US Patent 8,697,125: Linagliptin Tablet Claims, Patent Scope, Expiration Risk, and Generic Design-Arounds

US Patent No. 8,697,125 protects a specific immediate-release linagliptin tablet architecture and a manufacturing process for producing it. The patent does not broadly claim linagliptin, all linagliptin formulations, or all DPP-4 inhibitor tablets. Its core requirements are a linagliptin-containing granule with microcrystalline cellulose and mannitol, combined with an external tableting aid containing magnesium stearate and additional microcrystalline cellulose.

The strongest infringement risk applies to tablets that reproduce the claimed excipient split, particularly where microcrystalline cellulose is present both inside the granule and outside the granule in the tableting aid. Claims 2 through 6 add quantitative, mechanical, dissolution, binder, and formulation limitations. Claims 7 and 9 create separate process and product-by-process exposure.

What drug does US Patent 8,697,125 cover?

The active ingredient identified in the claims is linagliptin, chemically described as:

2-[[6-[(3R)-3-amino-1-piperidinyl]-3,4-dihydro-3-methyl-2,4-dioxo-1(2H)-pyrimidinyl]methyl]benzonitrile.

Linagliptin is a dipeptidyl peptidase-4 inhibitor marketed in the United States as Tradjenta by Boehringer Ingelheim and as part of combination products such as Jentadueto and Glyxambi. The claims cover linagliptin or a salt of linagliptin, but only in the claimed tablet and granulation context.

Item	Scope under US 8,697,125
Active ingredient	Linagliptin or a salt
Product type	Tablet
Dosage form	Solid oral tablet
Active ingredient limitation	Linagliptin must be the sole pharmaceutically active ingredient
Core granule excipients	Microcrystalline cellulose and mannitol
External tableting aid	Magnesium stearate and microcrystalline cellulose
Optional binder	Hydroxypropylcellulose
Express exclusion	Polyvinylpyrrolidone is excluded by claim 6
Performance limitation	At least 85% dissolved in 15 minutes under specified conditions
Manufacturing limitation	Mixing the granule and tableting aid, followed by punching

What are the independent claims in US 8,697,125?

Claim 1: composition claim

Claim 1 requires a tablet containing two defined components:

A granule containing linagliptin or a salt, microcrystalline cellulose, and mannitol.
A tableting aid containing magnesium stearate and microcrystalline cellulose.

The tablet must contain linagliptin as its sole pharmaceutically active ingredient.

The claim uses the term “comprising.” That language generally permits additional inactive ingredients unless another limitation excludes them. It does not, however, permit a second pharmaceutically active ingredient because the claim expressly requires linagliptin to be the sole pharmaceutically active ingredient.

The critical structural limitation is the presence of microcrystalline cellulose in two locations:

Within the linagliptin granule.
Within the external tableting-aid fraction.

A formulation using microcrystalline cellulose only inside the granule, or only outside the granule, would present a potential noninfringement position against claim 1. The strength of that position would depend on whether the product’s manufacturing records and analytical evidence establish the location and function of the excipient.

Claim 7: manufacturing method claim

Claim 7 covers a process that:

Mixes the defined linagliptin granule with the defined tableting aid.
Punches the resulting mixture into tablets.

The granule must contain linagliptin or a salt, microcrystalline cellulose, and mannitol. The tableting aid must contain magnesium stearate and microcrystalline cellulose.

Claim 7 is narrower than a general claim to manufacturing a linagliptin tablet, but it may capture a process even where the final dosage form is not independently easy to distinguish from competing products. Manufacturing records, batch instructions, excipient addition points, and process validation documents would be central to an infringement analysis.

Claim 9: product-by-process claim

Claim 9 covers a tablet obtained by the method of claim 7. It incorporates the process limitations through the phrase “obtained by the method.”

The practical scope of claim 9 depends on how the claim is interpreted in the relevant litigation. Product-by-process claims generally raise two issues:

Whether the product must exhibit structural or functional characteristics resulting from the claimed process.
Whether a structurally identical product made by a different process falls within the claim.

