Details for Patent: 11,576,894

Which drugs does patent 11,576,894 protect, and when does it expire?

Patent 11,576,894 protects INVOKAMET and is included in one NDA.

This patent has fifty-one patent family members in forty countries.

Summary for Patent: 11,576,894

Title:	Combination therapy for the treatment of diabetes
Abstract:	The present invention is directed to co-therapy and methods for the treatment and prevention of glucose-related disorders such as Type 2 diabetes mellitus and Syndrome X. The present invention is further directed to pharmaceutical compositions for the co-therapy and methods described herein.
Inventor(s):	Yin Liang, John Ryan, Abraham B. Woldu, Lisa Wu
Assignee:	Janssen Pharmaceutica NV
Application Number:	US15/413,480
Patent Litigation and PTAB cases:	See patent lawsuits and PTAB cases for patent 11,576,894
Patent Claim Types: see list of patent claims	Composition; Compound;

US Patent 11,576,894: Claim Scope, Validity Risks, and Patent-Landscape Analysis

US Patent No. 11,576,894 protects specific immediate-release pharmaceutical compositions combining metformin with an unidentified formula-I compound, using microcrystalline cellulose, a specified cellulose or povidone binder, and croscarmellose sodium. The strongest protection is concentrated in claims 3-12, which require metformin hydrochloride, the narrower formula I-X compound, defined dose combinations, and specified excipient ranges.

A complete drug-specific landscape cannot be established from the supplied text because the chemical structures for formula I and formula I-X are omitted. The claims identify a Markush chemical class, but they do not disclose the compound’s name, active ingredient, structure, assignee, priority application, or marketed product.

What does US Patent 11,576,894 protect?

The patent claims a pharmaceutical composition containing four principal elements:

1. Metformin or metformin hydrochloride.
2. A second compound within a defined formula-I or formula I-X chemical class.
3. Microcrystalline cellulose as the diluent.
4. A specified binder and croscarmellose sodium as the disintegrant.

Claim 12 adds a lubricant requirement.

The patent therefore does not broadly cover every metformin combination. Infringement generally would require the accused product to satisfy the claimed active-ingredient identity, dosage range, excipient identity, and percentage limitations.

Core claim limitations

Limitation	Claims 1-2	Claims 3-12
Metformin component	Metformin or pharmaceutically acceptable salt	Metformin hydrochloride
Metformin amount	About 500-2,000 mg	About 100-2,000 mg
Second active	Formula-I compound	Formula I-X compound
Second-active amount	About 10-300 mg	About 50-500 mg
Diluent	Microcrystalline cellulose, 5%-50%	Microcrystalline cellulose, 5%-50%
Binder	PVP, methylcellulose, HPC, or HPMC, 1%-10%	Same
Disintegrant	Croscarmellose sodium, 1%-10%	Same
Crystalline form	Not expressly required	Claim 5 requires crystalline hemihydrate
Lubricant	Not required	Claim 12 requires 0.1%-2%

The percentages appear to be weight percentages of the finished composition unless the patent specification defines a different basis. That definition is material to infringement analysis.

How broad is independent claim 1?

Claim 1 is compositionally broad but chemically limited.

It covers a tablet or other pharmaceutical composition containing:

• 500-2,000 mg of metformin or a pharmaceutically acceptable salt;
• 10-300 mg of the formula-I compound or its salt;
• 5%-50% microcrystalline cellulose;
• 1%-10% of at least one listed binder; and
• 1%-10% croscarmellose sodium.

The chemical limitation is imposed through Ring A, Ring B, R1a, R2a, R3a, R4a, Rya, and Y. Because the structural drawings are absent, the practical breadth of claim 1 cannot be measured. The relevant questions are whether formula I covers:

• a named commercial active ingredient;
• multiple stereochemical forms;
• free base and salt forms;
• polymorphs and hydrates;
• prodrugs;
• metabolites; or
• only a narrow disclosed compound series.

The phrase “about” introduces potential range-boundary disputes. Courts typically assess the intrinsic evidence, specification examples, formulation tolerances, and technical meaning of “about.” A product containing 480 mg or 2,050 mg of metformin could raise a doctrine-of-equivalents issue, but literal infringement would depend on the patent’s definitions and prosecution history.

What do claims 3-12 add?

Claims 3-12 narrow the composition to metformin hydrochloride and formula I-X.

Claim 3

Claim 3 requires:

• 100-2,000 mg metformin hydrochloride;
• 50-500 mg of formula I-X or its salt;
• 5%-50% microcrystalline cellulose;
• 1%-10% of the listed binder; and
• 1%-10% croscarmellose sodium.

