Details for Patent: 8,097,653

Summary for Patent: 8,097,653

Title:	Dosage unit comprising a prostaglandin analog for treating constipation
Abstract:	A dosage unit for treating constipation in a human patient is described. The dosage unit of the invention comprises a halogenated prostaglandin analog and a pharmaceutically suitable excipient. The dosage unit relieves constipation without substantial side effects.
Inventor(s):	Ryuji Ueno, Myra L. Patchen
Assignee:	Sucampo GmbH
Application Number:	US10/293,516
Patent Litigation and PTAB cases:	See patent lawsuits and PTAB cases for patent 8,097,653
Patent Claim Types: see list of patent claims	Use; Composition;

US Patent 8,097,653 Scope, Claim Construction, and US Patent Landscape for PG Analog Constipation Therapy (48–72 μg/day)

US Patent 8,097,653 is a US method-of-treatment patent with narrow dosing and chemical-structure guardrails. The enforceable claim scope is primarily constrained to: (i) administering a specific prostaglandin (PG) analog within a tight per-dose amount (24 μg ±10%), (ii) achieving a specific total daily dose window (about 48–72 μg/day), and (iii) using a pharmaceutically suitable excipient (with dependent claims narrowing to oral excipients and a medium chain fatty acid). As a practical matter, designing around the patent is most feasible by changing the daily dose outside the claimed range, altering the PG analog structure so it no longer falls within the Formula (I) definition (including the A1/A2 fluorine requirement and B definition), or avoiding the claimed dosage-unit formulation/excipient parameters.

Quick claim-scope readout

• Independent claim coverage (Claim 1): constipation relief in humans via repeated dosing of a dosage unit containing 24 μg ±10% of a PG analog of Formula (I) with A1 and A2 = fluorines and B = —COOH (or its acceptable derivatives), plus a pharmaceutically suitable excipient, achieving 48–72 μg/day total PG analog dose.
• Dependent claim narrowing:
  • Claim 2: PG analog is a monocyclic tautomer of Formula (I).
  • Claim 3: excipient is orally acceptable.
  • Claim 4: excipient is medium chain fatty acid.
  • Claims 5–7: locks total daily dose and B identity further (48 μg/day; 24 μg per unit; B is exactly —COOH).

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What does US Patent 8,097,653 claim cover for constipation treatment dosing and PG analog structure?

Core answer: The patent claims a method for relieving constipation by administering a dosage unit containing a tightly defined amount of a fluorinated PG analog (Formula (I)) plus an excipient, with the dosing schedule controlled so that total daily dose is about 48–72 μg/day.

Independent claim 1: claim-map essentials

Claim 1 elements (from the provided claim text):

1. Indication: human patient in need of relief of constipation.
2. Administration form: each dosage unit contains:
   • (i) 24 μg ±10% of a PG analog represented by Formula (I) and/or its tautomer, and
   • (ii) a pharmaceutically suitable excipient.
3. Structure constraints on Formula (I):
   • A1 and A2 are fluorine atoms
   • B is —COOH, including pharmaceutically acceptable salts, esters, or amides of that acidic function.
4. Dose schedule constraint: administer the dosage unit enough times per day such that:
   • total daily dose of the PG analog is about 48–72 μg.
5. Result: “to thereby relieve constipation in the patient.”

Enforcement posture implied by this structure:

• The claim is not a broad “use PG analog X for constipation.” It is a dose-and-structure-limited use. A party arguing invalidity or noninfringement would focus on:
  • whether the administered molecule is within the Formula (I) definition (A1/A2 fluorines; B identity/derivatives),
  • whether the per-dose amount is within 24 μg ±10%,
  • and whether the administered regimen yields total daily PG analog dose about 48–72 μg/day.

What “about” does in claim 1 (practical litigation value)

The patent uses two “about” terms:

• per dosage unit amount: 24 μg ±10%
• total daily dose: “about 48–72 μg”

In US litigation, “±10%” is a tighter numeric boundary than “about.” “About 48–72” can still leave room for argument, but it is tethered to a defined numeric range. Design-around arguments typically target the outside of the range (for the daily total) and the outside of the ±10% band (per unit).

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How are dependent claims 2–7 narrowing the PG analog and excipient scope?

Featured snippet answer: Dependent claims narrow to (i) a monocyclic tautomer form, (ii) oral excipients, (iii) medium chain fatty acid excipients, and (iv) locked numeric dosing and B identity.

