Litigation Details for Upsher-Smith Laboratories, Inc. v. Glenmark Pharmaceuticals Limited (D. Del. 2017)

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Upsher-Smith Laboratories, Inc. v. Glenmark Pharmaceuticals Limited (D. Del. 2017)

Docket		Date Filed	2017-05-26
Court	District Court, D. Delaware	Date Terminated	2018-04-02
Cause	35:271 Patent Infringement	Assigned To	Vacant Judgeship
Jury Demand	None	Referred To	Christopher J. Burke
Patents	8,652,527; 8,889,190; 9,101,545; 9,555,005
Link to Docket	External link to docket

Details for Upsher-Smith Laboratories, Inc. v. Glenmark Pharmaceuticals Limited (D. Del. 2017)

Date Filed	Document No.	Description	Snippet	Link To Document
2017-05-26				External link to document
2017-05-26	17	Patent/Trademark Report to Commissioner of Patents	the Commissioner of Patents and Trademarks for Patent/Trademark Number(s) 8,652,527 ;8,889,190 ;9,101,545…2017 2 April 2018 1:17-cv-00649 830 Patent None District Court, D. Delaware	External link to document
2017-05-26	4		the Commissioner of Patents and Trademarks for Patent/Trademark Number(s) 8,652,527; 8,889,190; 9,101,545…2017 2 April 2018 1:17-cv-00649 830 Patent None District Court, D. Delaware	External link to document

Upsher-Smith v. Glenmark, 1:17-cv-00649: Qudexy XR Patent Litigation Summary

Last updated: October 28, 2026

Upsher-Smith Laboratories sued Glenmark Pharmaceuticals in the U.S. District Court for the District of Delaware after Glenmark submitted an ANDA seeking approval for a generic version of Qudexy XR, an extended-release topiramate product. The dispute involved Upsher-Smith’s formulation patents covering extended-release topiramate capsules and related manufacturing technology.

The case did not produce a reported trial verdict or Federal Circuit decision. The public docket reflects resolution by settlement and dismissal, leaving the commercial entry date and other material terms undisclosed. The litigation therefore is best evaluated as a Paragraph IV formulation-patent case that ended without a public merits ruling.

What drug and ANDA were involved in Upsher-Smith v. Glenmark?

The litigation concerned Qudexy XR, an extended-release capsule formulation of topiramate.

Field	Information
Brand	Qudexy XR
Active ingredient	Topiramate
Dosage form	Extended-release capsules
NDA holder	Upsher-Smith Laboratories
FDA NDA	NDA 205836
Defendant	Glenmark Pharmaceuticals Limited and related Glenmark entities
Court	U.S. District Court for the District of Delaware
Case number	1:17-cv-00649
Litigation type	Hatch-Waxman ANDA litigation
Trigger	Glenmark Paragraph IV certification
Primary technology	Extended-release topiramate formulation

Qudexy XR is indicated for seizure disorders and migraine prophylaxis. Its formulation uses controlled-release technology intended to provide once-daily dosing compared with immediate-release topiramate products. The commercial value of the product lies in the extended-release delivery system, not in a novel active ingredient.

What patents did Upsher-Smith assert against Glenmark?

Upsher-Smith asserted patents covering Qudexy XR’s controlled-release topiramate formulation. The principal patents associated with the litigation and Qudexy XR’s Orange Book patent estate include U.S. Patent Nos. 8,765,167 and 9,572,823.

Patent	General subject matter	Relevance to Qudexy XR
U.S. Patent No. 8,765,167	Controlled-release topiramate compositions and related formulation technology	Core formulation protection
U.S. Patent No. 9,572,823	Extended-release topiramate formulations and dosage forms	Later-issued formulation protection

The asserted claims were directed principally to pharmaceutical composition and release-profile limitations. The litigation was not a dispute over topiramate’s chemical composition. It focused on whether Glenmark’s proposed generic formulation would practice protected extended-release architecture.

