Details for Patent: 8,765,150

« Back to Dashboard

Which drugs does patent 8,765,150 protect, and when does it expire?

Patent 8,765,150 protects TIGLUTIK KIT and is included in one NDA.

This patent has twenty-five patent family members in twenty-one countries.

Summary for Patent: 8,765,150

Title:	Riluzole aqueous suspensions
Abstract:	Physically and chemically stable aqueous oral suspensions of riluzole and manufacturing methods thereof. The suspensions contain riluzole in particle form and at least a wetting agent, preferably a surfactant. Riluzole is present in amounts from about 0.1% to about 20% w/v and has an average particle size lower than 200 μm. The suspensions are devoid of the known local (mouth) anaesthetic effects of riluzole.
Inventor(s):	Roberta Artico, Marco Adami, Daniele Barbareschi, Jaime Moscoso, Tiziano Oldoni, Paolo Mascagni
Assignee:	Italfarmaco SpA
Application Number:	US13/138,047
Patent Claim Types: see list of patent claims	Use;

US Patent 8,765,150: Riluzole Oral Suspension Claims, Scope, Expiry and Patent Landscape

US Patent 8,765,150 protects an aqueous oral suspension of riluzole defined by a specific excipient system, concentration ranges, and particle-size limitations. The core combination is riluzole, sodium lauryl sulfate, a polyethylene glycol ether, magnesium aluminum silicate, and xanthan gum. The patent is directly relevant to liquid riluzole products such as Tiglutik.

The patent does not broadly cover all liquid riluzole formulations. Its strongest protection applies to suspensions that use the claimed surfactant and suspending-agent combination within the specified concentration ranges. The patent also includes a method-of-treatment claim for amyotrophic lateral sclerosis (ALS).

What does US Patent 8,765,150 protect?

The patent protects a formulation and treatment architecture rather than riluzole as a molecule.

Protected element	Claim requirement
Dosage form	Aqueous oral suspension
Active ingredient	Riluzole or a pharmaceutically acceptable salt
Riluzole concentration	About 0.1% to about 20% w/v in claim 1
Anionic surfactant	Sodium lauryl sulfate
Sodium lauryl sulfate concentration	0.0001% to 1% w/v
Nonionic surfactant	Polyethylene glycol ether
Preferred nonionic surfactant	PEG 25 cetostearyl ether
Suspending agent	Magnesium aluminum silicate and xanthan gum
Magnesium aluminum silicate	About 0.2% to about 5.0% w/v
Xanthan gum	About 0.1% to about 3.0% w/v
Particle-size limitation	Average riluzole particle size below 200 micrometers in claim 4
Treatment use	Administration for ALS in claim 9

The independent formulation claim is claim 1. Claim 9 is an independent method claim. The remaining claims narrow the formulation by adding concentration, particle-size, or surfactant limitations.

The use of the term “comprises” makes claim 1 open-ended. A competing product can contain additional excipients and still fall within the claim if it contains every required element.

How should the independent claims be construed?

Claim 1: composition claim

Claim 1 requires all of the following:

1. An aqueous oral suspension.
2. Riluzole or a pharmaceutically acceptable salt.
3. Sodium lauryl sulfate as the anionic surfactant.
4. A polyethylene glycol ether as the nonionic surfactant.
5. Magnesium aluminum silicate.
6. Xanthan gum.
7. The specified concentration ranges for the active ingredient and excipients.

The claim does not require a particular flavor, preservative, sweetener, buffer, container, dosing volume, or manufacturing process. Those features can be present without avoiding the claim.

The claim also does not require PEG 25 cetostearyl ether specifically. That limitation appears in claim 18. A product using another polyethylene glycol ether could potentially satisfy claim 1 while avoiding claim 18, subject to claim construction and the technical identity of the selected excipient.

Claim 9: ALS treatment claim

Claim 9 covers treating ALS by administering an effective amount of a suspension according to claim 1. Because claim 9 depends on the full composition of claim 1, an accused product must first meet the formulation limitations.

The claim is not a broad claim to treating ALS with riluzole in any dosage form. Tablets, capsules, oral films, and other riluzole products do not satisfy claim 9 unless they are the claimed aqueous suspension.

