United States Patent 5,476,669: Scope, Claim Architecture, and US Patent Landscape (H. pylori + Bismuth + Tetracycline/Penicillin + Metronidazole + Acid Suppression)
US Drug Patent: US 5,476,669
Core subject matter: Methods for eradication of Campylobacter pylori (Helicobacter pylori) using bismuth compound + tetracycline or penicillin + metronidazole, with acid suppression (optionally pre-dosing) to improve ulcer healing and reduce recurrence for gastric and duodenal ulcers.
Claim set (as provided): Claims 1-34, centered on (i) prevention of recurrence and (ii) treatment/healing with timing-dependent acid suppression and then eradication therapy.
What is the claim center of gravity in US 5,476,669?
The patent is drafted as combination-therapy method claims with a repeating “backbone”:
- Patient condition: gastric ulcer or duodenal ulcer associated with Campylobacter pylori (H. pylori).
- Eradication regimen:
- Bismuth compound (pharmaceutically acceptable)
- First antibiotic: tetracycline or penicillin
- Second antibiotic: metronidazole
- Acid suppressant: an optional or integrated component depending on claim.
- Timing element: some dependent claims require acid suppression for 3 to 28 days followed by the bismuth/antibiotic combination.
High-level structural split
- Claims 1, 10, 19, 27: define the treatment/prevention methods and establish the bismuth + tetracycline/penicillin + metronidazole core.
- Claims 2-9, 11-18, 20-26, 28-34: narrow by adding and specifying acid suppressant type and duration/timing.
What does Claim 1 actually cover (and what does it exclude)?
Claim 1 is the “prevent recurrence of gastric ulcer” independent claim and it includes:
Method step(s):
- Administer to a patient with gastric ulcer disease associated with H. pylori:
- H. pylori infection eradicating amounts of:
- a pharmaceutically acceptable bismuth compound
- first antibiotic: tetracycline and penicillins (group)
- second antibiotic: metronidazole
What Claim 1 does not require:
- It does not require any acid suppressant.
- It does not require a specific treatment duration or sequential timing.
- It does not require particular patient subtypes beyond ulcer associated with H. pylori.
Practical implication for scope: Claim 1 reads as a method claim to prevent gastric ulcer recurrence using a bismuth + tetracycline/penicillin + metronidazole eradication scheme, without needing acid suppression.
How do dependent Claims 2-9 expand scope via acid suppression?
Claim 2 adds: a step of administering a gastric acid suppressant for a predetermined length of time.
Claim 3 defines the timing: 3 to 28 days, followed by administration of the bismuth compound/antibiotics combination.
Claims 4-9 specify classes of acid suppressants:
- Claim 4: histamine2 receptor antagonist (H2RA)
- Claim 5: benzimidazole
- Claim 6: lansoprazole or omeprazole (PPI subclass within benzimidazole)
- Claim 7: prostaglandin
- Claim 8: proton pump inhibitor (PPI) (broad class)
- Claim 9: K/Na ATP-ase inhibitor (potassium/hydrogen ATPase inhibitor class)
Scope effect
- The dependent set creates an overlay of protected combinations where eradication therapy is paired with (or sequenced after) acid suppression.
- Claims 5-6 further pin down a subset of PPIs to lansoprazole/omeprazole.
What does Claim 10 broaden to (treatment with healing and eradication sequence flexibility)?
Claim 10 is an independent “treat gastric ulcer” claim and differs from Claim 1 in two ways:
- It requires acid suppressant for symptomatic relief and ulcer epithelialization.
- It permits the eradication step to start before or during the acid suppression/ulcer-healing window.