This is likely the principal commercial formulation claim because it identifies the salt of metformin and narrows the second active to formula I-X.

Claim 4

Claim 4 specifies preferred dose points:

• Metformin hydrochloride: 250, 500, 750, 850, or 1,000 mg.
• Formula I-X compound: 50, 100, 150, or 300 mg.

The claim uses “about,” so the listed amounts may not be limited to exact tablet label strengths. The enforceable scope will depend on how the specification describes manufacturing tolerances and dosage strength.

Claims 5-11

Claim 5 requires the formula I-X compound to be a crystalline hemihydrate.

Claims 6-11 cover particular dose pairings:

Claim	Metformin hydrochloride	Formula I-X compound
6	About 500 mg	About 50 mg
7	About 1,000 mg	About 50 mg
8	About 500 mg	About 150 mg
9	About 1,000 mg	About 150 mg
10	About 850 mg	About 50 mg
11	About 850 mg	About 50 mg

Claims 10 and 11 are identical as supplied. That duplication may reflect an error in the claim text, a transcription issue, or an issued claim set containing redundant dependent claims. It does not, by itself, invalidate the patent. The issued patent and certificate of correction would control.

Claim 12

Claim 12 adds a lubricant at 0.1%-2% by weight. A commercial tablet using magnesium stearate, sodium stearyl fumarate, stearic acid, or another lubricant could fall within this claim if the patent does not restrict the lubricant identity elsewhere.

What formulations are protected by US 11,576,894?

The patent is directed to solid oral formulations, most plausibly tablets, containing a combination of metformin and the formula-I compound. The claims do not expressly require:

• immediate release;
• extended release;
• film coating;
• a bilayer tablet;
• a particular dissolution profile;
• a particular tablet hardness;
• a granulation process; or
• a specific lubricant.

Unless the specification or prosecution history imposes an unstated limitation, the claims may reach multiple solid dosage architectures if the claimed composition is present.

Excipient-based infringement risk

The excipient limitations create both protection and design-around opportunities.

A competing product may reduce risk by:

• replacing microcrystalline cellulose with lactose, mannitol, dibasic calcium phosphate, starch, or another diluent;
• using a binder outside the claimed list;
• replacing croscarmellose sodium with crospovidone or sodium starch glycolate;
• moving an excipient concentration outside the claimed range;
• using a separate bilayer formulation with materially different composition;
• omitting the claimed crystalline hemihydrate; or
• using a different salt or polymorph where the claims permit a distinction.

The doctrine of equivalents could limit some design-arounds, particularly where the substituted excipient performs substantially the same function in substantially the same way. Prosecution history estoppel and prior-art amendments would be critical.

How strong is the patent estate?

Based solely on the supplied claims, the patent appears to have a moderate formulation-focused scope and a potentially narrower practical enforcement position.

Strengths

• The claims combine active-ingredient identity with quantitative excipient limitations.
• Claims 3-12 target defined metformin strengths and second-active strengths.
• Claim 5 may provide separate protection for a crystalline hemihydrate.
• Claim 12 adds a further formulation limitation that may capture conventional tablet lubricants.
• A product matching the exact active ingredients, doses, and excipient ranges could face a strong literal-infringement case.

Weaknesses

• The claims are vulnerable to prior-art attacks based on known metformin combination tablets.
• Microcrystalline cellulose, croscarmellose sodium, and the listed binders are conventional pharmaceutical excipients.
• Dose combinations may be vulnerable where the individual actives, strengths, and fixed-dose combinations were already disclosed.
• The claims may be susceptible to obviousness arguments based on routine formulation optimization.
• The chemical scope cannot be assessed without the formula-I and formula I-X drawings.
• Claim 11 is duplicative of claim 10 as supplied.
• The specification must support the full breadth of the claimed active-ingredient and excipient ranges under written-description and enablement standards.

The patent’s value depends heavily on whether the formula-I compound is a commercially important active and whether the patent claims a product actually sold in the United States.

What prior art is most relevant?

The most important prior-art categories are:

Earlier combination products

Earlier patents and product disclosures covering metformin plus the same second active could challenge novelty or obviousness. The relevant evidence includes:

• fixed-dose combination patents;
• clinical-trial protocols;
• regulatory submissions;
• product labels;
• public formulation examples; and
• international patent families.

Separate active-ingredient disclosures

A challenger may combine:

• prior art for metformin hydrochloride tablets;
• prior art for the formula-I compound;
• prior art for the crystalline hemihydrate; and
• routine excipient teachings.

The obviousness case would be stronger if the prior art disclosed the same dosage strengths and conventional excipient system.