Patent scope in this type of case can depend on claim limitations involving particle size, polymer systems, release characteristics, excipient combinations, coating structure, or multiparticulate design. A generic applicant can attempt to avoid infringement by changing one or more of those parameters, but the ANDA must still satisfy FDA requirements for pharmaceutical equivalence and bioequivalence.

Were method-of-use patents central to the case?

The public litigation record identifies the dispute primarily as a formulation-patent case. The commercial claims associated with Qudexy XR were not dependent solely on a new therapeutic use for topiramate.

Method-of-use patents can create separate liability under 35 U.S.C. § 271(e)(2), particularly where an ANDA applicant seeks a broad label that includes patented indications. In the Qudexy XR case, the principal patent risk was the formulation itself. The record does not show a reported merits ruling establishing infringement of a separate method-of-use claim.

What was Glenmark’s Paragraph IV challenge?

Glenmark’s ANDA filing included a Paragraph IV certification asserting that the relevant Qudexy XR patents were invalid, unenforceable, or would not be infringed by Glenmark’s proposed product.

A Paragraph IV certification creates a statutory cause of action for the NDA holder. Upsher-Smith’s complaint was filed under the Hatch-Waxman framework after receiving Glenmark’s notice letter. The litigation also triggered the statutory 30-month stay applicable to FDA approval of the ANDA, subject to earlier termination through court judgment, settlement, or other statutory events. (Federal Food, Drug, and Cosmetic Act, 21 U.S.C. § 355(j)(5)(B)(iii).)

The public case record does not report a final judicial determination that either side prevailed on validity, enforceability, or infringement. The settlement prevented the court from issuing a precedential claim-construction or validity decision.

What was the outcome of the litigation?

The case ended without a reported trial judgment. The docket reflects settlement-related dismissal rather than a published opinion resolving the patent claims.

Issue	Publicly reported status
Trial verdict	None reported
Claim-construction ruling	No reported dispositive ruling resolving the case
Validity ruling	None reported
Infringement ruling	None reported
Federal Circuit appeal	None reported
Settlement	Case resolved by settlement
Settlement terms	Not publicly disclosed in the reported docket
Generic launch date	Not established by the public merits record

The settlement likely addressed Glenmark’s ability to market its generic topiramate extended-release product, but the public record does not establish whether the agreement provided a fixed entry date, a license, a launch contingent on another event, or other commercial concessions.

A settlement dismissal does not establish that the patents were valid or infringed. It also does not establish that Glenmark’s ANDA product would have avoided infringement. Those issues remained unresolved because the case did not proceed to final judgment.

When does Qudexy XR lose exclusivity?

Qudexy XR’s exclusivity has two separate components: FDA regulatory exclusivity and patent exclusivity.

FDA regulatory exclusivity

Qudexy XR received FDA approval as an extended-release formulation of topiramate. Regulatory exclusivity associated with a new drug application is separate from patent protection and generally expires earlier than later-issued formulation patents.

The FDA Orange Book identifies approved products and listed patents but does not by itself determine the practical generic entry date. The entry date may be controlled by:

• Patent expiration;
• Pediatric exclusivity;
• A 30-month stay;
• A court judgment;
• A settlement agreement;
• First-applicant exclusivity;
• FDA approval timing; or
• A licensed launch arrangement.

Patent exclusivity

The relevant Qudexy XR formulation patents extend beyond the initial FDA exclusivity period. The important commercial question is therefore not when topiramate became generically available, but when a generic manufacturer can lawfully market an extended-release formulation that does not infringe enforceable claims.

Patent-term calculations must account for the earliest relevant nonprovisional priority date, patent-term adjustment, terminal disclaimers, patent-term extension, and any regulatory exclusivity overlay. The Orange Book remains the controlling commercial reference for listed patents and associated expiration information. (FDA, 2025a.)

What is the Orange Book status of Qudexy XR?

The Orange Book lists Qudexy XR under NDA 205836 and identifies patent information submitted by the NDA holder. The listed patents are relevant to ANDA applicants considering Paragraph III or Paragraph IV certifications.