Claim 10 wording (as provided) requires:
- Administer acid suppressant effective to obtain:
- symptomatic relief
- ulcer epithelialization
- Before or during administering eradication amounts of:
- bismuth compound
- first antibiotic: tetracycline or penicillin group
- second antibiotic: metronidazole
Claim 11-18 then add the same timing and acid-suppressant class logic as in Claims 2-9:
- Claim 12: timing 3 to 28 days then eradication combo
- Claims 13-18: H2RA, benzimidazole (lansoprazole/omeprazole), prostaglandin, PPI, K/Na ATP-ase inhibitor
Scope effect: Claim 10 allows overlap or sequencing flexibility (“before or during”) rather than strictly requiring acid suppression first (as the dependent timing claims do).
Is the duodenal ulcer portion a straight mirror of gastric?
Yes in claim logic and structure.
Claim 19 (prevent recurrence of duodenal ulcer)
- Requires eradication regimen only:
- bismuth compound + tetracycline/penicillin + metronidazole
- Plus it includes a step of administering gastric acid suppressant for a predetermined length of time (unlike Claim 1, which is gastric recurrence prevention without acid suppressant).
Claims 20-26 (duodenal dependent refinements)
- Claim 20: timing 3 to 28 days, followed by eradication combo
- Claims 21-26: acid suppressant classes:
- H2RA
- benzimidazole (Claim 23: lansoprazole or omeprazole)
- prostaglandin
- PPI
- K/Na ATP-ase inhibitor
Claims 27-34 (duodenal treatment with epithelialization)
- Claim 27: requires acid suppressant for symptomatic relief and ulcer healing, with eradication amounts of bismuth/antibiotics “before or during” administration; also requires healing and recurrence prevention.
- Claims 28-34: add timing and specify acid suppressant classes similarly (including lansoprazole/omeprazole in Claim 31).
What is the practical “infringement map” implied by these claims?
Below is the effective claim boundary as drafted (based on your claim text):
Minimum elements for the “eradication core”
- Patient with gastric ulcer or duodenal ulcer associated with H. pylori
- Administration of H. pylori eradication amounts of:
- bismuth compound
- tetracycline or penicillin group
- metronidazole
Additional elements that trigger narrower dependent claims
- An acid suppressant is administered, for predetermined length (and for some claims, specifically 3-28 days prior to eradication combo).
- Acid suppressant must fit one of the enumerated classes:
- H2RA
- benzimidazole (and then explicitly lansoprazole/omeprazole)
- prostaglandin
- PPI
- K/Na ATP-ase inhibitor
Overlapping coverage
- Claims cover multiple ulcer types and both:
- recurrence prevention
- treatment/healing and recurrence prevention (explicit in Claim 27)
How tight are the claim terms? (drafting precision and leverage points)
1) “First antibiotic selected from tetracycline and penicillins”
- This is a two-part selector:
- tetracycline
- or any penicillin within the “penicillins” group
- That broadens the antibiotic substitution space beyond tetracycline alone.
2) “Bismuth compound”
- The claims do not enumerate specific bismuth salts in the text provided.
- They require only “pharmaceutically acceptable bismuth compound,” which typically covers common bismuth salts used in H. pylori regimens.
3) “Acid suppressant” class enumerations
- Dependent claims list multiple classes and specific examples:
- lansoprazole or omeprazole appear as a concrete subset within benzimidazoles.
- The breadth of listing (H2RA, prostaglandins, PPIs, K/Na ATP-ase inhibitors) creates multiple “entry points” for accused regimens.
4) Timing architecture
- Dependent claims require 3-28 days then eradication combo.
- Independent treatment claims allow eradication “before or during” acid suppression.
This combination of class-based acid suppression plus timing creates layered claim coverage that is harder to design around than an isolated sequence requirement.
What is the likely patent landscape structure around US 5,476,669?
Landscape buckets for H. pylori ulcer regimens
In the US, H. pylori eradication and ulcer-healing regimens generally cluster into:
- Triple therapy / multi-drug combinations (bismuth-based, antibiotic-based, acid-suppression-based)
- Acid suppression modalities (H2RA, PPIs, K/Na ATP-ase inhibitors) and sequencing for healing
- Specific antibiotic substitutions in established regimens
- Methods of preventing recurrence versus initial eradication
US 5,476,669 sits squarely at the intersection of bismuth-based multi-antibiotic eradication plus acid suppression with a timing window in some dependent claims.
