United States Patent 7,291,347 (O-Desmethyl Venlafaxine Succinate): Scope, Claim Construction, and US Patent Landscape

Executive summary: US Patent 7,291,347 claims an oral solid dosage form comprising O-desmethyl venlafaxine succinate (ODV-S) in tablet or capsule form, with specific strength ranges and specific drug-load (wt%) bands. The claim set is narrow on active ingredient identity (ODV-succinate) and dosage form class (oral tablet/capsule), while being broad on quantity selection within defined numeric ranges. For US generic and follow-on development, the practical design-around question is whether a product avoids: (1) ODV-succinate per se, (2) the tablet/capsule limitation, and (3) the wt% and per-unit mg windows recited.

What does US Patent 7,291,347 claim for O-desmethyl venlafaxine succinate?

Short answer: It claims ODV-succinate in oral tablets or oral capsules, with composition drug-load and dose-strength limitations.

Key claim elements (from the provided claims)

Core active ingredient

O-desmethyl venlafaxine succinate (ODV-succinate) is the required API identity.

Oral dosage form type

Tablet (Claim 1)
Capsule (Claim 2)

Numeric limitations

ODV-succinate content by weight in the dosage form:
- 30% to 50% (Claim 3)
- 32% to 44% (Claim 4)
- About 50% (Claim 5)
- About 44% (Claim 6)
ODV-succinate amount per dosage form:
- 15 mg to 350 mg (Claim 7)
- 10 mg to 1000 mg (Claim 8)
- 200 mg (Claim 9)

Claim dependency structure and what it narrows

Claims 1 and 2 establish the minimum scope: oral solid forms of the specified API.
Claims 3-6 are dependent on claims 1 or 2 and add drug-load bands.
Claims 7-9 are also dependent on claims 1 or 2 and add per-unit dose ranges, with Claim 9 being a specific strength.

Practical implication: a product that is an oral tablet/capsule with ODV-succinate but misses the wt% and/or mg windows may still fall within independent scope if claims 1/2 are asserted alone. However, most infringement theories for numeric composition patents focus on dependent claims, because those give more crisp quantitative targets.

How broad is the scope of US 7,291,347: tablet vs capsule, and what is still “within” the claims?

Short answer: The patent is moderately narrow by requiring both (i) ODV-succinate and (ii) oral tablet or capsule, while being flexible within the defined numeric ranges.

Tablet/capsule limitation

Claim 1: tablets only
Claim 2: capsules only
If a competitor uses different oral dosage forms (e.g., film, solution, suspension, chewable, orally disintegrating tablets not meeting “tablet” construction), they can try to avoid literal coverage of Claims 1/2. The boundary question becomes how “tablet” and “capsule” are interpreted in claim construction.

Dose load flexibility inside the numeric windows

By-weight range coverage:
- Claim 3 covers a broad 30%-to-50% segment.
- Claim 4 carves out 32%-to-44%, narrower but overlaps Claim 3.
- Claims 5 and 6 are “about” points. That phrasing can broaden beyond exactly 50% or 44%, but still constrains relative to a much wider range.
Per-unit mg ranges:
- Claim 7 (15-350 mg) sits inside Claim 8 (10-1000 mg).
- Claim 9 locks a specific strength at 200 mg.

Practical implication: If a formulation hits the tablet/capsule requirement and uses ODV-succinate in the same general strength class (e.g., 15-350 mg tablets), it is at risk for several dependent claim theories simultaneously.

What does “about” mean in claim language 7,291,347 for drug load and strength?

Short answer: “About” introduces tolerance. The legal effect depends on prosecution history and how a court construes the term, but the patent still defines the center points tightly enough to support infringement theories within practical manufacturing tolerances.

Where “about” appears

About 50% by weight (Claim 5)
About 44% by weight (Claim 6)

Where ranges appear (less subject to “about” tolerance)

30% to 50% (Claim 3)
32% to 44% (Claim 4)
15 mg to 350 mg (Claim 7)
10 mg to 1000 mg (Claim 8)

Design-around pressure points

To avoid Claims 3/4, a generic/formulation team would aim for drug-load outside those windows.
To avoid Claims 5/6, a team would avoid the “about” neighborhood around 50% and 44%. Because that is fact- and construction-dependent, the safest path is to choose a drug-load not plausibly within “about” of either point and also outside 30%-50% and 32%-44%.

