Critical Patent Landscape Analysis for US Patent 5,454,786 (Lyophilized Reconstitution With Angled Syringe Injection to Prevent Foaming)
US 5,454,786 is directed to systems for reconstituting lyophilized drugs inside cartridges by injecting diluent through a connector that positions a syringe at an oblique angle. The core claim logic is mechanical (cartridge + connector geometry + syringe orientation + inlet/plunger structure) coupled to a functional outcome: diluent impinges on and runs down an inner wall before contacting the lyophilized compound, preventing foaming.
What does US 5,454,786 claim cover and what does it require to infringe?
Short answer: The independent claim 1 requires (i) a lyophilized drug in a cartridge with inlet and plunger, (ii) a connector with a neck coaxial to the cartridge axis and a tubular portion whose axis is at an oblique angle to the cartridge axis, (iii) a syringe inserted into the connector portion so the needle points toward the inner cartridge wall, and (iv) injection such that diluent impinges on and runs down the cartridge inner wall before contacting the lyophilized compound to prevent foaming.
Claim 1 (method) elements that are likely infringement pinch-points
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Cartridge geometry and contents
- Lyophilized compound is in an interior space defined by an inner wall.
- Cartridge has an inlet at one end and a plunger at the opposite end.
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Connector geometry
- Connector attaches to the inlet end.
- Connector has:
- neck portion coaxial with the cartridge longitudinal axis
- tubular first portion connected to the neck portion
- tubular first portion has an interior space defining an axis along its longitudinal length
- this axis is at an oblique angle relative to the cartridge axis
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Needle orientation relative to inner wall
- A syringe with needle and diluent is placed into the interior space of the oblique angled portion.
- Needle is oriented toward the inner wall of the cartridge.
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Injection flow path and sequencing to avoid foaming
- Diluent is injected via the inlet.
- Diluent must impinge on and run down the inner wall before contacting the lyophilized compound.
- The claim recites prevention of foaming as a stated purpose/functional result.
Claim 2 (method) elements that narrow the “connector” mechanism
Claim 2 is similar in concept but uses different connector framing:
- Cartridge includes an essentially annular inner wall and inlet/plunger architecture.
- Removably attaching a connector on the inlet end defines:
- an open-ended cavity for receipt of a syringe
- a tubular angled portion receiving and angularly positioning the diluent syringe
- angled portion axis at oblique angle relative to cartridge axis
- Syringe is positioned so needle extends through inlet at oblique angle.
- Injection through needle causes diluent to impinge on inner wall and run down before contacting the lyophilized compound.
In practice, claim 2 pushes toward a connector with a cavity + angled tube that supports needle placement at a selected angle.
Claim 3 (apparatus) shifts the infringement focus to hardware
Claim 3 defines an apparatus that can be easier to map to accused devices because it removes “injecting” as a requirement and replaces it with structural elements:
- Cartridge with inlet, plunger, lyophilized drug, longitudinal axis through inlet.
- Connector releasably secured to inlet end, adapted to receive and hold a syringe:
- neck portion coaxial with cartridge axis
- tubular first portion with axis forming oblique angle with cartridge axis
- syringe supported by connector at oblique angle so diluent is injected via inlet at oblique angle.
Claims 4 and 5 (apparatus dependent) add construction details
- Claim 4: neck portion received on inlet end; connector further includes tubular second portion eccentric with first portion; second portion has larger diameter and supports the syringe; this implies an eccentric geometry for balancing syringe mass or sealing.
- Claim 5: lid on tubular second portion to seal connector interior.
How do the claim terms map to “obvious design-arounds” and “hard design constraints”?
Short answer: The claims hinge on angled syringe injection relative to cartridge axis and on forcing the diluent to hit and flow down the cartridge inner wall prior to reaching the lyophilized cake. That combination is a design constraint, not just a preferred orientation.
Likely design-around strategies that are explicitly constrained
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Changing injection target geometry
- If diluent is injected so it does not impinge on the inner wall (for example, direct jet toward centerline or mixing region), it weakens the “impinge and run down” requirement under claims 1/2.
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Eliminating oblique-angle needle orientation
- If syringe/needle is maintained coaxial with the cartridge axis (or uses a different pathway that still causes wall wetting but without oblique-angle geometry), claims 1/2/3 are at risk depending on claim construction.
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Separating “connector” from “syringe positioning”
- Claims 1/2/3 use a connector that positions the syringe at an oblique angle. A design that uses a separate fixture or molded syringe geometry without the claimed connector relationship may avoid structural match, but only if the “connector” limitation is truly not met.
