Details for Patent: 7,981,938

Which drugs does patent 7,981,938 protect, and when does it expire?

Patent 7,981,938 protects COLCRYS and is included in one NDA.

Summary for Patent: 7,981,938

Title:	Colchicine compositions and methods
Abstract:	Stable ultrapure colchicine compositions comprising ultrapure colchicine and a pharmaceutically acceptable excipient are described. The compositions can be tablets. Methods for preparing such compositions and methods of use are also disclosed. Methods of treating gout flares with colchicine compositions are also disclosed.
Inventor(s):	Matthew W. Davis
Assignee:	Mutual Pharmaceutical Co Inc
Application Number:	US12/687,406
Patent Litigation and PTAB cases:	See patent lawsuits and PTAB cases for patent 7,981,938
Patent Claim Types: see list of patent claims	Use;

US Patent 7,981,938: Scope, Claim Structure, and U.S. Patent Landscape for Colchicine Dosing in Gout Flare During Prophylaxis

What does the patent claim cover in the U.S.?

US 7,981,938 claims a specific method of treating an acute gout flare using oral colchicine in a patient who is already on colchicine prophylaxis for gout flare prevention. The claim is not directed to colchicine compositions generally, nor to flare treatment in colchicine-naïve patients. It is limited to an on-prophylaxis patient and to a timed dosing regimen.

Claim 1: Method steps and dose sequence (verbatim structure, summarized)

The claim requires all of the following elements:

1. Patient condition

   • The patient has a gout flare while undergoing colchicine prophylactic treatment of gout flares.

2. Acute flare dosing (two-dose loading within about 1 hour)

   • Administer 1.2 mg oral colchicine at the onset of the acute flare.
   • Follow with 0.6 mg oral colchicine about one hour later.

3. Transition back to prophylaxis

   • After waiting 12 hours, continue prophylaxis with:
     • 0.6 mg or 1.2 mg oral colchicine daily.

Practical read of claim scope

To infringe claim 1, an accused method must:

• Use oral colchicine.
• Occur in a patient who is already receiving colchicine prophylaxis (not a one-time acute-only course).
• Match the onset dose of 1.2 mg, then 0.6 mg about 1 hour later.
• Resume prophylaxis after a 12-hour waiting period, using a daily maintenance dose of 0.6 mg or 1.2 mg.

The claim language frames a closed-loop regimen: acute flare treatment is embedded into an ongoing prophylaxis program, with explicit timing anchors (1 hour and 12 hours).

Source: US 7,981,938, claim 1 (provided claim text by user).

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How narrow or broad is the claim as written?

Key limiting features

The scope tightens around multiple fixed constraints:

• Indication context: “gout flare” treatment is required.
• Patient context: the patient must already be on “colchicine prophylactic treatment.”
• Route: “oral colchicine” only.
• Dose geometry:
  • 1.2 mg at onset (first dose)
  • 0.6 mg approximately 1 hour later (second dose)
• Timing geometry:
  • “about one hour later”
  • “after waiting 12 hrs” before resuming daily prophylaxis
• Maintenance dosing choices: daily 0.6 mg OR 1.2 mg.

What the claim does not cover (by implication of claim requirements)

Even without looking at dependent claims, the stated claim 1 does not read on:

• Patients not receiving prophylaxis at baseline.
• Alternative oral flare dosing (for example, 0.6 mg-only loading, different intervals, or a different number of loading doses).
• IV colchicine.
• Acute dosing that does not integrate with prophylaxis resumption after 12 hours.

Entry points for design-around

A manufacturer or prescriber looking to avoid claim 1 infringement would look for method variants that break one of the required constraints:

• Treat the flare in a prophylaxis-naïve patient (or document prophylaxis is not active).
• Change the flare loading schedule such that the regimen no longer matches 1.2 mg at onset and 0.6 mg about 1 hour later.
• Alter the timing so prophylaxis is not resumed “after waiting 12 hrs.”
• Use maintenance doses outside the claimed set (not 0.6 mg or 1.2 mg daily).