Does US 7,291,347 require a specific formulation composition beyond ODV-succinate?

Short answer: In the provided claims, the only expressly required formulation limitation is the presence of ODV-succinate at specified weight fractions and per-unit mg amounts. The claims do not recite excipients, disintegrants, binders, coatings, release profiles, or specific tablet/capsule structures.

What is not claimed (based on provided claim text)

No explicit excipient categories
No dissolution or release parameter
No manufacturing method
No particle size specification
No coating type, enteric protection, or modified release

Practical implication: From a scope standpoint, the patent’s coverage can map onto many different excipient systems so long as the numeric content thresholds and dosage form type are satisfied.

What infringement theories are most likely under Claims 1 and 2 vs dependent Claims 3-9?

Short answer: Claims 1/2 provide a base theory for oral tablet/capsule products containing ODV-succinate; dependent claims add concrete quantitative constraints.

Base claim theories

If a product is a tablet containing ODV-succinate, it risks Claim 1.
If it is a capsule containing ODV-succinate, it risks Claim 2.
A plaintiff can assert Claim 1/2 even if the product misses drug-load bands, because Claims 1/2 do not (in your provided text) impose wt% or mg numeric limits.

Numeric dependent claim theories

For formulations within wt% and mg ranges, Claim 3/4 and Claim 7/8 and specific Claim 9 become relevant.
If the marketed strength is 200 mg, Claim 9 is a direct match.

Practical implication: Even if an ANDA or formulation strategy tries to shift dosage strength or concentration, it must address the possibility that an asserted independent claim still reads on the product class.

How many competitor products are covered based on the numeric wt% and strength windows?

Short answer: Coverage is determined by whether a product matches the required API identity and dosage form class, then whether it also matches at least one of the drug-load ranges and/or strength points.

Numeric “overlap map” for a formulation team

Limitation type	Claim(s)	Covered values	Overlap impact
Dose form type	1-2	tablet or capsule	Fundamental gatekeeper
Drug-load wt% band	3	30%-50%	Broad window
Drug-load wt% band	4	32%-44%	Subset of Claim 3
Drug-load wt% “about”	5	about 50%	Matches near upper end of Claim 3
Drug-load wt% “about”	6	about 44%	Matches inside Claim 4
Strength mg range	7	15-350 mg	Subset of Claim 8
Strength mg range	8	10-1000 mg	Broad strength umbrella
Specific strength	9	200 mg	Direct hit if marketed at 200 mg

What does the ODV-succinate specificity do to patent scope versus ODV free base or other salts?

Short answer: The claim is locked to O-desmethyl venlafaxine succinate. A product using a different salt (or free base) could seek to avoid literal infringement if it does not contain “O-desmethyl venlafaxine succinate” as claimed.

Practical implication: This is a high-leverage design-around axis:

If a competitor uses a different salt form (or forms a different chemical species during processing), the claim may not literally read.
If it is structurally the same API but differs by salt, the legal outcome turns on claim construction and how “comprising” interacts with salt interconversion and whether the product still “comprises” the claimed succinate form.

What is the broader US patent landscape around O-desmethyl venlafaxine succinate tablets/capsules?

Short answer: Based on the claim structure, US 7,291,347 is a typical “formulation composition claim” around a specific salt and delivery form. The landscape risk usually clusters into:

other patents covering ODV salt forms (different stoichiometries/crystal forms),
other patents covering specific solid-state forms (polymorphs/hydrates),
patents covering dosage strengths and drug-load bands,
patents covering coatings or modified-release versions (not explicit in your provided claims),
method-of-treatment patents, if the active is used as a therapeutic product.

However: you have supplied only the claim text, not the patent’s bibliographic details, assignee, filing history, or cited references. Without those, a complete, accurate mapping of co-pending/related US patents and their exact claim scopes cannot be produced here.

When does US 7,291,347 expire and how does exclusivity interact with generic entry?

Short answer: Expiration timing depends on the patent’s filing date and any terminal disclaimers, and exclusivity depends on FDA marketing exclusivity of the reference drug for the relevant NDA/RLD.

