United States Patent 9,439,901: Scope, Claims, Expiration, and Patent Landscape for Dapagliflozin-Sitagliptin Therapy

U.S. Patent No. 9,439,901 protects methods of treating obesity and Type 2 diabetes with a pharmaceutical composition containing dapagliflozin and sitagliptin. The patent is a narrow combination-use patent. It does not broadly claim dapagliflozin, sitagliptin, SGLT2 inhibition, DPP-4 inhibition, or all combinations of the two active ingredients.

The patent’s commercial significance is limited by three factors: it is directed to a specific composition and therapeutic use, no U.S.-approved fixed-dose dapagliflozin-sitagliptin product is marketed, and the patent does not independently block generic entry for Farxiga or Januvia.

What does U.S. Patent 9,439,901 claim?

The two issued claims cover human treatment methods using a composition that contains:

Dapagliflozin;
A pharmaceutically acceptable excipient, diluent, or carrier; and
Sitagliptin or a pharmaceutically acceptable salt.

The chemical name in the claims is dapagliflozin, the active ingredient in Farxiga and Forxiga. Sitagliptin is the active ingredient in Januvia and is also marketed in combination products such as Janumet with metformin.

Claim	Disease	Required active ingredients	Claim type
1	Obesity	Dapagliflozin and sitagliptin	Method of treatment
2	Type 2 diabetes	Dapagliflozin and sitagliptin	Method of treatment

The claims require administration to a human in need of treatment and use of a “therapeutically effective amount.” Neither claim specifies a dosage, dosage ratio, administration frequency, route, tablet design, release profile, or treatment duration.

What chemical entity does the patent cover?

The compound identified in each claim is dapagliflozin:

Chemical class: C-glucoside SGLT2 inhibitor
Brand: Farxiga in the United States; Forxiga in many other markets
Originator: Bristol-Myers Squibb and AstraZeneca
Current U.S. marketing holder: AstraZeneca
Primary mechanism: inhibition of sodium-glucose cotransporter 2, increasing urinary glucose excretion

The second active ingredient is sitagliptin:

Chemical class: DPP-4 inhibitor
Brand: Januvia
Originator: Merck
Primary mechanism: inhibition of DPP-4, increasing active incretin concentrations

The invention therefore combines two established glucose-lowering mechanisms rather than claiming a new molecular entity.

How broad are the claims of U.S. Patent 9,439,901?

The claims are chemically narrow but operationally broad within the defined combination.

The claims require both dapagliflozin and sitagliptin

A composition containing dapagliflozin alone does not fall within the literal scope of the claims. A composition containing sitagliptin alone also does not fall within the literal scope. The claimed combination must include both active ingredients.

The use of “comprising” is important. A composition containing dapagliflozin, sitagliptin, an excipient, and another active ingredient could still satisfy the claim, assuming the other claim elements are met. The claims therefore do not exclude triple or multi-drug combinations.

For example, a product containing dapagliflozin, sitagliptin, and metformin could potentially fall within the “comprising” language. By contrast, a dapagliflozin-saxagliptin product would not literally meet the sitagliptin limitation.

The claims do not require a fixed-dose combination

The claims refer to a pharmaceutical composition comprising both active ingredients. They do not expressly require:

A single tablet;
A single capsule;
A fixed dose;
A specified dapagliflozin-to-sitagliptin ratio;
Simultaneous release;
A particular formulation technology.

A single dosage form containing both compounds is the clearest infringement scenario. Separate administration may present a more complex issue because the claims are directed to administering a pharmaceutical composition comprising both ingredients. Whether a regimen using separate commercial products satisfies the claim would depend on the facts, the patent specification, prosecution history, and applicable infringement doctrine.

The claims are limited to human treatment

The claims require treatment of a human. Veterinary use is outside the literal claim language. The claims also require a human “in need” of treatment, which connects the administration to obesity or Type 2 diabetes.

The claims do not specify the degree of weight loss or glycemic control

The patent does not require a particular clinical outcome in the claim language. It requires administration of a therapeutically effective amount for the claimed condition. The efficacy question would generally concern whether the treatment was directed to the claimed disease and whether the administered amount was therapeutically effective.

When does U.S. Patent 9,439,901 expire?

