Litigation Details for Boehringer Ingelheim Pharmaceuticals Inc. v. Sun Pharmaceutical Industries Limited (D. Del. 2021)

Boehringer Ingelheim Pharmaceuticals Inc. v. Sun Pharmaceutical Industries Limited (D. Del. 2021)

Docket		Date Filed	2021-11-05
Court	District Court, D. Delaware	Date Terminated	2025-07-30
Cause	35:271 Patent Infringement	Assigned To	Colm Felix Connolly
Jury Demand	None	Referred To
Patents	10,258,637; 11,090,323; 7,579,449
Link to Docket	External link to docket

Details for Boehringer Ingelheim Pharmaceuticals Inc. v. Sun Pharmaceutical Industries Limited (D. Del. 2021)

Date Filed	Document No.	Description	Snippet	Link To Document
2021-11-05				External link to document
2021-11-05	3	ANDA Form	Expiration of Patent: U.S. Patent No. 7,579,449 expires on 8/1/2028; U.S. Patent Nos. 10,258,637 and 11,090,323… Supplemental information for patent cases involving an Abbreviated New Drug Application (ANDA) … 5 November 2021 1:21-cv-01573 835 Patent - Abbreviated New Drug Application(ANDA) None	External link to document
2021-11-05	4	Patent/Trademark Report to Commissioner of Patents	Commissioner of Patents and Trademarks for Patent/Trademark Number(s) 7,579,449 B2; 10,258,637 B2; 11,090,… 5 November 2021 1:21-cv-01573 835 Patent - Abbreviated New Drug Application(ANDA) None	External link to document

Boehringer Ingelheim v. Sun Pharmaceutical: Litigation Summary and Patent Analysis, 1:21-cv-01573

Last updated: September 24, 2026

Boehringer Ingelheim Pharmaceuticals, Inc. sued Sun Pharmaceutical Industries Ltd. in the U.S. District Court for the District of Delaware after Sun filed an abbreviated new drug application seeking approval for a generic version of Jardiance, an empagliflozin product. The case is an ANDA patent dispute under the Hatch-Waxman Act. The litigation concerned patents covering empagliflozin and its use in treating Type 2 diabetes, with potential effects on generic entry for Jardiance and related empagliflozin products.[1]

What drug is at issue in Boehringer Ingelheim v. Sun Pharmaceutical?

The dispute concerns empagliflozin, the active ingredient in Jardiance tablets.

Jardiance is an orally administered sodium-glucose cotransporter 2, or SGLT2, inhibitor marketed by Boehringer Ingelheim and Eli Lilly. The FDA approved Jardiance in 2014 for glycemic control in adults with Type 2 diabetes. The FDA later approved additional indications for reducing cardiovascular and renal risks in specified patient populations.[2]

Item	Description
Brand	Jardiance
Active ingredient	Empagliflozin
Dosage form	Oral tablets
Strengths	10 mg and 25 mg
Reference product sponsor	Boehringer Ingelheim Pharmaceuticals, Inc.
Commercial partner	Eli Lilly and Company
Regulatory pathway	ANDA litigation under Hatch-Waxman
Court	U.S. District Court for the District of Delaware
Case number	1:21-cv-01573
Defendant	Sun Pharmaceutical Industries Ltd.

Sun’s ANDA filing triggered a Paragraph IV certification against one or more Orange Book-listed patents for Jardiance. Boehringer responded by filing suit within the statutory 45-day period, creating a 30-month stay of final FDA approval under 21 U.S.C. § 355(j)(5)(B)(iii), subject to statutory exceptions.[3]

What patents protect Jardiance and empagliflozin?

The Jardiance patent estate includes composition-of-matter, formulation, and method-of-use protection. The patents asserted in an ANDA case depend on the Orange Book listings and the specific certifications made by the generic applicant.

Empagliflozin compound protection

The foundational patent estate covers empagliflozin and related glucopyranosyl-substituted compounds. These patents protect the active pharmaceutical ingredient and pharmaceutical compositions containing it.

The principal U.S. patent historically associated with empagliflozin is U.S. Patent No. 8,129,343. The patent claims compounds, including empagliflozin, and pharmaceutical compositions containing those compounds. Its term was affected by patent-term adjustment and, depending on the relevant patent and indication, regulatory exclusivity considerations.[4]

Combination-product protection

Empagliflozin is also marketed in combination products, including:

• Synjardy, empagliflozin plus metformin;
• Synjardy XR, extended-release empagliflozin plus metformin; and
• Glyxambi, empagliflozin plus linagliptin.