Crystalline-form prior art

Claim 5 depends on the formula I-X compound being a crystalline hemihydrate. Relevant references include:

• polymorph patents;
• hydrate and solvate filings;
• XRPD, DSC, TGA, and solid-state characterization publications;
• regulatory chemistry, manufacturing and controls documents; and
• earlier patent applications describing the same hemihydrate.

A crystalline-form claim requires careful comparison of solid-state identity. Chemical identity alone does not establish anticipation.

Does the patent cover a method of use?

The supplied claims are composition claims, not method-of-treatment claims. They do not expressly require:

• treatment of type 2 diabetes;
• glycemic control;
• administration to a patient;
• a dosing schedule;
• combination therapy as a clinical method; or
• a therapeutic outcome.

The patent therefore does not directly claim the therapeutic use of the combination in the language provided. Any method-of-use protection would need to appear in separate claims or related patents.

What is the Orange Book status?

A definitive Orange Book assessment cannot be made from the claim text because the active ingredient is unidentified and the patent’s FDA listing status is not provided.

For an FDA-approved small-molecule combination product, the relevant questions are:

Orange Book issue	Relevance
Listed drug	Whether a product containing the claimed active combination is approved
Patent listing	Whether US 11,576,894 is listed against that product
Patent use code	Whether the listing covers a method of use or only formulation
Expiration date	Whether the patent remains enforceable
Paragraph IV notice	Whether an ANDA applicant has challenged the listing
30-month stay	Whether litigation triggered an FDA approval stay
Pediatric exclusivity	Whether six-month exclusivity affects the listing period

Because the claims are formulation claims, the patent may be listed only if it claims an approved drug product or an approved method of using the product under FDA listing rules. A patent directed solely to an unapproved formulation or an unmarketed chemical entity would not automatically qualify for Orange Book listing.

When does US Patent 11,576,894 expire?

The patent number alone does not establish the enforceable expiration date. The relevant date requires the patent’s earliest effective nonprovisional priority date, patent term adjustment, patent term extension, terminal disclaimers, and any disclaimer or correction.

The standard US patent term is generally 20 years from the earliest effective nonprovisional filing date, subject to adjustments and extensions. The issue date, February 7, 2023, is not the expiration date.

A reliable expiration analysis must review:

• the front page priority data;
• the continuity statement;
• the USPTO Patent Center prosecution record;
• patent term adjustment;
• terminal disclaimer records;
• any patent term extension; and
• maintenance-fee status.

Are Paragraph IV challenges likely?

A Paragraph IV challenge would be commercially plausible if:

1. the patent is listed against an approved combination product;
2. the listed product has meaningful US sales;
3. the second active has an ANDA pathway;
4. the claimed formulation can be designed around; or
5. the challenger believes the claims are invalid or not infringed.

The strongest generic challenge theories would likely be:

• obviousness based on known metformin combination formulations;
• anticipation by an earlier fixed-dose combination disclosure;
• lack of written description for the full Markush genus;
• lack of enablement across the claimed chemical and formulation scope;
• indefiniteness concerning “about” and percentage bases; and
• noninfringement based on a different excipient, crystalline form, salt, or strength.

If the formula-I compound is a biologic or peptide, the relevant pathway would not be an ANDA Paragraph IV pathway. The supplied formulation claims appear more consistent with a small-molecule product, but the omitted structure prevents confirmation.

What generic launch scenarios exist?

Scenario 1: Exact formulation match

A generic matching the active ingredients, dose strengths, crystalline form, microcrystalline cellulose, listed binder, croscarmellose sodium, and claimed ranges would present the highest infringement risk.

Scenario 2: Excipient design-around

A generic may replace one or more claimed excipients. This could avoid literal infringement, although the doctrine of equivalents remains relevant.

Scenario 3: Separate tablets

A company could market the two actives as separate tablets rather than a single composition, subject to regulatory and labeling requirements. This may avoid composition claims requiring both actives in one pharmaceutical composition.

Scenario 4: Different solid form

Use of a non-hemihydrate form may avoid claim 5, but it would not avoid claims 3, 4, and 6-12 unless those claims are construed to require the hemihydrate.

Scenario 5: Different dose pairing

A product using a strength outside the preferred pairings may avoid claims 6-11 but could still fall within broader claims 1 or 3.

What litigation and settlement issues should be reviewed?

No litigation, Paragraph IV notice, settlement agreement, or district-court docket can be reliably attributed to US 11,576,894 from the supplied claim text alone.

