Country	Patent Number	Estimated Expiration	Supplementary Protection Certificate	SPC Country	SPC Expiration
Australia	2005277397
Canada	2576957
European Patent Office	1789119
European Patent Office	2724742
Japan	2008510675
Japan	2012179365
Japan	5421530