United States Patent 7,262,219: Scope, Claims, Expiration, and Sodium Oxybate Patent Landscape

U.S. Patent No. 7,262,219 protected preservative-free, aqueous sodium gamma-hydroxybutyrate, or sodium oxybate, solutions at high concentration and controlled near-neutral pH. Its principal commercial relevance was the formulation used in Xyrem oral solution. The patent covered composition characteristics, not a particular therapeutic indication, dosing schedule, manufacturing process, delivery device, or patient population.

The patent issued on August 28, 2007, to Orphan Medical, Inc., later acquired by Jazz Pharmaceuticals. Its ordinary patent term ended in December 2022, with pediatric exclusivity extending the regulatory protection period into 2023 according to the Orange Book listing for Xyrem. The patent is therefore no longer an active U.S. patent barrier to generic sodium oxybate formulation claims.[1][2]

What does U.S. Patent 7,262,219 protect?

The patent protects an aqueous pharmaceutical composition containing:

Sodium gamma-hydroxybutyrate at approximately 350 to 750 mg/mL;
A pH-adjusting acid;
A pH of approximately 6.0 to 7.5;
Chemical stability;
Resistance to microbial growth; and
No preservatives.

Claim 1 covers eight organic acids as the pH-adjusting agent:

Malic acid;
Citric acid;
Acetic acid;
Lactic acid;
Carbonic acid;
Formic acid;
Propionic acid; or
Tartaric acid.

Claim 2 narrows the sodium oxybate concentration to approximately 400 to 650 mg/mL. Claim 3 narrows claim 1 to malic acid. Claim 4 is an independent composition claim covering the same concentration, pH, stability, microbial-resistance, and preservative-free limitations, but with one of five inorganic acids:

Hydrochloric acid;
Phosphoric acid;
Sulfuric acid;
Boric acid; or
Nitric acid.

The patent therefore has two independent claim groups: claim 1 for specified organic acids and claim 4 for specified inorganic acids.

How should the claim language be interpreted?

“Consisting essentially of”

“Consisting essentially of” is a transitional phrase between “comprising” and “consisting of.” It generally permits additional ingredients if they do not materially alter the basic and novel characteristics of the claimed composition.

For this patent, the relevant characteristics likely include:

High-concentration aqueous sodium oxybate;
Near-neutral pH;
Chemical stability;
Resistance to microbial growth; and
A preservative-free formulation.

An excipient could therefore be permitted if it does not materially affect those characteristics. A conventional preservative would create a direct problem because the claims expressly require that the composition be free of preservatives. An excipient that functions as an antimicrobial preservative could also create an infringement issue even if it is labeled as another type of ingredient.

“About” concentration and pH ranges

The claims use “about” for both sodium oxybate concentration and pH. A formulation slightly outside 350 to 750 mg/mL or pH 6.0 to 7.5 could still fall within the claim depending on the specification, prosecution history, analytical variability, and the scope of any court construction.

The concentration ranges are significant:

Claim	Sodium oxybate concentration	pH	Acid category
1	About 350-750 mg/mL	About 6.0-7.5	Listed organic acids
2	About 400-650 mg/mL	About 6.0-7.5	Same as claim 1
3	About 350-750 mg/mL	About 6.0-7.5	Malic acid only
4	About 350-750 mg/mL	About 6.0-7.5	Listed inorganic acids

Claim 2 is narrower than claim 1. It does not create a separate acid list. It inherits claim 1’s organic-acid limitations and adds the narrower 400 to 650 mg/mL concentration range.

“Free of preservatives”

The preservative-free limitation is central to the patent. A product containing benzyl alcohol, parabens, sorbic acid used as a preservative, benzoic acid used as a preservative, or another recognized preservative would not literally satisfy the claim.

The analysis depends on function and formulation context. The claims do not prohibit every compound with antimicrobial properties. They require a composition free of preservatives, while separately requiring resistance to microbial growth. A pH-adjusting acid that contributes to microbial resistance does not necessarily become a “preservative” merely because it has antimicrobial activity.