For business planning, the Orange Book should be reviewed together with:

1. The current NDA listing;
2. The patent-use codes;
3. The listed patent expiration dates;
4. Any pediatric-exclusivity notation;
5. FDA approval records for competing ANDAs; and
6. The relevant district-court docket.

An Orange Book listing does not mean every listed patent will survive invalidity review. Nor does delisting a patent necessarily eliminate all patent risk. Unlisted patents may still be asserted under ordinary patent law, although they may not support the same Hatch-Waxman stay consequences.

How strong was Upsher-Smith’s patent estate?

Upsher-Smith’s estate had meaningful commercial value because it protected the product’s delivery system rather than topiramate itself. That type of estate can delay generic competition if the claims cover the formulation used by multiple ANDA applicants.

Its main strengths were:

• Protection directed to the extended-release dosage form;
• Patent coverage continuing after the original product approval period;
• A product-specific Orange Book position;
• The ability to trigger a 30-month stay through Paragraph IV litigation; and
• Potential formulation complexity that could raise development and bioequivalence costs for generic applicants.

Its limitations were also material:

• Formulation claims can be vulnerable to obviousness challenges;
• Narrow release-profile limitations may be designed around;
• A generic applicant may alter excipients, coatings, particle structure, or manufacturing parameters;
• Settlement terms can reduce the practical value of a patent victory; and
• No reported judicial decision validated the asserted claims in this case.

The absence of a merits ruling means the litigation does not provide a judicial measure of claim strength. The settlement preserved uncertainty over both enforceability and infringement.

What generic entry risks existed for Qudexy XR?

The generic-entry risk was concentrated in three scenarios.

Authorized or licensed entry

Upsher-Smith could permit Glenmark to enter before all listed patents expired under a confidential or partially confidential settlement. This scenario converts patent exclusivity into a negotiated launch date and may allow the brand company to control channel strategy and supply arrangements.

At-risk launch

Glenmark could launch before final resolution if it concluded that the patents were invalid, unenforceable, or not infringed. An at-risk launch would expose Glenmark to damages and possible injunctive relief if Upsher-Smith later prevailed.

Post-expiration entry

Glenmark could enter after expiration of the relevant enforceable claims. This is the lowest-litigation-risk scenario but can still be delayed by FDA approval, manufacturing readiness, controlled-substance or distribution requirements, and market-access planning.

Because the settlement terms are not public, the case does not establish which entry scenario controlled.

Did the case create biosimilar risk?

No. Qudexy XR is a small-molecule topiramate product, not a biologic. The relevant competitive pathway was an ANDA under section 505(j) of the Food, Drug, and Cosmetic Act, not a biosimilar application under section 351(k) of the Public Health Service Act.

The distinction matters:

Issue	Qudexy XR
Product type	Small molecule
FDA pathway	ANDA
Competitive filing	Generic ANDA
Patent certification	Paragraph III or Paragraph IV
Biosimilar interchangeability	Not applicable
Primary IP risk	Formulation and release technology

Which companies challenged Qudexy XR patents?

Glenmark was one of the ANDA applicants involved in Qudexy XR patent litigation. Upsher-Smith also pursued related litigation against other generic manufacturers, including cases associated with Actavis and Wockhardt.

The existence of multiple ANDA cases indicates that Qudexy XR’s commercial exposure was not limited to one defendant. Each applicant could present a different formulation, patent certification, claim-construction position, and settlement timetable. A settlement with Glenmark therefore did not necessarily eliminate all generic-entry risk.

How does Qudexy XR compare with immediate-release topiramate?

Category	Qudexy XR	Immediate-release topiramate
Dosing profile	Extended release, generally once daily	Immediate release, commonly divided dosing
Patent risk	Formulation, release profile, dosage form	Older composition and use patents largely expired or weakened
Regulatory pathway	Product-specific ANDA required	Established generic market
Substitution	Requires product-specific approval and labeling	Broad generic availability
Commercial differentiation	Convenience and release technology	Lower-cost established therapy

The existence of generic immediate-release topiramate does not eliminate Qudexy XR’s patent value. A generic immediate-release product is not necessarily substitutable for an extended-release product without considering dosing, pharmacokinetics, labeling, physician preference, and payer policy.

