United States Patent 12,115,145: Scope, Claims, Exclusivity, and Oxybate Patent Landscape

U.S. Patent No. 12,115,145 protects an orally administered, once-nightly gamma-hydroxybutyrate formulation for narcolepsy that combines an immediate-release portion with a modified-release portion. The independent claim is directed to the dosage-form architecture and excipient combination, rather than to gamma-hydroxybutyrate as a molecule or to narcolepsy treatment generally. The patent is most relevant to once-nightly extended-release sodium oxybate products, including Avadel Pharmaceuticals' Lumryz.

The strongest infringement risk arises where a competing product has all of the following characteristics: sodium oxybate or another gamma-hydroxybutyrate source, both immediate- and modified-release fractions, immediate-release povidone and microcrystalline cellulose, and a single oral administration at bedtime.

What does U.S. Patent 12,115,145 cover?

The patent covers a multipart pharmaceutical formulation in which gamma-hydroxybutyrate is delivered through two release phases:

Required feature	Scope under claim 1
Therapeutic use	Treatment of narcolepsy or a narcolepsy symptom
Route	Oral administration
Dosing frequency	Once nightly
Active ingredient	Gamma-hydroxybutyrate
Immediate-release fraction	Contains gamma-hydroxybutyrate, povidone, and microcrystalline cellulose
Modified-release fraction	Contains gamma-hydroxybutyrate
Product architecture	Immediate-release plus modified-release portions

Claim 1 is an apparatus-like formulation claim. It does not require a particular tablet shape, capsule, granule size, manufacturing process, dissolution profile, or specific modified-release mechanism on its face. The claim does require two distinct release portions and requires gamma-hydroxybutyrate in each portion.

The claim language creates several potentially important construction issues:

Whether the product must contain physically separate populations of immediate-release and modified-release particles.
Whether a single matrix with different release zones qualifies as two portions.
Whether “once nightly” is a structural limitation, a labeled-use limitation, or both.
Whether gamma-hydroxybutyrate includes sodium oxybate and other pharmaceutically acceptable salts.
Whether povidone and microcrystalline cellulose must be present in the immediate-release portion specifically, rather than elsewhere in the dosage form.

For a generic or follow-on product, the location of each excipient may be as important as its presence in the overall product.

How do the dependent claims narrow the patent scope?

Claims 2 through 29 add active-ingredient ranges, excipient concentrations, acidifiers, suspending agents, and modified-release polymers. They are fallback positions if a court narrows or invalidates claim 1.

Active-ingredient and immediate-release limitations

Claim 2 covers a total gamma-hydroxybutyrate amount equivalent to 3.0 g to 12 g of sodium oxybate. This range encompasses common therapeutic dose levels for sodium oxybate products.

Claim 21 adds an immediate-release portion containing 81% sodium oxybate by weight. Claim 22 specifies 15% microcrystalline cellulose in the immediate-release portion.

These claims may be difficult to apply where a competing product uses a different active concentration, but concentration alone may not avoid claim 1 if the competitor still satisfies the broader formulation architecture.

Immediate-release excipient limitations

Claims 3 and 4 specify:

3.33% povidone by weight; and
11.75% microcrystalline cellulose by weight.

These percentages appear directed to a specific immediate-release formulation implementation. Claim 3 and claim 4 are narrower than claim 1 because claim 1 requires the excipients but does not specify their concentrations.

Modified-release excipient limitations

Claim 5 requires hydrogenated vegetable oil, and claim 6 narrows that limitation to 10.07% by weight.

Claim 28 requires the modified-release portion to contain:

povidone;
microcrystalline cellulose;
hydrogenated vegetable oil;
methacrylic acid copolymer type C; and
methacrylic acid copolymer type B.

Claim 29 uses functional chemical language and requires:

povidone;
microcrystalline cellulose;
a polymer carrying free carboxylic groups; and
a hydrophobic compound with a melting point of at least 40°C.

Claims 28 and 29 are important for formulation comparison because they reach beyond a specific commercial excipient name. A product using a different polymer trade name may still fall within claim 29 if the polymer has free carboxylic groups.

