US Patent 5,914,122: Scope, claim map, and US landscape

US Patent 5,914,122 claims a tightly defined stable aqueous/alcoholic budesonide solution defined by (1) pH ≤ 6.0, (2) budesonide solubilized in water and/or specified alcohol solvents, (3) defined budesonide strength ranges, (4) optional stabilizers limited to sodium ethylenediaminetetraacetic acid (Na-EDTA) and/or cyclodextrins in narrow ranges, and (5) downstream rectal dosage forms (enema and rectal foam) that use the claimed stable solution as the “active ingredient.”

The enforceable scope is anchored on the composition definition; the process claims track the same formulation boundaries; and the dosage-form claims extend protection by requiring the active ingredient to be the claimed solution.

What does US 5,914,122 claim (core composition boundaries)?

Primary independent claim structure

The only independent claim in the set you provided is claim 1 (composition). Dependent claims then add stabilizers and numeric ranges, plus separate process and dosage-form families.

Claim 1 (composition, baseline)

Stable budesonide solution
pH ≤ 6.0
Budesonide is dissolved in a solvent selected from:
- water
- alcohol
- water/alcohol mixture
The alcohol is limited to:
- ethanol
- isopropanol
- propylene glycol

This claim does not, by itself, specify:

a minimum/maximum budesonide concentration (that appears in claim 3 and later),
stabilizer identity (that appears in claims 2, 5, 21, 22).

Stabilized compositions

Claim 2

Adds: stabilizing additive selected from:
- Na-EDTA
- cyclodextrins
- mixtures thereof
Still under pH ≤ 6.0 and same solvent/alcohol limitations as claim 1.

Claim 3

Adds numeric budesonide range:
- 0.001 to 0.1% by weight budesonide
Still under pH ≤ 6.0 and same solvent/alcohol limitations.

Claim 4

Adds numeric cyclodextrin range:
- 0.05 to 1.0% by weight cyclodextrins
Still under pH ≤ 6.0 and same solvent/alcohol limitations.

Claim 5 (most specific combination composition)

Requires both numeric ranges and stabilizer identities:
- budesonide 0.001 to 0.1% by weight
- Na-EDTA: 0.001 to 0.1% by weight
- cyclodextrins: 0.05 to 1.0% by weight
- or a mixture of said amounts of Na-EDTA and cyclodextrins
Still under pH ≤ 6.0 and same solvent/alcohol limitations.

Claim 21 and 22

These are narrower refinements of the “Na-EDTA + composition” and “both Na-EDTA + cyclodextrins + numeric ranges” concepts:
- Claim 21: pH ≤ 6.0; specified solvents/alcohols; budesonide solution with 0.001 to 0.1% Na-EDTA
- Claim 22: pH ≤ 6.0; specified solvents/alcohols; budesonide 0.001 to 0.1%; plus stabilizers in defined ranges:
- Na-EDTA 0.001 to 0.1%
- cyclodextrins 0.05 to 1.0%
- mixture of the stated amounts

Key point: Claims 1, 2, and 3 create a wide “solution” frame; claims 4 and 5 pull in numeric constraints that can materially narrow infringement for alternative formulations.

How do the process claims align with the composition limits?

Process family (claims 6–8)

Claim 6

Produces a stable budesonide-containing solution with pH ≤ 6.0
By:
1. dissolving budesonide in solvent selected from water, alcohol, water/alcohol
2. alcohol limited to ethanol, isopropanol, propylene glycol
3. adjusting pH to ≤ 6.0

Claim 7

Adds: adding stabilizing additive:
- Na-EDTA, or
- cyclodextrins, or
- mixture

Claim 8

Adds numeric ranges:
- solution comprises 0.001 to 1% by weight budesonide
- stabilizer selection with numeric ranges:
- Na-EDTA 0.001 to 1% by weight
- cyclodextrins 0.05 to 1.0% by weight
- mixture

Alignment to composition claims

The process claims track the same formulation boundaries as the composition claims.
For enforcement: a process is more likely to matter if manufacturing steps are documented (or if inducement claims are asserted), but infringement generally still hinges on whether the resulting product meets the claimed solution definition.

How far does protection extend into dosage forms?

Enema claims (claims 9–14)

Each enema claim is limited by product definition:

The enema comprises as the “active ingredient” a stable budesonide solution corresponding to the referenced solution claim.