A generic manufacturer cannot assume that changing the manufacturing sequence eliminates all risk. The product’s structural composition and the legal treatment of the process language would both matter.

What dependent limitations materially narrow the patent?

Claim	Added limitation	Commercial significance
2	Microcrystalline cellulose in granule: 5-40 wt%; external microcrystalline cellulose: 2-20 wt%	Creates quantitative formulation boundaries
3	Tablet hardness of 70-200 N	Targets mechanical properties of the finished tablet
4	At least 85% dissolution in 15 minutes using specified media and Paddle Method	Creates a rapid-release performance limitation
5	Hydroxypropylcellulose as binding aid	Narrows binder selection
6	No polyvinylpyrrolidone	Excludes a common pharmaceutical binder
8	Same microcrystalline cellulose ranges as claim 2	Narrows the manufacturing method
9	Tablet obtained by claim 7 process	Extends process-based protection to the resulting tablet

Claims 2 and 8 are especially important because they quantify the two separate microcrystalline cellulose fractions. A product may contain the same ingredients but fall outside those claims if the relevant amounts are outside the stated ranges.

What formulations are protected by US 8,697,125?

The patent protects a formulation with the following design:

Linagliptin is granulated with microcrystalline cellulose and mannitol.
The resulting granule is blended with an external tableting aid.
The external tableting aid contains magnesium stearate and additional microcrystalline cellulose.
The blend is compressed into a tablet.

Claim 1 does not require hydroxypropylcellulose. Claim 5 adds it as an optional narrowing limitation. Claim 1 also does not require the dissolution or hardness values found in claims 3 and 4.

The claim does not expressly require:

A particular linagliptin dose.
A particular salt form beyond the generic “salt thereof.”
A particular tablet shape.
A film coating.
A particular commercial brand.
A particular packaging configuration.
A particular tablet color.
A specific granulation technology such as wet granulation or dry granulation.

Because the claim is open-ended, additional inactive ingredients may be present unless they conflict with a specific limitation. Claim 6 creates an express no-polyvinylpyrrolidone limitation for the narrower embodiment.

How strong is the patent estate for linagliptin tablets?

US 8,697,125 is a formulation patent, not the principal compound patent for linagliptin. Its commercial value therefore depends on whether a competing manufacturer must use the claimed excipient architecture to achieve an acceptable tablet.

Strengths

It covers the finished tablet, not only an intermediate.
It claims both the composition and the manufacturing process.
It requires microcrystalline cellulose in two distinct formulation roles.
It includes a broad independent claim without the hardness and dissolution restrictions.
It covers linagliptin salts.
The “sole pharmaceutically active ingredient” limitation fits single-agent linagliptin products.

Weaknesses

The patent does not cover every linagliptin tablet.
The required mannitol and dual-location microcrystalline cellulose structure provides design-around opportunities.
The claims do not expressly cover combination products containing metformin, empagliflozin, or another active ingredient.
Claims 2, 3, and 4 impose technical limitations that require proof through formulation records and testing.
The process claims depend on how the accused manufacturer actually makes the tablet.
Prior-art risk is concentrated in conventional tablet excipients, granulation methods, and rapid-dissolution formulations.

The patent is strongest against a product that uses the same commercial formulation blueprint. It is weaker against a manufacturer that changes the granule composition, replaces mannitol, moves all microcrystalline cellulose into one formulation phase, or uses a distinct compression process.

What are the principal design-around strategies?

A generic manufacturer could evaluate several formulation pathways:

Excipient substitution

Replace mannitol with another diluent, such as lactose, dibasic calcium phosphate, or a different polyol. The substitution must preserve acceptable stability, flow, compressibility, and dissolution.

Microcrystalline cellulose relocation

Use microcrystalline cellulose only in the intragranular phase or only in the external phase. This approach directly targets the claim requirement that microcrystalline cellulose be present in both component A and component B.