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Different prevention mechanism
- The claims recite foaming prevention as an outcome. If the accused device achieves the functional result without the claimed impingement-and-wall-wetting sequence, the method claims may be harder to prove, but literal infringement could still occur if the steps inherently produce the claimed sequence.
What patents protect angled cartridge reconstitution to prevent foaming?
Short answer: US 5,454,786 is part of a specific cluster: lyophilized drug reconstitution cartridges using angled injection/flow control to manage wetting and foaming, often implemented as a vialless or cartridge-based drug delivery system.
How to think about the surrounding patent estate (typical claim families)
Because you provided only the claim text (and not the full bibliographic record or family members), the landscape can only be analyzed at the claim-logic level: the most relevant competitors generally fall into these buckets:
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Connector and angle-positioning systems
- Patents focusing on mechanical connectors, angled nozzles, and syringe supports for non-coaxial injection into drug cartridges/vials.
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Cartridge inlet/plunger architectures
- Patents focusing on drug storage formats, inlet ports, and plunger-driven delivery/reconstitution architectures.
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Foaming reduction via wetting control
- Patents focusing on controlling how diluent contacts the lyophilized mass: pre-wetting, directed flow, reduced turbulence, or anti-foaming excipients and process parameters.
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Method-of-reconstitution process steps
- Patents that claim sequence: orientation, injection timing, and stepwise dilution for consistent reconstitution.
Critical observation for freedom-to-operate (FTO)
US 5,454,786’s novelty likely lies in combining:
- a cartridge concept with inlet/plunger
- a connector that forces oblique-angle needle placement
- a hydrodynamic requirement that diluent impinges on and runs down the wall before contacting the lyophilized compound
That combination is narrow compared with generic lyophilized reconstitution patents that focus only on general reconstitution steps or general anti-foaming additives.
When does exclusivity end for US 5,454,786, and what does that mean for generic or biosimilar entry?
Short answer: Patent term depends on filing date and any adjustments; without the patent’s priority/filing data, an expiration date cannot be calculated from the claim text alone.
What can be said from the claim type
- US utility patents covering device and method claims expire on the applicable statutory term from filing (plus any adjustments).
- For generic entry, the core risk is whether an ANDA applicant uses a reconstitution device/process that practices the claimed steps or uses the claimed apparatus geometry.
Practical consequence:
- If the patent is still in force in the relevant jurisdiction, entry using a substantially similar angled connector + cartridge inlet injection to wet the inner wall can trigger infringement risk regardless of the API’s separate patent status.
What Orange Book status should be expected for this patent?
Short answer: US 5,454,786 is not a formulation-specific “Orange Book drug product” patent by nature based on the claim text; it is directed to reconstitution methods/apparatus. Orange Book listings typically cover active ingredient, formulation, and method-of-use patents for approved drug products. Whether US 5,454,786 appears in Orange Book depends on assignment to an NDA/BLA product and listing decisions. That can’t be determined from claim text.
Which companies are likely practicing or challenging angled cartridge reconstitution claims?
Short answer: Without identifying the specific drug product tied to US 5,454,786, it is not possible to map assignees, NDA holders, or litigants credibly.
How strong are the claims of US 5,454,786 (novelty, claim breadth, and litigation posture)?
Short answer: The independent claims are moderately tight because they combine specific geometry (oblique connector axis relative to cartridge axis) with a specific functional wetting flow path (impinge then run down before contact). That can narrow claim scope and raise infringement proof demands, but it can also strengthen validity against prior art that focuses only on general reconstitution.
Strength drivers
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Structural limitations in apparatus claim 3
- Oblique axis relationship between connector tubular portion and cartridge axis.
- Releasably secured connector that holds syringe at oblique angle.
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Functional hydrodynamics in method claims 1 and 2
- The diluent must impinge on and run down the inner wall before contacting the lyophilized compound.
- Many prior art reconstitution systems can wet a vial or reconstitute generally, but fewer enforce a specific wall-running flow regime.
Weakness drivers
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Functional outcome language could be contested
- “whereby foaming … is prevented” may be treated as a result dependent on compound properties and injection conditions.
- If prior art inherently prevents foaming under normal operation, validity may be attacked.
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Claim interpretation risk around “oblique angle”
- Oblique includes a broad range between perpendicular and parallel; a defendant may argue their device uses near-coaxial orientation that still contacts wall but not at a claimed “oblique” angle depending on claim construction.
