Details for Patent: 8,672,898

Summary for Patent: 8,672,898

Title:	Automatic injection device with reset feature
Abstract:	The present invention relates to a dose setting and expelling device comprising a drive member and a dose setting mechanism which simultaneously sets a given dose and stores the energy necessary for a subsequently driving the drive member in order to expel a dose of medicine from an injection device. According to the invention the dose setting mechanism allows adjustment in both directions, such that a given set dose can be reduced or cancelled by reversing the input motion, typically by rotating a setting member backwardly, this in contrast to the known devices which either requires an additional release mechanism or which cannot be reversed at all.
Inventor(s):	Christian Enggaard
Assignee:	Novo Nordisk AS
Application Number:	US10/970,868
Patent Litigation and PTAB cases:	See patent lawsuits and PTAB cases for patent 8,672,898
Patent Claim Types: see list of patent claims	Use; Delivery; Device;

Scope and Claims Dissection of U.S. Patent 8,672,898: Dose-Setting/Drive Mechanism for Multi-Dose Injection Devices with Rotatable Helical Scales and Energy-Storage Springs

Executive summary. U.S. Patent 8,672,898 centers on a mechanical dose-setting system for drug injection devices that (i) uses a user-rotated, axially fixed dose-setting member to store energy in an internal spring (or elastic element) and (ii) supports “down-titration” by rotating the dose-setting member in the opposite direction without expelling drug. A latch retains the set position against spring bias until the user triggers delivery, at which point the spring releases to create relative rotation between threaded drive elements and converts that rotation to distal plunger/piston motion. Claim scope is dominated by the combination of: a non-axially translating dose-setting knob/assembly; opposite-direction rotation that reduces a set dose with no expulsion; energy storage in a spring/elastic element; latch release; threaded drive engaging an axially fixed threaded component (or threaded/non-axially displaceable element) to drive an expelling member; and a helical numeric scale on an external rotatable surface visible through a housing window as the dose setting member rotates.

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What does U.S. Patent 8,672,898 claim about dose setting without drug expulsion?

Core inventive concept in the independent claim (Claim 1). The heart of the patent is a user interface and mechanical logic that separate “dose increase” from “dose decrease.” In the set/increase direction, the dose-setting member is rotated against spring bias, storing energy. In the reduction direction, the user rotates the same dose-setting member in the opposite sense to reduce the set dose without expelling drug.

Key claim elements (Claim 1) that define scope

Claim 1 is drafted as a dose setting device used “in combination with an injection device” having a fluid-filled reservoir and a drive member that expels a dose from the reservoir.

Within Claim 1, the following elements are repeatedly anchoring:

• Axially fixed dose-setting member
  Dose-setting occurs “when dose setting and adjusting … does not move axially.”

• Opposite-direction rotation behavior

  • First direction: rotation is “against the bias of the spring” and stores energy in the spring for later expelling.
  • Second opposite direction: rotating reduces the size of a set dose and “when dose size reduction is necessary, no drug is expelled.”

• Latch retaining the set position
  A “releaseable latch” retains the dose-setting member in the set position against spring bias. The latch release is what transitions the system from dose-setting logic to expulsion logic.

• Latch release causes distal driving by converting stored energy into relative rotation
  Release causes the spring to induce “relative rotational motion between the drive member and the axially fixed component having the internal thread,” driving the drive member distally to expel.

• Threaded architecture with non-locking and pitch-defined behavior (supported by dependents)
  Multiple dependent claims add “non-locking type” threads and pitch-angle functionality that yields axial movement of a drive member via axial force applied by the spring.

• Helical scale and windowed indicator on a rotatable skirt/dose-setting surface
  “Numbers are printed along a helical line … so that only a portion of the numbers pass through a window … during setting … reduction … and expulsion … when the skirt rotates.”
  This is a concrete structural/visual limitation. The claim ties the numeric scale to a helical line and to window visibility during set, reduction (without expulsion), and injection.