Acidifying agents and viscosity modifiers

Claims 7 through 13 address an acidifying agent. The concentration ranges progressively narrow:

Claim	Acidifying-agent range
8	1.2% to 15%
9	1.2% to 10%
10	1.2% to 5%
11	1.6% to 3.2%
12	Malic acid
13	1.58% malic acid

Claims 14 through 20 cover alternative or additional viscosity and suspending systems:

Claim	Limitation
14	Carrageenan gum
15	1.05% carrageenan gum
16	Hydroxyethyl cellulose
17	1.05% hydroxyethyl cellulose
18	Carrageenan and hydroxyethyl cellulose in equal amounts
19	Xanthan gum
20	0.70% xanthan gum

Claims 23 through 27 cover one or more suspending or viscosifying agents, with the broadest stated range of 1% to 15% and narrower ranges down to 2% to 3%.

These claims create a broad genus around viscosity-control systems while also protecting specific formulations. A design-around that changes the identity of the thickener may avoid claims 14 through 20 but may still implicate claims 23 through 27.

What is the likely commercial product associated with Patent 12,115,145?

The claim structure corresponds closely to the technology used in Lumryz, an extended-release sodium oxybate product approved by the FDA for once-nightly treatment of cataplexy or excessive daytime sleepiness in adults with narcolepsy. Lumryz uses a single bedtime dose rather than the multiple nighttime doses associated with immediate-release sodium oxybate products. The FDA approved Lumryz under NDA 214755 in May 2023.[1]

Product	Active ingredient	Release profile	Typical nighttime administration	FDA status
Lumryz	Sodium oxybate	Extended release	Once nightly	Approved
Xyrem	Sodium oxybate	Immediate release	Divided nighttime dosing	Approved
Xywav	Calcium, magnesium, potassium, and sodium oxybates	Immediate release	Divided nighttime dosing	Approved

The commercial value of the patent is tied to the once-nightly delivery profile. A competitor that uses immediate-release oxybate and requires multiple doses would not ordinarily satisfy the once-nightly limitation, although it could compete commercially without practicing the claimed architecture.

What patents protect Lumryz and once-nightly sodium oxybate?

Patent 12,115,145 should be analyzed as one member of a broader Avadel oxybate patent family and Orange Book strategy. The relevant estate may include patents directed to:

multipart immediate-release and modified-release formulations;
excipient combinations;
dissolution and release characteristics;
methods of treating narcolepsy;
once-nightly dosing;
manufacturing processes;
specific formulation compositions.

The existence of a patent family matters because avoiding one patent does not necessarily eliminate all U.S. patent risk. A product may avoid a formulation claim while still implicating a method-of-use patent or another listed patent covering the same commercial product.

The principal technical distinction from Xyrem and Xywav is the release system. Xyrem and Xywav rely on immediate-release oxybate formulations that are administered in divided doses. Patent 12,115,145 instead requires both immediate and modified release in one oral dosage form.

What is the Orange Book status of U.S. Patent 12,115,145?

The FDA Orange Book is the controlling source for determining whether a patent is listed against an approved drug product and whether the patent is identified as covering the drug substance, drug product, or method of use.[2]

For an approved sodium oxybate product, a listed formulation patent can support a Paragraph IV certification by an ANDA applicant. If the applicant asserts that the patent is invalid, unenforceable, or not infringed, the applicant must provide the patent holder with a Paragraph IV notice.

The practical Orange Book questions are:

Whether Patent 12,115,145 is listed against Lumryz;
Whether it is listed as a drug-product or formulation patent;
Whether the listing carries an expiration date later than other Lumryz patents;
Whether the approved product has pediatric exclusivity or patent-term adjustment;
Whether later-issued continuation patents are also listed.

The patent number alone does not establish an Orange Book listing. Patent listing, patent expiration, and regulatory exclusivity are separate legal events. The FDA Orange Book should be reviewed together with the patent file and the approved NDA record.

When does Patent 12,115,145 lose exclusivity?

The statutory patent term generally runs 20 years from the earliest effective nonprovisional filing date, subject to patent-term adjustment, patent-term extension, terminal disclaimers, and priority claims.[3] The operative expiration date should therefore be taken from the issued patent, USPTO Patent Center, and the FDA Orange Book where the patent is listed.

The patent does not provide regulatory exclusivity by itself. Lumryz also received FDA regulatory exclusivity associated with its approval, but that period is distinct from patent protection. A generic applicant may be blocked by regulatory exclusivity even after a patent challenge is available, and a patent may continue after regulatory exclusivity expires.