Dependent claim 2: monocyclic tautomer

• Claim 2: the PG analog is a monocyclic tautomer of Formula (I).
• Scope implication: If a competitor uses a different tautomer form, they may reduce literal infringement risk for Claim 2 while still potentially falling under Claim 1 if Claim 1 covers “and/or its tautomer.” Claim 1 already includes tautomer coverage, so Claim 2 is mostly additive narrowing rather than excluding tautomer types covered by Claim 1.

Dependent claim 3: orally acceptable excipient

• Claim 3: excipient is orally acceptable.
• Scope implication: If the formulation is not oral (example: subcutaneous or rectal route) but still administers the defined dosage unit orally? The claim requires “administering” to a human; the excipient limitation in Claim 3 may not matter for a non-oral formulation unless Claim 1 is interpreted to implicitly require an oral excipient. Claim 1 does not say oral, so Claim 3 is a supplemental narrowing.

Dependent claim 4: excipient is medium chain fatty acid

• Claim 4: excipient is a medium chain fatty acid.
• Scope implication: This is a clear formulation limitation. If a competitor uses another excipient class (e.g., different lipid, surfactant system, polymer matrix), they may avoid dependent claim coverage. Claim 1 still only requires a “pharmaceutically suitable excipient,” so infringement analysis will still anchor on Claim 1 even if Claim 4 is avoided.

Claims 5–7: numeric and identity tightening

• Claim 5: total daily PG analog dose is about 48 μg.
• Claim 6: per dosage unit PG analog amount is 24 μg.
• Claim 7: B is —COOH (not merely salts/esters/amides).

Scope implication:

• These are narrower than Claim 1. In product terms, Claim 5 and Claim 6 represent dosing regimens at the lower end of the daily range or at the precise per-unit amount, respectively. Claim 7 limits the chemical definition if a competitor uses a derivative where B is not present as —COOH but instead exists as a salt/ester/amide form during administration.

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Where does the patent’s chemical definition likely sit relative to known PG analogs for constipation?

Featured snippet answer: The claimed PG analog is a fluorinated prostaglandin analog with carboxylic acid (B = —COOH) and dosing at 48–72 μg/day, which matches the general dosing pattern used by certain PG-based constipation therapies (microgram-level, divided doses). The key legal boundary is the Formula (I) definition, not the pharmacology class.

How to think about Formula (I) in infringement terms

Even with only the textual fragments, the claim defines at least:

• Two fluorine substituents at positions corresponding to A1 and A2
• Carboxylic acid functionality as B = —COOH or acceptable derivatives

In infringement disputes, the central issues usually become:

1. Structural equivalence to Formula (I): Does the accused API match the fluorination pattern and B group definition?
2. Tautomer consideration: Claim 1 covers the tautomer(s) included by the claim (“and/or its tautomer”), complicating arguments that a different tautomer form avoids infringement.
3. Derivative handling (salts/esters/amides): Claim 1 includes acceptable salts/esters/amides, expanding coverage beyond the neutral acid form.

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When does US Patent 8,097,653 lose exclusivity, and what does term mean for generic entry risk?

This answer requires the patent’s filing date (and whether any priority supports earlier dates), which is not provided in the prompt. Without the filing date and full bibliographic data, term and expiration calculations cannot be produced accurately.

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What do Paragraph IV challenges and ANDA/Biologics pathways look like for a method-of-use PG analog constipation patent?

Direct answer: For an ANDA pathway, the infringement hook for this patent is typically the method claim requiring administration of the specified formulation/dose regimen to relieve constipation. For Paragraph IV, the typical risk is that an ANDA AND/OR label with the method of use and dosing regimen can be argued to directly infringe or induce infringement if the ANDA’s proposed labeling and instructions would administer within the claimed ranges.

This analysis is dependent on:

• whether the patent is listed in the FDA Orange Book for an approved drug product with corresponding API and dosage form,
• what exact dosing instructions appear in the ANDA labeling,
• and whether the ANDA uses a dosage unit with the same microgram content and achieves the same daily total.

Those dataset facts are not present in the prompt.

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How strong is the patent estate for this dosing and PG-analog claim strategy?

Featured snippet answer: The strength is concentrated in narrow quantitative dose constraints and tight chemical definition. That makes the patent potent against close formulation copies using the same PG analog identity and regimen, but less effective against products that shift dosing outside the 48–72 μg/day range, alter per-unit microgram content, or substitute formulations/excipients outside the dependent claim parameters.