However: the expiration date, reference-listed drug, and Orange Book status are not provided, and the claim text alone is insufficient to determine enforceable end dates, term adjustments, or exclusivity overlap.

How strong is the patent estate implied by these claims for litigation and licensing?

Short answer: The claims are strong in enforcement leverage because they are:

specific to ODV-succinate (identity gate),
specific to tablet/capsule (dosage form gate),
anchored to concrete numeric constraints (litigation-ready metrics).

Weakness vector: scope breadth is limited by:

dosage form type (tablet/capsule only),
reliance on API identity (salt form specificity),
dependent claim quantitative requirements for added coverage beyond Claims 1/2.

What generic entry risks exist for an ANDA targeting ODV-succinate tablets or capsules?

Short answer: Risk is highest when the ANDA product matches:

ODV-succinate identity,
the marketed dosage form (tablet or capsule),
and, in particular, the numeric wt% and strength bands, including 200 mg.

High-risk product profiles

Tablet or capsule with ODV-succinate at wt% within 30%-50%.
Strengths in the 15-350 mg band.
A 200 mg strength product.

Lower-risk profiles (still must address Claims 1/2)

Oral dosage form not considered a “tablet” or “capsule.”
Different salt form (not ODV-succinate).
Drug-load and per-unit dose chosen to fall outside the numeric bands.
These strategies may still trigger Claims 1/2 if the product is still a tablet/capsule comprising ODV-succinate.

What are the main design-around strategies against this claim set?

Short answer: Three practical axes: (1) dosage form class, (2) salt identity, (3) numeric drug load and unit strength.

1) Avoid tablet/capsule

Use a different oral format not captured by “tablet” or “capsule.”
If the competitor uses “tablet” but a different structural category still litigated as a tablet, the design-around can fail.

2) Avoid ODV-succinate

Use a different salt form or free base.
If marketed as the succinate salt or contains succinate as the active salt, literal risk remains.

3) Avoid numeric bands

Choose wt% outside 30%-50% and also outside the “about” neighborhoods of 44% and 50%.
Choose per-unit mg outside 10-1000 mg and outside the 15-350 mg range.
If Claims 1/2 are asserted alone, missing numeric constraints may not fully avoid liability.

Key Takeaways

US Patent 7,291,347 claims oral tablet/capsule products comprising O-desmethyl venlafaxine succinate.
Dependent claims add tight quantitative limits on ODV-succinate wt% (30%-50%, 32%-44%, about 50%, about 44%) and per-unit strength (15-350 mg, 10-1000 mg, and a specific 200 mg).
The highest litigation and licensing leverage comes from matching the API identity and dosage form class, then landing inside the numeric ranges.
Generic design-around must address the possibility that Claims 1/2 may cover a product even if dependent numeric constraints are missed.

FAQs

1) Can a capsule product avoid infringement if it misses the drug-load wt% range but still uses ODV-succinate?
It may still fall within Claim 2 if the product is an oral capsule comprising ODV-succinate.

2) Is “200 mg” required to infringe US 7,291,347?
No. Claim 9 is a dependent claim on a specific strength, but the patent also has broader ranges and independent tablet/capsule coverage.

3) Do the claims require any specific excipients or release profile?
In the provided claims, no. The limitations focus on API identity, dosage form type, and numeric content.

4) Would using a different salt of O-desmethyl venlafaxine avoid the patent?
Potentially, because the claims specify O-desmethyl venlafaxine succinate. The legal outcome turns on whether the competing product literally contains that salt form as claimed.

5) Are oral solutions or suspensions covered by the claims?
Not on the provided language, because the claims specify tablet or capsule dosage forms.

References (APA)

Provided: US Drug Patent 7,291,347 claim text (user-supplied).

Country	Patent Number	Estimated Expiration	Supplementary Protection Certificate	SPC Country	SPC Expiration
Argentina	032671	⤷ Start Trial
Argentina	082076	⤷ Start Trial
Austria	369330	⤷ Start Trial
Australia	2002250058	⤷ Start Trial
Brazil	0207157	⤷ Start Trial
>Country	>Patent Number	>Estimated Expiration	>Supplementary Protection Certificate	>SPC Country	>SPC Expiration

Details for Patent: 7,291,347

Summary for Patent: 7,291,347