How Claim 1 captures the “dose-down without expulsion” design pattern

The patent claims a mechanical sequence where dose reduction is not implemented by triggering a partial expulsion cycle. Instead, reduction is performed as a rotational adjustment that changes the “set position” while the latch still retains the member and the spring energy logic is managed so that no expulsion occurs.

This claim structure is important because many competitors solve “down-titration” by allowing reverse rotation but still relying on gear backlash or partial drive engagement that can intermittently move a plunger/piston. Claim 1’s language is designed to exclude that by requiring no expulsion during opposite-direction rotation used for reduction.

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How are dependent claims 2–18 narrowing the mechanical construction and drive train?

Dependent claims add specificity around reservoir geometry, piston-drive engagement, coupling members, non-rotational sliding elements, and detailed coupling mechanics that prevent spring counter-rotation.

Fluid reservoir and piston-drive integration (Claims 2)

• Claim 2 specifies the reservoir ends: foremost end for needle coupling and rearmost end closed by a piston sliding in the reservoir.
• The “drive member” is “in the form of a piston drive member” that engages the piston to expel when spring-driven forward motion occurs.

Scope effect: This narrows the device toward a piston-in-reservoir architecture and ties the expelling member to a piston rather than alternative fluid expelling modes.

Coupling member and straining spring logic (Claims 3–8, 12–15)

• Claim 3 introduces a coupling member displaceable with dose setting assembly; spring acts on coupling member; coupling acts on dose setting member.
• Claims 4, 13: mutually cooperating surfaces provide coupling such that dose-setting rotation strains the spring as the coupling member is driven backwardly.
• Claims 5, 12: one component is rotationally mounted on the drive member; the other is in sliding non-rotational engagement.
• Claims 6, 11: threaded portion of drive member; dose-setting member rotationally mounted; that yields axial movement of dose-setting member relative to drive member (a possible alternate embodiment to Claim 1’s “does not move axially” limitation, but Claim 1 already states no axially movement during dose setting; these dependent features read as different mechanical implementations within the overall system language).
• Claims 7, 14: non-locking threaded connections allow dose-setting member rotation either direction while preventing spring counter-rotation.
• Claims 8, 15: coupling provides resistance against rotation, enough to prevent spring counter-rotation, but easily overcome by a user.

Scope effect: This cluster is about spring counter-rotation suppression during bidirectional knob rotation. It supports non-locking threads and friction/sector-tooth coupling that behaves like a controlled ratchet/resisting interface but still allows manual reverse rotation.

Sector-tooth ramp coupling mechanics (Claim 16)

• Claim 16 describes coupling parts with “sector shaped teeth” and ramp shaped edges.
• Ramp edges abut; when dose setting member is rotated either direction, teeth slide over each other with ramp shaped parts.
• The claim adds a “jump back” event when tops of teeth are reached, and the pitch chosen so jump-back occurs each time dose is increased by a given unit.

Scope effect: This adds a relatively specific mechanical implementation. Competitors using different coupling geometries or pure friction couplings may avoid this dependent claim, though Claim 1 and broader dependents may still read.

Frictional coupling (Claim 17)

• Claim 17 provides an alternate: coupling is frictional between cooperating surfaces, compression force provided by the spring acting on coupling member.

Scope effect: Covers friction-based coupling architectures.

Latch acts on the drive member (Claim 18)

• Claim 18 specifies latch acts on the drive member (vs latch acting directly on the dose-setting member or other component).

Scope effect: Narrows to latch-contact location.

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What additional scope do claims 19–26 add across syringe and pen embodiments?

Claims 19–26 expand the invention into a broader set of “dose setting and drive mechanism” and specifically recite injection syringe and injection pen configurations, plus details of dose indicator rotation.

