Details for Patent: 11,890,273

Which drugs does patent 11,890,273 protect, and when does it expire?

Patent 11,890,273 protects ARBLI and is included in one NDA.

This patent has one patent family member in one country.

Summary for Patent: 11,890,273

Title:	Losartan liquid formulations and methods of use
Abstract:	The present disclosure relates to stable, liquid pharmaceutical compositions of losartan or pharmaceutically acceptable salts thereof for oral administration. The present disclosure further provides powder compositions for reconstitution to provide a liquid formulation. In further aspects, the present disclosure relates to processes for preparation of such pharmaceutical compositions, and methods of treating a subject in need of losartan by administration of a formulation described herein.
Inventor(s):	Bhavya Teja KOLLA, Rahul Surana, Suketu Sanghvi, Jigar BHATT
Assignee:	Meds Merger Sub Ii LLC , Scienture LLC
Application Number:	US18/052,116
Patent Claim Types: see list of patent claims	Use; Composition; Compound;

United States Patent 11,890,273 (Losartan Oral Suspension) Claim Scope and Patent Landscape Analysis

United States Patent 11,890,273 is directed to an oral losartan suspension defined by a tightly parameterized formulation matrix (concentration ranges for losartan and specific excipient functional classes), a required pH ~7, and measurable stability performance tied to degradation markers (losartan impurity D and impurity E) and losartan retention after storage under defined humidity/temperature conditions. The claims span (i) composition claims with storage-stability thresholds, (ii) dependent narrowing selections for suspending agents, preservatives, pH buffers, solubilizers, and antifoaming agents, and (iii) a broad method-of-treatment use claim framed as dosing for conditions responsive to angiotensin II receptor inhibition.

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What does US Drug Patent 11,890,273 claim for losartan oral suspensions?

Core claim type: composition of matter (oral suspension) with performance characteristics.

Independent claim 1 (formulation + stability performance):
An oral pharmaceutical composition that is a suspension with pH ~7, containing:

1. Losartan (free base or pharmaceutically acceptable salt) at 1–10 mg/mL
2. Suspending agent at 0.5–1.5 mg/mL chosen from:
   • hydroxyethylcellulose
   • methylcellulose
   • hydroxymethylcellulose
   • hydroxypropylmethylcellulose
   • microcrystalline cellulose
   • sodium carboxymethylcellulose
   • xanthan gum
   • acacia
   • an alginate
   • guar gum
3. pH modifying agent
4. Crystallization inhibitor at 5–15 mg/mL chosen from:
   • polyvinylpyrrolidone (PVP)
   • hydroxypropyl methylcellulose (HPMC)
   • polyvinyl acetate
   • cyclodextrin
   • hydroxypropyl-β-cyclodextrin
5. Preservative at 0.1–3 mg/mL chosen from:
   • methyl paraben, ethyl paraben, propyl paraben, butyl paraben
   • benzoic acid, sodium benzoate
   • benzalkonium chloride
6. Antifoaming agent at 1–10 mg/mL
7. Solubilizer at 20–60 mg/mL chosen from:
   • cremophor
   • vitamin E
   • PEG 400
   • propylene glycol
   • co-solvent
8. Required stability outcomes after “storage at room temperature and 60% RH,” specifically:
   • after 12 months: <0.5 wt/wt% losartan impurity D + impurity E (relative to losartan in the suspension)
   • after 12 months: ≥95% of initial losartan remains

Independent claim 4 (same formulation architecture, but broader buffers and distinct stability timelines/cutoffs):
Claim 4 is similar in ingredient classes, but adds an alternative stability framework: stability can be met by one or more of these scenarios:

• Stable for 6 months at 40°C/75% RH:
  • after 6 months: <2 wt/wt% impurity D + E
  • after 6 months: ≥97% losartan retention
• Or stable for 12 months at 30°C/65% RH:
  • after 12 months: <1 wt/wt% impurity D + E
  • after 12 months: ≥98% retention
• Or stable for 12 months at 2–8°C:
  • after 12 months: <0.5 wt/wt% impurity D + E
  • after 12 months: ≥99% retention