The patent has a projected ordinary patent-term expiration in late 2030, calculated from the relevant nonprovisional filing date and subject to any patent-term adjustment or terminal disclaimer recorded by the USPTO.

Event	Date or status
Earliest priority period	2009
U.S. patent issuance	September 13, 2016
Patent number	9,439,901
Expected ordinary expiration	Approximately November 2030
Patent-term adjustment	Must be confirmed in USPTO Patent Center
Patent-term extension	No extension is generally associated with this method-of-treatment patent

The issue date does not control expiration. U.S. utility patents generally expire 20 years from the earliest effective nonprovisional filing date, subject to statutory adjustments. A terminal disclaimer, if present, could shorten the term.

The patent should therefore be analyzed separately from earlier dapagliflozin and sitagliptin patents. Earlier compound patents may have expired even though the combination-use patent remains within its own term.

What is the Orange Book status of U.S. Patent 9,439,901?

U.S. Patent 9,439,901 is not a conventional Orange Book barrier to generic Farxiga or Januvia entry.

The Orange Book lists patents submitted for approved drug products and associated approved uses. Patent 9,439,901 claims a dapagliflozin-sitagliptin composition and treatment methods. The United States has not approved a fixed-dose dapagliflozin-sitagliptin product corresponding to these claims.

The approved SGLT2/DPP-4 combination marketed in the United States is Qtern, which combines dapagliflozin with saxagliptin, not sitagliptin. Qtern therefore does not practice the specific sitagliptin limitation in Patent 9,439,901.

Product	Active ingredients	Relevant relationship to Patent 9,439,901
Farxiga	Dapagliflozin	Does not contain sitagliptin
Januvia	Sitagliptin	Does not contain dapagliflozin
Janumet	Sitagliptin and metformin	Does not contain dapagliflozin
Qtern	Dapagliflozin and saxagliptin	Contains the wrong DPP-4 inhibitor
Xigduo XR	Dapagliflozin and metformin	Does not contain sitagliptin

Because the patent is not the primary listed patent for an approved dapagliflozin-sitagliptin product, an ANDA applicant seeking approval of generic dapagliflozin or generic sitagliptin would not ordinarily need to submit a Paragraph IV certification specifically directed to Patent 9,439,901.

What Paragraph IV challenges affect dapagliflozin and sitagliptin?

Paragraph IV litigation has historically focused on the patents covering the individual active ingredients and approved products, not this unapproved combination.

Dapagliflozin

Dapagliflozin patent litigation has involved patents covering the compound, pharmaceutical compositions, treatment of diabetes, and related uses. The relevant patent family includes early Bristol-Myers Squibb and AstraZeneca patents associated with Farxiga and Forxiga.

A generic applicant challenging a listed Farxiga patent may file a Paragraph IV certification alleging that the patent is invalid, unenforceable, or not infringed. That proceeding concerns the listed Farxiga patent estate. It does not automatically resolve infringement of a separate method patent covering dapagliflozin with sitagliptin.

Sitagliptin

Sitagliptin’s primary composition-of-matter protection was associated with Merck’s Januvia franchise. Paragraph IV cases against sitagliptin products have similarly focused on compound, formulation, and use patents listed for Januvia, Janumet, or related products.

A generic sitagliptin applicant could enter the market with sitagliptin alone without practicing a claim requiring dapagliflozin. The same applies to a generic dapagliflozin product that does not contain sitagliptin.

What litigation or settlement risk is associated with Patent 9,439,901?

The patent presents a lower direct litigation risk for standalone generic products than for a commercial product that intentionally combines dapagliflozin and sitagliptin.

Litigation risk by product strategy

Product strategy	Direct risk under Patent 9,439,901
Dapagliflozin monotherapy	Low, because sitagliptin is absent
Sitagliptin monotherapy	Low, because dapagliflozin is absent
Dapagliflozin plus metformin	Low under the literal combination limitation
Dapagliflozin plus saxagliptin	Low under the literal sitagliptin limitation
Fixed-dose dapagliflozin-sitagliptin product	High, if marketed for obesity or Type 2 diabetes during the patent term
Co-packaged dapagliflozin and sitagliptin	Fact-dependent
Separate prescriptions for dapagliflozin and sitagliptin	Fact-dependent and dependent on how the claims are construed

No material U.S. settlement involving Patent 9,439,901 is commonly associated with the principal Farxiga or Januvia generic litigation record. The absence of a listed combination product reduces the probability of a Hatch-Waxman suit directed specifically to this patent.

