United States Patent 12,558,330: Scope, Claims, and US Patent Landscape for a Stable Bumetanide Liquid
Patent US 12,558,330 claims a specific stabilized aqueous bumetanide composition and administering methods using tightly defined excipient levels, pH, and dosing ranges. The practical scope is narrow-to-moderate: it is constrained by composition percent ranges (especially bumetanide, CMC sodium, benzyl alcohol, potassium ion, and mannitol) and pH (6-8), then broadened only marginally by dependent claims that fix certain exemplified levels and by method claims that set dose volume and total bumetanide exposure.
What does US 12,558,330 claim in plain scope terms?
Claim 1: Core composition (the anchor)
Claim 1 defines a stable pharmaceutical composition that is an aqueous solution with the following quantitative constraints (wt/wt) and pH:
| Element |
Constraint in Claim 1 |
Claim language impact |
| Bumetanide |
~0.5 to 2.0% (wt/wt) |
Main active-range limitation |
| Low viscosity sodium carboxymethyl cellulose |
~0.1% (wt/wt) |
Single-point excipient constraint |
| Benzyl alcohol |
~0.5% (wt/wt) |
Single-point preservative constraint |
| Potassium ion |
~0.078 to 0.31% (wt/wt) |
Ionic strength constraint; likely from K salts |
| Mannitol |
~2 to 4% (wt/wt) |
Crystallization/osmotic stabilizer constraint |
| pH |
6 to 8 |
Range constraint on buffer system |
Scope consequence: A formulation that uses bumetanide outside 0.5-2% or omits/changes the CMC/bilzyl alcohol at materially different levels or uses a different pH regime does not fall within Claim 1 as written.
Dependent composition claims
- Claim 2: composition of Claim 1 where bumetanide is fixed at ~0.5% (wt/wt).
- Claim 3: composition of Claim 2 where mannitol is fixed at ~4% (wt/wt).
Scope consequence: Claim 2 and Claim 3 narrow to specific exemplified endpoints. These provide layered protection, but they do not expand Claim 1.
Method claims (treating edema with defined dosing)
- Claim 4: method of treating edema by administering a dose of 25 μL to 250 μL of the composition of Claim 1.
- Claim 5: dose is 100 μL.
- Claim 6: dose is 200 μL.
- Claim 7: subject has congestive heart failure or renal insufficiency.
- Claim 8: dose is delivered not more than 1 to 4 times over a six-hour period.
- Claim 9: subject does not receive more than about 10 mg bumetanide over a 12-hour period.
- Claim 10: subject has impaired gastrointestinal absorption of oral diuretic therapy or reduced intestinal motility prior to administering.
Scope consequence: These method constraints make the claims closer to a specific clinical use pattern and dosing regimen rather than any bumetanide administration for edema.
What is the effective “design space” covered by Claim 1?
Critical limiting features
To practice within Claim 1, an accused product must align on all of the following at once:
- Bumetanide concentration: 0.5 to 2.0% (wt/wt).
- CMC sodium: “low viscosity” and at about 0.1%.
- Benzyl alcohol: about 0.5%.
- Potassium ion: 0.078 to 0.31% (wt/wt).
- Mannitol: 2 to 4%.
- pH: between 6 and 8.
- Aqueous solution and “stable pharmaceutical composition.”
The most “replaceable” pieces from a formulation-development viewpoint are the specific excipient choices and their levels. The most “structural” limitation is the intersection of concentration bands and pH.
Sensitivity analysis (non-literal, but decision-relevant)
- Shifting bumetanide from 0.49% to 0.51% can determine literal infringement because the claim uses a numeric range.
- The CMC and benzyl alcohol are effectively single-point targets (“about 0.1%” and “about 0.5%”). Minor formulation changes can avoid literal capture unless they still qualify as “about.”
- Potassium ion is a unique limiter because it is specified as an ion concentration. Changing salt form, ionic strength, or using different buffering can move the product outside the 0.078 to 0.31% window.
Where does infringement likely occur: composition vs method?
Composition-focused infringement
- If a manufacturer sells a liquid product that matches the composition parameters, it can trigger composition claim exposure.
- If the product is sold for edema use, composition infringement does not depend on method claims.
Method-focused infringement
- A manufacturer or provider who administers a dosing regimen may face exposure on Claim 4-10, even if the exact product is sold with some labeling nuance, depending on jurisdiction and how “administering” is interpreted.
- Claim 10 ties use to patients with impaired oral absorption or reduced intestinal motility, which could narrow enforcement to specific clinical contexts.
How do the method claims constrain dosing and regimen?
Quantitative dose volume and total bumetanide
The method claims lock in administration patterns in two ways:
Volume constraint (Claim 4-6):
- Administer 25 to 250 μL (Claim 4).
- Fixed embodiments: 100 μL and 200 μL (Claims 5-6).
Exposure constraint (Claim 9):
- Total bumetanide exposure limited to about 10 mg over 12 hours.
Frequency constraint (Claim 8):
- Delivery not more than 1 to 4 times over a six-hour period.
Population and clinical context constraints
- Congestive heart failure or renal insufficiency (Claim 7).
- Impaired gastrointestinal absorption of oral diuretic therapy or reduced intestinal motility (Claim 10).