What is the comparison with other lyophilized reconstitution patent types?
Short answer: Compared with “shake/mix” reconstitution patents or general dual-compartment delivery systems, US 5,454,786 is more device-geometry specific. Compared with purely anti-foaming formulation patents, it is more process-mechanical.
Common adjacent claim approaches and how they differ
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Coaxial needle injection into a vial
- Often does not require an oblique-angle connector tube.
- May still wet the cake but not via the claimed impinge-and-run-down mechanism if jet is directed differently.
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Direct flow from diluent container through a fixed nozzle
- May avoid syringe-in-connector architecture.
- If no syringe is positioned at an oblique angle by a connector with the claimed axes relationship, claim 1/2/3 may not be met.
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Anti-foaming excipients in the lyophilized product
- Avoids method/apparatus limitations.
- Would reduce foaming without needing wall-running injection.
What are the key infringement scenarios for device makers and reconstitution kit vendors?
Short answer: Infringement risk is highest when a kit uses a cartridge with inlet/plunger plus an angled syringe connector that directs a needle at an oblique angle to force wall impingement and wall-running flow.
Scenario A: accused reconstitution kit includes the same connector geometry
- Connector neck coaxial to cartridge axis
- tubular portion at oblique angle
- syringe supported at that angle
- needle injects via inlet to impinge on inner wall and run down
This aligns closely with claims 1 and 3 and most likely triggers apparatus and method infringement.
Scenario B: different connector but same functional hydrodynamics
- If a device uses a different mechanical structure (e.g., a molded angled needle hub) that still achieves wall impingement and wall-running flow, infringement depends on whether the claim limitations are met literally or under doctrine of equivalents.
- Claim 3’s structural “connector releasably secured… adapted to receive and hold a syringe” and its oblique-angle geometry are central.
Scenario C: alternative cartridge geometry (non-annular inner wall)
- Claim 2 explicitly mentions an essentially annular inner wall.
- If a device uses a different inner wall geometry, claim 2 may be avoidable while claims 1 and 3 still remain plausible.
What manufacturing and IP barriers does the claim set imply?
Short answer: The barriers are primarily assembly and kit design, not chemical manufacturing.
- Connector must provide reliable sealing and stable syringe support at an oblique angle.
- Injection must occur through the cartridge inlet so the diluent impinges on and runs down the inner wall before contacting the lyophilized compound.
- Optional features in dependent claims (eccentric tubular second portion, lid sealing) imply additional kit sealing steps and geometric packaging constraints.
Key Takeaways
- US 5,454,786 is focused on angled syringe injection into a cartridge to force diluent to impinge on and run down the inner wall before contacting lyophilized drug, reducing foaming.
- Independent claim coverage is anchored on the oblique-axis connector geometry and the cartridge inlet/plunger format, with apparatus claim 3 providing strong structural hooks.
- The main design-arounds are eliminating oblique-angle needle placement as defined by the connector geometry and/or changing injection so diluent does not impinge and run down the inner wall prior to contacting the lyophilized material.
- Expiration, Orange Book listing, and litigation/assignee mapping cannot be concluded from the claim text alone.
FAQs
What is the main inventive concept in US 5,454,786?
The key concept is using a connector that positions a syringe at an oblique angle so diluent injected through a cartridge inlet impinges on the cartridge inner wall and runs down before contacting the lyophilized drug, preventing foaming.
Does US 5,454,786 protect the cartridge itself or only the reconstitution method?
It protects both: a method (claims 1 and 2) and an apparatus (claim 3) that defines cartridge + releasable connector geometry supporting an angled syringe.
Can a coaxial syringe injection avoid infringement?
Potentially. If the device does not position the syringe needle at the claimed oblique angle relative to the cartridge axis through the claimed connector architecture, it may avoid literal infringement.
Do dependent claims 4 and 5 materially narrow the apparatus coverage?
Yes. Claims 4 and 5 add an eccentric second tubular portion larger in diameter with a sealing lid, which can narrow coverage to kits using that specific connector construction.
What prior art risks exist for the claims’ “foaming prevention” functional language?
Any prior art showing that wall impingement/wetting and reduced turbulence inherently prevent foaming, or using similar angled injection mechanics, can be leveraged to challenge validity or narrow the functional impact of the “whereby foaming is prevented” limitation.
References
- United States Patent 5,454,786. (Claims provided in prompt).
