US Patent 8,309,126 Scope and Claim-Landscape Analysis: Dispersible Tablet Composition for “Compound I” and Pulmonary Arterial Hypertension Methods

US 8,309,126 is a US composition-and-method family built around a dispersible/direct-compression tablet for a defined “Compound I” (including pharmaceutically acceptable salts/solvates and a monohydrate embodiment). The claims are structurally broad at the “dispersible tablet” level, but they also include quantitated excipient ranges and operational constraints (water disintegration time). The method claim ties administration of the dispersible tablet suspension to treatment of pulmonary arterial hypertension (PAH).

Below is a claim-scope map and a practical US patent landscape view focusing on design-around risks, likely claim interpretation pressure points, and how this patent sits relative to common dispersible-tablet and solid-form IP patterns used by generic and reformulation challengers.

What does US 8,309,126 claim, and how broadly does it cover dispersible tablets?

Executive claim map (what is protected)

US 8,309,126 claims two core categories:

Dispersible tablet composition with:
- Active ingredient defined as “Compound I” of a formula (plus salts/solvates; plus a monohydrate variant).
- Any pharmaceutically acceptable excipients, with dependent claim sets specifying typical excipient classes (fillers, lubricants, disintegrants, glidants, acidifying, flavoring, sweetening).
- Quantitative excipient ranges (claim 5).
- Manufacturing method (direct compression, claims 7 and 9).
- Performance: complete disintegration in water at 15–22°C within ≤5 minutes (claim 11).
Method of treatment:
- Disperse the tablet in aqueous media to form a suspension, then administer for PAH (claim 8).

Independent claim strategy: claim 1 anchors broad composition coverage

Claim 1 is a functional composition claim:

“A dispersible tablet composition comprising … an active ingredient consisting of Compound I… and pharmaceutically acceptable excipients.”

Key scope drivers:

“Dispersible tablet” is the main structural limitation.
“Active ingredient consisting of Compound I” narrows the active to only Compound I (but still captures salts/solvates).
“Pharmaceutically acceptable excipients” is open-ended, which broadens coverage for any formulation that meets the dispersibility/tablet performance concept, unless limited by dependent claims.

Dependent claims narrow into excipient class coverage and quantitative ranges

The dependent claims create a hierarchy:

Claim 2: at least one filler + at least one lubricant.
Claim 3: further includes at least one disintegrant.
Claim 4: may include acidifying and/or flavoring and/or sweetening agents.
Claim 5: the most specific formulation capture, with multiple numeric bands for key excipient classes:
- Fillers: 40–85% w/w
- Disintegrants: 0.5–20% w/w
- Glidants: 0.1–5% w/w
- Acidifying agents: 0.5–13% w/w
- Flavoring agents: 1–15% w/w
- Sweetening agents: 0.1–10% w/w
- Lubricants: 0.05–7% w/w
Claim 6: Compound I as monohydrate.
Claim 7: obtainable by direct compression.
Claim 9: process prepared by direct compression (process claim).
Claim 11: disintegration performance constraint at 15–22°C ≤5 minutes.

Method claim scope: claim 8 ties formulation handling to a PAH indication

Claim 8 is a method-of-use claim that depends on the dispersible tablet of claim 1:

Disperse the dispersible tablet in aqueous media to create a suspension.
Administer the suspension to a patient needing treatment of pulmonary arterial hypertension.

This is not merely “treat PAH.” It requires the specific administration format tied to dispersing the claimed dispersible tablet.

Which parts of the claims create the biggest infringement and validity risk for generic or reformulation programs?

Highest-risk elements for design-around

“Dispersible tablet” form
If a challenger uses a non-dispersible tablet, a granule/sachet, or a different oral dosage form, they avoid the structural “dispersible tablet” frame. If they keep a dispersible tablet, they need to address other limitations.
Active ingredient identity: “Compound I” (including salts/solvates)
Any product using Compound I as claimed, even as a salt or solvate, is inside the active-ingredient boundary.
Direct compression manufacturing (claims 7 and 9)
Direct compression can be a route limitation. If infringement analysis views claim 7 as “obtainable by,” it may be harder to design around if manufacturing inevitably uses direct compression or if evidence shows direct compression is used. Claim 9 is an explicit process limitation, so it can be easier to avoid by manufacturing using a different process, depending on interpretation.
Numeric excipient ranges (claim 5)
Claim 5 is a quantitated formulation scaffold. A product with one or more excipient categories outside those ranges can weaken claim 5 coverage, though they may still fall into claim 1 (if dispersible tablet + Compound I + any acceptable excipients is present).
Performance disintegration requirement (claim 11)
A product that disintegrates more slowly than the ≤5 minute window at 15–22°C can avoid claim 11 without abandoning claim 1 coverage. Still, claim 11 is a dependent limitation, so avoiding it only matters if the plaintiff anchors on claim 11.
Monohydrate variant (claim 6)
If a product uses a different solvate/polymorph (or anhydrous form) and avoids monohydrate, it can escape claim 6. But again, claim 1 still covers Compound I generally (including salts/solvates), depending on how “monohydrate form” is treated as a separate embodiment rather than the only covered form.