A settlement could still matter if a company developed a fixed-dose dapagliflozin-sitagliptin product or sought approval for a labeled combination use. Such a settlement would likely address launch timing, field-of-use restrictions, or a covenant not to sue rather than generic entry for either standalone drug.

How strong is the patent estate for dapagliflozin plus sitagliptin?

The patent estate is stronger as a targeted blocking right than as a broad platform estate.

Strengths

The claims identify two specific active ingredients.
The claims cover both obesity and Type 2 diabetes.
The “comprising” language may capture combinations containing additional active ingredients.
The claims do not impose a narrow dose or formulation limitation.
The patent term extends beyond the expiration of many foundational compound patents.

Weaknesses

The patent does not cover either active ingredient individually.
It does not cover all SGLT2/DPP-4 combinations.
It does not cover dapagliflozin plus saxagliptin, empagliflozin plus sitagliptin, or other substituted combinations.
No approved U.S. product currently creates a direct commercial product-patent linkage.
The combination may face obviousness challenges based on the known use of dapagliflozin and sitagliptin as separate diabetes therapies.
The absence of specific dose, formulation, or clinical-result limitations can create both breadth and validity pressure.

The principal validity issue would likely be obviousness under 35 U.S.C. § 103. A challenger could argue that combining an SGLT2 inhibitor with a DPP-4 inhibitor was predictable in view of the existing diabetes treatment literature. The patent holder would rely on the claimed therapeutic combination, supporting data, unexpected effects, or other evidence in the prosecution record.

What formulations are protected?

The issued claims are not limited to a particular formulation technology. They require a pharmaceutical composition containing the specified ingredients and a pharmaceutically acceptable excipient, diluent, or carrier.

Potentially covered forms include:

Immediate-release tablets;
Capsules;
Multi-layer tablets;
Fixed-dose combination tablets;
Granules or powders;
Oral liquids;
Other pharmaceutical compositions containing both actives.

The claims do not expressly cover manufacturing processes, particle size, salt selection, polymorphs, enteric coatings, extended-release matrices, or dissolution specifications. Separate formulation or process patents would be needed to create those additional barriers.

Are biosimilars relevant to Patent 9,439,901?

No. Dapagliflozin and sitagliptin are chemically synthesized small molecules, not biologics. The principal competitive threats are generic drugs approved through the ANDA pathway, not biosimilars approved under the Public Health Service Act.

The relevant regulatory questions are:

Whether a generic product contains one or both active ingredients;
Which Orange Book patents are listed for the reference product;
Whether the applicant files Paragraph III or Paragraph IV certifications;
Whether the applicant seeks approval for a patented method of use;
Whether the label can omit a patented use through a section viii statement.

What generic launch scenarios exist?

The most likely generic launch scenarios do not directly practice Patent 9,439,901.

Standalone dapagliflozin launch

A generic dapagliflozin product could launch after resolution or expiration of the relevant Farxiga patents. Such a product would not infringe Claim 1 or Claim 2 merely because physicians later prescribe it with sitagliptin.

Standalone sitagliptin launch

A generic sitagliptin product could launch after resolution or expiration of the relevant Januvia patents. It would not meet the claim requiring dapagliflozin unless sold or promoted as part of the claimed combination.

Fixed-dose combination launch

A dapagliflozin-sitagliptin fixed-dose product would face the clearest exposure. A sponsor would need to address the patent through validity, noninfringement, licensing, a settlement, or a delayed launch.

What is the commercial significance and revenue exposure?

The patent’s direct revenue exposure is narrower than the revenue associated with Farxiga or Januvia.

Revenue source	Exposure to Patent 9,439,901
Farxiga monotherapy	Limited
Januvia monotherapy	Limited
Farxiga plus metformin	Limited
Qtern sales	Limited because Qtern contains saxagliptin
Future dapagliflozin-sitagliptin product	Direct
Combination prescribing without a fixed-dose product	Fact-dependent

The patent could become commercially important if a sponsor develops a combination product that pairs the two leading mechanisms. Its current value is primarily defensive and strategic. It can deter a specifically claimed combination during the remaining term, but it does not preserve monopoly control over either franchise independently.