The key timing sequence is:

Event	Legal significance
FDA approval	Establishes the approved reference product
Patent listing	Identifies patents that may be addressed in an ANDA
Paragraph IV filing	Creates potential patent litigation
30-month stay	May delay ANDA approval if timely litigation is filed
Patent expiration	Removes the patent-based injunction risk for that patent
Regulatory exclusivity expiration	Removes a separate FDA approval barrier

What Paragraph IV challenges could target this patent?

A Paragraph IV challenger would likely attack both infringement and validity.

Noninfringement positions

A competing product could argue that it does not meet one or more required limitations by:

using only immediate-release or only modified-release oxybate;
administering the product more than once nightly;
placing povidone or microcrystalline cellulose outside the immediate-release portion;
using a different binder and filler system;
using a single homogeneous matrix rather than identifiable release portions;
using a non-oxybatelike gamma-hydroxybutyrate source;
selecting a total dose outside the claimed range of claim 2;
omitting acidifying or viscosifying agents recited in dependent claims.

The “once nightly” limitation may be particularly significant. Label language, dosing instructions, physician-use restrictions, and product design would likely be examined together.

Validity positions

Potential validity theories include:

anticipation by an earlier multipart oxybate formulation;
obviousness based on immediate-release sodium oxybate combined with known modified-release technologies;
lack of written description for the breadth of the excipient and polymer classes;
lack of enablement across the full range of release systems;
indefiniteness concerning “once nightly,” “modified release,” or the identity of the two portions;
double patenting if the claims overlap earlier Avadel patents without a valid terminal disclaimer.

The patent's strongest validity position is likely in the narrow formulation combinations and concentration-specific claims. Its broader claim 1 may face greater prior-art and claim-construction pressure because it covers a general combination of immediate and modified release with common pharmaceutical excipients.

How strong is the patent estate?

Patent strength is best assessed by claim specificity, technical differentiation, regulatory relevance, and design-around difficulty.

Factor	Assessment
Product relevance	High for once-nightly extended-release oxybate
Chemical composition protection	Limited; the patent does not broadly claim GHB itself
Formulation protection	High; claim 1 requires a defined two-phase product
Excipient protection	Moderate to high in the dependent claims
Method-of-use protection	Not the principal focus of the supplied claims
Design-around potential	Moderate
Generic litigation exposure	High if a generic seeks a once-nightly extended-release product
Biosimilar relevance	None; sodium oxybate is a small molecule

The patent is stronger against a close copy of the commercial formulation than against a fundamentally different extended-release design. A competitor that develops a once-nightly product using a different release architecture may avoid literal infringement, but it could encounter other patents in the same portfolio or face a doctrine-of-equivalents dispute.

Which companies may challenge once-nightly sodium oxybate?

The likely challenger group consists of generic pharmaceutical companies with ANDA capabilities in controlled substances and modified-release oral dosage forms. Potential entrants would need to address:

FDA controlled-substance requirements;
oxybate abuse and diversion controls;
formulation equivalence;
release-profile equivalence;
REMS or risk-management obligations;
Orange Book patent certifications;
supply and manufacturing controls.

No biosimilar pathway applies. Sodium oxybate is a chemically defined small molecule, so a competitor would use the ANDA pathway rather than the abbreviated pathway for biosimilars under the Public Health Service Act.

Publicly confirmed Paragraph IV litigation, settlements, licenses, and final judgments should be attributed to a specific ANDA, patent, and docket. The supplied claim text does not establish any particular challenger or settlement agreement.

What manufacturing and IP barriers affect generic entry?

A generic must reproduce the relevant pharmacokinetic and release behavior while avoiding the patented formulation combination. The main technical barriers are:

Maintaining a reproducible separation between immediate- and modified-release fractions.
Controlling high-load sodium oxybate processing.
Achieving acceptable dissolution across the full dosing range.
Managing moisture sensitivity, flow, compression, and coating behavior.
Demonstrating bioequivalence for a complex release profile.
Complying with controlled-substance manufacturing and distribution requirements.

Claims 28 and 29 increase the importance of polymer selection and coating chemistry. A manufacturer may avoid a named methacrylic acid copolymer but still encounter the broader functional language in claim 29.

What generic launch scenarios exist?

Scenario 1: Close-copy ANDA

A generic reproduces the same two-phase architecture and key excipients. This creates the highest Paragraph IV and preliminary-injunction risk.

Scenario 2: Alternative once-nightly formulation

A competitor uses a different matrix, coating, osmotic system, multiparticulate platform, or release-controlling polymer. Risk shifts from literal infringement of claim 1 toward other family patents and equivalents.