Validity pressure points common to this claim architecture

Without external text of the specification and prosecution history, the likely validity battlegrounds for this style of claim set are:

Enablement and written description for broad “pharmaceutically acceptable excipients” while also offering numeric ranges and specific performance metrics.
Definiteness of “dispersible tablet,” “completely disintegrates,” and the temperature/time condition, especially if the specification defines method parameters.
Obviousness over known dispersible tablet excipient combinations and direct compression technology, with particular attention to whether the numeric ranges and disintegration window are shown to be critical.

How do the numeric excipient ranges in claim 5 constrain formulation design?

Claim 5 excipient band structure

Claim 5 defines a multi-component quantitative formulation window. This creates a combinatorial infringement surface:

Excipent class	Range in claim 5 (w/w, % of total tablet)	Scope implication
Fillers	40 to 85%	Large swing, but still constrains overall solids distribution
Disintegrants	0.5 to 20%	Constrains ability to hit fast disintegration
Glidants	0.1 to 5%	Constrains flow/processing additives used in direct compression
Acidifying agents	0.5 to 13%	May be used to stabilize, adjust pH, or improve mouth feel
Flavoring agents	1 to 15%	Constrains flavor load
Sweetening agents	0.1 to 10%	Constrains palatability formulation
Lubricants	0.05 to 7%	Constrains compaction and ejection behavior

Practical design-around implications (within the claim framework)

Staying within claim 1 without hitting claim 5: A generic developer can attempt to formulate a dispersible tablet with Compound I while placing one or more excipient classes outside claim 5 ranges. That reduces claim 5 risk but does not negate claim 1.
Avoiding disintegration constraint: If claim 11 is asserted, disintegration testing at 15–22°C becomes decisive. Formulation changes that slow disintegration beyond 5 minutes can avoid claim 11 while still being dispersible.
Avoiding monohydrate: Using a different solid form that is not monohydrate avoids claim 6. But claim 1 still covers Compound I generally as salt/solvate.

Does direct compression manufacturing create a route-to-infringement pathway under US 8,309,126?

Claims 7 and 9

Claim 7: “obtainable by using the method of direct compression.”
Claim 9: process claim: tablet is prepared by direct compression.

This architecture targets both:

Product-by-process style coverage (claim 7).
A distinct manufacturing infringement pathway (claim 9) if a challenger uses direct compression.

Litigation leverage points typically associated with route claims

For enforcement, the key issue becomes proof of manufacturing steps:

If a challenger documents direct compression use in batch records or validation protocols, it supports claim 9 coverage.
If a challenger uses roller compaction, wet granulation, or another route, they can attempt to avoid claim 9 while still risking claim 1 if the finished product is still a dispersible tablet.

What does the PAH method claim require, and can generic labeling changes avoid it?

Claim 8 elements

Claim 8 requires:

The dispersible tablet of claim 1 is dispersed in aqueous media to form a suspension.
The suspension is administered to a patient needing PAH treatment.

Labeling and “use” coverage

Changing indication language or label wording can matter in some infringement contexts, but claim 8 is written as an administration-for-treatment method. If the product is prescribed off-label for PAH and the act of administration satisfies the claim, method-of-use exposure can persist.
A generic that seeks labeling for PAH can raise direct method infringement risk.
A generic that carves out PAH may reduce risk, but enforcement can still focus on actual clinical practice if facts support the claimed method.

Orange Book status, Paragraph IV challenges, and settlement exposure for US 8,309,126

No Orange Book listing, NDA/BLA tie, or FDA reference product mapping is provided in the prompt. Without those identifiers, it is not possible to state:

whether US 8,309,126 is listed in the Orange Book,
whether any Paragraph IV certifications reference this patent,
whether there were settlements, consent decrees, or timing events linked to it.

Accordingly, the patent landscape below focuses on the claim-scope and design-around surfaces, not on Orange Book procedural history.

How does this patent compare with typical dispersible tablet and PAH solid-dose portfolios?

Common dispersible-tablet IP patterns

In US formulation families, dispersible/tablet IP often clusters into:

Composition of matter for a drug substance in a specific dosage form (or in a formulation matrix).
Dependent excipient-range claims to reinforce non-obviousness and tighten infringement.
Performance claims tied to disintegration/dispersibility kinetics.
Process claims based on direct compression or granulation methods.