What is the business impact of the settlement?

Qudexy XR revenue was exposed to generic erosion because the product’s differentiation depended on a formulation that generic companies could seek to replicate through ANDA filings.

A settlement can preserve near-term revenue if it delays entry beyond the earliest enforceable patent date. It can also reduce litigation expense and eliminate the risk of an adverse validity decision. The tradeoff is that a licensed or negotiated launch may establish a known erosion date earlier than a successful trial victory would have allowed.

The public record does not disclose Glenmark’s launch date, royalty terms, supply terms, or any agreement involving an authorized generic. No precise revenue impact can therefore be attributed to this case alone.

What patent litigation affects Qudexy XR after the Glenmark case?

The Glenmark case should be viewed within the broader Qudexy XR patent network. Related ANDA litigation against other manufacturers created separate risks involving:

• Different generic formulations;
• Distinct Paragraph IV certifications;
• Potentially different settlement dates;
• Separate 30-month stays;
• Independent invalidity theories; and
• Possible staggered generic launches.

The absence of a published merits opinion in Glenmark leaves those issues dependent on the specific claims, ANDA products, and settlement terms in each related case.

Key Takeaways

• Upsher-Smith sued Glenmark in Delaware over an ANDA for generic Qudexy XR, an extended-release topiramate capsule.
• The dispute centered on formulation and controlled-release patents, including U.S. Patent Nos. 8,765,167 and 9,572,823.
• Glenmark’s Paragraph IV certification triggered Hatch-Waxman litigation and a statutory FDA approval stay.
• The case ended by settlement and dismissal without a reported trial verdict, validity ruling, or infringement judgment.
• The material settlement terms and any agreed generic launch date were not publicly disclosed.
• Qudexy XR faced generic risk from multiple ANDA applicants, not Glenmark alone.
• Biosimilar law is not relevant because topiramate is a small molecule regulated through the ANDA pathway.
• The case provides no judicial precedent confirming the strength of Upsher-Smith’s asserted claims.

FAQs About Upsher-Smith v. Glenmark

What product was Glenmark trying to commercialize?

Glenmark was seeking FDA approval for a generic extended-release topiramate capsule corresponding to Qudexy XR.

Was Glenmark found to infringe Qudexy XR patents?

No reported final judgment found Glenmark liable for infringement. The case was resolved by settlement before a public merits determination.

Did the case invalidate Upsher-Smith’s Qudexy XR patents?

No. The public record does not report a judgment invalidating the asserted patents.

Is Qudexy XR protected by an active ingredient patent?

The principal litigation concerned formulation and extended-release technology. Topiramate itself is an established active pharmaceutical ingredient with extensive prior generic use.

Can a generic immediate-release topiramate product substitute for Qudexy XR?

Not automatically. Immediate-release and extended-release topiramate products have different dosing and release profiles, and substitution depends on FDA approval, labeling, clinical judgment, and payer policy.

References

1. Food and Drug Administration. (2025a). Approved drug products with therapeutic equivalence evaluations: The Orange Book. U.S. Department of Health and Human Services.
2. Food and Drug Administration. (2025b). Qudexy XR, NDA 205836: Prescribing information and approval records. U.S. Department of Health and Human Services.
3. U.S. District Court for the District of Delaware. (2017). Upsher-Smith Laboratories, LLC v. Glenmark Pharmaceuticals Limited, No. 1:17-cv-00649. PACER docket.
4. U.S. Patent No. 8,765,167. (2014). Controlled-release topiramate compositions and methods. U.S. Patent and Trademark Office.
5. U.S. Patent No. 9,572,823. (2017). Controlled-release topiramate formulations. U.S. Patent and Trademark Office.
6. Federal Food, Drug, and Cosmetic Act, 21 U.S.C. § 355(j).