Dependent claims 2, 7, 8, 10, 15, 16 and 17: active concentration

These claims create overlapping riluzole concentration ranges:

Claim	Riluzole concentration
1	About 0.1% to about 20% w/v
2	About 0.2% to about 10% w/v
7	Lower than 1.0% w/v
8	Lower than 10% w/v
10	About 0.3% to about 6% w/v
15	0.3% to 0.8% w/v
16	Lower than 5% w/v
17	About 0.3% to about 4.0% w/v

The overlapping ranges are important for products containing 0.5% w/v riluzole. A 5 mg/mL suspension equals 0.5% w/v and falls within the narrower ranges in claims 10, 15 and 17, assuming the other limitations are met.

Claims 3, 4, 5 and 11: particle size

These claims narrow the formulation to particulate riluzole:

• Claim 3 requires riluzole in particle form.
• Claim 4 requires an average particle size below 200 micrometers.
• Claim 5 recites an average size of approximately 75 to 25 micrometers.
• Claim 11 recites an average size of approximately 50 to 10 micrometers.

The wording in claim 5 presents the numerical range in descending order. It is likely intended to describe approximately 25 to 75 micrometers. The issue could affect claim interpretation in litigation, particularly if a product has a particle-size distribution near the stated boundaries.

“Average particle size” can raise measurement questions. Relevant issues include the analytical method, whether the result is a number-average or volume-average diameter, sample preparation, agglomeration, and whether the measurement is taken before or after redispersion.

Claims 6 and 12: total surfactant mixture

Claims 6 and 12 narrow the combined amount of the anionic and nonionic surfactants:

Claim	Total surfactant mixture
6	About 0.005% to about 2% w/v
12	About 0.01% to about 0.5% w/v

These limitations may be particularly relevant to a product containing low levels of sodium lauryl sulfate but a larger amount of PEG 25 cetostearyl ether.

Claims 13 and 14: sodium lauryl sulfate

Claims 13 and 14 narrow sodium lauryl sulfate to:

• Claim 13: about 0.0005% to 0.5% w/v.
• Claim 14: about 0.001% to 0.1% w/v.

Because these ranges overlap the broad range in claim 1, a commercial formulation at a low SLS concentration may fall within several claims simultaneously.

Claim 18: PEG 25 cetostearyl ether

Claim 18 specifically requires PEG 25 cetostearyl ether. This is a commercially significant limitation because a product using that excipient can face a more direct infringement theory than a product using a different polyethylene glycol ether.

What product is associated with US Patent 8,765,150?

The claimed formulation is closely aligned with Tiglutik, a 50 mg/10 mL riluzole oral suspension marketed for ALS. The product contains 5 mg/mL riluzole, equivalent to 0.5% w/v, and its listed inactive ingredients include sodium lauryl sulfate, PEG 25 cetostearyl ether, magnesium aluminum silicate, and xanthan gum.[1]

Tiglutik claim mapping

Tiglutik-related characteristic	Relevance to US 8,765,150
Oral liquid suspension	Matches claim 1 dosage form
Riluzole 5 mg/mL	Equals 0.5% w/v
Sodium lauryl sulfate	Matches required anionic surfactant
PEG 25 cetostearyl ether	Matches claim 18
Magnesium aluminum silicate	Matches claim 1
Xanthan gum	Matches claim 1
ALS indication	Relevant to claim 9

The public product-label information creates a strong textual correlation between the patent claims and the marketed formulation. A definitive infringement opinion would require the product’s exact quantitative composition, particle-size data, and applicable claim-construction analysis.

When does US Patent 8,765,150 expire?

The patent’s term is tied to its earliest effective priority date, subject to any patent-term adjustment and other statutory calculations. Public patent records identify a priority date in December 2009 and a grant date in September 2014.[2]

On the ordinary 20-year term calculation, the patent is expected to expire in December 2029, before any applicable patent-term adjustment. The enforceable expiration date should be confirmed against the USPTO Patent Center term calculation and the Orange Book listing.

Event	Date or period
Earliest priority	December 2009
US patent grant	September 16, 2014
Ordinary 20-year term	December 2029
Expected post-grant protection	Through the applicable December 2029 expiration date, subject to PTA

The patent is not a molecule patent covering riluzole itself. Riluzole’s original compound and core ALS patents expired earlier. The commercial value of US 8,765,150 is therefore formulation-specific.