Strength drivers

• Numeric constraints: 24 μg ±10% per dosage unit and 48–72 μg/day are litigation-friendly boundaries.
• Structural constraints: A1/A2 fluorines and B = —COOH (plus acceptable derivatives) narrow the API set.
• Method-of-use structure: claim reads on clinical use and labeling-driven administration practice.

Vulnerability drivers

• Limited claim breadth: the claim is not a wide “PG analog for constipation” claim.
• Dependents add excipient specificity: Claim 4 is narrower; Claim 3 is narrower. Avoiding those excipient choices can reduce dependent claim exposure.
• “About” language: numeric interpretation can still create margin argument, but daily total range is bounded.

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What formulation patents or method patents typically co-exist around this kind of dosing microgram regimen?

Direct answer: In PG analog constipation portfolios, companies often build estates that separately cover:

• API structure and salts/tautomers,
• formulation composition (lipid or medium-chain fatty acid systems),
• dosage unit and dosing regimen (microgram-per-unit, daily total),
• and specific therapeutic indications.

For this particular patent, the excipient constraints in Claims 3 and 4 imply that the patent family or adjacent patents likely include formulation-specific claims tied to medium-chain fatty acid vehicles and oral administration.

This section cannot list specific co-pending or cited US patents without bibliographic and patent family data.

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What generic entry risks exist if an ANDA uses a different dose or excipient for a similar PG analog?

Risk frame based on claim language:

• If total daily PG analog dose is outside ~48–72 μg/day: likely reduces literal infringement of Claim 1.
• If per-unit PG analog amount is outside 24 μg ±10%: likely reduces Claim 1 coverage.
• If API fails Formula (I) definition: reduces infringement across all claims unless equivalents are pursued.
• If excipient differs from “medium chain fatty acid” or is not orally acceptable: primarily affects dependent claims 3 and 4; Claim 1 may still be infringed if the excipient is still “pharmaceutically suitable.”

The actual generic risk in the market depends on the competitor’s chosen dose, API chemistry, and formulation platform.

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How does US Patent 8,097,653 compare with other PG analog constipation patents in scope and design-around latitude?

Comparison logic (claim-structure based):

• Compared with broad PG analog method claims (no specific microgram regimen), US 8,097,653 is narrower because it hard-codes dose-per-unit and daily totals.
• Compared with broad formulation patents (vehicle-only, no dose window), it is narrower because it requires matching both the PG analog identity and the achieved daily dosing.
• Compared with process/manufacturing patents, this is narrower on chemistry synthesis but broader in enforceability against labeling-driven administration.

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Key Takeaways

• US Patent 8,097,653 is a method-of-treatment patent for constipation that is constrained to administering a fluorinated PG analog defined by Formula (I) with A1/A2 fluorines and B = —COOH (or acceptable derivatives).
• The enforceable claim scope hinges on two numeric boundaries: 24 μg ±10% per dosage unit and about 48–72 μg/day total daily dose.
• Dependent claims narrow further to monocyclic tautomer (Claim 2), oral excipient (Claim 3), and medium chain fatty acid excipient (Claim 4), plus a locked about 48 μg/day (Claim 5), 24 μg per unit (Claim 6), and B = —COOH (Claim 7).
• Design-around is most viable by shifting dosing outside the claimed numeric windows, altering API structure so it no longer meets Formula (I), or changing formulation/excipient class to avoid dependent claim territory.

FAQs

1. How do microgram-per-dose and total daily dose ranges affect infringement risk for method-of-use PG analog patents?
2. Does a tautomer difference avoid infringement when the claim covers “and/or its tautomer”?
3. Can using a different excipient avoid dependent claims limited to medium chain fatty acids while still infringing Claim 1?
4. How do labeling instructions and dosing regimens drive method-of-use infringement exposure in ANDA Paragraph IV cases?
5. If a competitor administers a PG analog as a salt/ester/amide, how does “B = —COOH including salts/esters/amides” change chemical design-around strategy?

References

1. Provided claim text for US Patent 8,097,653 (claims 1–7).

Drugs Protected by US Patent 8,097,653

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 8,097,653

Country	Patent Number	Estimated Expiration	Supplementary Protection Certificate	SPC Country	SPC Expiration
European Patent Office	2298314		92826	Luxembourg
Argentina	037524
Argentina	098997
Austria	522218
Brazil	0214075
Canada	2464420