Scope and Claims Breakdown for US Patent 12,458,591 (Naloxone Intranasal, 100 µL, 13–66 mg/mL HCl-Equivalent) and the US Patent Landscape

Executive summary

US Patent 12,458,591 claims a US method-of-treatment for opioid overdosing using an intranasal naloxone formulation dosed as 100 µL total with naloxone HCl-equivalent concentration of 13 to 66 mg/mL (and multiple dependent concentration subranges), delivered as a nasal spray / mucoadhesive / mucosal atomizer in single- or two-nostril dosing arrangements, optionally with additional IM/IV naloxone co-administration. The claim set is narrowly anchored to: (i) route (intranasal), (ii) volume (100 µL), and (iii) concentration window expressed as naloxone HCl-equivalent per ml of application fluid, plus delivery-device and diluent constraints. The strongest enforcement leverage is against generics or next-gen products that match the exact dosing math (100 µL and the claimed mg/mL HCl-equivalent range) and the treatment method framing (“treating opioid overdosing”).

What exactly does US Patent 12,458,591 claim for intranasal naloxone overdosing treatment?

Core independent claim (Claim 1) is a method of treating opioid overdosing by intranasally administering 100 µL of an intranasal pharmaceutical dosage form containing naloxone (or pharmaceutically acceptable salt, limited in practice by the concentration conversion to naloxone HCl-equivalent) dissolved in an application fluid, where the final concentration is between 13 mg naloxone HCl per ml application fluid and 66 mg naloxone HCl per ml application fluid.

Claim 1 anchor points (litigation-ready limitations)

Method category: method of treating opioid overdosing (not composition per se).
Patient: “patient in need thereof” (standard treatment method language).
Route: intranasal administration.
Total administered volume: 100 µL.
Actives: naloxone or pharmaceutically acceptable salt.
Form: “intranasal pharmaceutical dosage form comprising… dissolved in an application fluid.”
Concentration window: 13–66 mg/mL (naloxone HCl-equivalent).

Dependent concentration claims (scope partitioning)

Claims 2–5 and 6–10 carve concentration subranges:

Claim 2: 20–60 mg/mL (HCl-equivalent)
Claim 3: 20–50 mg/mL (HCl-equivalent)
Claim 4: 18–20 mg/mL (HCl-equivalent)
Claim 5: 13–16 mg/mL (HCl-equivalent)
Claim 6: exactly 66 mg/mL
Claim 7: exactly 40 mg/mL
Claim 8: exactly 20 mg/mL
Claim 9: exactly 15 mg/mL
Claim 10: exactly 13 mg/mL

These are precision “infringement magnets.” If a competitor’s label dosing uses the same concentration conversion, it can land directly in one of the dependent claims even if not in claim 2/3/5.

How does the 100 µL dose translate into naloxone amount (mg) for infringement analysis?

Because Claim 1 fixes volume (100 µL = 0.1 mL), the claimed concentration range maps to a naloxone HCl-equivalent amount per dose:

Minimum: 13 mg/mL × 0.1 mL = 1.3 mg naloxone HCl-equivalent per 100 µL
Maximum: 66 mg/mL × 0.1 mL = 6.6 mg naloxone HCl-equivalent per 100 µL

Exact concentration dependent claims map similarly:

Claim subrange	Concentration (mg/mL, HCl-equiv.)	Dose in 100 µL (mg HCl-equiv.)
Claim 5	13–16	1.3–1.6
Claim 4	18–20	1.8–2.0
Claim 2	20–60	2.0–6.0
Claim 3	20–50	2.0–5.0
Claim 6	66	6.6
Claim 7	40	4.0
Claim 8	20	2.0
Claim 9	15	1.5
Claim 10	13	1.3

Practical infringement reading: a product that administers a total of 100 µL intranasally and delivers naloxone at a concentration falling in the claimed mg/mL HCl-equivalent range (with the same application-fluid concept) sits inside the claim geometry.

What delivery formats and administration patterns broaden or narrow claim coverage?

Beyond concentration, the remaining dependent claims specify delivery formats and dosing-unit geometry.

Dose unit geometry (single- vs two-nostril administration)

Claim 12: dosage form provided in a single dosing unit or two dosing units, depending on one nostril vs two nostrils administration.
Claims 16–17 (connected to Claim 13 delivery format):
- Claim 16: single dosing unit for one nostril
- Claim 17: two dosing units for two nostrils, with each dosing unit comprising half of the naloxone in the dosage form

Impact: the patent does not require a one-nostril-only regimen. It anticipates split dosing consistent with many nasal emergency products (though it still keeps the total administration volume at 100 µL, as required by Claim 1).

Device / dosage form language

Claim 13: dosage form is one of:
- nasal spray
- nasal mucoadhesive dosage form
- mucosal atomizer device

Impact: enforcement is not limited to one dispenser type. A mucoadhesive gel-type concept is explicitly within scope, as is atomizer technology.