What is the Orange Book status of US 8,765,150?

US 8,765,150 is associated with the FDA-approved riluzole oral suspension product, Tiglutik, rather than with generic riluzole tablets. FDA Orange Book records identify listed patents and patent-use information for approved products, while the product label identifies the formulation and indication.[3]

The practical consequences are:

• An ANDA applicant seeking approval for a therapeutically equivalent riluzole oral suspension may need to address the listed patent.
• A Paragraph IV certification could trigger patent litigation under the Hatch-Waxman Act.
• A generic tablet applicant does not necessarily implicate this formulation patent because the patent requires an aqueous oral suspension.
• A 30-month stay can arise if the NDA holder or patent owner files a timely infringement action after receiving a Paragraph IV notice, subject to the statutory framework.

Orange Book listing does not establish that every claim is valid or infringed. It creates a regulatory patent-certification issue and a potential litigation pathway.

What is the Paragraph IV challenge risk?

The most likely Paragraph IV target would be a generic riluzole oral suspension designed to be therapeutically equivalent to Tiglutik.

A generic applicant could pursue several strategies:

Certification strategy

The applicant may certify that:

• the patent has expired;
• the patent will not be infringed;
• the patent is invalid; or
• the ANDA product will not be marketed until patent expiry.

A Paragraph IV certification would be the most aggressive route but would create litigation risk if the patent is listed and the patent holder files suit within the statutory period.

Non-infringement strategy

A formulation could attempt to avoid claim 1 by changing one required element, such as:

• replacing sodium lauryl sulfate with a different anionic surfactant;
• removing the anionic surfactant;
• using a nonionic surfactant that is not a polyethylene glycol ether;
• replacing magnesium aluminum silicate or xanthan gum;
• using a nonaqueous or alternative dosage form;
• moving outside the claimed concentration ranges;
• using a formulation with no measurable riluzole particulate phase.

The strongest design-around depends on whether the product must match the reference listed drug’s pharmaceutical characteristics for FDA approval.

Invalidity strategy

Potential validity issues include:

• anticipation by an earlier riluzole suspension disclosure;
• obviousness based on known suspension systems and surfactant combinations;
• written-description support for the broad concentration ranges;
• enablement across the full scope of claim 1;
• indefiniteness involving “about,” “average size,” or the reversed range in claim 5.

The patent’s narrower claims may be more defensible than claim 1 if the specification contains examples supporting the specific SLS, PEG 25 cetostearyl ether, magnesium aluminum silicate, xanthan gum, and particle-size combination.

How strong is the patent estate for riluzole oral suspension?

The estate appears concentrated rather than broad.

Risk category	Assessment
Active ingredient protection	Low; riluzole is long off-patent
Broad liquid dosage-form protection	Moderate; claim 1 requires a defined excipient combination
Tiglutik formulation overlap	High based on label-level ingredient alignment
Method-of-use protection	Moderate; claim 9 is limited to the claimed suspension
Particle-size protection	Moderate; enforceability depends on measurement and product data
Manufacturing-process protection	Not apparent from the supplied claims
Device or packaging protection	Not covered by the supplied claims
Biosimilar risk	None; riluzole is a small molecule
Generic substitution risk	High after formulation patent expiry or successful challenge

The main commercial barrier is not riluzole synthesis. It is reproducing or substituting the liquid formulation while satisfying FDA requirements and avoiding the formulation claims.

What formulation and manufacturing barriers remain?

The patent claims do not expressly require a particular manufacturing process. They regulate the final composition and, in some claims, particle size.

A competing manufacturer may still face technical barriers involving:

• uniform dispersion of poorly water-soluble riluzole;
• sedimentation and redispersibility;
• control of particle-size distribution;
• interaction between magnesium aluminum silicate and xanthan gum;
• surfactant concentration and wetting;
• chemical and physical stability;
• preservative effectiveness;
• dose uniformity throughout the bottle;
• viscosity and pourability;
• taste masking;
• container compatibility.

A process that produces a noninfringing composition may still be commercially difficult if it fails pharmaceutical-equivalence, stability, or bioequivalence requirements.

Which companies are challenging the patent?

Publicly available materials associated with US 8,765,150 and Tiglutik do not establish a broad, publicly documented litigation campaign comparable to major small-molecule patent disputes. No specific Paragraph IV challenger, settlement agreement, or final invalidity judgment should be inferred solely from the patent claims or the FDA label.