Claim	Dosage form	Active ingredient limitation
9	Enema	Stable budesonide solution as in claim 1
10	Enema	Stable budesonide solution as in claim 2
11	Enema	Stable budesonide solution as in claim 3
12	Enema	Stable budesonide solution as in claim 4
13	Enema	Stable budesonide solution as in claim 5
14	Enema	Stable budesonide solution as in claim 6

Practical implication: any infringing enema must use a budesonide solution that satisfies the referenced claim’s numeric and ingredient limits.

Rectal foam claims (claims 15–20)

Similarly structured:

The foam comprises as active ingredient a stable aqueous budesonide solution corresponding to the cited claim.

Claim	Dosage form	Active ingredient limitation
15	Rectal foam	Stable aqueous budesonide solution as in claim 1
16	Rectal foam	Stable budesonide solution as in claim 2
17	Rectal foam	Stable budesonide solution as in claim 3
18	Rectal foam	Stable budesonide solution as in claim 4
19	Rectal foam	Stable budesonide solution as in claim 5
20	Rectal foam	Stable budesonide solution as in claim 6

Note on “stable aqueous budesonide solution”: Claim 15 explicitly says “stable aqueous,” but the underlying solution claim 1 includes water/alcohol mixtures. The foam claims incorporate the referenced solution definition, so the safe reading is that the foam uses the claimed stable solution, not an entirely separate foam-exclusive solvent system.

What claim elements are most likely to drive infringement or validity fights?

1) pH cutoff: “not exceeding 6.0”

This is the single strongest categorical limitation across claims.

If a product is formulated at pH > 6.0, it does not meet the “pH ≤ 6.0” element of claims 1, 2, 3, 4, 5, 6, 21, 22 and therefore cannot satisfy dependent claims tied to them.

2) Alcohol solvent identity

The only alcohols permitted are:

ethanol
isopropanol
propylene glycol

The “solvent selected from water, alcohol and water/alcohol mixture” also matters:

Using a different co-solvent or alcohol (or changing solvent logic) is a potential design-around because the claim language is identity-limited.

3) Budesonide concentration ranges

The numeric limits appear in:

claim 3: budesonide 0.001 to 0.1%
claim 5: budesonide 0.001 to 0.1%
claim 8 (process): budesonide 0.001 to 1%
claim 22: budesonide 0.001 to 0.1%

Thus, a formulation that uses the same pH and solvents but outside these ranges may avoid claims 3/5/21/22 depending on which claim family is asserted. If claim 1 is asserted, however, it does not require the budesonide numeric range.

4) Stabilizers: Na-EDTA and cyclodextrins

The stabilizers are limited to:

sodium ethylenediaminetetraacetic acid (and spelling variants)
cyclodextrins (generic plural)

And are bounded by:

claim 4: cyclodextrins 0.05 to 1.0%
claim 5: Na-EDTA 0.001 to 0.1% and cyclodextrins 0.05 to 1.0%
claim 8 (process): Na-EDTA 0.001 to 1%, cyclodextrins 0.05 to 1.0%
claim 22: Na-EDTA 0.001 to 0.1% and cyclodextrins 0.05 to 1.0%

A formulation using other stabilizers (buffers, antioxidants, polymeric stabilizers, different chelators) may be outside claims that require these specific stabilizers, but claim 1 could still be asserted if no stabilizer is required and the “stable budesonide solution” still meets pH and solvent limitations.

5) “Stable” is functional

“Stable” is inherently property-based. In practice, infringement can turn on stability testing methods and what “stable” means in the patent’s specification. Your claim set does not provide those definitions, so enforcement will likely lean on:

comparisons to stability data,
whether the formulation degrades outside expected thresholds under conditions described in the patent.

Overall patent landscape: what it likely covers in the US rectal budesonide space

Claim-driven coverage map

US 5,914,122 covers:

Solution: budesonide in water and/or specified alcohol solvents at pH ≤ 6.0, with optional stabilization by Na-EDTA and/or cyclodextrins in specified ranges.
Manufacturing: processes that dissolve and adjust pH to ≤6.0, optionally adding Na-EDTA/cyclodextrins within ranges.
Dosage forms: enemas and rectal foams that use those solutions as the active ingredient.

