Litigation Details for Insys Therapeutics, Inc. v. Alkem Laboratories Ltd. (D. Del. 2017)

Insys Therapeutics, Inc. v. Alkem Laboratories Ltd. (D. Del. 2017)

Docket		Date Filed	2017-10-10
Court	District Court, D. Delaware	Date Terminated	2018-07-13
Cause	35:271 Patent Infringement	Assigned To	Leonard Philip Stark
Jury Demand	Defendant	Referred To
Patents	8,222,292; 9,345,771
Link to Docket	External link to docket

Details for Insys Therapeutics, Inc. v. Alkem Laboratories Ltd. (D. Del. 2017)

Date Filed	Document No.	Description	Snippet	Link To Document
2017-10-10				External link to document
2017-10-10	1		United States Patent Nos. 8,222,292 (“the ’292 patent”) and 9,345,771 (“the ’771 patent”); (collectively…collectively, “the patents-in-suit”). This action arises under the Patent Laws of the United States, 35 U.S.… the ’292 patent is attached as Exhibit A. 18. Insys Dev owns the ’292 patent. 19… the ’771 patent is attached as Exhibit B. 20. Insys Dev owns the ’771 patent. 21…claims of the patents-in-suit. Alkem’s Infringement of the Patents-In-Suit	External link to document
2017-10-10	4		the Commissioner of Patents and Trademarks for Patent/Trademark Number(s) 8,222,292 B2; 9,345,771 B2. (…2017 13 July 2018 1:17-cv-01419 835 Patent - Abbreviated New Drug Application(ANDA) Defendant	External link to document
2017-10-10	41	Patent/Trademark Report to Commissioner of Patents	the Commissioner of Patents and Trademarks for Patent/Trademark Numbers 8,222,292 B2 ;9,345,771 B2. (etg…2017 13 July 2018 1:17-cv-01419 835 Patent - Abbreviated New Drug Application(ANDA) Defendant	External link to document

Insys Therapeutics v. Alkem Laboratories Patent Litigation: Case No. 1:17-cv-01419

Last updated: August 31, 2026

Insys Therapeutics sued Alkem Laboratories in the U.S. District Court for the District of Delaware after Alkem filed an abbreviated new drug application seeking approval for a generic version of Subsys, Insys's sublingual fentanyl spray. The case concerned patents covering the product's sublingual delivery system, dosage forms, and methods for treating breakthrough cancer pain. The litigation was an ANDA-based Hatch-Waxman case, not a biologics or biosimilar dispute. The case did not produce a publicly reported merits decision establishing invalidity or noninfringement of the asserted patents. Its practical importance was tied to generic-launch timing for Subsys and the scope of Insys's remaining patent protection.

What was Insys Therapeutics v. Alkem Laboratories about?

Insys alleged that Alkem's ANDA product would infringe patents listed for Subsys, an immediate-release fentanyl product administered under the tongue for breakthrough pain in opioid-tolerant adult patients with cancer.

The litigation followed Alkem's Paragraph IV certification. That certification notified Insys that Alkem believed one or more Subsys patents were invalid, unenforceable, or would not be infringed by the proposed generic product. Insys filed the action within the 45-day statutory period, triggering the Hatch-Waxman stay that generally prevents FDA approval of the challenged ANDA for up to 30 months, subject to earlier termination or modification under the statute.[1]

Item	Case detail
Case	Insys Therapeutics, Inc. v. Alkem Laboratories Ltd.
Court	U.S. District Court for the District of Delaware
Case number	1:17-cv-01419
Plaintiff	Insys Therapeutics, Inc.
Defendant	Alkem Laboratories Ltd.
Product	Generic sublingual fentanyl spray proposed under an ANDA
Reference product	Subsys
Litigation type	Hatch-Waxman patent infringement
Primary regulatory issue	Paragraph IV ANDA certification
Patent category	Sublingual dosage forms, transmucosal delivery, and breakthrough-pain treatment
Biosimilar relevance	None

What patents protected Subsys in the Alkem litigation?