This is a “method of treatment in a specific dosing workflow” claim, which is typically harder to avoid in practice unless dosing is meaningfully altered.

Source: US 7,981,938, claim 1 (provided claim text by user).

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How does this claim compare to the standard colchicine framework for gout?

Claim 1 matches an escalation then prophylaxis resumption pattern

US 7,981,938 sits in the operational space where:

• An acute flare is treated with a loading approach (1.2 mg then 0.6 mg near 1 hour).
• Prophylaxis is then continued at a daily maintenance dose (0.6 mg or 1.2 mg), with a 12-hour waiting period before returning to prophylaxis dosing.

Why the “on-prophylaxis” qualifier matters

A large share of colchicine patenting and regulatory dosing content historically focuses on either:

• flare treatment in general, or
• prophylaxis for flare prevention during initiation of urate-lowering therapy.

The differentiator in claim 1 is the integration step: it defines what to do when a flare occurs while prophylaxis is ongoing. That conditional context narrows the use case to exactly those patients whose baseline regimen is colchicine prophylaxis.

Source: US 7,981,938, claim 1 (provided claim text by user).

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What is the U.S. patent landscape likely to look like around this claim?

Because only claim 1 text is provided, the landscape below focuses on claim-structure-driven positioning and where competing claims typically attach in the U.S. for colchicine and gout dosing. It also flags how the presence of an “on-prophylaxis” method claim affects freedom-to-operate (FTO) analysis in practice.

Landscape clusters that tend to surround colchicine gout dosing

1) Claims on acute flare dosing in general

These typically cover oral colchicine dosing schedules for flare treatment, often with:

• fixed loading dose(s),
• defined time intervals,
• stop rules (renal impairment, toxicity limits, etc.),
• and sometimes contraindication-specific variants.

Impact vs US 7,981,938: General flare dosing claims may not be infringed by a regimen designed for “on-prophylaxis” patients unless they also cover the prophylaxis integration steps.

2) Claims on prophylaxis dosing

These cover:

• low-dose daily colchicine regimens for flare prevention,
• dosing choices (commonly 0.6 mg once or 0.6 mg once/twice daily, depending on the claimed framework),
• special populations.

Impact vs US 7,981,938: Prophylaxis-only claims are typically easier to fall into if the daily maintenance regimen matches, but claim 1 requires the flare treatment overlay and timing integration.

3) Claims on “breakthrough” flares during ongoing prophylaxis

This is where US 7,981,938 is positioned. Competing patents in this cluster often cover:

• what to do when a flare occurs while prophylaxis is already running,
• how to adjust dosing temporarily,
• when to return to baseline maintenance.

Impact vs US 7,981,938: The presence of an “about one hour later” second dose and a “waiting 12 hrs” step before resuming daily prophylaxis makes the regimen a high-specificity target. Competing claims would be checked for:

• alternative time intervals (for example, 2 hours instead of 1),
• different onset-first dose sizes,
• different return-to-prophylaxis windows (not 12 hours),
• different daily maintenance options.

How to read claim 1 within a U.S. FTO framework

A typical FTO question is not “Is colchicine used for gout?” but “Does the accused clinician-patient workflow match every step of a claimed method?”

For US 7,981,938, the workflow match must include the prophylaxis status and dosing timepoints:

• “patient undergoing prophylactic treatment” (baseline condition)
• exact flare loading: 1.2 mg at onset, then 0.6 mg about one hour later
• prophylaxis resumption: after 12 hours, daily 0.6 mg or 1.2 mg

If any one anchor is off, claim 1 would not read under a strict literal infringement analysis.

Source: US 7,981,938, claim 1 (provided claim text by user).

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What would be “core infringement” activity for competitors?

The most direct infringement risk is clinical use cases where:

• a patient already takes colchicine daily as prophylaxis for gout flare prevention,
• a flare starts,
• the clinician advises the patient to take 1.2 mg at onset, then 0.6 mg about one hour later,
• then the patient returns to daily prophylaxis only after 12 hours, using either 0.6 mg or 1.2 mg daily.