Combination products have separate Orange Book listings and may face different patent challenges. A generic application for Jardiance tablets does not automatically authorize a generic version of Synjardy, Synjardy XR, or Glyxambi.

Method-of-use patents

Later-issued patents cover therapeutic uses of empagliflozin, including treatment or risk reduction in patients with cardiovascular disease, heart failure, and chronic kidney disease.

These patents can remain commercially relevant after expiration of the core compound patent. A generic applicant may attempt a section viii statement to carve out patented indications from its label. Whether a carve-out is legally effective depends on the patent claims, the proposed labeling, and whether the remaining label still induces infringement.

What was Sun’s Paragraph IV challenge?

Sun’s Paragraph IV filing asserted that the relevant Jardiance patents were invalid, unenforceable, or would not be infringed by the proposed generic product. A Paragraph IV certification is a statutory notice that the applicant contends an Orange Book-listed patent should not block ANDA approval.[3]

The typical defenses in this category of case include:

1. Non-infringement, based on differences between Sun’s proposed product and the asserted claims.
2. Invalidity for lack of novelty or obviousness.
3. Lack of enablement or written description.
4. Indefiniteness.
5. Improper listing or lack of a statutory nexus between the patent and the listed drug.
6. Non-infringing labeling, particularly for method-of-use patents.

The commercial impact of the challenge depends on whether the asserted patents are core compound patents or narrower use and formulation patents. A successful challenge to the principal compound patent can materially accelerate generic entry. A challenge limited to a narrow indication may leave the main diabetes market protected.

What litigation issues were presented in the case?

The case followed the standard ANDA framework. The central legal question was whether Sun’s filing of an ANDA constituted an artificial act of infringement under 35 U.S.C. § 271(e)(2).

Infringement

Boehringer’s infringement theory likely rested on the fact that Sun’s ANDA proposed approval for a product containing empagliflozin and included labeling corresponding to one or more patented indications.

For composition claims, infringement generally turns on whether Sun’s proposed product contains the claimed active ingredient or composition. For method-of-use claims, the analysis turns on the proposed label and whether the label encourages or requires performance of the claimed method.

The court does not assess commercial sales during the initial Hatch-Waxman action. It evaluates whether the ANDA filing itself creates a statutory cause of action and whether the proposed product would infringe if marketed as described.

Invalidity

The most commercially important validity defenses are obviousness and enablement.

For empagliflozin patents, an obviousness analysis may consider earlier SGLT2 inhibitor disclosures, prior glucoside compounds, pharmacological data, and the motivation to select empagliflozin from a broader genus. The analysis also considers whether the prior art provided a reasonable expectation that the selected compound would have the claimed activity and acceptable pharmaceutical properties.[5]

A patent can survive a broad prior-art field if the challenger cannot establish a reason to select the claimed compound and a reasonable expectation of success. Secondary considerations may include commercial success, industry recognition, unexpected results, and long-felt need, although those factors must have a nexus to the claimed invention.

Claim construction

Claim construction is significant where the asserted patents use functional or chemical limitations. Relevant disputes may concern:

• The scope of the empagliflozin chemical structure;
• Salt, solvate, or crystalline-form limitations;
• The meaning of pharmaceutical-composition terms;
• Patient or disease-state limitations;
• Dosage and administration requirements; and
• The scope of cardiovascular or renal risk-reduction claims.

A claim-construction ruling can determine whether Sun’s proposed product falls within the patent claims without requiring a full trial on every issue.

What is the Orange Book status of Jardiance?

Jardiance has had a multi-layered Orange Book patent estate. The listings have included patents directed to empagliflozin, drug combinations, formulations, and therapeutic uses. Orange Book status can change as patents expire, delist, or are added after later regulatory approvals.[6]

Protection category	Commercial relevance
Empagliflozin compound patents	Can block broad generic Jardiance entry
Pharmaceutical-composition patents	May cover the tablet composition or active ingredient formulation
Combination patents	Apply to Synjardy, Synjardy XR, or Glyxambi rather than Jardiance alone
Cardiovascular-use patents	Can restrict labels for cardiovascular-risk reduction
Heart-failure and renal-use patents	May affect post-approval indications and carve-out strategy
Pediatric exclusivity	Can add six months to qualifying patent terms

The Orange Book does not determine ultimate validity or enforceability. It identifies patents that the reference-product sponsor has submitted to FDA as allegedly covering the approved drug or an approved use. A district court determines infringement, validity, and enforceability in the ANDA action.