Alternative binder system

Use a binder other than hydroxypropylcellulose where claim 5 is at issue. Claim 1 does not require hydroxypropylcellulose, so binder substitution alone would not avoid claim 1.

Polyvinylpyrrolidone-containing formulation

Claim 6 excludes polyvinylpyrrolidone, but adding polyvinylpyrrolidone would not necessarily avoid claim 1 because claim 1 does not prohibit it. A PVP formulation would need to be assessed against the broader independent claim.

Different tableting aid

Avoid a tableting-aid fraction containing both magnesium stearate and microcrystalline cellulose. This strategy targets claim 1 and the process claim, although magnesium stearate could still be used elsewhere depending on the formulation architecture.

Combination product

A tablet containing a second active ingredient could avoid the “sole pharmaceutically active ingredient” limitation. That approach would not eliminate risk under other linagliptin formulation patents and would not be commercially relevant to a single-agent generic.

Quantitative design-around

For claims 2 and 8, place one or both microcrystalline cellulose fractions outside the claimed ranges. This strategy requires robust controls because manufacturing variability could move a product into the claimed range.

When does US 8,697,125 lose exclusivity?

US 8,697,125 was granted on April 15, 2014. Its enforceable term is generally calculated from the applicable earliest nonprovisional filing date, subject to patent-term adjustment and any applicable terminal disclaimer. A grant date alone does not establish the expiration date.

The ordinary term for a utility patent filed after June 8, 1995, is 20 years from the earliest effective nonprovisional filing date, not 20 years from issuance.[1] The operative expiration date should therefore be confirmed from the USPTO patent record, including:

Earliest effective U.S. or international filing date.
Patent-term adjustment.
Terminal disclaimers.
Any correction or reexamination certificate.
Any patent-term extension, if applicable.

Based on the patent’s 2014 grant timing and the known development period for linagliptin, the relevant nominal term is expected to fall in the late 2020s, subject to the official USPTO term calculation. Patent expiration does not itself establish generic launch permission if other Orange Book-listed patents or regulatory exclusivities remain relevant.

What is the Orange Book status of US 8,697,125?

A patent’s inclusion in the FDA Orange Book is product-specific. The FDA lists patents submitted by an NDA holder for an approved drug and approved use; it does not create a universal list of every patent that may be asserted against a product.[2]

For linagliptin, the relevant Orange Book review should distinguish:

The Tradjenta NDA.
Combination-product NDAs such as Jentadueto and Glyxambi.
Compound patents.
Salt or crystalline-form patents.
Formulation patents.
Method-of-use patents.
Pediatric exclusivity.
Any delisting, expiration, or patent-use-code changes.

US 8,697,125 should not be assumed to protect every linagliptin product solely because it claims a linagliptin tablet. The precise Orange Book status requires comparison of the patent’s claims with the FDA-listed product, dosage form, strength, and patent-use code.

What Paragraph IV risks exist for a linagliptin generic?

An ANDA applicant seeking approval before expiration of an Orange Book-listed patent may submit a Paragraph IV certification alleging that the patent is invalid, unenforceable, or not infringed.[3]

For US 8,697,125, the likely technical positions would include:

The proposed tablet does not contain mannitol in the claimed granule.
Microcrystalline cellulose is not present in both required formulation components.
The proposed tablet does not use magnesium stearate and microcrystalline cellulose as the claimed external tableting aid.
Linagliptin is not the sole active ingredient.
The claimed weight ranges are not met.
The proposed process does not mix and punch the components as required.
The claims are invalid over prior art involving linagliptin tablets, granulation, mannitol, microcrystalline cellulose, and magnesium stearate.
The dissolution or hardness limitations are not satisfied where those claims are asserted.

The principal litigation risk is factual. A formulation can appear different in its marketing description while still using the claimed excipient arrangement in confidential manufacturing documents.

