United States Patent 10,179,119: Scope, Claims, Expiration, Orange Book Status, and Tasimelteon Patent Landscape

U.S. Patent No. 10,179,119 protects the use of tasimelteon for treating sleep disturbances associated with Smith-Magenis Syndrome (SMS). The patent is assigned to Vanda Pharmaceuticals Inc. and covers once-daily administration before bedtime, with dependent claims directed to sleep outcomes, dosing, administration timing, and maintenance of treatment effects. Its estimated statutory expiration is April 11, 2035, subject to any applicable patent-term adjustment or disclaimer reflected in USPTO records.[1]

The patent is a disease-specific method-of-use patent. It does not claim tasimelteon as a chemical compound, a general melatonin-receptor agonist, or a formulation.

What does U.S. Patent 10,179,119 cover?

The patent covers a method of treating sleep disturbances in a patient diagnosed with Smith-Magenis Syndrome by administering tasimelteon once daily before bedtime.

Core elements of independent claim 1

An accused method must satisfy each of the following limitations:

Claim element	Scope
Patient population	A patient with Smith-Magenis Syndrome
Medical condition	Sleep disturbances
Active ingredient	Tasimelteon
Route or mode	"Internally administering," a term directed to administration into the patient rather than external treatment
Dose frequency	Once daily
Timing	Before bedtime
Therapeutic requirement	An effective amount

The claim does not limit the method to a particular tablet, capsule, liquid, excipient system, or manufacturing process. It also does not expressly require a specific dose, although the dependent claims identify dose ranges and a preferred 20-mg dose.

The practical scope is narrower than a general tasimelteon patent because infringement requires the combination of SMS, sleep disturbances, tasimelteon, once-daily administration, and pre-bedtime dosing.

How do claims 2 through 10 narrow the patent?

Claims 2 through 10 add clinical, dosing, timing, and maintenance limitations.

Claim	Added limitation	Commercial or legal significance
2	Improvement in nighttime sleep	Requires the treatment result to involve nighttime sleep
3	Reduction in the percentage of wake period within the sleep interval	Adds an objective sleep-quality outcome
4	Improvement in specified sleep, behavior, or clinical-impression measures	Broadens the set of qualifying treatment outcomes
5	Tasimelteon dose of about 5 to 100 mg/day	Creates a broad dose-range fallback
6	Dose of about 20 mg/day	Covers the principal Hetlioz dose
7	Administration 30 minutes to 2 hours before bedtime	Defines a pre-bedtime window
8	Administration 30 minutes to 1.5 hours before bedtime	Narrows the timing window
9	Administration one hour before bedtime	Creates a highly specific timing claim
10	Ongoing daily administration maintains treatment effects	Addresses continued treatment rather than a single dose

Claim 4 is drafted as an alternative list. Improvement in any one listed endpoint may satisfy the claim, assuming the other limitations are met. The listed endpoints include total nighttime sleep, nighttime awakenings, sleep onset, wake time, daytime naps, Clinical Global Impression of Change, Clinical Global Impression of Severity, and behavior.

Claim 10 is important for chronic-use products. A generic label that recommends continuous daily administration for SMS could implicate the claim even if the label does not use the same clinical terminology, depending on the approved instructions and the evidence of intended use.

What is the broadest enforceable scope of Patent 10,179,119?

Claim 1 is the commercially important claim. It does not require:

A 20-mg dose
Administration exactly one hour before bedtime
A tablet or capsule
A particular formulation
A particular sleep-measurement instrument
A specified duration of treatment
A particular age range
A particular degree of improvement

The claim does require treatment of a patient with SMS. A method using tasimelteon in a patient with insomnia, Non-24-Hour Sleep-Wake Disorder, autism-related sleep disturbance, or another condition would not fall within claim 1 solely because the patient also happened to have SMS. The SMS diagnosis and the claimed treatment relationship must be established.

The phrase "effective amount" is typical method-of-treatment language. It generally requires an amount that produces the claimed therapeutic purpose, rather than merely any administrable amount. The absence of a fixed dose in claim 1 gives the patentee broader coverage but may create disputes over efficacy, enablement, and claim construction.

What does the patent protect regarding formulation and dosage?

Patent 10,179,119 is primarily a therapeutic-use patent, not a formulation patent.

Formulation coverage

The claims do not expressly require or protect:

An oral tablet formulation
An oral suspension
A liquid dosage form
A controlled-release formulation
A particular salt or polymorph
A specific excipient
A particular particle-size distribution
A manufacturing process

A generic company could therefore design a different formulation and still face infringement if its product is labeled or used for the claimed SMS treatment method.

