US Patent 11,654,106: Atorvastatin Oral Suspension Claims, Patent Scope, and Generic Risk

US Patent 11,654,106 protects a narrowly defined aqueous atorvastatin suspension. The independent composition claim requires a specific excipient system, atorvastatin particle-size distribution, preservative, sweetener, flavor, and water vehicle. The patent also covers cholesterol-lowering treatment using the claimed suspension and dependent claims directed to stability, pH, and pharmacokinetic comparability.

The central infringement risk is concentrated in the formulation architecture: approximately 0.4% w/w atorvastatin, approximately 2% w/w combined suspending agents, with approximately 0.7% sodium carboxymethyl cellulose and approximately 1.3% magnesium aluminum silicate, plus a d90 particle size between 1 and 15 micrometers.

What does US Patent 11,654,106 protect?

Claim 1 protects an aqueous oral suspension containing all of the following:

Claim element	Required limitation
Atorvastatin	About 0.4% w/w
Total suspending agent	About 2% w/w
Sodium carboxymethyl cellulose	About 0.7% w/w
Magnesium aluminum silicate	About 1.3% w/w
Preservative	0.01% to 0.5% w/w
Sweetener	About 0.1% to 2% w/w
Flavoring agent	0.01% to 2.0% w/w
Vehicle	Water
Particle size	Atorvastatin d90 of 1 to 15 micrometers

The claim uses the transitional phrase “consisting of.” That language generally closes the claimed composition to additional, materially relevant ingredients, subject to established patent-law treatment of incidental components and claim construction. A competing formulation containing the same listed components could face literal infringement risk even if it includes other minor ingredients, depending on whether those ingredients are viewed as excluded by the closed formulation language.

The claim does not require a particular preservative, sweetener, flavor, or pH. Those variables are specified through broader dependent claims or remain open within the ranges in claim 1.

How should the “about” ranges in claim 1 be interpreted?

The principal uncertainty in claim 1 is the meaning of “about.” The claim does not define a numerical tolerance for:

0.4% w/w atorvastatin;
2% w/w total suspending agent;
0.7% w/w sodium carboxymethyl cellulose;
1.3% w/w magnesium aluminum silicate;
the sweetener range; or
the d90 particle-size range.

A court would ordinarily examine the specification, prosecution history, technical measurement methods, and industry practice to determine the permissible deviation. A formulation at 0.4% atorvastatin and 2.0% total suspending agent is the clearest literal example. A formulation materially outside those values may still present risk if the deviation is treated as insubstantial or equivalent.

The particle-size limitation is likely to receive particular scrutiny because d90 can vary with:

laser-diffraction instrument settings;
wet or dry dispersion;
sample preparation;
agglomeration;
whether the measurement is performed on atorvastatin before or after formulation; and
whether the active is measured as atorvastatin base or atorvastatin calcium.

A generic developer should treat the analytical method as part of the freedom-to-operate analysis.

What formulations are protected by the dependent claims?

Particle-size claims

Claim 2 narrows claim 1 to an atorvastatin d90 of 1 to 10 micrometers. It creates a more concentrated protection zone around finely milled or otherwise size-controlled atorvastatin.

Claims 8 and 9 narrow the composition further to atorvastatin having a d90 of approximately 6 micrometers. They also require pharmacokinetic comparability with a 40 mg atorvastatin tablet:

Claim 8 covers a T/R ratio for ln-transformed Cmax of 90% to 110%.
Claim 9 covers a T/R ratio for ln-transformed AUC0-t of 90% to 110%.

These are not ordinary composition-only limitations. They require a formulation that achieves a specified human pharmacokinetic relationship. The claims therefore combine a physical attribute, particle size, with a clinical or bioanalytical outcome.

Preservative claims

Claim 3 lists a broad group of preservatives, including:

alcohol;
benzyl alcohol;
chlorobutol;
chlorocresol;
alkyl esters of parabens;
phenol;
phenyl ethanol;
sodium benzoate;
propylene glycol; and
chloroform.

