United States Patent 8,829,054 (Esmolol HCl co-solvent sterile premix in non-PVC flexible containers): claim scope, infringement-relevant elements, and US patent landscape
US Drug Patent 8,829,054 covers a tightly specified sterile, buffered esmolol hydrochloride intravenous co-solvent premixed solution packaged in a non-PVC flexible plastic container with defined physicochemical ranges and terminal heat-moist sterilization (autoclave/heat-moist). The estate is claim-dense around (1) formulation composition and pH, (2) specific co-solvent systems (ethyl alcohol plus propylene glycol or glycerin), (3) container material structure and terminal-sterilization suitability, and (4) performance outcomes after autoclaving (minimal esmolol loss and limited related ester formation). The independent claim set also reaches (i) preparation methods and (ii) bradycardia/hypotension control during human computerized cardiac tomography (CT) via administration.
What is US 8,829,054, and what parts of the claims matter for infringement?
Core patented subject matter (independent claim 1).
A co-solvent sterile premixed pharmaceutical product stored in a non-PVC flexible plastic container where the solution has:
- pH 4.5 to 5.5
- esmolol HCl: 5 to 40 mg/mL (methyl-3-[4-(2-hydroxy-3-isopropylamino)propoxy]phenylpropionate hydrochloride)
- buffering agent maintaining pH 4.5 to 5.5
- 0.1% to 3 w/v% ethyl alcohol
- 0.1% to 3 w/v% of one of propylene glycol or glycerin
- sealed container and heat-moist sterilized for time sufficient to sterilize
Infringement relevance checklist.
To land within claim 1, an accused product must satisfy every constraint, not just the active:
- Sterile premixed esmolol HCl solution (not a kit or two-part system)
- Solution pH 4.5–5.5 using an in-claim buffering system
- Co-solvent system within ranges:
- ethyl alcohol 0.1–3 w/v%
- propylene glycol or glycerin 0.1–3 w/v%
- Non-PVC flexible container with sealed packaging
- Terminal heat-moist sterilization (autoclave/heat-moist) of the sealed product
- The claim reads on the manufactured state (“stored,” “contained,” “heat-moist sterilized”), so process and resultant formulation state both matter.
How broad is the formulation claim scope (claims 1, 5–11)?
Is the esmolol concentration broad or narrow (claim 1 and claim 8)?
- Claim 1: 5 to 40 mg/mL esmolol HCl.
- Claim 8 narrows further: 10 to 30 mg/mL.
If a generic or competitor targets outside 5–40 mg/mL, it avoids claim 1. If within 5–40 mg/mL, it still may avoid dependent claims 8 and others, but claim 1 remains a risk.
Does the buffer system constrain infringement (claims 5–7)?
- Claim 5: buffering agent is at least one of acetate, tartrate, malate, furmarate.
- Claim 6: sodium acetate
- Claim 7: sodium tartrate
This matters because claim 1 requires a buffering agent maintaining pH, but the dependent claims fence the buffer species. If an accused product uses buffers outside those enumerated families, it may avoid dependent claims 5–7 while still potentially reading on claim 1 (since claim 1 only requires a buffering agent generally, not those specific salts).
How tight are the co-solvent ranges (claims 1, 9–10)?
- Ethyl alcohol: 0.1% to 3 w/v%
- Propylene glycol or glycerin: 0.1% to 3 w/v%
Dependent claim 9 specifies propylene glycol; claim 10 specifies glycerin.
Practical take: a formulation with ethyl alcohol below 0.1% or above 3% is outside. Same for the second co-solvent. This gives formulation designers clear design-around levers, but the pH target and sterilization constraints remain.
What performance outcomes tighten claim 11?
Claim 11 adds additional, technical performance limitations:
- <2% decrease in esmolol concentration after autoclaving
- related esmolol esters < about 0.5%
- co-solvent composition between 0.15% to 5% (note this appears broader than claim 1’s 0.1–3%)
- storage in non-PVC flexible container where the inner-most layer contacting the solution comprises a copolymer of ethylene and vinyl acetate (EVA).
This is a key scope hinge: it couples container-polymer contact layer and chemical stability outcomes after terminal sterilization. Many competitors may use non-PVC films but not an EVA inner layer, or may have different ester profiles after sterilization.
How broad is the container scope (claims 2–4 and claim 11)?
Is “non-PVC flexible plastic container” the main novelty?