US 8,309,126 matches this pattern strongly through:

Excipitor numeric ranges (claim 5),
a direct compression route (claims 7 and 9),
and a disintegration performance parameter (claim 11).

Common PAH method-of-use claims

For PAH drug candidates, method claims often cover:

dosage regimens,
route formats (oral suspension versus tablet),
and clinical endpoints or patient populations.

This patent’s method claim is relatively narrow in that it requires the suspension formed by dispersing the specific dispersible tablet.

What patent estate gaps does this claim set leave, and where might continuation or related patents exist?

Continuation/related coverage points suggested by the claim structure

Based on the dependent claim breadth, a family commonly extends into:

additional performance metrics (e.g., dispersibility time, mouth feel, dissolution),
additional solid forms (anhydrate, other hydrates/solvates, amorphous),
additional excipient-specific compositions,
dosage strength ranges and patient dosing regimens for PAH,
alternative manufacturing routes that still yield dispersible tablets.

This is not proof of existence, but it identifies where an estate typically concentrates follow-on claims when a foundational dispersible concept is secured.

Where enforcement may be limited

Claim 1 is broad but depends on “dispersible tablet” classification. If products are engineered to behave as suspensions via different mechanisms or devices, classification disputes can arise.
Claim 11 is narrow and requires a specific test window.
Claim 8 requires the suspension administration route and PAH use.

Key Takeaways

Core scope: US 8,309,126 protects a dispersible tablet containing Compound I (including salts/solvates) and pharmaceutically acceptable excipients, with strong dependent coverage via quantified excipient ranges, direct compression, and disintegration performance.
Highest infringement leverage: claims 1 and 5 (composition) plus claim 9 (process) are the most likely enforcement anchors if a generic keeps the same tablet category and excipient profile.
Design-around levers: change solid form (avoid monohydrate), move excipient categories outside claim 5 ranges, avoid meeting claim 11 disintegration criteria, and avoid direct compression to reduce claim 9 exposure.
Method-of-use risk: claim 8 ties PAH treatment to the act of dispersing the tablet into an aqueous suspension. Label carve-outs may reduce but not necessarily eliminate exposure depending on prescribing and actual administration.

FAQs

1) Does US 8,309,126 cover salts and solvates of “Compound I,” or only the free base?

Claim 1 explicitly covers “pharmaceutically acceptable salt or solvate thereof,” so salts/solvates are within the active-ingredient boundary.

2) If a product avoids claim 5 excipient ranges, can it still infringe US 8,309,126?

Yes. Claim 5 is dependent on claim 1. A product can avoid claim 5 while still meeting claim 1 if it remains a dispersible tablet with Compound I and pharmaceutically acceptable excipients.

3) Is the direct compression limitation only about manufacturing, or can it be enforced against finished product sales?

Both: claim 9 is a process claim (route-specific), while claim 7 is an “obtainable by” structure that can be argued as a product-by-process style limitation tied to manufacturing.

4) What role does the ≤5 minute disintegration test play in infringement strategy?

It is a dependent limitation (claim 11). It matters if enforcement is asserted under claim 11, and it provides a measurable testing endpoint at 15–22°C.

5) Can changing the indication wording on a label avoid liability under the PAH method claim?

It can reduce direct method-of-use exposure when the product is not used for PAH, but method claims can still be implicated by actual patient use that matches the claimed steps.

References (APA)

United States Patent No. 8,309,126. (claims as provided in the prompt).

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Patented / Exclusive Use	Submissiondate
Actelion	TRACLEER	bosentan	TABLET, FOR SUSPENSION;ORAL	209279-001	Sep 5, 2017	AB	RX	Yes	Yes	⤷ Start Trial	⤷ Start Trial	Y				⤷ Start Trial
>Applicant	>Tradename	>Generic Name	>Dosage	>NDA	>Approval Date	>TE	>Type	>RLD	>RS	>Patent No.	>Patent Expiration	>Product	>Substance	>Delist Req.	>Patented / Exclusive Use	>Submissiondate

Foriegn Application Priority Data
Foreign Country	Foreign Patent Number	Foreign Patent Date
	PCT/EP2005/005367	May 17, 2005

Country	Patent Number	Estimated Expiration	Supplementary Protection Certificate	SPC Country	SPC Expiration
Austria	E451914	⤷ Start Trial
Australia	2006248593	⤷ Start Trial
Brazil	PI0610187	⤷ Start Trial
Canada	2607098	⤷ Start Trial
>Country	>Patent Number	>Estimated Expiration	>Supplementary Protection Certificate	>SPC Country	>SPC Expiration

Details for Patent: 8,309,126

Which drugs does patent 8,309,126 protect, and when does it expire?

Summary for Patent: 8,309,126