Independent claim 5–7 narrow further (single-point concentration and pH):

• Claim 5: losartan at ~10 mg/mL
• Claim 6: salt is losartan potassium
• Claim 7: suspension pH of 7

Independent claim 20 (composition without crystallization inhibitor requirement):

• losartan 1–10 mg/mL
• suspending agent 0.5–1.5 mg/mL from the same class
• pH modifying agent
• preservative 0.1–3 mg/mL
• suspension pH ~7
• same room temperature/60% RH, 12-month performance metrics as claim 1:
  • impurity D + E <0.5 wt/wt%
  • losartan retention ≥95%

Interpretive impact: Claim 20 is narrower than claim 1 in terms of excipient classes included, but still binds the formulation to a performance standard and core suspension design (losartan concentration, suspending agent class, pH, preservative presence, and the impurity/retention targets).

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How broad are the claim ranges and which excipient lists control infringement risk?

Losartan loading

• 1–10 mg/mL in the main independent claims.
• Practical effect: products at <1 mg/mL or >10 mg/mL fall outside literal scope, unless doctrine-of-equivalents arguments exist in a specific jurisdiction.

Suspensions: suspending agent “class list”

The claims use a defined list for suspending agents. Literal coverage turns on whether the accused formulation uses one of the listed materials (or combinations) at 0.5–1.5 mg/mL.

• Included examples likely to be used in commercial suspensions:
  • methylcellulose / HPMC
  • xanthan gum
  • sodium carboxymethylcellulose
  • microcrystalline cellulose
• Excluded-by-list examples (not listed): would not be captured literally unless substituted material is argued equivalent and the range and functionality map.

Crystallization inhibitor “class list”

This is a major scope driver in claim 1 and claim 4:

• PVP, HPMC (hydroxypropyl methylcellulose), polyvinyl acetate, cyclodextrin, hydroxypropyl-β-cyclodextrin
• at 5–15 mg/mL

If an accused product omits this functional excipient class or uses a different inhibitor family (not in the list), literal infringement for claim 1/4 narrows sharply.

Solubilizer “class list”

• at 20–60 mg/mL
• chosen from: cremophor, vitamin E, PEG 400, propylene glycol, co-solvent

PEG 400 and propylene glycol show up repeatedly in dependent claims, signaling that the patent is designed around common solubilizer systems but locks concentration ranges and list membership.

Preservatives

• 0.1–3 mg/mL
• list includes paraben family, benzoates, and benzalkonium chloride.
• Dependent claims specify likely species:
  • claim 10: methyl paraben and/or propyl paraben
  • claim 11: also defines pH buffers (phosphate monobasic/dibasic) as a pH modifying agent species

Antifoaming agent

• 1–10 mg/mL
• claim 16: simethicone emulsion
• claim 17 links specific system components including simethicone emulsion and sucralose (<1 wt%)

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Which stability requirements materially narrow the claim scope?

The claims use measurable impurity and retention thresholds, which can be decisive in both infringement and validity defenses.

Claim 1 stability trigger

• “storage at room temperature and 60% RH”
• 12 months
• impurity D + impurity E: <0.5 wt/wt%
• losartan retained: ≥95%

Claim 4 stability triggers (tiered alternative performance)

Accused products need to meet at least one of the listed stability regimes:

• 40°C/75% RH for 6 months:
  • impurities: <2 wt/wt%
  • retention: ≥97%
• 30°C/65% RH for 12 months:
  • impurities: <1 wt/wt%
  • retention: ≥98%
• 2–8°C for 12 months:
  • impurities: <0.5 wt/wt%
  • retention: ≥99%

Why this matters

Stability outcomes can be:

• product-specific (manufacturing process, particle size, vessel headspace, filtration/bio-burden strategy, lyophilized vs suspended raw materials, and oxygen exposure)
• assay-specific (how impurity D and impurity E are measured and normalized)

The claims are drafted to tie the suspension to these quantitative outcomes, which increases the chance that a non-identical formulation might still avoid literal infringement if it fails the impurity/retention thresholds, even when ingredient classes overlap.