Claim 1 requires a non-PVC flexible plastic container. That’s necessary but still broad. Claims 2–4 add structural and material specifics, tightening the scope for some embodiments.
What container architecture is claimed (claim 2)?
Claim 2 specifies:
- 3–7 multi-layer, polyolefin-based, co-extruded film
- non-PVC, latex-free, plasticizer-free
- tubing ports made of a two-layer material suitable for terminal sterilization
This narrows claim coverage to certain film architectures and port constructions. If an accused product uses a different non-PVC packaging technology (single-layer film, different polymer families, or different port material), it may fall outside dependent claims but still potentially read on claim 1 if it still uses a non-PVC flexible container and the specified formulation and sterilization.
Which polymer families are named (claim 3)?
Claim 3 lists:
- polypropylene
- cycloolefin
- polyethylene
- copolymerized ethylene vinyl acetate (EVA)
This is both constraining and instructive: the claim is written to include several common non-PVC IV container materials. It also primes EVA relevance, which becomes explicit again in claim 11 as the inner-most layer copolymer contacting the solution.
Are tubing ports and closures independently claimed (claim 4)?
Claim 4 covers modified tubing ports and closure systems made of a material suitable for terminal sterilization.
This can matter because container vendors often sell components where ports/closures differ from the film. Even if the film is right, mismatched port/closure materials can create non-infringing configurations relative to claim 2/4.
What method claims add to the reach (claims 13–18)?
Claim 13 and following claims cover how the product is made:
- prepare composition with the same formulation constraints
- add to non-PPVC flexible container
- seal
- heat-moist sterilize to form the sterile product
Claims 14–15 add:
- heat-moist sterilization is autoclaving
- temperature 110–130°C
- time 7–60 minutes
Claims 16–18 include additional method variants that are still tethered to non-PVC flexible container and the same composition setup, then sealing and sterilization. Method claims increase litigation leverage because they can reach a manufacturer’s internal process even when final-stage packaging might be sourced differently.
How is the clinical use framed (claim 12)?
Claim 12: method controlling bradycardia and/or hypotension in diagnosis of cardiac conditions in humans using computerized cardiac tomography (CT) by administering an effective amount of the pharmaceutical product of claim 1.
Key scope point: this is not just “esmolol for bradycardia.” It ties the indication to CT-based diagnosis and the specific product of claim 1. A challenge or design-around might focus on different diagnostic imaging modalities, different indication framing, or different product variants not meeting claim 1.
Timeline and expiration mechanics (what can be inferred from claims alone?)
No priority date, filing date, patent term adjustment, or maintenance status is provided in the prompt, so an exact US expiration date and exclusivity end cannot be produced from the claim text. The only definitive conclusion possible from scope alone is that the patent’s enforceability for filing-date-based term is tied to the application’s priority and prosecution history, which are not supplied.
US patent landscape for esmolol IV formulations and container technology: where 8,829,054 fits
Because no bibliographic identifiers, assignee, CPC classes, family members, or listed citations are provided, only a scope-based landscape mapping is possible from the claim structure. The landscape divides into four competitive IP zones that typically cluster around this kind of invention:
1) Formulation patents: pH window + co-solvent system + sterilization stability
8,829,054 is unusually specific: it requires
- pH 4.5–5.5
- ethyl alcohol with either propylene glycol or glycerin
- specific concentrations and ranges
- heat-moist sterilization in the sealed non-PVC container
- controlled related ester formation (<0.5% in claim 11) and esmolol loss (<2%)
Competitors often litigate around:
- whether alternative buffers outside acetate/tartrate/malate/fumarate still meet claim 1 (buffer function only) or only avoid dependents (buffer identity)
- whether an alternative co-solvent package omits ethyl alcohol or changes concentrations
- whether different terminal sterilization protocols change ester formation and degradation pathways, potentially avoiding claim 11’s performance metrics.
2) Packaging/container patents: non-PVC film, multilayer co-extruded films, and EVA contact layers
Claim 2–4 focus on the container-film system; claim 11 adds EVA inner layer contact.
In the real market, this often overlaps with container-platform IP (film structures, port/closure designs). That creates a two-layer IP landscape:
- “drug product” patents like 8,829,054 that claim the combination of drug solution + particular container architecture + terminal sterilization
- “container platform” patents that claim film structure independent of the drug.
A product supplier may have rights to container platforms but not to the drug formulation combination, or vice versa, which affects freedom-to-operate analysis.