Likely competitive vectors

In the rectal budesonide segment, design-arounds typically cluster around the claim’s hard constraints:

pH > 6.0 (if stability can be achieved above the cutoff)
Different co-solvent system (replacement for ethanol/isopropanol/propylene glycol)
Different stabilizer system (no Na-EDTA and no cyclodextrins, or concentrations outside the ranges)
Outside the disclosed budesonide concentration windows for the claims that require those ranges

Potential “product form” carve-outs

Because the dosage form claims are tied to the “active ingredient” definition, foam or enema format alone does not avoid infringement if the active ingredient meets the claimed stable solution criteria. Conversely, alternative rectal formats are still at risk if they include the same claimed active ingredient solution and could be asserted under broader method/product theories depending on other patents.

Freedom-to-operate implications (claim-by-claim)

Below is a practical infringement-risk lens tied directly to the claim elements you supplied.

Risk tier A: High likelihood

Any budesonide rectal enema or rectal foam containing a solution that is:
- pH ≤ 6.0
- budesonide dissolved in water and/or ethanol/isopropanol/propylene glycol
- and uses Na-EDTA and/or cyclodextrins in-range
- with budesonide concentration within 0.001–0.1% for the claims that require that range.

This includes products matching claims 2/3/4/5/22.

Risk tier B: Medium likelihood

Products that hit pH ≤ 6.0 and the solvent identity, but:
- budesonide concentration is outside 0.001–0.1% (relevant to claims 3/5/22),
- stabilizer system excludes Na-EDTA/cyclodextrins (relevant to claims 2/4/5/7/8/22),
- but “stable” and the underlying solution definition still match claim 1.

In that case, claim 1 (and by extension claims 9/15) can still be asserted.

Risk tier C: Lower likelihood (design-around)

pH is consistently above 6.0 (blocks the pH element across the portfolio of claims).
alcohol system uses co-solvents outside the stated list (blocks solvent identity constraints for claims 1–6/21/22 and downstream dosage forms that incorporate them).
the product uses a different budesonide stabilization strategy that avoids Na-EDTA and cyclodextrins entirely and keeps the formulation outside the ranges where those elements are required.

Key takeaways

US 5,914,122 is built around a single, repeatable solution definition: budesonide dissolved in water and/or ethanol/isopropanol/propylene glycol at pH ≤ 6.0.
Stabilization is limited to Na-EDTA and/or cyclodextrins, with tight concentration ranges in several claims.
Enforcement can reach enemas and rectal foams because those dosage-form claims are drafted by referencing the claimed stable solution as the “active ingredient.”
The most direct design-arounds are raising pH above 6.0, using alcohols outside ethanol/isopropanol/propylene glycol, and/or eliminating Na-EDTA/cyclodextrins or moving outside the specified concentrations.

FAQs

1) Does the patent require both Na-EDTA and cyclodextrins?

No. Claims permit either:

Na-EDTA or cyclodextrins (claim 2), or
both together in defined ranges (claim 5 and claim 22).

2) Is “pH ≤ 6.0” required for both enema and rectal foam claims?

Yes. The enema (claims 9–14) and rectal foam (claims 15–20) claims depend on the underlying stable solution claims, which all require pH not exceeding 6.0.

3) If budesonide concentration is outside 0.001–0.1%, is infringement avoided?

For claims that include those ranges (claims 3/5/22), it can avoid those specific claims. But claim 1 does not require budesonide concentration ranges, so solutions still need to be checked against claim 1.

4) Can a rectal foam avoid the patent by using a different formulation vehicle for the foam base?

Not if the foam’s active ingredient still uses the claimed stable budesonide solution (as required by claims 15–20). Foam excipients may vary, but the active ingredient definition is the driver.

5) Do the process claims broaden the scope beyond the composition claims?

No. The process claims (claims 6–8) track the same solvent and pH ≤ 6.0 constraints, with optional stabilizers aligned to the same identities and ranges.

References

[1] United States Patent 5,914,122. “Stable budesonide solutions and rectal dosage forms.” (Claims text as provided in the prompt).

Foriegn Application Priority Data
Foreign Country	Foreign Patent Number	Foreign Patent Date
Germany	44 46 891	Dec 27, 1994

Country	Patent Number	Estimated Expiration	Supplementary Protection Certificate	SPC Country	SPC Expiration
Austria	168556	⤷ Start Trial
Canada	2205305	⤷ Start Trial
Germany	4446891	⤷ Start Trial
>Country	>Patent Number	>Estimated Expiration	>Supplementary Protection Certificate	>SPC Country	>SPC Expiration

Details for Patent: 5,914,122

Summary for Patent: 5,914,122