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How do the dependent claims narrow scope (and where do they create additional “patent hooks”)?

Suspending agent narrowed species

• Claim 3: suspending agent selected from methylcellulose, hydroxypropylmethylcellulose, and xanthan gum (or combinations)
• Claim 15: suspending agent comprises xanthan gum

pH modifying agent narrowed species

• Claim 11: sodium phosphate monobasic and/or sodium phosphate dibasic

Preservative narrowed species

• Claim 10: methyl paraben and/or propyl paraben

Solubilizer, buffers, and flavors

• Claim 13:
  • PEG 400 and/or propylene glycol: 20–30 mg/mL
  • phosphate monobasic: 0.3–1.2 mg/mL
  • phosphate dibasic: 0.5–1.5 mg/mL
  • mint flavor: less than 10 wt/wt%

Crystallization inhibitor narrowed species

• Claim 14: PVP and/or hydroxypropyl methylcellulose

Antifoaming agent narrowed species

• Claim 16: simethicone emulsion

Multi-component “signature” dependent formulation

• Claim 17:
  • PVP: 10–20 mg/mL
  • xanthan gum: 1–2.5 mg/mL
  • simethicone emulsion: 5–10 mg/mL
  • sucralose: <1 wt/wt%

This claim acts as a practical infringement target if any commercial candidate mirrors these ingredients at those ranges.

Method-of-use claim

• Claim 18: administration to a mammalian subject for treatment of a condition responsive to angiotensin II receptor inhibition; “effective amount of losartan”
• Claim 19: mammalian subject is a human

This is broad in therapeutic language, but still tied to the composition in claim 18.

Additional excipient hook

• Claim 2: allows additional excipients from listed categories (emulsifying agent, antioxidant, chelating agent, surfactant/wetting agent, sweetener, stabilizer, flavoring agent, colorant)
• Claim 8: limits the excipient list to select categories (emulsifying agent, antioxidant, chelating agent, surfactant/wetting agent, sweetener, stabilizer, flavoring agent)

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How strong is the patent estate for this concept (what parts are most defensible)?

Within the four independent claims provided, the defensible “strength” typically clusters around:

1. Combination specificity
   The claims are not just “losartan suspension.” They require the combination of:

   • specific concentration ranges
   • specific excipient class lists
   • pH ~7
   • explicit stability outcomes against impurity D/E

2. Quantitative performance
   In many formulation disputes, the hardest-to-circumvent element is a quantitative stability threshold if it can be correlated to the formulation.

3. Alternative stability regimes in claim 4
   Claim 4 allows multiple routes to coverage based on temperature/humidity, making it harder to design around by targeting only one shelf-condition profile.

4. Independent claim 20 (reduced excipient set)
   Claim 20 removes the crystallization inhibitor requirement and some other classes from the ingredient set, but still requires the impurity/retention performance and baseline suspension/pH/preservative/suspending system architecture. That widens practical coverage against formulations that may use different excipient sets while still achieving the specified impurity/retention metrics.

5. Species-dependent dependent claims
   Dependent claims map onto commonly used formulation ingredients (PVP, HPMC, xanthan gum, PEG 400, propylene glycol, simethicone, phosphate buffers, parabens). Those dependencies can narrow to a “cleaner” invalidation or infringement analysis if an accused product matches a specific species list.

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What generic entry risks exist for losartan oral suspension tied to this patent?

Literal design-around paths

A competitor can reduce literal risk by ensuring at least one of the following is not met:

• losartan concentration outside 1–10 mg/mL (or ~10 mg/mL for the narrower dependent chain)
• suspending agent not in the listed set or not in 0.5–1.5 mg/mL
• pH not at ~7
• preservative not in listed set or not in 0.1–3 mg/mL
• missing required crystallization inhibitor list member in claim 1/4 (PVP, hydroxypropyl methylcellulose, polyvinyl acetate, cyclodextrin, hydroxypropyl-β-cyclodextrin) at 5–15 mg/mL
• solubilizer not in listed set or not in 20–60 mg/mL
• antifoaming not in listed concentration range or not the specified class for the dependent species
• failure to meet the stability thresholds for impurity D/E and retention under the specified storage conditions

Practical risk area

If a generic seeks to replicate a marketed suspension using standard excipients (PVP/HPMC, PEG/propylene glycol, parabens, phosphate buffers, simethicone, xanthan gum), it may drift toward the claim’s “signature” ranges and stability outcomes. The stability thresholds create a second barrier, but they can be met with formulation optimization.