Diluent constraint: water or aqueous saline

Claim 11: application fluid is water or aqueous saline solution.

If a competitor uses a different solvent system (non-water, non-saline), Claim 11 may not be met, but Claim 1 can still be asserted unless it is construed as implicitly requiring these fluids (Claim 1 itself only requires “application fluid”; Claim 11 narrows).

Active-only composition limitation

Claim 14: naloxone is the only pharmaceutically active compound in the dosage form.

This narrows designs that include combination actives (for example, additional drugs or antagonists). It is also relevant to “reformulation” attempts that add excipients with active pharmacology (not merely inactive excipients).

Does US 12,458,591 cover co-administration with IM/IV naloxone?

Yes, via dependent Claim 15:

Claim 15: dosage form is co-administered with an intramuscular and/or intravenous naloxone product.

Scope effect: claim coverage supports treatment regimens where intranasal naloxone is an initial step while IM/IV escalation occurs. This is useful in litigation because it addresses standard emergency workflows where responders may administer multiple routes over time.

What is the likely claim construction risk around “naloxone HCl per ml application fluid”?

The concentration is always expressed as mg naloxone HCl per ml application fluid, including where naloxone free base or other salts are used. That creates two claim-construction pressure points:

Equivalency calculation: “equivalent to” language implies a conversion factor (molecular weight or salt factor). In dispute, the competitor’s analytically stated concentration must be mapped to HCl-equivalent.
“Application fluid” boundary: the concentration must be in the solution in the application fluid. If a competitor’s product uses multi-phase media, suspensions, or different dispersion concepts, it may try to argue the “dissolved in” aspect is not met. The claim language says “dissolved,” which is a narrower phrasing than “containing.”

These issues matter for designing around the claim and for validating infringement theories.

What patents and patent types typically sit in the same landscape as a 100 µL intranasal naloxone method claim?

A method-of-treatment claim like this usually coexists with other patent families across four buckets:

Drug product formulation patents (composition, concentration, excipients, pH/salt form, viscosity, device compatibility)
Device and delivery mechanism patents (atomizer, spray geometry, mucoadhesive delivery, metering mechanisms)
Method-of-use patents (treatment steps, dose volume, timing, co-administration)
Concentration window refinements (exact mg/mL targets, narrow subranges like 13–16, 18–20, or exact 20/40/66 mg/mL)

Business implication: even though Claim 1 is a method claim, infringement can be enabled by product attributes (concentration and dosing volume) that are often disclosed in drug product composition patents and device patents. A competitor cannot avoid the method claim merely by changing the packaging; it must change the dosing geometry and/or the claimed concentration equivalency.

How does US 12,458,591 compare to naloxone intranasal dose standards on the market (US)

Your claim text references concentrations such as 20 mg/mL and dose amounts of 2.0 mg in 100 µL (because 0.1 mL × 20 mg/mL = 2.0 mg). Market-relevant products frequently use fixed-dose nasal delivery schemes, which makes exact concentration and delivered volume central for “matches.”

Key comparison axis for any competitor design:

Total intranasal delivered volume equals 100 µL (not per nostril).
Naloxone concentration equals 13–66 mg/mL in HCl-equivalent terms.
Delivery format fits at least one of: nasal spray, mucoadhesive, or mucosal atomizer.

If a competitor’s labeled dosing delivers a different total volume, or uses a concentration outside 13–66 mg/mL HCl-equivalent, it can fall outside Claim 1 while still potentially facing formulation or device patents.

Which potential generic or follow-on products are most exposed under the 12,458,591 claim structure?

The claim structure implies highest exposure for products that:

Administer total 100 µL intranasally.
Deliver naloxone at a concentration within 13–66 mg/mL HCl-equivalent.
Use water or aqueous saline as the application fluid and provide naloxone as the only active.
Implement a delivery format captured by “nasal spray,” “nasal mucoadhesive dosage form,” or “mucosal atomizer.”

Design-around candidates that reduce risk are those that:

shift to a non-water/non-saline application fluid (helps for Claim 11 but may not defeat Claim 1),
use combination actives (helps Claim 14),
alter total volume away from 100 µL, or
use a concentration outside the windows (helps Claim 1 and all concentration dependents).

How strong is the infringement position if a product matches the volume and concentration but differs in device?

Claim 1 does not require a specific device type. It only requires an intranasal pharmaceutical dosage form and the dosing geometry. Dependent Claim 13 then narrows to specific delivery formats.

Litigation reading:

To assert Claim 1, it is enough that the accused product performs intranasal administration with 100 µL total and 13–66 mg/mL HCl-equivalent in the application fluid.
Device differences may still be irrelevant if Claim 1 is met.
Device differences matter if the infringement case depends on Claim 13.