When does Jardiance lose exclusivity?

Jardiance does not have one single loss-of-exclusivity date. The practical date depends on the patent challenged, the type of approval sought, pediatric exclusivity, litigation outcomes, and any settlement or license granted to the generic applicant.

The principal commercial barrier has been the empagliflozin patent estate, which has been reported as extending into the late 2020s. Later method-of-use patents can affect particular indications after the core composition protection ends. FDA regulatory exclusivity and patent protection operate separately.

Exclusivity timeline

Event	Date or period
FDA approval of Jardiance	2014
Likely first-wave ANDA litigation	2021 onward
Core patent protection	Late 2020s, depending on patent and adjustment
Potential broad generic entry	Dependent on patent outcomes and settlement terms
Later indication protection	May extend beyond core compound protection
Pediatric exclusivity	May add six months where applicable

A generic company may obtain FDA approval before commercial launch if a patent settlement permits a future entry date. FDA approval and market entry are separate events.

What patent litigation affects Jardiance generic entry?

Boehringer and Lilly have faced multiple ANDA challenges involving Jardiance and related empagliflozin products. The competitive field includes major generic manufacturers that have filed ANDAs or pursued patent challenges against SGLT2 inhibitor products.

The relevant litigation risks include:

• Patent invalidity rulings that could open the market before the listed expiration date;
• Non-infringement findings limited to a particular applicant’s formulation or label;
• Settlements granting licensed entry before patent expiry;
• At-risk launches followed by damages claims;
• Regulatory delays caused by the 30-month stay; and
• Separate litigation involving Synjardy or other combination products.

A court decision involving one generic applicant does not necessarily resolve every later applicant’s case. Different ANDA formulations, labels, certifications, or patent claims can produce different outcomes.

Did Boehringer and Sun reach a settlement?

The public litigation record must be reviewed for any consent judgment, dismissal, settlement notice, or license agreement entered in this specific action. A Hatch-Waxman case may terminate through dismissal without the full economic terms becoming public.

Settlement terms can include:

• A licensed future entry date;
• A royalty-bearing license;
• A no-authorized-generic commitment;
• Restrictions on launch or supply;
• Covenants not to sue;
• Agreement on patent validity or infringement positions; and
• Provisions covering later-issued patents.

The absence of a reported trial judgment does not establish that Sun received immediate market access. In pharmaceutical patent cases, dismissal commonly reflects a confidential settlement or a negotiated resolution tied to a future launch date.

How strong is the Jardiance patent estate?

The estate is commercially strong when assessed as a portfolio rather than by one patent.

Strengths

The portfolio has several protective layers:

• Foundational compound protection for empagliflozin;
• Multiple approved indications;
• Combination-product patents;
• Later-issued cardiovascular, heart-failure, and renal-use patents;
• Significant regulatory and clinical-development investment; and
• A high-value commercial product with broad physician adoption.

Weaknesses

The main vulnerabilities are typical of mature small-molecule estates:

• Core patents face obviousness attacks based on earlier SGLT2 chemistry;
• Later use patents may be vulnerable to carve-outs;
• Patent claims may cover only specified patient groups or endpoints;
• Generic applicants can challenge different patents in separate proceedings;
• A narrow label may avoid infringement of selected method claims; and
• Patent expiration creates a predictable entry point for multiple ANDA applicants.

The strongest barrier is generally the patent that covers the active ingredient or a mandatory component of the proposed generic product. Method-of-use patents are more dependent on labeling and may be less effective against a product approved with a restricted label.

What generic launch scenarios exist for Sun?

Sun’s launch options fall into four principal categories.

Entry after patent expiry

Sun may launch after the relevant patent or patent term extension expires. This is the lowest litigation-risk scenario but may delay entry until other generic manufacturers are ready.

Licensed entry

Sun may enter under a confidential or public settlement license before complete expiration of the patent estate. The launch date may be earlier than the nominal expiration date but later than the date of FDA approval.

At-risk launch

Sun could launch before final resolution of all patent rights. This would expose the company to damages, injunctive relief, and potential loss of market share if the patent holder prevails.

Carved-out indication

Sun may seek approval for a label that omits one or more patented uses. This strategy is more viable where the remaining indications support a commercially meaningful market and the label does not encourage the patented method.

How does the case compare with other SGLT2 inhibitor patent disputes?

Jardiance competes with Farxiga, marketed by AstraZeneca, and Invokana, marketed by Johnson & Johnson and Mitsubishi Tanabe. Each product has a distinct patent estate.

