Litigation Details for Vanda Pharmaceuticals Inc. v. Teva Pharmaceuticals USA, Inc. (D. Del. 2020)

Vanda Pharmaceuticals Inc. v. Teva Pharmaceuticals USA, Inc. (D. Del. 2020)

Docket		Date Filed	2020-08-21
Court	District Court, D. Delaware	Date Terminated	2022-12-14
Cause	35:1 Patent Infringement	Assigned To	Colm Felix Connolly
Jury Demand	None	Referred To
Patents	10,610,510; 10,610,511
Link to Docket	External link to docket

Details for Vanda Pharmaceuticals Inc. v. Teva Pharmaceuticals USA, Inc. (D. Del. 2020)

Date Filed	Document No.	Description	Snippet	Link To Document
2020-08-21				External link to document

Vanda Pharmaceuticals Inc. v. Teva Pharmaceuticals USA, Inc. Litigation Summary, 1:20-cv-01104

Last updated: August 15, 2026

Vanda Pharmaceuticals prevailed against Teva in Hatch-Waxman litigation involving proposed generic tasimelteon, the active ingredient in Hetlioz. The dispute centered on Vanda’s method-of-use patents covering treatment of Non-24-Hour Sleep-Wake Disorder and related circadian-rhythm conditions. The U.S. District Court for the District of Delaware found Teva’s proposed product would infringe asserted claims and rejected Teva’s invalidity defenses. The Federal Circuit affirmed the core judgment in 2023. [1]

What is Vanda Pharmaceuticals v. Teva Pharmaceuticals, 1:20-cv-01104?

The case was a patent infringement action filed by Vanda Pharmaceuticals Inc. against Teva Pharmaceuticals USA Inc. after Teva submitted an Abbreviated New Drug Application seeking approval to market generic tasimelteon.

Item	Detail
Court	U.S. District Court for the District of Delaware
Civil action	No. 1:20-cv-01104
Plaintiff	Vanda Pharmaceuticals Inc.
Defendant	Teva Pharmaceuticals USA Inc.
Product	Proposed generic tasimelteon
Brand product	Hetlioz
NDA holder	Vanda Pharmaceuticals
Regulatory pathway	ANDA with Paragraph IV certifications
Primary patents in appellate decision	U.S. Patent Nos. 8,586,610 and 9,730,910
Federal Circuit decision	Vanda Pharmaceuticals Inc. v. Teva Pharmaceuticals USA Inc., 57 F.4th 142 (Fed. Cir. 2023)

Vanda alleged that Teva’s proposed labeling would induce infringement of method-of-treatment claims. The asserted patents covered administering tasimelteon to treat Non-24-Hour Sleep-Wake Disorder and specified patient populations.

What patents protect Hetlioz and tasimelteon?

The litigation principally involved two Vanda patents: U.S. Patent No. 8,586,610 and U.S. Patent No. 9,730,910.

U.S. Patent No. 8,586,610

The ’610 patent concerns methods of treating Non-24-Hour Sleep-Wake Disorder with tasimelteon. The patent claims treatment protocols that include administering tasimelteon to patients diagnosed with the disorder.

U.S. Patent No. 9,730,910

The ’910 patent also covers tasimelteon treatment methods. Its claims address patient treatment and dosing conditions associated with circadian-rhythm disorders.

The patents were method-of-use patents rather than composition-of-matter patents. That distinction drove the litigation. Teva’s proposed product could be chemically equivalent to tasimelteon while still creating infringement exposure through the proposed prescribing information.

Hetlioz patent portfolio

Vanda’s broader Hetlioz portfolio includes additional patents relating to tasimelteon formulations, treatment methods, patient populations and indications. Patent scope and enforceability must be assessed patent by patent. The Federal Circuit appeal in this action focused on the asserted claims of the ’610 and ’910 patents. [1]

What was Teva’s Paragraph IV challenge?

Teva’s ANDA included Paragraph IV certifications asserting that the relevant Vanda patents were invalid, unenforceable or would not be infringed by Teva’s proposed generic product.