Claim 4 narrows the formulation to an alkyl ester of paraben. A formulation using methylparaben or propylparaben could fall within this limitation if the remaining claim elements are met.

pH claims

Claims 5 and 6 cover pH ranges of 5 to 10 and 6 to 9, respectively. Claim 6 is narrower and creates a practical infringement concern for many oral suspensions designed for palatability, chemical stability, or preservative performance.

Stability claim

Claim 7 requires total atorvastatin-related impurities of approximately 0.4% w/w after three months at approximately 25°C and 40% relative humidity.

This limitation is technically significant because it requires a defined storage condition and impurity outcome. It may be difficult to assess from the public product label alone. Enforcement would likely require batch records, stability protocols, analytical methods, and test results. The claim also raises measurement questions concerning:

the definition of “atorvastatin-related impurities”;
the analytical assay;
the treatment of degradation products;
the starting point for the three-month period; and
the meaning of “about 0.4%.”

How broad are the method-of-use claims?

Claim 10 covers administering a therapeutically effective amount of the claimed aqueous suspension to a human who needs cholesterol reduction. Claim 11 narrows the method to a dose containing 40 mg of atorvastatin.

The method claims do not cover atorvastatin generally. They require use of the composition of claim 1. A party selling a formulation that falls outside claim 1 may avoid these method claims even if the product is used to lower cholesterol.

The 40 mg limitation in claim 11 is commercially relevant because 40 mg is a common high-intensity atorvastatin dose. A 40 mg dose could be delivered through a higher concentration or a larger volume, but the formulation still must satisfy the composition limitations incorporated from claim 1.

What is the likely commercial concentration of the claimed suspension?

At 0.4% w/w atorvastatin, the formulation contains approximately 4 mg of atorvastatin per gram of suspension. Assuming a density close to 1 g/mL, a 40 mg dose would require approximately 10 mL.

That calculation is an approximation because the claims use weight percentages, not milligrams per milliliter. The actual administered volume depends on formulation density and the labeled concentration.

The claimed concentration differs from the 1 mg/mL concentration associated with certain commercial atorvastatin oral suspensions. A product at 1 mg/mL would contain approximately 0.1% w/v active ingredient, although direct comparison with the patent’s 0.4% w/w limitation requires accounting for density and whether the active is measured as atorvastatin or atorvastatin calcium equivalent.

What is the patent’s strongest infringement position?

The strongest position is a formulation that matches the following profile:

Approximately 0.4% w/w atorvastatin.
Approximately 2% w/w combined sodium carboxymethyl cellulose and magnesium aluminum silicate.
Approximately 0.7% w/w sodium carboxymethyl cellulose.
Approximately 1.3% w/w magnesium aluminum silicate.
A listed preservative.
Atorvastatin d90 near 6 micrometers.
pH between 6 and 9.
Total related impurities near 0.4% after the specified storage period.
Human PK results within the stated Cmax or AUC ratio.

Claims 1, 2, 5, 6, 8, and 9 create overlapping protection around that formulation. A product may infringe claim 1 even if it does not satisfy the narrower pH, stability, or PK limitations.

What design-around options exist?

Potential design-around strategies include changing one or more required elements:

Design-around variable	Potential effect
Reduce or increase atorvastatin concentration materially	May avoid the 0.4% limitation
Replace sodium carboxymethyl cellulose	May avoid the required suspending-agent combination
Replace magnesium aluminum silicate	May avoid claim 1
Alter the ratio of the two suspending agents	May avoid the “about 0.7%” and “about 1.3%” limitations
Use a different dosage form	A tablet, capsule, solution, or powder may fall outside the composition claim
Use a nonaqueous vehicle	May avoid the water-vehicle limitation
Use substantially larger atorvastatin particles	May avoid the d90 limitation
Use a concentration materially different from 0.4%	May avoid the central active-ingredient limitation
Change the preservative system	May avoid claims 3 and 4, but not necessarily claim 1
Use a different suspension technology	May reduce overlap with the specific excipient architecture

Changing only the preservative may not be sufficient because claim 1 requires a preservative but does not limit it to the specific list in claim 3. Similarly, changing the pH does not avoid claim 1 because pH is absent from that independent claim.