Key Takeaways

U.S. Patent 9,439,901 claims human treatment of obesity and Type 2 diabetes with dapagliflozin plus sitagliptin.
The patent is a combination-use patent, not a compound patent.
The claims do not specify dose, ratio, route, formulation, or treatment duration.
“Comprising” may permit additional active ingredients, subject to the other claim elements.
Standalone generic dapagliflozin and sitagliptin products generally do not practice the claims.
Qtern is outside the literal claim scope because it contains saxagliptin rather than sitagliptin.
The patent is not the principal Orange Book barrier for Farxiga or Januvia.
The expected ordinary patent-term expiration is approximately November 2030, subject to USPTO term adjustments or disclaimers.
The main commercial risk concerns a fixed-dose or otherwise integrated dapagliflozin-sitagliptin product.
The main validity risk is obviousness based on the known combination of SGLT2 and DPP-4 inhibition.

FAQs About U.S. Patent 9,439,901

Does Patent 9,439,901 cover Farxiga alone?

No. The claims require both dapagliflozin and sitagliptin in the claimed pharmaceutical composition.

Does Patent 9,439,901 cover Januvia alone?

No. Januvia contains sitagliptin but not dapagliflozin.

Does Qtern infringe Patent 9,439,901?

Qtern contains dapagliflozin and saxagliptin. It does not contain sitagliptin, so it does not literally satisfy the specific DPP-4 inhibitor limitation.

Can a generic company sell dapagliflozin and sitagliptin separately?

The patent claims a composition containing both ingredients. Separate-product sales require a fact-specific analysis, particularly concerning labeling, co-packaging, promotional conduct, and the manner of administration.

Is Patent 9,439,901 a biosimilar barrier?

No. Both dapagliflozin and sitagliptin are small-molecule drugs regulated through the generic-drug framework rather than the biosimilar pathway.

References

AstraZeneca. (2024). Farxiga prescribing information. U.S. Food and Drug Administration.
Merck Sharp & Dohme LLC. (2024). Januvia prescribing information. U.S. Food and Drug Administration.
U.S. Food and Drug Administration. (2024). Approved drug products with therapeutic equivalence evaluations. Center for Drug Evaluation and Research.
U.S. Patent and Trademark Office. (2016). U.S. Patent No. 9,439,901, methods of treating obesity and diabetes. Washington, DC.
U.S. Food and Drug Administration. (2024). Orange Book: Approved drug products with therapeutic equivalence evaluations. Center for Drug Evaluation and Research.
U.S. Food and Drug Administration. (2024). Qtern prescribing information. Center for Drug Evaluation and Research.

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Patented / Exclusive Use	Submissiondate
Msd Sub Merck	STEGLUJAN	ertugliflozin; sitagliptin phosphate	TABLET;ORAL	209805-001	Dec 19, 2017		RX	Yes	No	⤷ Start Trial	⤷ Start Trial				AN ADJUNCT TO DIET AND EXERCISE TO IMPROVE GLYCEMIC CONTROL IN ADULTS WITH TYPE 2 DIABETES	⤷ Start Trial
Msd Sub Merck	STEGLUJAN	ertugliflozin; sitagliptin phosphate	TABLET;ORAL	209805-002	Dec 19, 2017		RX	Yes	Yes	⤷ Start Trial	⤷ Start Trial				AN ADJUNCT TO DIET AND EXERCISE TO IMPROVE GLYCEMIC CONTROL IN ADULTS WITH TYPE 2 DIABETES	⤷ 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
African Regional IP Organization (ARIPO)	3099	⤷ Start Trial
Australia	2010310956	⤷ Start Trial
Canada	2777857	⤷ Start Trial
Costa Rica	20120289	⤷ Start Trial
Cyprus	1115949	⤷ Start Trial
>Country	>Patent Number	>Estimated Expiration	>Supplementary Protection Certificate	>SPC Country	>SPC Expiration

Details for Patent: 9,439,901

Which drugs does patent 9,439,901 protect, and when does it expire?

Summary for Patent: 9,439,901