For product developers and payers, the key is that the patent is method-based; it is triggered by dosing behavior, not by drug packaging. That makes educational materials, label language, clinical protocols, and prescribing guidelines potential downstream vectors in an enforcement scenario.

Source: US 7,981,938, claim 1 (provided claim text by user).

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How long does this claim remain relevant in the U.S.

Patent term depends on filing date, any patent term adjustments, and regulatory exclusivity effects. No filing history, grant date, or expiration data was provided in the prompt, and exact term status cannot be calculated from claim text alone.

Source: Not available from provided information (claim text only).

(Per instructions, no additional assumptions are introduced.)

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Claim construction hotspots likely used in dispute

Even without full specification text, claim 1’s phrasing points to likely construction issues:

1. “about one hour later”

   • Courts often interpret “about” with tolerance; the tolerance boundary matters for whether alternative dosing schedules match.

2. “after waiting 12 hrs”

   • The “waiting” period can be a factual issue:
     • whether it starts after the second dose,
     • whether time is measured in actual hours versus approximate,
     • whether missed doses break the timing requirement.

3. “daily” prophylactic continuation with “0.6 mg or 1.2 mg”

   • The regimen allows two maintenance dose options.
   • A variant using 0.3 mg, 0.9 mg, or a tapered schedule would fall outside the express “0.6 mg or 1.2 mg” set.

4. “patient undergoing colchicine prophylactic treatment”

   • In litigation, a key evidentiary point is the baseline prophylaxis status at flare onset (active prophylaxis in place).

Source: US 7,981,938, claim 1 (provided claim text by user).

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Key Takeaways

• US 7,981,938 claim 1 is a tightly specified oral colchicine method for treating a gout flare in a patient already on colchicine prophylaxis.
• The claimed regimen requires 1.2 mg at flare onset, followed by 0.6 mg about 1 hour later, then resuming prophylaxis after 12 hours at 0.6 mg or 1.2 mg daily.
• The claim’s strongest narrowing features are the “on-prophylaxis” patient qualifier and the timepoint integration (1 hour and 12 hours), making workflow match the infringement trigger.
• Design-around is most plausible by breaking at least one of the fixed dosing/timing anchors or by treating non-prophylaxis patients, but only a workflow-matching assessment can determine infringement risk.

Source: US 7,981,938, claim 1 (provided claim text by user).

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FAQs

1) Is the patent about colchicine in general for gout?

No. Claim 1 is a method of treating an acute gout flare using oral colchicine specifically in a patient already on colchicine prophylaxis, with a defined dosing and timing sequence.

2) Does it cover a different interval than “about one hour later”?

Claim 1 requires a second dose “about one hour later.” A substantially different interval may avoid literal reading depending on construction of “about.”

3) What doses are explicitly allowed for the flare loading and maintenance?

Flare loading: 1.2 mg at onset and 0.6 mg about 1 hour later.
Maintenance: 0.6 mg or 1.2 mg daily after a 12-hour wait.

4) Does the claim cover patients not on prophylaxis?

Not as written. The method requires a patient who is “undergoing colchicine prophylactic treatment” at flare onset.

5) Is the patent product-specific or workflow-specific?

Workflow-specific. The claim targets the treatment method defined by patient context and dosing steps, not a particular drug formulation or device.

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References

[1] US Patent 7,981,938, claim 1 (method of treating a gout flare with colchicine in a patient undergoing colchicine prophylactic treatment of gout flares).

Drugs Protected by US Patent 7,981,938

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Patented / Exclusive Use	Submissiondate
Takeda Pharms Usa	COLCRYS	colchicine	TABLET;ORAL	022352-001	Jul 29, 2009		DISCN	Yes	No						A METHOD FOR TREATMENT OF GOUT FLARES DURING PROPHYLAXIS