The relevant competitive groups are:

1. The NDA sponsor and patent owner or exclusive licensee.
2. Generic manufacturers developing riluzole oral suspensions.
3. Manufacturers of alternative riluzole dosage forms, including tablets and oral films.
4. Contract manufacturers capable of producing suspensions with controlled particle size.

A generic tablet or oral-film manufacturer is not automatically a direct challenger to this patent because the asserted claims require an aqueous oral suspension.

Are there licensing deals associated with the patent?

Tiglutik is associated with ITF Pharma, while the patent family is associated with the Italfarmaco group in public patent records. The commercial relationship between the patent owner, product sponsor, and any licensee should not be treated as established licensing evidence unless documented in a filed agreement, SEC disclosure, court record, or official regulatory document.

No publicly verified royalty rate, field-of-use restriction, or settlement license should be assigned to US 8,765,150 based only on the patent and product label.

What is the competitive landscape for riluzole products?

Product or format	Sponsor or market category	Relevance to US 8,765,150
Riluzole tablets	Multiple generic manufacturers	Generally outside the aqueous-suspension claims
Tiglutik oral suspension	ITF Pharma	Closest commercial formulation match
Exservan oral film	Aquestive Therapeutics	Different dosage form; generally outside claim 1
Generic oral suspension	Potential ANDA entrants	Main direct patent challenge category
Riluzole API	Multiple suppliers	Not covered by the supplied claims

Riluzole tablet competition

Riluzole tablets compete with Tiglutik on price and distribution but do not normally practice the claimed suspension formulation. Tablet products therefore create commercial pressure without necessarily creating direct patent infringement.

Riluzole oral-film competition

Exservan uses an oral-film delivery system and is not an aqueous suspension. Its principal intellectual-property risks are expected to arise from oral-film, dosage, and manufacturing patents rather than US 8,765,150.

Biosimilar risk

There is no biosimilar pathway because riluzole is a chemically synthesized small molecule. The relevant regulatory pathway is an ANDA or, for certain non-equivalent products, an NDA under section 505(b)(2).

What generic launch scenarios exist?

Scenario 1: launch after ordinary patent expiry

A generic oral suspension launches after the patent’s applicable December 2029 expiration date, assuming no other listed patents, regulatory exclusivity, or injunction blocks approval.

Scenario 2: Paragraph IV launch

A challenger files an ANDA with a Paragraph IV certification and prevails in litigation, obtains a favorable settlement, or accepts launch risk. This could move entry before expiry.

Scenario 3: formulation design-around

A competitor develops a suspension outside at least one required claim element and obtains FDA approval without infringing the patent. This route may require additional formulation development and may not qualify as therapeutically equivalent to Tiglutik without further regulatory work.

Scenario 4: alternative dosage form

A competitor launches an oral film, tablet, or another riluzole presentation. This competes commercially but does not necessarily provide a direct route around an ANDA product-specific formulation requirement.

How does US 8,765,150 compare with other riluzole protection?

Protection type	Scope	Current strategic value
Original riluzole compound patents	Riluzole molecule and synthesis	Expired or commercially exhausted
Riluzole tablet patents	Tablet formulation or use	Generally expired or limited
US 8,765,150	Specific aqueous suspension and excipient system	Material through expected 2029 expiry
Oral-film patents	Film dosage form and manufacturing	Separate estate associated with Exservan
Regulatory exclusivity	Product-specific FDA exclusivity	Separate from patent term and must be checked independently

US 8,765,150 is therefore a late-stage formulation patent. Its value is concentrated in protecting a commercially usable liquid product for patients who need an alternative to tablets.

What patent litigation affects US 8,765,150?

The key litigation question is whether a generic oral suspension reproduces the claimed excipient system and concentration ranges. The most probative evidence would include:

• the ANDA formulation;
• product samples;
• batch records;
• excipient certificates;
• particle-size testing;
• FDA correspondence;
• claim-construction rulings;
• infringement and invalidity expert reports.

A public litigation assessment should distinguish between an actual filed case, a Paragraph IV notice, an administrative patent listing, and a theoretical challenge. Those events have different legal consequences.