Product	Active ingredient	Sponsor	Principal patent risk
Jardiance	Empagliflozin	Boehringer Ingelheim and Eli Lilly	Compound, combination, and later-use patents
Farxiga	Dapagliflozin	AstraZeneca	Compound, formulation, and indication patents
Invokana	Canagliflozin	Janssen and Mitsubishi Tanabe	Compound, formulation, and method-of-use patents

Jardiance has substantial commercial exposure because empagliflozin is approved for diabetes, heart failure, and chronic kidney disease-related indications. That expanded label increases revenue opportunity but also creates a larger number of method-of-use patents and carve-out questions.

What is the revenue exposure from generic Jardiance entry?

Jardiance is a major revenue product for Boehringer and Lilly. Generic entry would affect:

• U.S. Jardiance tablet sales;
• Net pricing after multiple generic entrants;
• Combination-product demand;
• Contracting leverage with pharmacy benefit managers;
• Revenue from cardiovascular and renal indications; and
• Lifecycle-management value for Synjardy and related products.

The initial generic entrant may receive a period of commercial advantage if it has a settlement-based launch or first-filer status. Once several ANDA products enter, price erosion is likely to accelerate.

The largest exposure is broad, unrestricted entry into Jardiance tablets. A carved-out label limited to diabetes treatment would have a smaller effect on the full commercial franchise but could still reduce price and volume in the core market.

What is the current legal significance of case 1:21-cv-01573?

The case is significant because it represents a direct challenge to the patent barriers protecting empagliflozin. Its outcome affects the timing and conditions under which Sun can market a generic Jardiance product.

For business planning, the case should be evaluated alongside:

1. The exact Orange Book patents at issue;
2. Any final claim-construction or dispositive rulings;
3. The status of the 30-month stay;
4. The existence of a dismissal, consent judgment, or settlement;
5. Sun’s Paragraph IV certifications;
6. Any carve-out language in Sun’s proposed label; and
7. Separate litigation involving other Jardiance or empagliflozin products.

Key Takeaways

• Boehringer sued Sun in Delaware after Sun filed an ANDA challenging Jardiance-related patent protection.
• The dispute concerns empagliflozin, an SGLT2 inhibitor marketed as Jardiance.
• The relevant patent estate includes compound, formulation, combination, and method-of-use protection.
• Broad generic entry depends primarily on the strength and remaining term of the core empagliflozin patents.
• Later cardiovascular, heart-failure, and renal-use patents may restrict specific labels after core compound protection ends.
• Sun’s commercial options include post-expiry entry, licensed entry, a carved-out indication, or an at-risk launch.
• FDA approval, patent expiry, and actual commercial launch are separate events.
• The case should be analyzed together with the Orange Book listings and other empagliflozin ANDA proceedings.

FAQs

What is case 1:21-cv-01573?

It is a Hatch-Waxman patent infringement action filed in the District of Delaware by Boehringer Ingelheim against Sun Pharmaceutical Industries Ltd. concerning a proposed generic empagliflozin product.

Is Sun allowed to sell generic Jardiance immediately after FDA approval?

Not necessarily. FDA approval does not eliminate patent restrictions. Sun may need to wait for patent expiry, comply with a settlement license, or prevail in the patent litigation.

Can Sun sell a generic version with a narrower label?

Potentially. A section viii carve-out may omit patented indications, but the remaining label must not induce infringement of the asserted method-of-use claims.

Do Jardiance patents also block generic Synjardy?

Not automatically. Synjardy contains empagliflozin and metformin and has separate regulatory and patent considerations. A Jardiance ruling may not resolve Synjardy-related claims.

Why do Jardiance patent expiration dates differ across databases?

Databases may report different dates because of patent-term adjustment, patent-term extension, pediatric exclusivity, later-issued patents, or differences between compound and method-of-use protection.

References

1. U.S. District Court for the District of Delaware. (2021). Boehringer Ingelheim Pharmaceuticals, Inc. v. Sun Pharmaceutical Industries Ltd., No. 1:21-cv-01573.
2. U.S. Food and Drug Administration. (2014). Jardiance approval history and prescribing information.
3. 21 U.S.C. § 355(j); 35 U.S.C. § 271(e)(2).
4. U.S. Patent No. 8,129,343. (2012). Glucopyranosyl-substituted benzene derivatives and medicaments comprising them.
5. 35 U.S.C. §§ 102, 103, 112.
6. U.S. Food and Drug Administration. (2024). Approved Drug Products with Therapeutic Equivalence Evaluations, Orange Book.