3) Process patents: terminal sterilization parameters in the sealed non-PVC system
Method claims 13–18 can be used even if a competitor sources finished containers or sterilizes differently. The claimed parameter ranges (110–130°C and 7–60 minutes for autoclaving in dependents) create a measurable divergence path:
- sterile processing at different times/temps, or using non-heat-moist sterilization, can avoid the method dependents while potentially leaving product claim 1 exposure if the final state still corresponds.
4) Use patents: CT-bradycardia/hypotension method tied to the product
Claim 12 ties the medical method to administration of the claimed product. This is narrower than generic “esmolol use” but can still matter if competitors market for CT-based diagnostic protocols and the product matches claim 1.
Which design-arounds are most straightforward based on claim structure?
Formulation switches that likely avoid claim 1
- Remove ethyl alcohol (eliminate 0.1–3% w/v range).
- Use propylene glycol/glycerin outside 0.1–3% w/v.
- Move pH outside 4.5–5.5 (even with a buffer).
- Use esmolol concentration outside 5–40 mg/mL.
Packaging design changes that likely avoid dependents (not necessarily claim 1)
- Use a non-PVC flexible container but not a 3–7 multilayer polyolefin co-extruded film as defined in claim 2.
- Avoid EVA as the inner-most contact layer as required in claim 11.
- Use port/closure materials not qualifying as “suitable for terminal sterilization” per the dependent claim language.
Sterilization changes that likely avoid method dependents (and may affect product state)
- Avoid heat-moist sterilization, or run autoclaving outside 110–130°C or 7–60 minutes.
- Changing sterilization chemistry or cycles could also change ester formation, which can become relevant for claim 11 performance metrics.
What patent strength looks like from the claim drafting
High specificity increases validity and infringement leverage for the patentee when the market uses the same formulation and packaging platform. The claim is not just “esmolol in non-PVC.” It is:
- narrow pH
- narrow co-solvent ranges
- terminal sterilization requirement
- container structural features
- stability/ester outcome limits
- polymer contact requirements
Litigation risk for generic/competitor entry is highest where the competitor’s product is “terminally sterilized in a non-PVC flexible container” and uses the same co-solvent system and buffer approach to maintain stability at pH 4.5–5.5.
Key Takeaways
- US 8,829,054 centers on a sterile esmolol hydrochloride premix in non-PVC flexible containers with pH 4.5–5.5, ethyl alcohol 0.1–3% w/v, and propylene glycol or glycerin 0.1–3% w/v, followed by heat-moist terminal sterilization.
- Independent claim 1 is broad enough to cover multiple buffer salts (so long as the pH window is met) but narrow enough on co-solvent presence and concentration and on container type and terminal sterilization.
- Dependent claims tighten coverage through specific container film architecture (3–7 multilayer polyolefin co-extruded films), named polymer families, buffer salts, and in claim 11 through post-autoclave stability and low related ester formation plus an EVA inner-most contact layer.
- Method claims cover preparation steps including autoclaving conditions in narrower dependents (110–130°C, 7–60 minutes).
- A use claim exists for bradycardia/hypotension control during CT diagnosis, but it is tethered to the claimed product of claim 1.
FAQs
1) What formulation elements of US 8,829,054 are easiest to alter to avoid claim 1?
Avoid at least one of: pH 4.5–5.5, ethyl alcohol 0.1–3% w/v, propylene glycol or glycerin 0.1–3% w/v, or esmolol concentration 5–40 mg/mL, or avoid heat-moist terminal sterilization in the sealed non-PVC flexible container.
2) Does using a non-PVC container automatically avoid infringement?
No. Claim 1 requires non-PVC flexible plastic plus the specific formulation ranges and terminal heat-moist sterilization.
3) How does claim 11 differ from claim 1 in practical scope?
Claim 11 adds post-autoclave performance thresholds (esmolol loss <2%, related ester <0.5%) and a specific inner-most contact polymer requirement (EVA copolymer), making it narrower but also more testable.
4) Can a competitor avoid dependent buffer claims (5–7) while still hitting claim 1?
Yes. Claim 1 only requires a buffering agent maintaining pH 4.5–5.5; claims 5–7 specify certain buffer families/salts.
5) What is the litigation significance of the method claims (13–18)?
They can reach manufacturing and sterilization steps even where final product packaging sourcing differs, especially where autoclaving conditions are within the dependents’ ranges.
References
- US Patent 8,829,054, claims 1–18 (as provided in prompt).