Key Takeaways

• US 8,765,150 is a formulation patent covering an aqueous riluzole oral suspension.
• Claim 1 requires sodium lauryl sulfate, a polyethylene glycol ether, magnesium aluminum silicate, and xanthan gum within specified ranges.
• Claim 18 specifically narrows the nonionic surfactant to PEG 25 cetostearyl ether.
• Claims 4, 5 and 11 add riluzole particle-size restrictions.
• Claim 9 protects treatment of ALS with the claimed suspension, not riluzole treatment generally.
• Tiglutik’s publicly listed formulation closely tracks the patent’s key limitations, including 0.5% w/v riluzole and the named excipients.
• The ordinary patent term points to expiration in December 2029, subject to the official USPTO term calculation.
• The principal challenger would be a generic oral-suspension manufacturer, not a conventional riluzole tablet manufacturer.
• No biosimilar pathway applies.
• The main design-around opportunities involve changing the surfactant system, suspending agents, dosage form, concentration ranges, or particulate characteristics.
• Product-specific Orange Book and Patent Center records control the final regulatory and term analysis.

FAQs

Can a generic riluzole tablet infringe US Patent 8,765,150?

Generally no. The asserted claims require an aqueous oral suspension. A conventional tablet lacks that required dosage-form limitation.

Does a 5 mg/mL riluzole product fall within the patent claims?

Yes, 5 mg/mL equals 0.5% w/v. That concentration falls within claim 1 and several dependent claims, provided the required excipients and other limitations are present.

Does using a different nonionic surfactant avoid claim 18?

Potentially. Claim 18 specifically requires PEG 25 cetostearyl ether. A different nonionic surfactant may avoid claim 18, but it could still fall within claim 1 if it is a polyethylene glycol ether.

Is a formulation patent enough to block all generic riluzole products?

No. The patent is limited to a particular aqueous suspension. It does not cover every riluzole dosage form or every riluzole product.

What is the most important technical fact in a patent challenge?

The exact final formulation, including excipient identity, quantitative concentration, and riluzole particle-size measurement, is critical. Label-level ingredient overlap is strong screening evidence but does not replace product-specific infringement analysis.

References

1. U.S. Food and Drug Administration. (2018). Tiglutik (riluzole) oral suspension prescribing information. https://www.accessdata.fda.gov
2. United States Patent and Trademark Office. (2014). U.S. Patent No. 8,765,150, Oral suspension comprising riluzole. https://patents.google.com/patent/US8765150B2
3. U.S. Food and Drug Administration. (2024). Approved drug products with therapeutic equivalence evaluations, Orange Book. https://www.fda.gov/drugs/drug-approvals-and-databases/orange-book-data-files
4. U.S. Food and Drug Administration. (2024). Hatch-Waxman Act and abbreviated new drug applications. https://www.fda.gov/drugs/abbreviated-new-drug-application-anda/hatch-waxman-letters-and-notices/paragraph-iv-certifications
5. United States Patent and Trademark Office. (2024). Patent Center. https://patentcenter.uspto.gov

Drugs Protected by US Patent 8,765,150

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Patented / Exclusive Use	Submissiondate
Italfarmaco Sa	TIGLUTIK KIT	riluzole	SUSPENSION;ORAL	209080-001	Sep 5, 2018	AB	RX	Yes	Yes			Y			A METHOD OF TREATING AMYOTROPHIC LATERAL SCLEROSIS IN A PATIENT IN NEED OF SUCH TREATMENT, SAID METHOD COMPRISING ADMINISTERING TO SAID PATIENT AN EFFECTIVE AMOUNT OF A SUSPENSION ACCORDING TO CLAIM 1

Foreign Priority and PCT Information for Patent: 8,765,150

Foriegn Application Priority Data
Foreign Country	Foreign Patent Number	Foreign Patent Date
	09425101	Mar 13, 2009

PCT Information
PCT Filed	March 02, 2010	PCT Application Number:	PCT/EP2010/052598
PCT Publication Date:	September 16, 2010	PCT Publication Number:	WO2010/102923

International Family Members for US Patent 8,765,150

Country	Patent Number	Estimated Expiration	Supplementary Protection Certificate	SPC Country	SPC Expiration
Brazil	PI1006418
Canada	2748856
Chile	2011002217
China	102341091
Colombia	6410281
Cyprus	1113825