Conversely, avoiding the patented method by changing the formulation would not necessarily work if the product remains intended for once-daily pre-bedtime SMS treatment.

Dose coverage

Claim 5 covers approximately 5 to 100 mg per day. Claim 6 specifically targets approximately 20 mg per day. "About" permits some variation, but the legally relevant range would depend on claim construction and the evidence surrounding the patent specification and prosecution history.

The 20-mg limitation aligns with the marketed Hetlioz dose for adult Non-24-Hour Sleep-Wake Disorder and the clinical development of tasimelteon in SMS. FDA labeling and clinical use are central evidence for assessing whether a proposed generic label practices claims 5 and 6.[2]

When does Patent 10,179,119 expire?

The patent has an earliest effective nonprovisional filing date associated with the April 11, 2014 priority chain. On that basis, the ordinary 20-year patent term is estimated to run through April 11, 2035, before any patent-term adjustment, terminal disclaimer, or other statutory modification.[1]

Milestone	Date or status
Earliest priority date	April 11, 2014
U.S. patent grant	January 15, 2019
Estimated ordinary expiration	April 11, 2035
Patent type	Method-of-treatment patent
Patent holder	Vanda Pharmaceuticals Inc.
Current status	Issued and unexpired based on the patent record

The exact expiration date should be taken from the USPTO patent-term data because patent-term adjustment can alter the date. Patent expiration is also separate from FDA regulatory exclusivity.

What is the FDA and Orange Book status of tasimelteon?

Tasimelteon is marketed by Vanda as Hetlioz. FDA initially approved Hetlioz capsules in 2014 for Non-24-Hour Sleep-Wake Disorder in totally blind adults. FDA later approved the product for nighttime sleep disturbances in pediatric patients with Smith-Magenis Syndrome.[2,3]

The SMS approval created a direct regulatory pathway for reliance on the SMS indication. It also increased the commercial importance of method-of-use patents covering that indication.

FDA milestones

Event	Significance
2014 Hetlioz approval	Initial approval for Non-24-Hour Sleep-Wake Disorder
2020 SMS-related approval	Expanded regulatory use for nighttime sleep disturbances associated with SMS
Orphan-drug framework	SMS indication may qualify for indication-specific orphan exclusivity
Orange Book listing	Listed patents can create notice and litigation consequences for an ANDA applicant

Patent listing and regulatory exclusivity are distinct. An Orange Book patent may support a Paragraph IV challenge, while orphan exclusivity can independently delay approval for the same indication under the Federal Food, Drug, and Cosmetic Act.[3,4]

The SMS orphan-exclusivity period is generally seven years from approval of the orphan indication, subject to statutory exceptions. A 2020 approval would place the principal seven-year period around 2027. Patent 10,179,119 extends beyond that period and may remain relevant after orphan exclusivity expires.

How strong is the patent estate for the SMS indication?

The estate has meaningful strength because it combines a defined rare-disease population with a specific active ingredient and administration regimen. Its principal limitations are also identifiable.

Strengths

The SMS population is specific and clinically recognizable.
The claim reaches the treatment method regardless of the exact product formulation.
Claim 1 does not require the 20-mg dose or one-hour timing.
Dependent claims provide narrower positions around the commercially relevant regimen.
The claims address both objective sleep outcomes and clinical or behavioral outcomes.
The patent term extends materially beyond the likely orphan-exclusivity period.

Potential vulnerabilities

Tasimelteon was known before the SMS use was claimed.
Sleep disturbance is a known feature of SMS, creating possible obviousness arguments.
The defendant could challenge whether the claimed SMS treatment and dosing regimen were adequately supported by the specification.
"Effective amount," "about," "before bedtime," and "improvement" may generate claim-construction disputes.
A generic applicant may argue that the claims are anticipated or obvious over prior clinical, scientific, or patent literature involving melatonin-receptor agonists, circadian-rhythm disorders, or SMS sleep pathology.
The claims are method claims, so proof of intended use and actual administration can become central.

The strongest litigation position is likely claim 1, supplemented by claims 5, 6, 7, and 9. Claims 3 and 4 may require more evidence concerning the actual sleep or behavioral outcome, but they can provide additional infringement positions when clinical data are available.

What Paragraph IV risks exist for generic tasimelteon?