The relevant litigation search should include:

• the patent number;
• the patent owner and exclusive licensees;
• the unidentified formula-I compound;
• the corresponding brand product;
• ANDA litigation under 21 U.S.C. § 355(j);
• declaratory-judgment actions;
• inter partes review petitions;
• post-grant review proceedings;
• Federal Circuit appeals; and
• FTC-filed or publicly reported patent settlements.

A settlement could include a deferred generic entry date, a license, a covenant not to sue, an authorized generic arrangement, or restrictions on formulation design. Without the patent owner and active ingredient, assigning any known settlement would risk error.

How does this patent compare with active-ingredient patents?

US 11,576,894 appears to be a combination-formulation patent rather than a basic composition-of-matter patent, based on the supplied claims.

Patent type	Typical scope	Relative commercial effect
Composition of matter	Chemical entity and broad salts	Usually strongest exclusionary right
Polymorph or hydrate	Specific solid form	Strong if product uses the claimed form
Combination patent	Two or more active ingredients	Depends on product architecture
Formulation patent	Excipients, release profile, dosage form	Often design-aroundable
Method-of-use patent	Treatment indication or dosing regimen	Depends on labeling and induced-infringement risk
Manufacturing patent	Process or intermediate	Stronger where process is difficult to detect or replace

The supplied patent may provide meaningful protection against an exact fixed-dose tablet but may not prevent all generic combinations, separate-tablet regimens, or formulations using different excipient systems.

Key Takeaways

• US 11,576,894 claims metformin combinations containing a formula-I compound and defined excipients.
• Claims 3-12 are narrower and focus on metformin hydrochloride plus formula I-X.
• Microcrystalline cellulose, a listed binder, and croscarmellose sodium are mandatory elements of the principal composition claims.
• Claim 5 separately targets a crystalline hemihydrate.
• Claims 6-11 identify specific metformin and formula I-X dose pairings, with claims 10 and 11 duplicative as supplied.
• The patent’s practical commercial importance depends on the identity of formula I-X and whether a corresponding FDA-approved product exists.
• The patent appears more vulnerable to formulation design-arounds and obviousness attacks than a composition-of-matter patent.
• Expiration, Orange Book listing, Paragraph IV activity, litigation, and settlement status cannot be determined reliably without the omitted chemical identity and patent-record data.

FAQs About US Patent 11,576,894

Is US 11,576,894 a metformin patent?

It is not a broad metformin patent. The supplied claims require metformin together with a second formula-I or formula I-X compound and specified excipients.

Does the patent cover metformin monotherapy?

No. The claims require a second active compound in addition to metformin.

Can a generic avoid the patent by removing croscarmellose sodium?

Potentially. Removing croscarmellose sodium may avoid literal infringement of claims 1, 3, and their dependents, but the complete formulation and any doctrine-of-equivalents analysis must be reviewed.

Does claim 5 protect every hydrate of formula I-X?

No. Claim 5 is limited to a crystalline hemihydrate. Other hydrates, solvates, polymorphs, or amorphous forms may fall outside that claim, although broader claims could still apply.

Does a separate metformin tablet and second-active tablet infringe?

A separately packaged or separately administered regimen may avoid a claim requiring a single pharmaceutical composition containing both actives. The result depends on product design, packaging, labeling, and the claim construction adopted by a court.

References

1. United States Patent and Trademark Office. (2023). U.S. Patent No. 11,576,894.
2. United States Code, 35 U.S.C. §§ 101, 102, 103, 112, 154.
3. United States Code, 21 U.S.C. § 355(j).
4. U.S. Food and Drug Administration. (2023). Approved drug products with therapeutic equivalence evaluations. FDA.

Drugs Protected by US Patent 11,576,894

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Patented / Exclusive Use	Submissiondate
Janssen Pharms	INVOKAMET	canagliflozin; metformin hydrochloride	TABLET;ORAL	204353-001	Aug 8, 2014		RX	Yes	No			Y
Janssen Pharms	INVOKAMET	canagliflozin; metformin hydrochloride	TABLET;ORAL	204353-002	Aug 8, 2014		RX	Yes	No			Y
Janssen Pharms	INVOKAMET	canagliflozin; metformin hydrochloride	TABLET;ORAL	204353-003	Aug 8, 2014		RX	Yes	No			Y
Janssen Pharms	INVOKAMET	canagliflozin; metformin hydrochloride	TABLET;ORAL	204353-004	Aug 8, 2014		RX	Yes	Yes			Y

International Family Members for US Patent 11,576,894

Country	Patent Number	Estimated Expiration	Supplementary Protection Certificate	SPC Country	SPC Expiration
Argentina	077464
Argentina	118805
Australia	2010270669
Australia	2015203067