What formulations are protected by U.S. Patent 7,262,219?

The strongest literal infringement case would involve a product that has all of the following characteristics:

An aqueous solution;
Sodium oxybate as the active salt;
Approximately 350 to 750 mg/mL sodium oxybate;
A listed acid as the pH-adjusting agent;
pH of approximately 6.0 to 7.5;
Chemical stability;
Resistance to microbial growth; and
No preservatives.

A formulation containing 400 to 650 mg/mL sodium oxybate and malic acid would implicate claims 1, 2, and 3 if the remaining limitations were satisfied. A formulation using hydrochloric acid would implicate claim 4, but not claims 1 through 3 because hydrochloric acid is in claim 4’s separate acid group.

Formulations outside the literal claim scope

Potential design-around strategies include:

Using a sodium oxybate concentration below approximately 350 mg/mL or above approximately 750 mg/mL;
Using a pH materially below 6.0 or above 7.5;
Selecting a pH-adjusting agent not listed in the claims;
Using a different oxybate salt or counterion;
Including a preservative;
Formulating the product as a nonaqueous dosage form;
Using a solid, powder, tablet, sachet, or other dosage form rather than an aqueous solution; or
Using a different formulation system that does not satisfy the stability and microbial-resistance limitations.

These approaches would require a separate analysis under the doctrine of equivalents. A change that performs substantially the same function in substantially the same way may remain litigable even if it avoids a literal element. The prosecution history and any prior litigation would control the scope of that risk.

Does the patent cover sodium oxybate methods of use or manufacturing processes?

No. The asserted claims supplied for U.S. Patent 7,262,219 are composition claims.

The patent does not directly claim:

Treatment of narcolepsy;
Cataplexy treatment;
Excessive daytime sleepiness treatment;
A dosing schedule;
A restricted-distribution program;
A manufacturing process for sodium oxybate;
A container or dispensing device;
A titration regimen; or
A specific patient population.

A generic product could avoid this patent while still confronting separate method-of-use, formulation, manufacturing, or device patents associated with Xyrem or other sodium oxybate products.

When did U.S. Patent 7,262,219 lose exclusivity?

Patent expiration

The patent’s listed expiration date was December 17, 2022. Xyrem’s Orange Book record reflected pediatric exclusivity extending the applicable regulatory protection period into June 2023.[2][3]

Event	Date
Patent issued	August 28, 2007
Listed patent expiration	December 17, 2022
Pediatric-exclusivity extension associated with Xyrem	Into June 2023
Current status for new U.S. products	Expired; no prospective patent exclusion

Patent expiration eliminates the enforceable exclusionary right under the patent. It does not invalidate other patents in the Xyrem estate, nor does it eliminate regulatory requirements applicable to an ANDA or 505(b)(2) applicant.

What was the Orange Book status of U.S. Patent 7,262,219?

The patent was listed in the FDA Orange Book for Xyrem, an oral solution containing sodium oxybate. The listing identified a formulation patent rather than a method-of-use patent.[2]

The Orange Book listing mattered because an ANDA applicant referencing Xyrem had to address the listed patent through one of the statutory certification pathways:

Paragraph I: No patent information was submitted;
Paragraph II: The patent had expired;
Paragraph III: The applicant would wait until patent expiration; or
Paragraph IV: The patent was invalid, unenforceable, or would not be infringed.

After expiration, the patent no longer creates a Paragraph III launch delay. A later applicant may still need to certify against other unexpired listed patents.

Which companies challenged Xyrem and related sodium oxybate patents?