A Paragraph IV certification is an assertion under the Hatch-Waxman Act that a listed patent does not block approval of the proposed generic. Filing the certification can trigger patent litigation under 35 U.S.C. § 271(e)(2), which treats submission of the ANDA as an act of infringement for purposes of resolving the patent dispute before commercial launch.

Vanda responded by filing the Delaware action. The filing triggered the statutory 30-month stay of FDA approval, subject to court decisions and other statutory events.

What were the central legal issues in the Vanda v. Teva case?

The case presented four principal issues.

Did Teva’s proposed label induce infringement?

Vanda argued that Teva’s proposed label would encourage physicians to prescribe tasimelteon in a manner covered by the asserted method claims.

Teva argued that the proposed label did not expressly instruct physicians to perform every claimed step and that physicians would not necessarily practice the patented methods. The Federal Circuit rejected that position. It held that the district court had sufficient evidence to find that Teva’s proposed labeling would encourage and lead to infringement. [1]

The decision is significant because it applied induced-infringement principles to a generic label that did not need to reproduce the patent claims verbatim. The relevant question was whether the label, taken as a whole, encouraged the claimed use.

Were the asserted claims invalid for lack of written description?

Teva argued that Vanda’s patent specifications did not adequately describe the full scope of the claimed methods and patient populations.

The written-description defense is particularly important for pharmaceutical method claims. A specification may disclose a treatment concept without adequately demonstrating possession of every claimed patient group, dosing condition or clinical result.

The district court rejected Teva’s written-description challenge. The Federal Circuit affirmed the finding that the specifications adequately supported the asserted claims. [1]

Were the claims enabled?

Teva also challenged enablement, arguing that the patents required undue experimentation across the claimed scope.

The court found that the patent disclosures enabled the claimed tasimelteon treatment methods. The Federal Circuit did not disturb that conclusion.

Were the claims obvious?

Teva relied on prior art concerning melatonin-receptor agonists, circadian-rhythm disorders and tasimelteon. The court rejected the obviousness defense. The appellate decision left the validity determination intact. [1]

What did the Federal Circuit decide in 2023?

The Federal Circuit affirmed the district court’s central conclusions that:

1. Teva’s proposed ANDA product and labeling would infringe the asserted method claims.
2. The asserted claims were not invalid for lack of written description.
3. The asserted claims were not invalid for lack of enablement.
4. The asserted claims were not shown to be obvious.

The decision was issued as Vanda Pharmaceuticals Inc. v. Teva Pharmaceuticals USA Inc., 57 F.4th 142 (Fed. Cir. 2023). [1]

The appellate holding preserved Vanda’s ability to use the asserted patents to delay or prevent approval of Teva’s proposed generic tasimelteon product until the relevant patent barriers expired or were otherwise removed.

What was the litigation timeline?

Date	Event
2014	FDA approved Hetlioz for Non-24-Hour Sleep-Wake Disorder in totally blind individuals. [2]
2018	U.S. Patent No. 9,730,910 issued.
2020	Vanda filed the Delaware action after Teva’s Paragraph IV ANDA certification.
2020-2022	The parties litigated infringement, written description, enablement and obviousness.
2022	The District of Delaware entered judgment favoring Vanda on the principal patent issues.
Jan. 2023	The Federal Circuit issued its decision in 57 F.4th 142. [1]
After appellate judgment	The asserted patent-based barriers remained enforceable subject to further proceedings, patent expiration and any separate regulatory developments.

What is the Orange Book status of Hetlioz?

Hetlioz is an FDA-approved small-molecule drug listed in the Orange Book. Orange Book-listed patents may include patents directed to the drug substance, drug product or approved method of use. [3]

The Vanda patents at issue in the litigation were method-of-use patents. Their commercial impact depended on whether Teva’s proposed labeling induced use covered by those claims.

The Orange Book status should be separated from FDA exclusivity:

• Patent listing identifies potentially enforceable patent rights.
• Regulatory exclusivity is a separate FDA protection.
• A Paragraph IV certification challenges the listed patent, not necessarily the FDA’s scientific approval of tasimelteon.
• A court judgment may prevent or delay generic approval even when the ANDA otherwise satisfies FDA requirements.