A generic applicant seeking approval for an SMS indication could face a Paragraph IV certification against listed method-of-use patents, including any Orange Book-listed patent covering the SMS indication.[4]

The likely generic strategies are:

Strategy	Risk profile
Full SMS label	High risk of practicing claims 1 and 10
20-mg once-daily label	High risk of claims 5 and 6
Pre-bedtime administration	Risk under claims 1, 7, 8, and 9
Carve-out of SMS indication	May reduce regulatory exposure but does not eliminate off-label-use or induced-infringement issues
Non-SMS indication only	Lower direct risk from Patent 10,179,119
Different formulation	Does not avoid method claims if the same SMS regimen is promoted or instructed

A Section viii statement or labeling carve-out could remove a patented indication from the generic label if FDA accepts the carve-out. The commercial value of that strategy depends on whether the SMS indication is necessary for meaningful market access and whether other conduct supports induced infringement.

The Hatch-Waxman framework also creates a 30-month stay in certain circumstances after a timely patent-infringement action based on a Paragraph IV notice.[4] The stay is a regulatory timing mechanism, not a determination that the patent is valid or infringed.

Which companies are challenging tasimelteon exclusivity?

The principal commercial exposure is from generic manufacturers that pursue ANDA approval for tasimelteon capsules or other tasimelteon dosage forms. Public FDA and court records, rather than the patent itself, determine whether a particular company has filed an ANDA, submitted a Paragraph IV certification, or entered litigation involving Patent 10,179,119.

No biosimilar pathway applies. Tasimelteon is a small-molecule drug, so competitive entry would proceed through the ANDA pathway rather than through a 351(k) biosimilar application.

The absence of biosimilar risk does not eliminate competition. Generic tasimelteon applicants can challenge the active-ingredient, formulation, method-of-use, and Orange Book patent landscape through separate certifications and litigation.

What litigation and settlement issues matter?

For this patent, the principal litigation questions are:

Whether Patent 10,179,119 is listed for the relevant Hetlioz product and indication
Whether a Paragraph IV notice identifies the patent
Whether Vanda sues within the statutory period
Whether the case produces a 30-month stay
Whether the parties settle before trial
Whether a settlement permits an earlier launch date
Whether the generic label excludes SMS use
Whether the patent survives invalidity and noninfringement defenses

A settlement could establish a launch date before the April 2035 patent expiration while preserving some period of branded market protection. The settlement's value would depend on the remaining orphan exclusivity, the number of competing ANDAs, the scope of the generic label, and the strength of other Hetlioz patents.

How does Patent 10,179,119 compare with other tasimelteon patents?

Patent category	Typical subject matter	Relevance to generic entry
Compound patents	Tasimelteon or related melatonin-receptor ligands	May have earlier expiration and broader chemical scope
Formulation patents	Tablets, liquids, release characteristics, excipients	Can block a particular product design
Method-of-use patents	Non-24, SMS, circadian or sleep disorders	Can block labeled indications
Manufacturing patents	Synthesis, purification, crystallization	Can require process redesign or licensing
Patent 10,179,119	Tasimelteon for SMS sleep disturbances	Directly targets the SMS indication and regimen

Patent 10,179,119 is strategically important because it protects the indication rather than the molecule. A generic company may avoid an expired compound patent yet still face the SMS method claim. Conversely, a generic may enter for a non-SMS indication if it can lawfully omit the patented use and avoid conduct that induces infringement.

What revenue exposure does the patent create?

The patent's revenue exposure is concentrated in the SMS segment rather than the entire Hetlioz franchise. The patent does not independently protect all tasimelteon sales for Non-24-Hour Sleep-Wake Disorder.

The commercial impact depends on:

The number of SMS patients diagnosed and treated
Pediatric and adult labeling
Reimbursement and orphan-drug pricing
The share of Hetlioz revenue attributable to SMS
The number and timing of ANDA approvals
The ability to enforce the patent against an SMS-labeled generic
The presence of other unexpired patents

Because the patent extends beyond likely orphan exclusivity, it can preserve indication-specific protection after the seven-year orphan period ends. It does not guarantee market exclusivity if a competitor enters with a legally adequate carve-out or prevails on invalidity or noninfringement.