Generic-drug companies challenged various Xyrem patents through ANDA litigation and Paragraph IV certifications. Publicly reported Xyrem disputes involved companies including Roxane Laboratories, Amneal Pharmaceuticals, Hikma Pharmaceuticals, and other ANDA sponsors at different stages of the product’s patent history.[4][5]

The litigation did not concern only U.S. Patent 7,262,219. Jazz’s commercial protection strategy relied on a broader patent estate that included later formulation, concentration, dosing, distribution, and method-of-use patents. The legal outcome for any particular generic depended on the patents asserted against that defendant, the product formulation, the proposed label, and settlement terms.

A Paragraph IV notice against the ’219 patent would have triggered potential Hatch-Waxman litigation. A suit filed within 45 days could have generated a 30-month ANDA approval stay, subject to statutory exceptions and the patent’s remaining term. Because the ’219 patent expired in 2022, that mechanism no longer creates a current approval barrier based on this patent.

How strong was the patent estate for Xyrem?

The ’219 patent was commercially important but technically narrow relative to the full Xyrem estate.

Strengths

It covered the high-concentration aqueous formulation associated with Xyrem.
It used multiple acid alternatives.
It included both organic and inorganic acid claim sets.
Claim 2 provided a narrower concentration range that could support a preferred commercial embodiment.
Claim 3 singled out malic acid, creating a focused dependent claim.

Limitations

The patent did not cover sodium oxybate generally.
It did not cover every aqueous concentration.
It did not cover every pH-adjusting agent.
It did not cover methods of treating narcolepsy.
It did not cover manufacturing methods.
It did not cover solid or alternative dosage forms.
The microbial-resistance and stability limitations could require technical proof.
The patent expired before the later generation of sodium oxybate products reached broad commercial competition.

The patent was therefore strongest against a close formulation copy of Xyrem and weaker against products using materially different concentrations, acid systems, dosage forms, or delivery technologies.

How does the ’219 patent compare with Xywav and other sodium oxybate products?

Xyrem contains sodium oxybate as an aqueous oral solution. Xywav contains a mixture of oxybate salts designed to reduce sodium exposure. Because the ’219 claims require sodium gamma-hydroxybutyrate at the claimed concentration and do not claim mixed-cation oxybate generally, Xywav’s mixed-salt formulation is not an obvious literal match to the ’219 claims.

Product or platform	Relevant formulation concept	Direct exposure to ’219 claims
Xyrem	Concentrated aqueous sodium oxybate	High historical relevance
Generic sodium oxybate oral solution	Formulation may closely track Xyrem	Product-specific; patent now expired
Xywav	Mixed oxybate salts with reduced sodium	Lower literal relevance to ’219
Lumryz	Extended-release sodium oxybate suspension	Different dosage-form and release technology
Solid or alternative oxybate products	Nontraditional dosage forms	Generally outside the aqueous-solution claims

The expired status of the ’219 patent does not resolve patent questions involving Xywav, Lumryz, controlled-release technology, delivery systems, or later-issued formulation patents.

What generic entry risks remain after the ’219 patent expired?

The principal remaining risks are regulatory and estate-wide rather than specific to U.S. Patent 7,262,219.

Regulatory risks

An ANDA applicant must demonstrate bioequivalence and satisfy FDA requirements for product quality, labeling, risk management, and any applicable controlled-substance obligations. Sodium oxybate is subject to significant abuse, misuse, and diversion controls because gamma-hydroxybutyrate is a controlled substance.

Patent risks

A generic applicant may still confront:

Later-expiring formulation patents;
Method-of-use patents;
Dosing or titration patents;
Controlled-release patents;
Device or dispensing patents;
Manufacturing patents;
Patents covering mixed oxybate salts; and
Patent litigation based on the proposed label or formulation.

Commercial risks

The market may include authorized generics, branded competitors, restricted-distribution requirements, and payer substitution controls. Generic entry can reduce Xyrem revenue even when the entrant does not practice every claim in the historic patent estate.

What is the current commercial significance of U.S. Patent 7,262,219?