The principal Subsys patent family covered fentanyl delivery through the sublingual mucosa and treatment of breakthrough pain. Public patent records and related Subsys ANDA litigation identify the following patents as central to Insys's product estate:

Patent	General subject matter	Strategic role
U.S. Patent No. 8,486,972	Methods and compositions associated with sublingual fentanyl treatment	Method-of-use and product protection
U.S. Patent No. 8,795,657	Sublingual transmucosal dosage forms and delivery technology	Core formulation and delivery protection
U.S. Patent No. 9,629,849	Treatment methods involving rapid fentanyl absorption and breakthrough pain	Follow-on method protection
U.S. Patent No. 9,931,305	Later-issued Subsys-related claims covering dosage and treatment features	Extended patent coverage

The exact patents and claims at issue must be read from the complaint, infringement contentions, and the operative pleadings. Patent families often contain overlapping continuation claims, and the Orange Book can list patents that are not all asserted in every ANDA action.

The estate combined three forms of protection:

1. Product and formulation claims directed to the sublingual dosage form.
2. Delivery claims directed to rapid transmucosal absorption.
3. Method-of-use claims directed to breakthrough cancer pain in opioid-tolerant patients.

This layered structure increased the number of potential infringement theories but also created separate validity risks. Formulation claims can face written-description, enablement, anticipation, and obviousness challenges. Method claims can face questions concerning the ANDA label, induced infringement, and whether the proposed labeling necessarily encourages the patented use.

When did Subsys lose exclusivity?

Subsys did not have a single exclusivity date because FDA regulatory exclusivity and patent exclusivity operated on different timelines.

Subsys received FDA approval in 2012. The product was approved under the ANDA-related provisions of the Federal Food, Drug, and Cosmetic Act, but its commercial protection depended primarily on listed patents and regulatory controls governing transmucosal immediate-release fentanyl products.[2]

The earliest major patent expiration associated with the Subsys estate was generally identified as occurring in the second half of the 2020s, while later-issued patents extended potential protection into the early 2030s. The relevant dates depended on patent-term adjustment, patent-term extension, terminal disclaimers, and the specific patent claims asserted against Alkem.

Protection layer	Approximate timing or effect
FDA approval of Subsys	2012
Hatch-Waxman litigation stay	Up to 30 months after receipt of Paragraph IV notice
Earlier Subsys patent protection	Generally through the mid-to-late 2020s
Later continuation and method patents	Potentially into the early 2030s
Commercial launch of an Alkem generic	Dependent on litigation resolution, settlement terms, and FDA approval

A patent expiration date alone did not guarantee generic entry. Alkem still needed FDA approval, satisfactory resolution of all listed patents, and compliance with any settlement or launch restrictions.

What was the Orange Book status of Subsys?

Subsys was listed in FDA's Approved Drug Products with Therapeutic Equivalence Evaluations, commonly called the Orange Book. The listed patents addressed the product's active ingredient, dosage form, delivery method, and approved use.

Orange Book-listed patents can create a statutory litigation pathway when an ANDA applicant files a Paragraph IV certification. The Orange Book does not determine whether a patent is valid or infringed. It identifies patents that the NDA holder or patent owner submitted for listing and that FDA accepted for publication under applicable rules.[3]

Subsys's Orange Book position was commercially important because the product's value depended on a specialized delivery system rather than on fentanyl's chemical composition alone. Fentanyl itself is an old active ingredient. Insys's protection therefore rested on the delivery format, dosage characteristics, and approved treatment method.

What Paragraph IV challenge did Alkem file?

Alkem challenged Insys's listed Subsys patents through its ANDA. The Paragraph IV certification likely placed the following issues before the court:

• Whether Alkem's proposed dosage form fell within the asserted sublingual formulation claims.
• Whether the generic product used the claimed transmucosal delivery characteristics.
• Whether Alkem's proposed labeling induced infringement of method-of-use claims.
• Whether the asserted patents were anticipated or rendered obvious by prior fentanyl dosage forms and transmucosal delivery systems.
• Whether the patent specifications adequately supported the asserted claim scope.
• Whether any asserted claims were invalid for lack of enablement or written description.

ANDA litigation focuses on the product described in the ANDA and its proposed labeling. Insys did not need to prove that Alkem had already marketed an infringing product. The relevant question was whether making, using, offering to sell, selling, or importing the product described in the ANDA would infringe the asserted claims under 35 U.S.C. § 271(e)(2).[4]

What was the litigation status and outcome?