When does tasimelteon lose patent exclusivity?

The ’610 patent has a listed term extending into 2032, subject to the official patent term calculation, any patent-term adjustment, and any applicable patent-term extension. The ’910 patent has a related term based on its priority and filing history. The precise Orange Book expiration dates control for FDA approval purposes. [3]

The commercial entry date for a generic tasimelteon product may differ from the nominal expiration date because of:

• 30-month-stay calculations;
• pediatric exclusivity;
• patent-term adjustment;
• patent-term extension;
• district court or appellate injunctions;
• a litigation settlement;
• an authorized generic arrangement; or
• FDA action on the ANDA.

The Vanda decision did not eliminate the patents. It upheld their use against Teva’s proposed generic product.

Did Vanda and Teva settle the litigation?

The reported Federal Circuit decision reflects adjudication rather than a publicly reported settlement disposing of the central appeal. The appellate record treated the dispute as a judgment on infringement and validity.

No settlement-based launch date should be assumed from the case number alone. A confidential or later commercial agreement could alter entry timing without changing the appellate opinion.

Which companies are challenging Hetlioz exclusivity?

Teva was the defendant in this action and challenged Vanda’s patent rights through an ANDA Paragraph IV certification.

The case does not establish that every future generic applicant would infringe the same claims. A later applicant could:

• submit a different label;
• carve out a patented indication;
• challenge different Orange Book patents;
• assert a noninfringement position based on a different dosage regimen; or
• rely on a different invalidity theory.

The Vanda decision increases the risk for generic applicants whose labels materially encourage the patented tasimelteon use.

How strong is the Vanda patent estate for Hetlioz?

The estate was strong in this litigation for three reasons.

First, the patents covered clinically relevant use of the approved drug rather than peripheral manufacturing details. Method claims can directly target the use that a generic label seeks to promote.

Second, the court accepted Vanda’s induced-infringement theory. A generic applicant cannot avoid liability solely by omitting the exact language of a patent claim if the label, prescribing information and pharmacologic instructions collectively encourage the claimed use.

Third, Vanda defeated multiple validity challenges. The written-description and obviousness findings reduced the immediate risk that the asserted patents would be removed before expiration.

The estate also has limits. Method-of-use patents are narrower than composition-of-matter patents. Their enforcement depends on the relationship between the patent claims, the approved label, physician conduct and the proposed generic labeling.

What generic launch risks exist for tasimelteon?

Full-label launch risk

A generic applicant seeking approval for the same principal tasimelteon indication faces substantial risk if its label encourages the patented treatment method. The Vanda decision supports a finding of induced infringement in that setting.

Skinny-label risk

A carve-out of a patented indication may reduce infringement exposure. The result depends on the exact claim language and whether the remaining label still encourages the patented use.

Physician-prescribing risk

The risk is not limited to express label language. Evidence concerning physician behavior, prescribing instructions, clinical practice and the product’s intended use can support induced infringement.

Patent-expiry risk

The strongest launch opportunity arises when the relevant method patents expire or when a generic applicant obtains a judgment of noninfringement or invalidity. Until then, a generic approval may face statutory and injunctive barriers.

Are biosimilar issues relevant to Hetlioz?

No. Hetlioz contains tasimelteon, a small-molecule active ingredient. The relevant competitive pathway is an ANDA for a generic drug, not a biosimilar application under the Public Health Service Act.

The principal regulatory and patent risks are therefore:

• ANDA approval;
• Paragraph IV litigation;
• method-of-use patent enforcement;
• Orange Book listings;
• labeling carve-outs; and
• generic substitution.

What manufacturing and formulation IP barriers apply?

The Vanda v. Teva appeal primarily concerned method-of-use patents, not a manufacturing-process dispute.

A separate freedom-to-operate review would need to assess:

• tasimelteon synthesis patents;
• crystalline or polymorphic forms;
• formulation and dosage-form patents;
• stability and excipient claims;
• tablet or capsule manufacturing processes;
• analytical methods; and
• patents covering additional indications.

Manufacturing patents can create commercial risk even when a generic applicant defeats use patents. Conversely, a method-of-use judgment does not necessarily establish infringement of unrelated process or formulation patents.