Mechanism claim variant (Claim 19)

Claim 19 is structurally similar to Claim 1 but written at a higher system level:

• threaded drive member expelling dose by relative rotational motion with a “non-axially displaceable element”
• elastic element stores energy
• dose setting element rotates in first direction to store energy against elastic bias
• second opposite rotation reduces set dose without expelling
• dose setting element does not move axially with respect to the housing
• latch retains set position against elastic bias
• release causes relative rotational motion between drive member and non-axially displaceable element and expels
• helical numbers printed on external surface of dose setting member visible through window during setting, reduction, and expulsion

Scope effect: Claim 19 reads as a generalized mechanism claim that can target various needle-based injectors so long as the dose-down logic, latch release, and helical-window indicator logic are present.

Injection syringe embodiment (Claim 20)

Claim 20 recites:

• “dose setting knob” rotatable but not axially displaceable
• helically arranged scale of numbers and window displaying one number
• latch and elastic energy storing member
• user rotates knob to set dose, storing energy
• knob freely rotatable in opposite direction to reduce set dose without expelling
• latch actuation releases energy to expel to reservoir containing medication
• during expulsion, dose indicator rotates toward “zero position” (initial scale position prior to setting), and rotation visible in window
• only a portion of numbers visible at any time

Scope effect: Adds syringe-specific mechanics and an explicit “zero return” narrative aligned with the indicator logic.

Injection pen embodiment (Claims 21–26)

Claim 21 recites:

• housing with distal end for injection needle attachment
• rotatable dose setting element with respect to housing but axially fixed
• dose indicator assembly with scale of numbers and window
• threaded plunger rod drives distally to expel
• threaded element axially fixed relative to housing engages plunger rod; relative rotation moves plunger rod distally
• spring stores energy via rotation of dose setting element; torsional force applied to one or both threaded elements
• latch: first position energy stored, second position energy released
• during setting: dose setting element rotates against spring bias storing energy
• during injection: latch actuated; relative rotational motion occurs; plunger rod advances axially
• during setting: dose indicator rotates with dose setting element away from initial position
• during dose ejection: dose indicator automatically rotates toward initial position while dose expelled so indicator returns to zero when expulsion completes
• distal and proximal ends do not move axially relative to housing

Dependents:

• Claim 22: threaded element rotatable with respect to housing; plunger rod does not rotate during ejection
• Claim 23: threaded element axially fixed; plunger rod rotates during ejection
• Claim 24: setting/adjust uses first direction set, second opposite direction reduce; helically arranged scale
• Claim 25: setting/adjust uses first direction set, second opposite reduce; scale not explicitly limited to helical (but claim 24 is where helical is explicit)
• Claim 26: dose indicator rotates less than one full revolution

Scope effect: The pen claims lock in axially fixed dose setting element, threaded plunger rod/axially fixed threaded element interaction, spring/torsion energy transfer, and return-to-zero indicator behavior. Claim 26 adds a quantitative-ish indicator rotation limitation (<360 degrees).

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What is the claim scope boundary created by the helical numeric scale and window?

The helical scale appears in Claim 1 and Claim 19 and is reiterated in syringe/pen claims. It is not merely “a dose indicator.” It requires:

• numbers printed along a helical line on an external surface of a rotatable skirt/dose-setting element
• a window in the housing
• only a portion of the numbers pass through/visible through the window during:
  • dose setting
  • dose size reduction without expulsion
  • dose expulsion

Practical implication: A competitor can avoid this literal limitation by using a different indicator geometry (e.g., linear scale, radial markings on a non-helical surface, digital display, or a helical scale that does not present “only a portion of the numbers” through a housing window during reduction and expulsion). If the competitor’s indicator is non-helical, the helical-window limitation becomes a strong non-infringing path.

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How might competitors design around the latch and opposite-direction no-expulsion requirement?

Claim 1’s “no drug is expelled” during second-direction rotation is a functional limitation tied to the mechanical system response during reduction.

A design-around approach that is consistent with the claim boundary would be to ensure that reversing the dose knob changes a different state such that any plunger movement is decoupled from dose reduction mode. However, from an infringement perspective, the claim’s wording creates an enforcement hook: if any expulsion occurs during reduction rotation, literal “no drug is expelled” becomes harder to meet. If no expulsion occurs, but the mechanism still does some partial energy release or advances a fluid path, courts typically analyze how “expelled” is interpreted and whether measurable fluid movement counts.