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Regulatory and Orange Book status for US 11,890,273: what does it mean operationally?

You provided the claim text and patent number, but not the FDA NDA/BLA, reference product, NDA number, or Orange Book listing details. Without that linked dataset (patent-to-product mapping), the Orange Book status and any Paragraph IV challenge patterns cannot be stated from the provided information alone.

Operationally for a generic/sponsor team, the key action is matching:

• the dosage form (oral suspension)
• the route (oral)
• the strength (losartan mg/mL)
• the specific listed formulation parameters that map to Orange Book “claim coverage” scope (if the listing is tied to this patent)

This patent is structured to be listable as a formulation patent with explicit performance claims, which can be used to block or settle ANDA litigation where the proposed generic’s stability profile is scrutinized.

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Key Takeaways

• US 11,890,273 claims a losartan oral suspension with pH ~7, defined excipient concentration ranges, and quantitative stability requirements targeting losartan impurity D and impurity E.
• The strongest literal hooks are:
  • the crystallization inhibitor range (claim 1/4) at 5–15 mg/mL from a fixed list
  • the solubilizer range (claim 1/4) at 20–60 mg/mL from a fixed list
  • the stability thresholds after defined temperature/humidity regimes
• Claim 20 widens coverage by dropping crystallization inhibitor and some other classes while retaining key performance thresholds (impurity D/E and losartan retention).
• Generic design-around is most feasible by pushing at least one boundary off-target (ingredient range, excipient list membership, pH) or failing to meet the impurity D/E and retention criteria under the claimed storage conditions.

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FAQs

1. What excipient categories are mandatory in claim 1 versus claim 20?
   Claim 1 requires suspending agent, pH modifying agent, crystallization inhibitor, preservative, antifoaming agent, and solubilizer. Claim 20 omits the crystallization inhibitor and antifoaming/solubilizer lists but retains suspension, pH ~7, preservative, and suspending agent plus stability outcomes.

2. Does the patent cover losartan salts specifically or only free base?
   The claims cover losartan or a pharmaceutically acceptable salt, with a dependent claim specifically covering losartan potassium.

3. How can a competitor reduce impurity D/E degradation risk without copying the exact excipient list?
   The patent’s claim language ties stability to impurity D/E thresholds and retention. Avoidance can be attempted by changing excipient identity/ranges and demonstrating stability outcomes below/above the claimed thresholds under the cited storage conditions.

4. Are the stability requirements tied to a single test condition?
   No. Claim 1 uses room temperature/60% RH over 12 months. Claim 4 provides alternative regimes at 40°C/75% RH, 30°C/65% RH, or 2–8°C.

5. Is there a method-of-use claim that could survive if a formulation changes?
   Claim 18/19 is framed as dosing of the claimed composition for angiotensin II receptor inhibition responsive conditions, so if the formulation no longer falls within the composition scope, method-of-use coverage is less likely to apply.

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References

No external sources were cited because only the claim text and patent number were provided, and no FDA/Orange Book listing or prosecution history materials were included in the input.

Drugs Protected by US Patent 11,890,273

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Patented / Exclusive Use	Submissiondate
Scienture	ARBLI	losartan potassium	SUSPENSION;ORAL	218772-001	Mar 13, 2025		RX	Yes	Yes	11,890,273		Y

International Family Members for US Patent 11,890,273

Country	Patent Number	Estimated Expiration	Supplementary Protection Certificate	SPC Country	SPC Expiration
World Intellectual Property Organization (WIPO)	2022076746