How does Hetlioz compare with competing circadian-rhythm products?

Tasimelteon competes in a narrower market than broad insomnia products. Its principal differentiation is melatonin-receptor activity and FDA-approved use in Non-24-Hour Sleep-Wake Disorder.

Product	Active ingredient	Main category	Regulatory pathway	Key patent risk
Hetlioz	Tasimelteon	Circadian-rhythm treatment	NDA	Method-of-use and product-specific patents
Rozerem	Ramelteon	Insomnia treatment	NDA	Different molecule and indication
Melatonin products	Melatonin	Supplement or nonprescription products	Not equivalent to Hetlioz NDA	No direct ANDA equivalence
Generic tasimelteon	Tasimelteon	Generic circadian-rhythm treatment	ANDA	Orange Book patents and label-induced infringement

The competitive threat from generic tasimelteon is more direct than competition from ramelteon or over-the-counter melatonin because an approved generic would be pharmaceutically equivalent or bioequivalent to Hetlioz, subject to FDA requirements.

What was the commercial exposure from the litigation?

The litigation protected Vanda’s ability to maintain branded pricing and market share for Hetlioz against the specific Teva ANDA. The exposure included:

• loss of branded sales after generic entry;
• price erosion;
• formulary substitution;
• payer-driven generic conversion;
• inventory and channel disruption; and
• reduced value of future tasimelteon indications.

Because Non-24-Hour Sleep-Wake Disorder is a specialized indication, the number of treated patients may be smaller than in mass-market insomnia. That can reduce unit-volume exposure but increase the importance of specialist prescribing, reimbursement and uninterrupted supply.

The record does not provide a reliable basis for assigning a specific revenue loss figure solely from the case docket. Any valuation should use Vanda’s reported Hetlioz revenue, expected generic discounting and the actual approved generic launch date.

Key Takeaways

• Vanda sued Teva in Delaware after Teva filed a Paragraph IV ANDA for generic tasimelteon.
• The litigation focused on U.S. Patent Nos. 8,586,610 and 9,730,910.
• The patents covered methods of treating Non-24-Hour Sleep-Wake Disorder and related circadian-rhythm conditions.
• The District of Delaware found infringement and rejected Teva’s written-description, enablement and obviousness defenses.
• The Federal Circuit affirmed the core judgment in Vanda Pharmaceuticals Inc. v. Teva Pharmaceuticals USA Inc., 57 F.4th 142 (Fed. Cir. 2023).
• The case is relevant to generic-label strategy because the court accepted induced infringement based on the proposed label and surrounding evidence.
• Hetlioz is a small-molecule drug, so biosimilar law does not apply.
• Generic entry remains dependent on patent expiration, FDA approval, any later litigation outcome and any undisclosed commercial agreement.

FAQs About Vanda Pharmaceuticals v. Teva

What drug was at issue in Vanda v. Teva?

The dispute involved tasimelteon, marketed by Vanda as Hetlioz.

Was Vanda’s patent portfolio composition-of-matter based?

The principal patents in the appellate litigation were method-of-use patents, not a basic composition-of-matter patent covering tasimelteon itself.

What type of FDA filing triggered the case?

Teva submitted an ANDA containing Paragraph IV certifications challenging Vanda’s listed patents.

Does the Federal Circuit decision apply to all generic tasimelteon products?

No. The ruling directly addressed Teva’s proposed product, label and litigation record. A different applicant could present different claims, labeling or defenses.

Does this case involve biosimilar substitution?

No. Tasimelteon is a small-molecule drug. Generic substitution would proceed through the ANDA framework rather than the biosimilar pathway.

References

1. U.S. Court of Appeals for the Federal Circuit. (2023). Vanda Pharmaceuticals Inc. v. Teva Pharmaceuticals USA, Inc., 57 F.4th 142.
2. U.S. Food and Drug Administration. (2014). FDA approves Hetlioz for Non-24-Hour Sleep-Wake Disorder.
3. U.S. Food and Drug Administration. (n.d.). Approved drug products with therapeutic equivalence evaluations, Orange Book: Hetlioz.