When does US Patent 11,654,106 lose exclusivity?

The patent’s exact expiration date cannot be established from the claim text alone. US utility patents generally expire 20 years from the earliest effective nonprovisional or international filing date, subject to patent-term adjustment, patent-term extension, terminal disclaimers, and continuity issues under 35 U.S.C. §§ 154 and 156.

The grant number indicates that the patent issued in 2023, but the grant date does not determine the expiration date. A reliable term analysis must use the USPTO patent record and continuity data. A continuation can have a 20-year term measured from an earlier parent application, while patent-term adjustment can extend the term beyond the ordinary calculation. The patent record, not the label or grant date, controls the calculation [1][2].

What is the Orange Book status of US Patent 11,654,106?

The Orange Book status cannot be inferred from the patent claims. FDA listing depends on whether the patent owner or approved-product sponsor submitted the patent for an approved drug product and whether FDA accepted the listing under the applicable statutory categories.

For an atorvastatin oral suspension, relevant Orange Book categories would generally concern:

drug substance;
drug product or formulation; and
method of use.

A formulation patent may be listed if it claims the approved drug product or an approved formulation under FDA’s listing rules. A method claim may be listed if it covers an approved use and is submitted in the required form. The existence of a granted patent does not itself establish Orange Book listing [3].

The practical consequence is that a Paragraph IV notice may create Hatch-Waxman litigation risk only if the patent is listed against the relevant reference drug and the ANDA applicant certifies against it. If the patent is not listed, the applicant may not face the same statutory 30-month stay mechanism based on that patent.

Are Paragraph IV challenges likely?

A Paragraph IV challenge would have several possible targets:

Anticipation

A challenger could argue that a single prior-art reference discloses all claim 1 elements, including:

the approximate active concentration;
both specified suspending agents at the claimed levels;
preservative, sweetener, flavor, and water;
the particle-size limitation; and
the closed composition structure.

The combination of excipient concentrations and particle size may make anticipation more difficult than a challenge based on atorvastatin suspension technology generally.

Obviousness

Obviousness is likely to be the principal validity issue. A challenger could combine prior art relating to:

atorvastatin’s poor aqueous solubility;
oral suspension vehicles;
sodium carboxymethyl cellulose;
magnesium aluminum silicate;
particle-size reduction;
preservative systems; and
stability improvement.

The patent owner would likely rely on formulation optimization, stability, sedimentation, redispersibility, palatability, and PK results. Claims 8 and 9 may be more difficult to attack with routine formulation references because they include human pharmacokinetic outcomes.

Indefiniteness and enablement

Potential issues include:

the scope of “about”;
the meaning of “atorvastatin-related impurities”;
the analytical method for d90;
the meaning of “about 6 μm”;
the treatment of atorvastatin versus atorvastatin calcium;
the definition of T/R ratio; and
whether the disclosure supports the full preservative and excipient breadth.

The strength of these defenses depends on the specification and prosecution history, not the issued claims alone.

What litigation and settlement risks affect generic entry?

A listed patent that is challenged through a Paragraph IV certification can trigger patent litigation under 35 U.S.C. § 271(e)(2). The filing of an infringement action within the statutory period can result in a 30-month stay of FDA approval, subject to statutory exceptions and court action [4].

A settlement could include:

a licensed entry date;
a permitted formulation;
a covenant not to sue;
restrictions on manufacturing or suppliers;
an authorized-generic arrangement; or
a no-admission resolution.

No settlement terms should be presumed from the existence of the patent. Settlement analysis requires the relevant court docket, ANDA number, Orange Book listing, and agreement disclosures.

How does this patent compare with the broader atorvastatin patent landscape?

The original atorvastatin product, Lipitor, has long passed the principal composition and basic product exclusivity period. Generic atorvastatin tablets and capsules are widely available. The commercial protection at issue here is different: it concerns a liquid oral suspension with a particular excipient system and particle-size distribution.