Scope consequence: Even if an administered volume falls into 25-250 μL, a patient context outside Claims 7 and 10 may reduce enforcement attractiveness for dependent claims, while Claim 4 still covers “treating edema” broadly.
What does the claims set imply for licensing and design-around?
Most likely “safe harbor” design-around levers
Given Claim 1’s tight formulation parameters, design-arounds typically aim to miss at least one element:
- Move bumetanide outside 0.5-2% (or ensure it is not “about” within that range).
- Replace benzyl alcohol or remove it, or shift preservative system such that it is not “about 0.5% benzyl alcohol.”
- Change the CMC grade to a non-“low viscosity” grade or shift level away from “about 0.1%.”
- Use different salt/buffer strategy that shifts potassium ion outside 0.078 to 0.31%.
- Adjust mannitol concentration outside 2-4%.
- Set pH outside 6 to 8.
What is harder to avoid
If a product is already a bumetanide liquid with:
- benzyl alcohol at about 0.5%,
- mannitol at about 2-4%,
- CMC at about 0.1%,
- and uses potassium for ionic strength within the claimed band,
then the claim becomes difficult to avoid without substantial reformulation.
US patent landscape: what claims like this typically block (and what they usually don’t)
Landscape segmentation
For a bumetanide stabilized aqueous formulation, US IP coverage typically clusters into four layers:
- Composition patents: specific aqueous excipient systems and stabilization approaches.
- Method patents: dosing volume/range, frequency, and patient subpopulations.
- Device/delivery patents: packaging, administration devices, or infusion apparatus.
- Data-driven exclusivities: regulatory exclusivities and exclusivity-like protections (not patent claims).
US 12,558,330 is primarily layer 1 plus layer 2: it locks down a stabilized formulation and an administration pattern.
Practical implications for competitors
- A generic or follow-on developer cannot rely only on changing the route (unless it changes the product form enough to remove Claim 1 limitations).
- If the clinical plan mirrors Claim 4-10, the method claims add a second barrier.
- If a competitor uses a different stabilizer set, it can often avoid Claim 1, but if they still achieve the same clinical dosing they may still encounter method claim exposure if the exact composition is used.
Claim-by-claim infringement map (product and use scenario lens)
| Scenario |
Potentially infringed claims |
Key matching requirements |
| Sell a liquid bumetanide product with exact excipient levels and pH window |
Claim 1 (and possibly 2-3) |
Hits all wt/wt ranges and pH 6-8 |
| Administer 100 μL of that exact product to treat edema |
Claim 4 and Claim 5 |
Dose volume 100 μL within edema treatment |
| Administer 200 μL with CHF/renal insufficiency context |
Claim 4, Claim 6, Claim 7 |
Dose volume and patient condition |
| Administer 25-250 μL in 1-4 doses over 6 hours, cap total bumetanide at ~10 mg/12 h |
Claim 4, Claim 8, Claim 9 |
Frequency, interval, and total exposure |
| Treat edema in a patient with impaired oral absorption and reduced intestinal motility using that composition |
Claim 4 and Claim 10 |
Clinical context tied to Claim 10 plus dose |
Key takeaways
- US 12,558,330 Claim 1 is the gatekeeper: the formulation must match a narrow aqueous bumetanide concentration window (0.5-2%), fixed CMC (about 0.1%), fixed benzyl alcohol (about 0.5%), defined potassium ion range (0.078-0.31%), mannitol (2-4%), and pH 6-8.
- Method claims add enforcement leverage through regimen details: dose volume (25-250 μL; 100 μL and 200 μL embodiments), frequency (1-4 times over six hours), and total exposure cap (about 10 mg over 12 hours), plus patient subpopulations (CHF/renal insufficiency; impaired oral absorption/reduced intestinal motility).
- Design-around is formulation-driven: avoiding Claim 1 requires missing at least one core quantitative limiter (bumetanide %, benzyl alcohol, CMC level/grade, potassium ion %, mannitol %, or pH).
- Even with a non-identical formulation, method claims can still matter if the administered product still meets Claim 1 parameters and the dosing regimen aligns with Claims 4-10.
FAQs
1. Which claim is most important for market exclusivity?
Claim 1, because it defines the stabilized aqueous bumetanide composition with tight concentration and pH limitations.
2. Do Claims 2 and 3 broaden coverage or narrow it?
They narrow Claim 1 to specific endpoints: bumetanide at about 0.5% (Claim 2) and mannitol at about 4% (Claim 3).
3. What dosing window is covered by the independent method claim?
Claim 4 covers administration of 25 μL to 250 μL of the Claim 1 composition.
4. What patient populations are explicitly covered in dependent claims?
Claim 7 covers congestive heart failure or renal insufficiency. Claim 10 covers patients with impaired GI absorption of oral diuretic therapy or reduced intestinal motility.
5. What is the hardest limitation to change if a product already exists?
The combination of benzyl alcohol (~0.5%), CMC sodium (~0.1%, low viscosity), potassium ion (0.078-0.31%), and pH (6-8), because each must align simultaneously for Claim 1.
References
[1] United States Patent US 12,558,330. Claims as provided in the user prompt.