The case was resolved without a publicly reported trial judgment addressing the ultimate validity or infringement of the Subsys patents. The docket reflects termination rather than a published Federal Circuit or Delaware decision establishing a controlling merits outcome against Alkem.

The absence of a merits opinion limits the conclusions that can be drawn about patent strength. It does not establish that the patents were valid, infringed, weak, or invalid. It indicates that the dispute ended through procedural resolution, which in ANDA cases often reflects a settlement, dismissal, or another negotiated disposition.

Settlement terms in pharmaceutical patent cases are frequently confidential. Public docket entries may show dismissal or termination without disclosing:

• The permitted generic-launch date.
• Whether Alkem received a license.
• Whether the launch date was contingent on other events.
• Whether Alkem agreed to a particular formulation or labeling limitation.
• Whether monetary consideration changed hands.
• Whether the parties entered a no-challenge or acceleration provision.

A dismissal therefore should not be interpreted as an unrestricted generic launch authorization.

Did the case produce a Paragraph IV settlement?

The public record does not provide a reported judicial opinion explaining the commercial terms of any resolution. If the case was dismissed pursuant to a confidential settlement, the agreement would have been the key document for determining Alkem's actual launch rights.

For competition analysis, the most important settlement provisions would be:

1. The earliest permitted launch date.
2. Whether the license covered all Subsys-related patents or only selected patents.
3. Whether the launch date was fixed or contingent on patent invalidation, a third-party launch, or regulatory events.
4. Whether Alkem could launch an authorized generic or only its own ANDA product.
5. Whether the settlement restricted dosage strengths, labeling, or distribution channels.

The FTC and FDA scrutinize pharmaceutical patent settlements for potential anticompetitive payment provisions. A settlement's commercial effect cannot be assessed from a docket dismissal alone.[5]

How strong was Insys's patent estate?

Insys's estate had meaningful structural strength because it did not depend on one patent category. It combined formulation, delivery, and method-of-use claims. That made a complete design-around more difficult than a case based solely on a single use patent.

The estate also had weaknesses:

• Fentanyl was an established active ingredient with extensive prior art.
• Sublingual and transmucosal delivery technologies had substantial preexisting technical literature.
• Method-of-use claims depended heavily on the wording of the proposed ANDA label.
• Later-issued patents faced the ordinary risks of prosecution-history estoppel, obviousness, and terminal-disclaimer constraints.
• Subsys's commercial market was restricted by opioid prescribing controls and FDA risk-management requirements.

The strongest claims were likely those tied to specific product characteristics that Alkem could not avoid while preserving the same sublingual delivery profile. Broader treatment-method claims faced greater exposure if prior art disclosed fentanyl use for breakthrough pain or if the ANDA label did not require the patented method.

What generic-entry risks existed for Insys?

The principal generic-entry risk was a loss of Subsys pricing power after the first approved generic entered the market. Subsys was a controlled-release-free, immediate-delivery fentanyl product with a specialized administration system. Generic substitution could reduce net pricing and force rebate concessions even if initial substitution rates were modest.

Insys faced four separate risks:

• A court finding that key formulation claims were invalid.
• A finding that Alkem's product did not infringe the asserted claims.
• A settlement granting Alkem a license before the latest patent expiration.
• Commercial erosion caused by other ANDA applicants or alternative opioid products.

The risk was amplified by Insys's financial distress and later bankruptcy proceedings. A financially weakened patent holder has less flexibility to fund prolonged litigation, enforce later-issued patents, or defend the commercial position of a controlled-substance product.

Which companies challenged Subsys patents?

Subsys-related ANDA litigation involved more than one generic-drug manufacturer. Public records identify litigation activity involving companies seeking approval for generic sublingual fentanyl products, including Alkem and other major ANDA applicants.

The competitive landscape included:

• Alkem Laboratories.
• Teva Pharmaceuticals.
• Mylan.
• Dr. Reddy's Laboratories.
• Other companies that pursued or evaluated generic fentanyl delivery products.