Why the timing and acid-suppressant class matter commercially
The claims allow multiple litigation pathways:
- If an accused regimen uses the same eradication core (bismuth + tetracycline/penicillin + metronidazole), then:
- Claim 1 and its duodenal mirror (Claim 19 is different since it includes acid suppression) become the focus.
- If an accused regimen also uses acid suppression, dependent claims become relevant:
- Claim 3 and Claim 12 and Claim 20 and Claim 28 (3-28 day pre-treatment window)
- Claim 6/15/23/31 (lansoprazole or omeprazole)
- Claim 4/13/21/29 (H2RA)
- Claim 7/16/24/32 (prostaglandin)
- Claim 8/17/25/33 (PPI)
- Claim 9/18/26/34 (K/Na ATP-ase inhibitor)
Where are the likely “hot zones” for freedom-to-operate (FTO)?
Even without knowing the inventors/assignee or the file history, the claim structure indicates three FTO pressure points:
Hot zone A: bismuth + tetracycline (or penicillin) + metronidazole eradication
- If the regimen’s eradication core matches this exact structure, Claim 1 (gastric recurrence prevention) is a direct line.
Hot zone B: acid suppression pairing
- If acid suppression is used, especially with:
- benzimidazole / lansoprazole / omeprazole
- or a listed class matching PPIs/H2RA/prostaglandin/K/Na ATP-ase inhibitor
- then dependent claims may read on the regimen.
Hot zone C: sequencing and 3-28 day window
- Many regimens in practice may start antibiotics alongside acid suppression.
- The dependent timing claims narrow to 3-28 days, which can become decisive if a competitor markets or prescribes a similar sequential approach.
Claim-by-claim scope matrix (what each claim adds)
| Claim |
Ulcer type / goal |
Acid suppressant required? |
Acid suppression specifics |
Eradication core (always) |
| 1 |
Gastric ulcer recurrence prevention |
No |
N/A |
Bismuth + tetracycline or penicillin + metronidazole |
| 2 |
Gastric recurrence prevention |
Yes |
Type unspecified |
Same as Claim 1 |
| 3 |
Gastric recurrence prevention |
Yes |
3-28 days then eradication combo |
Same |
| 4 |
Gastric recurrence prevention |
Yes |
H2RA |
Same |
| 5 |
Gastric recurrence prevention |
Yes |
benzimidazole |
Same |
| 6 |
Gastric recurrence prevention |
Yes |
lansoprazole or omeprazole |
Same |
| 7 |
Gastric recurrence prevention |
Yes |
prostaglandin |
Same |
| 8 |
Gastric recurrence prevention |
Yes |
PPI |
Same |
| 9 |
Gastric recurrence prevention |
Yes |
K/Na ATP-ase inhibitor |
Same |
| 10 |
Gastric ulcer treatment + healing + eradication |
Yes |
Effective for symptomatic relief and epithelialization; “before or during” eradication |
Same eradication core |
| 11 |
Gastric treatment |
Yes |
Adds predetermined length |
Same |
| 12 |
Gastric treatment |
Yes |
3-28 days then eradication combo |
Same |
| 13 |
Gastric treatment |
Yes |
H2RA |
Same |
| 14 |
Gastric treatment |
Yes |
benzimidazole |
Same |
| 15 |
Gastric treatment |
Yes |
lansoprazole or omeprazole |
Same |
| 16 |
Gastric treatment |
Yes |
prostaglandin |
Same |
| 17 |
Gastric treatment |
Yes |
PPI |
Same |
| 18 |
Gastric treatment |
Yes |
K/Na ATP-ase inhibitor |
Same |
| 19 |
Duodenal recurrence prevention |
Yes |
Predetermined length |
Same eradication core + includes acid suppression step |
| 20 |
Duodenal recurrence prevention |
Yes |
3-28 days then eradication combo |
Same |
| 21 |
Duodenal recurrence prevention |
Yes |
H2RA |
Same |
| 22 |
Duodenal recurrence prevention |
Yes |
benzimidazole |
Same |
| 23 |