A more straightforward boundary is the latch function: energy storage and release are triggered by latch release. If a competitor uses a different trigger (e.g., purely continuous drive without a releaseable latch that retains set position), they may fall outside latch-based claim language.

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Patent landscape for US 8,672,898: what to map for freedom-to-operate and enforcement

Given only the claim text provided, the patent landscape analysis can be limited to what the claims themselves indicate for likely claim clusters and litigation-risk themes. The landscape sections below outline what matters for enforcement, licensing, and generic risk in the mechanical dose-setting domain.

Landscape map by technical axis

1. Dose reduction without expulsion
   • Central to Claim 1 and Claim 19; appears again in syringe and pen claims.
2. Energy storage spring and latch-release architecture
   • Central to Claim 1 and Claim 19; expanded in syringe/pen claims.
3. Threaded drive conversion from rotation to axial expulsion
   • Threaded drive member engages an axially fixed threaded/internal-thread element or non-axially displaceable element; relative rotation produces distal motion.
4. Non-axially translating dose-setting knob
   • Explicit in Claim 20 and in pen claims; supported in mechanism claim language.
5. Helical helical-scale indicator with windowed partial visibility
   • Concrete structural limitation repeated across the independent mechanism claim and syringe/pen.

Likely “most asserted” claim targets (based on enforceability and specificity)

• Independent Claims 1 and 19: broadest mechanical logic covering the core dose-setting behavior plus helical-window indicator.
• Claim 20 (syringe) and Claim 21 (pen): strong device-format alignment with common commercial injector platforms.
• Claim 16: more specific coupling geometry; used as a fallback position in prosecution or enforcement.
• Claim 26: numeric constraint for indicator rotation magnitude; only relevant if the competitor’s indicator rotates less than one full revolution.

Jurisdictions likely implicated

The patent is a US patent, so enforcement will be US-focused. The mechanical nature means counterpart patents commonly appear in:

• PCT national phase filings in major medical device markets
• EP and CN equivalents for injector form factors But those require external bibliographic/portfolio data to document, which is not present in the provided input.

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Key Takeaways

• U.S. Patent 8,672,898 protects a specific injector dose-setting logic: bidirectional rotation with a latch, where the opposite direction reduces dose size without expelling drug.
• The claims combine functional dose-reduction behavior with concrete mechanical/indicator structure: threaded drive conversion, an energy-storing spring/elastic element, and a helical numeric scale visible through a housing window as the dose member rotates.
• The strongest infringement hooks are Claims 1/19 for the core mechanism and the repeated helical-window indicator limitation; Claims 20/21 add format-specific reinforcement for syringe and pen.
• Design-around leverage is most plausible through changing indicator structure (non-helical or non-windowed partial visibility logic), altering the latch/energy release trigger, or preventing the exact mechanical sequence where reduction rotation occurs without expulsion under the claimed architecture.

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FAQs

1. Do the claims require a helical scale on a rotatable skirt, or can a different dose indicator satisfy?
2. Is the “no drug is expelled” limitation likely interpreted strictly as zero fluid movement, or does any measurable displacement count?
3. What claim elements matter most if an injector uses a digital display instead of a windowed helical scale?
4. How do the non-locking threaded relationships and spring counter-rotation prevention features affect infringement analysis?
5. If a pen’s dose indicator returns to zero, does that increase risk under the syringe/pen dependent claims?

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References

1. U.S. Patent 8,672,898.

Drugs Protected by US Patent 8,672,898

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

Foreign Priority and PCT Information for Patent: 8,672,898

Foriegn Application Priority Data
Foreign Country	Foreign Patent Number	Foreign Patent Date
Denmark	2001 00018	Jan 5, 2001

International Family Members for US Patent 8,672,898

Country	Patent Number	Estimated Expiration	Supplementary Protection Certificate	SPC Country	SPC Expiration
Austria	296650
China	1313168
China	1509193
Germany	60204422