Technology area	Relevance to US 11,654,106
Atorvastatin active ingredient	Background technology; generally weak as a standalone exclusivity position
Tablet composition	Usually outside the aqueous suspension claims
Oral liquid suspension	Directly relevant
Particle-size reduction	Directly relevant to claims 1, 2, 8, and 9
Suspending-agent system	Central to claim 1
Stability and impurity control	Relevant to claim 7
PK comparability	Relevant to claims 8 and 9
Cholesterol-lowering use	Relevant only when used with the claimed formulation
Biosimilar pathway	Not relevant
Small-molecule ANDA pathway	Potentially relevant

There is no biosimilar risk because atorvastatin is a chemically synthesized small molecule, not a biologic subject to the FDA biosimilar pathway. Competitive entry would proceed through an ANDA or, depending on the product and clinical differences, a 505(b)(2) application [5][6].

What manufacturing and technical barriers does the patent create?

The patent creates more than a simple excipient substitution problem. A competing manufacturer may need to control:

milling or particle-size classification;
d90 measurement;
uniform dispersion of a poorly water-soluble active;
suspension viscosity;
sedimentation rate;
redispersibility after storage;
preservative effectiveness;
impurity formation;
microbial quality;
taste masking; and
dose uniformity.

The use of magnesium aluminum silicate and sodium carboxymethyl cellulose at specified levels suggests that rheology and physical stability are central technical features. A formulation can avoid the patent while creating separate development problems involving sedimentation, syringeability, dose accuracy, or chemical degradation.

How strong is the patent estate based on these claims?

The patent appears strongest as a narrow formulation patent and weaker as a broad atorvastatin exclusivity patent.

Strengths

Claim 1 combines multiple quantitative formulation limitations.
The excipient combination is specific.
Particle size provides a measurable technical limitation.
Claims 8 and 9 add human PK outcomes.
Stability and pH claims create additional overlapping positions.
The claims target a liquid dosage form that is less commoditized than atorvastatin tablets.

Weaknesses

“About” may create claim-construction disputes.
The 0.4% concentration and excipient levels may be vulnerable to obviousness arguments based on formulation optimization.
PK ratios may be difficult to enforce without access to human study data.
The stability claim depends on analytical definitions and test conditions.
A competitor can potentially change the dosage form, concentration, excipient system, or particle size.

The estate is therefore commercially meaningful for a matching oral suspension but does not block generic atorvastatin products generally.

What generic launch scenarios exist?

Launch scenario	Risk profile
Exact or near-exact suspension matching the claimed composition	High infringement risk
Suspension using the same two suspending agents but different ratios	Fact-specific; claim 1 remains a concern
Suspension with a different thickener system	Lower literal infringement risk
1 mg/mL suspension with materially different composition	Potentially lower risk, subject to “about” construction
505(b)(2) product with a different formulation	Patent and regulatory risk depend on overlap and listed patents
Tablet or capsule ANDA	Generally outside these claims
Nonaqueous liquid formulation	Potentially outside claim 1
Suspension with larger particles	May avoid particle-size limitations but not necessarily all of claim 1

An ANDA applicant must separately evaluate whether the reference product is the same dosage form, whether a waiver or clinical study is required, and whether formulation differences affect bioequivalence. FDA’s product-specific guidance and ANDA requirements govern the regulatory pathway [5][7].

Key Takeaways

US Patent 11,654,106 is a formulation patent directed to an aqueous atorvastatin oral suspension.
Claim 1 requires approximately 0.4% w/w atorvastatin, a defined CMC/magnesium aluminum silicate system, preservative, sweetener, flavor, water, and a d90 particle size of 1 to 15 micrometers.
Claims 8 and 9 add a d90 of approximately 6 micrometers and human PK ratios for Cmax or AUC.
Claims 10 and 11 cover cholesterol reduction using the claimed suspension, including a 40 mg dose.
The patent does not broadly block atorvastatin tablets, capsules, or all atorvastatin liquids.
The principal generic risk is a formulation that reproduces the excipient ratios and particle-size profile.
Exact patent expiration, Orange Book listing, Paragraph IV exposure, litigation status, and settlement risk require the USPTO, FDA Orange Book, and court records for the relevant patent and reference product.
Biosimilar risk is not applicable because atorvastatin is a small-molecule drug.