What matters most for Paragraph IV-style challenges or generic entry risk under a method-of-treatment claim?

Method-of-treatment claims are often treated differently than product claims because the inducement and practice pathways rely on how the product is marketed, labeled, and used.

For a product attempting to enter before resolution:

The key question is whether the generic’s formulated dose and labeling lead to practicing the claimed method, especially:
- 100 µL total intranasal volume,
- naloxone HCl-equivalent concentration in the claimed windows,
- route is intranasal and the treatment is opioid overdose.

Even if a generic argues it does not “infringe” because it targets a different concentration or volume, the concentration-volume math (0.1 mL total) is the first test.

How does co-administration language in Claim 15 affect enforcement scenarios?

Claim 15 is dependent on Claim 1 and narrows to regimens where intranasal naloxone is co-administered with IM and/or IV naloxone. This supports claims against:

responders’ stepwise treatment protocols,
label directions allowing subsequent IM/IV rescue.

However, in typical regulatory labeling, IM/IV rescue may be standard. If a product’s use instructions foresee escalation, the co-administration element can become a fact pattern advantage for enforcement.

Key claim summary in “infringement checklist” form

Claim element	What to match in an accused product/regimen
Treat opioid overdosing	Medical use context (labeling/indication/practice)
Route	Intranasal administration
Volume	Total 100 µL
Active	Naloxone or pharmaceutically acceptable salt
Concentration window	13–66 mg/mL naloxone HCl-equivalent
Application fluid	“Dissolved in” application fluid; Claim 11 narrows to water/aqueous saline
Dosage units	Single unit (one nostril) or two units (two nostrils) with half dose each for Claim 17
Delivery format	Claim 13 captures nasal spray / mucoadhesive / mucosal atomizer
Active-only	Claim 14 requires naloxone as only active
Co-admin	Claim 15 includes optional IM/IV naloxone co-administration

Key Takeaways

US 12,458,591 is a dose-geometry-centered method-of-use patent for intranasal naloxone in 100 µL total volume with 13–66 mg/mL naloxone HCl-equivalent.
Dependent claims create strong coverage for specific concentration bands and exact concentrations (notably 13, 15, 20, 40, 66 mg/mL, and ranges 13–16, 18–20, 20–50, 20–60).
Coverage includes multiple delivery technologies (nasal spray, mucoadhesive, mucosal atomizer) and multiple nostril dosing structures (one or two units).
Design-around efforts must target at least one of: total volume (100 µL), concentration window (mg/mL HCl-equivalent), active-only composition, application fluid type, or the intranasal treatment practice context.
Co-administration with IM/IV naloxone is expressly contemplated, supporting enforcement against stepwise emergency protocols.

FAQs

Can a product with a different naloxone salt form avoid infringement if the HCl-equivalent concentration still falls in the claimed range?
The claim uses “equivalent” concentration to naloxone HCl per ml, so salt form changes do not automatically avoid the concentration limitation.
Does a competitor need to match the same dosing-unit geometry (one nostril vs two nostrils) to infringe Claim 1?
No for Claim 1; the one- vs two-nostril language is in dependent claims. Claim 1 only requires intranasal administration at 100 µL total and the concentration window.
If a product uses a nasal atomizer, does that automatically satisfy the device limitation?
It helps with dependent Claim 13 if the device fits “mucosal atomizer device.” Claim 1 itself does not require a particular atomization type.
How would changing from water to a different solvent affect infringement?
It directly attacks dependent Claim 11. For Claim 1, it depends on whether the accused product still meets “application fluid” requirements and the concentration limitation as construed.
Is the patent more vulnerable to noninfringement arguments based on volume or concentration?
Concentration is tightly tied to exact mg/mL subranges and the fixed 100 µL volume. For noninfringement, altering either is typically more decisive than changing excipients that do not move concentration-volume math.

References

U.S. Patent No. 12,458,591.

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Patented / Exclusive Use	Submissiondate
Harm Reduction Therp	RIVIVE	naloxone hydrochloride	SPRAY, METERED;NASAL	217722-001	Jul 28, 2023		OTC	Yes	Yes	⤷ Start Trial	⤷ Start Trial				USE OF INTRANASAL NALOXONE FOR THE TREATMENT OF OPIOID OVERDOSE	⤷ 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

Country	Patent Number	Estimated Expiration	Supplementary Protection Certificate	SPC Country	SPC Expiration
Argentina	086391	⤷ Start Trial
Austria	16553	⤷ Start Trial
Australia	2012257785	⤷ Start Trial
>Country	>Patent Number	>Estimated Expiration	>Supplementary Protection Certificate	>SPC Country	>SPC Expiration

Details for Patent: 12,458,591

Which drugs does patent 12,458,591 protect, and when does it expire?

Summary for Patent: 12,458,591