Key Takeaways

U.S. Patent 10,179,119 covers tasimelteon treatment of sleep disturbances in patients with Smith-Magenis Syndrome.
Claim 1 is the central claim and requires SMS, sleep disturbances, tasimelteon, once-daily administration, pre-bedtime dosing, and an effective amount.
Claims 5 and 6 cover approximately 5 to 100 mg/day and approximately 20 mg/day, respectively.
Claims 7 through 9 protect pre-bedtime administration, including administration one hour before bedtime.
Claim 10 protects maintenance of treatment effects through ongoing daily dosing.
The patent is a method-of-use patent, not a formulation or manufacturing patent.
Its estimated ordinary expiration is April 11, 2035, subject to USPTO patent-term adjustments or other term modifications.
FDA approval of Hetlioz for SMS created the key commercial indication associated with the patent.
Orphan exclusivity and patent exclusivity are separate rights; orphan exclusivity likely expires substantially earlier than the patent.
Generic competition would likely involve Paragraph IV certifications, potential litigation, a possible 30-month stay, and a labeling carve-out analysis.
No biosimilar pathway applies because tasimelteon is a small molecule.

FAQs About Tasimelteon Patent 10,179,119

Does Patent 10,179,119 cover all uses of Hetlioz?

No. It covers the claimed use of tasimelteon for sleep disturbances in patients with Smith-Magenis Syndrome. It does not expressly cover every use for Non-24-Hour Sleep-Wake Disorder or other sleep conditions.

Can a generic avoid the patent by using a liquid formulation?

Not necessarily. The claims do not require a tablet or any particular formulation. A liquid product could still infringe if it is used or labeled for the claimed SMS regimen.

Does a 20-mg generic dose practice the patent?

It may. A 20-mg once-daily dose falls within claim 6 if the other limitations, including SMS treatment and pre-bedtime administration, are met.

Can a generic launch before 2035?

Potentially. Entry could occur through a successful invalidity or noninfringement challenge, a permitted indication carve-out, a settlement license, or expiration of other regulatory barriers. The patent's estimated term alone does not determine the actual launch date.

Is Patent 10,179,119 relevant to pediatric SMS treatment?

Yes. The patent claims a patient with SMS without imposing an age limitation. FDA's SMS-related tasimelteon approval and labeling determine the regulated patient population, while the patent claims determine the legal scope of the method.[2]

References

United States Patent and Trademark Office. (2019). U.S. Patent No. 10,179,119, methods of treating sleep disorders in patients with Smith-Magenis Syndrome. U.S. Department of Commerce. https://patents.google.com/patent/US10179119B2
U.S. Food and Drug Administration. (2020). Hetlioz (tasimelteon) prescribing information. https://www.accessdata.fda.gov/drugsatfda_docs/label/
U.S. Food and Drug Administration. (2024). Approved drug products with therapeutic equivalence evaluations: Orange Book. https://www.accessdata.fda.gov/scripts/cder/ob/
U.S. Congress. (2023). Federal Food, Drug, and Cosmetic Act, 21 U.S.C. § 355; 35 U.S.C. §§ 271(e), 282. https://uscode.house.gov/

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Patented / Exclusive Use	Submissiondate
Vanda Pharms Inc	HETLIOZ	tasimelteon	CAPSULE;ORAL	205677-001	Jan 31, 2014	AB	RX	Yes	Yes	⤷ Start Trial	⤷ Start Trial				TREATMENT OF NIGHTTIME SLEEP DISTURBANCES IN SMITH-MAGENIS SYNDROME BY ADMINISTERING TASIMELTEON	⤷ Start Trial
Vanda Pharms Inc	HETLIOZ LQ	tasimelteon	SUSPENSION;ORAL	214517-001	Dec 1, 2020		RX	Yes	Yes	⤷ Start Trial	⤷ Start Trial				TREATMENT OF NIGHTTIME SLEEP DISTURBANCES IN SMITH-MAGENIS SYNDROME BY ADMINISTERING TASIMELTEON	⤷ 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

PCT Information
PCT Filed	August 29, 2015	PCT Application Number:	PCT/US2015/047610
PCT Publication Date:	March 10, 2016	PCT Publication Number:	WO2016/036619

Country	Patent Number	Estimated Expiration	Supplementary Protection Certificate	SPC Country	SPC Expiration
Australia	2015312252	⤷ Start Trial
Australia	2020239640	⤷ Start Trial
Brazil	112017003644	⤷ Start Trial
Canada	2957588	⤷ Start Trial
Canada	3124872	⤷ Start Trial
China	106604726	⤷ Start Trial
China	116098887	⤷ Start Trial
>Country	>Patent Number	>Estimated Expiration	>Supplementary Protection Certificate	>SPC Country	>SPC Expiration

Details for Patent: 10,179,119

Which drugs does patent 10,179,119 protect, and when does it expire?

Summary for Patent: 10,179,119