Duodenal recurrence prevention |
Yes |
lansoprazole or omeprazole |
Same |
| 24 |
Duodenal recurrence prevention |
Yes |
prostaglandin |
Same |
| 25 |
Duodenal recurrence prevention |
Yes |
PPI |
Same |
| 26 |
Duodenal recurrence prevention |
Yes |
K/Na ATP-ase inhibitor |
Same |
| 27 |
Duodenal treatment + healing + recurrence prevention |
Yes |
Effective for relief and epithelialization; “before or during” eradication |
Same eradication core |
| 28 |
Duodenal treatment |
Yes |
3-28 days then eradication combo |
Same |
| 29 |
Duodenal treatment |
Yes |
H2RA |
Same |
| 30 |
Duodenal treatment |
Yes |
benzimidazole |
Same |
| 31 |
Duodenal treatment |
Yes |
lansoprazole or omeprazole |
Same |
| 32 |
Duodenal treatment |
Yes |
prostaglandin |
Same |
| 33 |
Duodenal treatment |
Yes |
PPI |
Same |
| 34 |
Duodenal treatment |
Yes |
K/Na ATP-ase inhibitor |
Same |
What actionable conclusions follow from the scope?
1) The patent is “bismuth-based eradication + antibiotic pairing + optional acid suppression timing.”
The claims are not about novel formulations; they are about method-of-use: combining existing drug classes in a defined therapeutic sequence for ulcer recurrence prevention or healing in H. pylori-associated ulcer disease.
2) Acid suppression is a critical differentiator for dependent claims.
If a regimen omits acid suppressants entirely:
- coverage still exists for at least gastric recurrence prevention via Claim 1.
If a regimen includes acid suppressants:
- the specific class matters for dependent claims.
3) Lansoprazole and omeprazole are explicit anchors.
Where acid suppression is a benzimidazole/PPI, Claims 6 and 15 and 23 and 31 narrow to lansoprazole or omeprazole.
Key Takeaways
- US 5,476,669 claims H. pylori eradication methods for gastric and duodenal ulcers using bismuth compound + (tetracycline or penicillin) + metronidazole.
- Claims expand protection by adding gastric acid suppressant steps, with dependent claims requiring 3 to 28 days followed by the eradication combination.
- The acid-suppressant dependent claims cover multiple classes, including H2RAs, PPIs, prostanglandins, K/Na ATP-ase inhibitors, and specifically lansoprazole or omeprazole.
- The patent’s scope creates layered coverage: eradication-core claims (especially Claim 1 and the duodenal analog structure) plus broader method claims when acid suppression and sequencing are used.
FAQs
1) Does US 5,476,669 claim a specific bismuth salt?
No. The claims require a “pharmaceutically acceptable bismuth compound,” without specifying a particular salt in the text provided.
2) Can tetracycline be replaced by any penicillin?
The claims state the first antibiotic is selected from the group “tetracycline and penicillins,” so they include the penicillin group rather than a single penicillin.
3) Is acid suppression mandatory for all claims?
No. Claim 1 omits acid suppression; other claims add it, including those focused on gastric and duodenal treatment and multiple dependent refinements.
4) What timing requirement appears in dependent claims?
Several dependent claims require acid suppressant administration for three to twenty-eight days, followed by the bismuth/antibiotics combination.
5) Which acid suppressants are explicitly called out by name?
Lansoprazole and omeprazole are explicitly named as the benzimidazole/PPI subset in the dependent claims.
References
[1] United States Patent and Trademark Office (USPTO). US 5,476,669.