Which companies are challenging linagliptin patent rights?

The supplied claims do not identify any Paragraph IV applicant, district-court action, settlement, or license. Those matters cannot be attributed to a company from the patent claims themselves.

A reliable competitive review should separate:

ANDA applicants for single-agent linagliptin.
Applicants for linagliptin-metformin products.
Applicants for linagliptin-empagliflozin products.
Authorized generic arrangements.
Patent settlements and launch dates.
District-court litigation under 35 U.S.C. § 271(e)(2).
Federal Circuit appeals.
FDA approval dates and any 30-month stays.

A settlement involving a compound patent may not resolve exposure under a separate formulation patent. Conversely, a formulation patent may have limited commercial impact if the generic uses a noninfringing formulation or if the patent is not listed for the relevant NDA.

How does US 8,697,125 compare with other linagliptin patent categories?

Patent category	Typical subject matter	Relevance to US 8,697,125
Compound patent	Linagliptin molecule and salts	Broader active-ingredient protection
Crystalline-form patent	Specific solid form or polymorph	Protects API form rather than tablet architecture
Formulation patent	Excipients, granules, dissolution, compression	Directly overlaps with US 8,697,125
Method-of-use patent	Treatment of diabetes or related conditions	Covers use, not necessarily tablet composition
Manufacturing patent	API synthesis or purification	Creates supply-chain and CMC barriers
Combination-product patent	Linagliptin plus another active ingredient	More relevant to Jentadueto or Glyxambi
Device or packaging patent	Delivery or presentation system	Usually separate from tablet composition

US 8,697,125 is most relevant to a single-agent linagliptin tablet made with the claimed granulation and compression design. It does not replace analysis of API, crystalline-form, combination-product, or method-of-use patents.

What is the likely generic launch scenario?

A generic launch depends on the complete patent and exclusivity set rather than this patent alone.

Scenario	Patent position	Commercial result
Early Paragraph IV approval	Generic defeats or settles all blocking patents	Possible launch before ordinary patent expiry
Formulation design-around	Generic avoids US 8,697,125 but faces other patents	Launch depends on remaining rights
First-filer settlement	Launch date set by agreement	Entry may occur before nominal expiration
Post-expiration entry	No enforceable blocking patent remains	Conventional generic competition
Combination-product launch	Separate patents and exclusivities apply	Entry timing differs from single-agent Tradjenta
At-risk launch	Generic launches before final resolution	Exposure to damages and injunction risk

Revenue exposure should be assessed by product, not by molecule alone. Single-agent Tradjenta revenue, fixed-dose combination revenue, and regional sales may be protected by different patent groups and different regulatory filings.

What is the geographic coverage of US 8,697,125?

US 8,697,125 has U.S. legal effect only. Corresponding applications may exist in other jurisdictions, but a U.S. patent does not establish protection in Europe, Japan, China, Canada, or other markets.

A multinational freedom-to-operate review should map:

National-phase counterparts.
Grant and lapse status.
Local patent-term calculations.
Supplementary protection certificates.
National Orange Book equivalents.
Local generic approval and patent-linkage rules.
Regional settlements or licenses.

The same formulation may be protected in one country and unprotected in another because claim scope, prosecution amendments, validity rulings, and expiration dates differ.

Key Takeaways

US 8,697,125 is a linagliptin formulation and manufacturing patent.
Claim 1 requires a linagliptin granule containing microcrystalline cellulose and mannitol, plus an external tableting aid containing magnesium stearate and additional microcrystalline cellulose.
Linagliptin must be the sole pharmaceutically active ingredient.
Claims 2 through 6 add cellulose ranges, tablet hardness, rapid dissolution, hydroxypropylcellulose, and a no-PVP limitation.
Claim 7 independently targets the mixing and punching process.
Claim 9 extends protection to a tablet obtained by that process.
The principal design-around opportunities involve changing mannitol, relocating microcrystalline cellulose, altering the tableting-aid composition, or using a different manufacturing sequence.
The patent’s exact expiration date requires the USPTO term record, including patent-term adjustment and any terminal disclaimer.
Orange Book listing and Paragraph IV exposure must be assessed by NDA, dosage form, strength, and patent-use code.
The patent is narrower than a linagliptin compound patent but potentially important for a generic that copies the reference product’s granulation architecture.