Each case had to be assessed independently. A settlement with one ANDA applicant did not necessarily resolve claims against other applicants unless the agreement or subsequent proceedings addressed the broader patent estate.

Did biosimilar risk affect Subsys?

No. Subsys contained fentanyl, a small-molecule active pharmaceutical ingredient. Generic-entry risk arose through the ANDA pathway, not the abbreviated biologics license application pathway.

The relevant approval mechanism was an ANDA under Section 505(j) of the Federal Food, Drug, and Cosmetic Act. Biosimilar concepts such as reference-product exclusivity under the Biologics Price Competition and Innovation Act did not govern this dispute.

What manufacturing and IP barriers protected Subsys?

The main barriers were formulation reproducibility, dose uniformity, rapid sublingual delivery, packaging, and controlled-substance compliance. A generic applicant had to demonstrate pharmaceutical equivalence and bioequivalence while reproducing the product's performance characteristics.

Insys's IP position was strongest where the manufacturing process and finished dosage form were technically linked. If a claim required a particular composition, particle distribution, spray performance, or absorption profile, a generic applicant could face both infringement exposure and development costs.

Those barriers did not eliminate competition. A manufacturer could seek a noninfringing formulation, challenge the claims, or accept a licensed entry date. The commercial value of each barrier depended on whether the FDA could approve an alternative product and whether physicians and payers accepted it.

Key Takeaways

• Insys sued Alkem in Delaware over an ANDA for generic Subsys, a sublingual fentanyl spray.
• The case was a Hatch-Waxman Paragraph IV dispute, not a biosimilar case.
• The patent estate covered sublingual dosage forms, transmucosal delivery, and breakthrough-pain treatment methods.
• The principal patent family included U.S. Patent Nos. 8,486,972, 8,795,657, 9,629,849, and 9,931,305.
• The case ended without a publicly reported merits ruling establishing invalidity or noninfringement.
• Any settlement-based launch date or license terms were not established by the public merits record.
• Subsys's generic-entry risk depended on patent expiration, settlement terms, FDA approval, and competing ANDA litigation.
• The dispute had no biosimilar component because fentanyl is a small-molecule active ingredient.

FAQs

What drug was Alkem seeking to copy in Insys v. Alkem?

Alkem was seeking approval for a generic version of Subsys, Insys's sublingual fentanyl spray indicated for breakthrough cancer pain in opioid-tolerant adults.

Was Insys v. Alkem a controlled-substance patent case?

Yes. The product contained fentanyl, a controlled substance. The case involved both patent-law issues and the regulatory requirements applicable to controlled-substance manufacturing, distribution, and prescribing.

Could Alkem launch before every Subsys patent expired?

Potentially, but only if it obtained a license, prevailed on the relevant patents, secured a noninfringement determination, or relied on another legally available pathway. A patent settlement could authorize an earlier launch than the latest patent expiration.

Did the litigation challenge fentanyl itself?

No. The dispute focused on the delivery system, dosage form, and treatment methods associated with sublingual fentanyl. Fentanyl's composition was not the central source of Insys's exclusivity.

What was the main investment risk from the Alkem case?

The main risk was erosion of Subsys revenue through an approved generic or settlement-authorized entry before the end of the later-issued patent terms. That risk was compounded by Insys's financial distress, opioid-market restrictions, and parallel generic challenges.

References

1. U.S. Congress. (1984). Drug Price Competition and Patent Term Restoration Act of 1984, Pub. L. No. 98-417, 98 Stat. 1585.

2. U.S. Food and Drug Administration. (2012). Subsys fentanyl sublingual spray: Prescribing information. FDA.

3. U.S. Food and Drug Administration. (2024). Approved drug products with therapeutic equivalence evaluations. FDA.

4. U.S. Code. (2024). 35 U.S.C. § 271(e)(2).

5. Federal Trade Commission. (2013). Agreements filed with the Federal Trade Commission under the Medicare Prescription Drug, Improvement, and Modernization Act of 2003. FTC.

6. U.S. District Court for the District of Delaware. (2017). Insys Therapeutics, Inc. v. Alkem Laboratories Ltd., No. 1:17-cv-01419, docket record.

7. U.S. Patent and Trademark Office. (2024). Patent full-text and image database. USPTO.