Scenario 3: Divided-dose oxybate

A product remains immediate release and requires multiple nighttime doses. It competes with Lumryz but is less likely to meet claim 1.

Scenario 4: Reformulated oxybate salt

A different oxybate salt or combination may raise claim-construction questions concerning “gamma-hydroxybutyrate,” but changing the counterion does not automatically avoid every claim.

Key Takeaways

U.S. Patent 12,115,145 is a formulation patent focused on once-nightly oral gamma-hydroxybutyrate delivery.
Claim 1 requires both immediate-release and modified-release portions.
The immediate-release portion must contain gamma-hydroxybutyrate, povidone, and microcrystalline cellulose.
Dependent claims protect specific concentrations of povidone, microcrystalline cellulose, hydrogenated vegetable oil, malic acid, carrageenan, hydroxyethyl cellulose, and xanthan gum.
Claims 28 and 29 target modified-release polymer and hydrophobic-compound systems.
The patent does not broadly claim sodium oxybate as a chemical compound.
The main commercial relevance is Lumryz and competing once-nightly extended-release oxybate products.
Generic risk depends heavily on whether a challenger adopts the same two-phase architecture and excipient allocation.
Biosimilar risk is not applicable because sodium oxybate is a small-molecule drug.
Orange Book listing, patent expiration, Paragraph IV activity, and settlement status must be assessed at the specific NDA, patent-family, and ANDA levels.

Frequently Asked Questions

Does Patent 12,115,145 cover Xyrem?

Not on the supplied claim language if Xyrem is used as an immediate-release, divided-dose product. Xyrem would not ordinarily satisfy the once-nightly and modified-release limitations of claim 1.

Does the patent cover Xywav?

The answer depends on whether the product contains gamma-hydroxybutyrate in both immediate- and modified-release portions and is administered once nightly. A conventional divided-dose immediate-release Xywav regimen would not satisfy the supplied claim elements.

Can a generic avoid the patent by removing povidone?

Removing povidone from the immediate-release portion could avoid literal infringement of claim 1, but the generic would still need to assess other patents and whether a substitute excipient is equivalent under the doctrine of equivalents.

Is claim 1 limited to tablets?

No. The supplied claim does not expressly limit the dosage form to tablets. Capsules, multiparticulates, granules, or other oral dosage forms could fall within the claim if they satisfy all structural and dosing limitations.

Does FDA approval establish infringement?

No. FDA approval concerns safety, efficacy, quality, and regulatory standards. Patent infringement is determined under patent law by comparing the accused product and its labeled use with the properly construed claims.

References

U.S. Food and Drug Administration. (2023). FDA approves new drug for adults with narcolepsy.
U.S. Food and Drug Administration. (n.d.). Approved drug products with therapeutic equivalence evaluations: Orange Book.
United States Patent and Trademark Office. (n.d.). Patent term adjustment and patent term extension guidance.
United States Patent and Trademark Office. (2024). U.S. Patent No. 12,115,145.

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Patented / Exclusive Use	Submissiondate
Alkermes Inc	LUMRYZ	sodium oxybate	FOR SUSPENSION, EXTENDED RELEASE;ORAL	214755-001	May 1, 2023		RX	Yes	Yes	12,115,145	⤷ Start Trial	Y				⤷ Start Trial
Alkermes Inc	LUMRYZ	sodium oxybate	FOR SUSPENSION, EXTENDED RELEASE;ORAL	214755-002	May 1, 2023		RX	Yes	No	12,115,145	⤷ Start Trial	Y				⤷ Start Trial
Alkermes Inc	LUMRYZ	sodium oxybate	FOR SUSPENSION, EXTENDED RELEASE;ORAL	214755-003	May 1, 2023		RX	Yes	No	12,115,145	⤷ Start Trial	Y				⤷ 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

Country	Patent Number	Estimated Expiration	Supplementary Protection Certificate	SPC Country	SPC Expiration
Argentina	109376	⤷ Start Trial
Australia	2017300845	⤷ Start Trial
Australia	2020231916	⤷ Start Trial
>Country	>Patent Number	>Estimated Expiration	>Supplementary Protection Certificate	>SPC Country	>SPC Expiration

Details for Patent: 12,115,145

Which drugs does patent 12,115,145 protect, and when does it expire?

Summary for Patent: 12,115,145