FAQs About US Patent 11,654,106

Does a 1 mg/mL atorvastatin suspension infringe US Patent 11,654,106?

Not automatically. A 1 mg/mL product is materially different from a formulation containing approximately 0.4% w/w atorvastatin, but infringement depends on the complete formulation, density, particle size, excipients, and construction of “about.”

Can a manufacturer avoid the patent by changing only the preservative?

Usually not necessarily. Claim 1 requires a preservative but does not limit it to the preservatives listed in claim 3. Changing the preservative may avoid claims 3 and 4 while leaving claim 1 exposed.

Does atorvastatin calcium fall within claims referring to atorvastatin?

The answer depends on the patent specification, prosecution history, and how the claims define the active ingredient. The distinction between atorvastatin, atorvastatin calcium, and atorvastatin-equivalent dosing should be addressed in a claim-construction and formulation analysis.

Are claims 8 and 9 easy to design around?

Potentially. A formulation with a different particle size or without the claimed PK relationship may avoid those narrower claims. It could still fall within claim 1 if the composition and particle-size range remain within the broader limitations.

Can a generic tablet be blocked by this patent?

Generally, no. The claims are directed to an aqueous suspension and methods using that suspension. A tablet would ordinarily fall outside the claimed dosage form, although other patents could create separate barriers.

Sources

United States Patent and Trademark Office. (n.d.). Patent term adjustment and patent term extension provisions. https://www.uspto.gov
United States Patent and Trademark Office. (2023). United States Patent No. 11,654,106.
U.S. Food and Drug Administration. (n.d.). Approved drug products with therapeutic equivalence evaluations: Orange Book. https://www.fda.gov
Drug Price Competition and Patent Term Restoration Act, 21 U.S.C. § 355(j); 35 U.S.C. § 271(e)(2).
U.S. Food and Drug Administration. (n.d.). Abbreviated new drug application (ANDA) process. https://www.fda.gov
U.S. Food and Drug Administration. (n.d.). Biosimilar and interchangeable biologic products. https://www.fda.gov
U.S. Food and Drug Administration. (n.d.). Bioequivalence studies with pharmacokinetic endpoints for drugs submitted under an ANDA. https://www.fda.gov

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Patented / Exclusive Use	Submissiondate
Cmp Dev Llc	ATORVALIQ	atorvastatin calcium	SUSPENSION;ORAL	213260-001	Feb 1, 2023		RX	Yes	Yes	11,654,106	⤷ Start Trial	Y			AS AN ADJUNCT TO DIET TO REDUCE LOW-DENSITY LIPOPROTEIN CHOLESTEROL IN ADULTS AND PEDIATRIC PATIENTS AGED 10 YEARS AND OLDER WITH HETEROZYGOUS FAMILIAL HYPERCHOLESTEROLEMIA	⤷ Start Trial
Cmp Dev Llc	ATORVALIQ	atorvastatin calcium	SUSPENSION;ORAL	213260-001	Feb 1, 2023		RX	Yes	Yes	11,654,106	⤷ Start Trial	Y			AS AN ADJUNCT TO OTHER LOW-DENSITY LIPOPROTEIN CHOLESTEROL (LDL-C) LOWERING THERAPIES, OR ALONE IF SUCH TREATMENTS ARE UNAVAILABLE, TO REDUCE LDL-C IN ADULTS AND PEDIATRIC PATIENTS AGED 10 YEARS AND OLDER WITH HOMOZYGOUS FAMILIAL HYPERCHOLESTEROLEMIA	⤷ 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
European Patent Office	3468606	⤷ Start Trial
World Intellectual Property Organization (WIPO)	2017212409	⤷ Start Trial
>Country	>Patent Number	>Estimated Expiration	>Supplementary Protection Certificate	>SPC Country	>SPC Expiration

Details for Patent: 11,654,106

Which drugs does patent 11,654,106 protect, and when does it expire?

Summary for Patent: 11,654,106