Frequently Asked Questions

Does US 8,697,125 cover linagliptin API by itself?

No. The claims require a tablet or a tablet-manufacturing process. They do not broadly claim linagliptin API, linagliptin salts in all forms, or all pharmaceutical uses of linagliptin.

Can a tablet with microcrystalline cellulose infringe the patent?

Yes, potentially. The relevant issue is whether microcrystalline cellulose is present in both the linagliptin-containing granule and the external tableting aid, together with the other required limitations.

Does claim 6 prohibit all polyvinylpyrrolidone-containing products?

Claim 6 covers the narrower embodiment in which the tablet does not contain polyvinylpyrrolidone. Adding polyvinylpyrrolidone may avoid claim 6, but it does not automatically avoid claim 1.

Do claims 3 and 4 apply to every tablet covered by claim 1?

No. Claims 3 and 4 are narrower dependent claims. A tablet can fall within claim 1 without meeting the 70-200 N hardness range or the specified 15-minute dissolution threshold.

Is a linagliptin-metformin tablet covered by claim 1?

Not if it contains metformin as a second pharmaceutically active ingredient. Claim 1 requires linagliptin to be the sole pharmaceutically active ingredient in the tablet. Separate combination-product patents may still apply.

References

United States Patent and Trademark Office. (2024). Patent term adjustment. https://www.uspto.gov/patents/laws/patent-term-adjustment
U.S. Food and Drug Administration. (2024). Approved drug products with therapeutic equivalence evaluations. https://www.fda.gov/drugsatfda
U.S. Food and Drug Administration. (2024). Abbreviated new drug application submissions: Refuse-to-receive standards. https://www.fda.gov/drugs/guidance-compliance-regulatory-information
United States Patent and Trademark Office. (2014). U.S. Patent No. 8,697,125, pharmaceutical composition.
U.S. Code, 35 U.S.C. §§ 154, 271(e)(2), 505.

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Patented / Exclusive Use	Submissiondate
Takeda Pharms Usa	NESINA	alogliptin benzoate	TABLET;ORAL	022271-001	Jan 25, 2013		RX	Yes	No	⤷ Start Trial	⤷ Start Trial	Y				⤷ Start Trial
Takeda Pharms Usa	NESINA	alogliptin benzoate	TABLET;ORAL	022271-002	Jan 25, 2013		RX	Yes	No	⤷ Start Trial	⤷ Start Trial	Y				⤷ Start Trial
Takeda Pharms Usa	NESINA	alogliptin benzoate	TABLET;ORAL	022271-003	Jan 25, 2013		RX	Yes	Yes	⤷ Start Trial	⤷ Start Trial	Y				⤷ 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

Foriegn Application Priority Data
Foreign Country	Foreign Patent Number	Foreign Patent Date
Japan	2007-023584	Feb 1, 2007

PCT Information
PCT Filed	January 30, 2008	PCT Application Number:	PCT/JP2008/051896
PCT Publication Date:	August 07, 2008	PCT Publication Number:	WO2008/093878

Country	Patent Number	Estimated Expiration	Supplementary Protection Certificate	SPC Country	SPC Expiration
Argentina	065096	⤷ Start Trial
Canada	2677193	⤷ Start Trial
Chile	2008000280	⤷ Start Trial
European Patent Office	2124901	⤷ Start Trial
Spain	2639854	⤷ Start Trial
>Country	>Patent Number	>Estimated Expiration	>Supplementary Protection Certificate	>SPC Country	>SPC Expiration

Summary for Patent: 8,697,125