The ’219 patent has no current blocking value as an enforceable U.S. patent. Its historical value was substantial because it targeted the commercial Xyrem formulation and could be asserted against a close generic formulation. Its present value is evidentiary and historical:

It identifies the formulation architecture that Jazz sought to protect;
It helps assess whether an older generic product was designed around the Xyrem formulation;
It remains relevant to historical Paragraph IV litigation and settlement analysis;
It does not, by itself, block current generic sodium oxybate approval or launch.

No royalty, licensing, or freedom-to-operate conclusion should be attributed to this patent alone. Any current transaction analysis must examine the surviving patent portfolio, FDA listings, settlement agreements, and the specific generic product.

Key Takeaways

U.S. Patent 7,262,219 covered preservative-free aqueous sodium oxybate at approximately 350 to 750 mg/mL and pH 6.0 to 7.5.
Claim 1 covered eight specified organic acids; claim 4 covered five specified inorganic acids.
Claim 2 narrowed the concentration to approximately 400 to 650 mg/mL.
Claim 3 specifically covered malic acid.
The patent covered composition characteristics, not treatment methods, manufacturing, or dosing.
The Orange Book-listed patent expired on December 17, 2022, with pediatric exclusivity extending protection into 2023.
The patent no longer blocks generic sodium oxybate entry.
Later Xyrem, Xywav, Lumryz, device, method-of-use, and manufacturing patents require separate analysis.
A close copy of the claimed formulation was the highest historical infringement risk.
Current generic-entry risk is determined by the remaining patent estate, FDA requirements, controlled-substance controls, and commercial launch conditions.

FAQs About U.S. Patent 7,262,219

Could a generic sodium oxybate product infringe the ’219 patent if it uses citric acid?

Historically, yes, if the product also met the claimed concentration, pH, aqueous, preservative-free, stability, and microbial-resistance limitations. The patent has expired, so infringement of the expired patent is no longer a current launch barrier.

Does the ’219 patent cover sodium oxybate tablets or capsules?

No. The claims require an aqueous solution. Tablets, capsules, powders, and other solid dosage forms generally fall outside the literal dosage-form limitation.

Does using hydrochloric acid avoid claim 1?

Yes, literally. Hydrochloric acid is not among claim 1’s organic acids. It is expressly listed in independent claim 4, however, so a hydrochloric-acid formulation must be evaluated against claim 4.

Does adding a preservative avoid the ’219 patent?

It may avoid the express “free of preservatives” limitation, but the answer depends on whether the ingredient is legally characterized as a preservative and whether the product remains subject to an equivalent-infringement theory. The patent itself is expired.

Is the ’219 patent relevant to Xywav?

The relevance is limited because Xywav uses a mixed oxybate-salt approach rather than relying solely on sodium gamma-hydroxybutyrate. Product-specific analysis would still be required for other patents in the oxybate portfolio.

References

United States Patent and Trademark Office. (2007). U.S. Patent No. 7,262,219, Pharmaceutical compositions containing gamma-hydroxybutyrate.
U.S. Food and Drug Administration. (n.d.). Approved drug products with therapeutic equivalence evaluations: Xyrem (sodium oxybate) Orange Book patent listing.
U.S. Food and Drug Administration. (n.d.). Patent and exclusivity information for approved drug products.
Jazz Pharmaceuticals, Inc. (2012-2023). Annual reports and Form 10-K filings. U.S. Securities and Exchange Commission.
U.S. District Courts. (2007-2023). Hatch-Waxman litigation records involving Xyrem and sodium oxybate ANDA applicants. PACER.

Country	Patent Number	Estimated Expiration	Supplementary Protection Certificate	SPC Country	SPC Expiration
Austria	238783	⤷ Start Trial
Australia	2059000	⤷ Start Trial
Australia	779354	⤷ Start Trial
>Country	>Patent Number	>Estimated Expiration	>Supplementary Protection Certificate	>SPC Country	>SPC Expiration

Details for Patent: 7,262,219

Summary for Patent: 7,262,219