US Patent 7,816,396: Glycopyrrolate Oral Solution, Sialorrhea Treatment Claims, and Patent Landscape

US Patent 7,816,396 protects a specific clinical-use protocol for treating sialorrhea with orally administered liquid glycopyrrolate under fasting conditions. Its core limitations are the liquid dosage form, 1 mg to 10 mg dose, defined fasting window, and pharmacokinetic thresholds comparing fed and fasted administration. The patent does not broadly cover glycopyrrolate, all treatment of sialorrhea, or every glycopyrrolate oral formulation.

The patent has an issued term tied to a May 4, 2004 priority date and is listed in public patent records as having a 2025 expiration date, subject to any applicable patent-term adjustment or regulatory term extension. Because the patent term has reached or passed its ordinary expiration date, its present value is primarily historical, litigation-related, and relevant to the interpretation of the Cuvposa development program rather than to a continuing US exclusionary position. [1][2]

What does US Patent 7,816,396 cover?

The patent covers methods of treating sialorrhea by administering glycopyrrolate in a liquid solution while controlling food intake around administration.

The independent claims are claims 1 and 4:

Claim	Core subject matter	Key pharmacokinetic limitations
1	Treatment of sialorrhea with 1 mg to 10 mg oral glycopyrrolate liquid under fasting conditions	Fasted-to-fed AUC0-∞ ratio greater than 1.8
4	Treatment of sialorrhea with 1 mg to 10 mg oral glycopyrrolate liquid under fasting conditions	Fasted-to-fed Cmax ratio greater than 1.1; fasted-to-fed AUC0-24 ratio greater than 1.8; fasted AUC0-24 greater than 1.0 ng·hr/mL

Claims 2, 3, 5, 7, and 8 impose higher or additional AUC requirements. Claim 6 adds an AUC0-∞ comparison to claim 4.

Each independent claim requires the patient to avoid food from 30 minutes before administration through one hour after administration. The fasting condition therefore lasts at least 90 minutes around the dose.

What are the key limitations of claims 1 through 8?

Claim 1: AUC0-∞ and fasting-window method

Claim 1 requires all of the following:

A human patient.
Treatment of sialorrhea.
Oral administration.
Glycopyrrolate.
A liquid solution.
A dose of about 1 mg to about 10 mg.
Administration under fasted conditions.
A fasted-to-fed AUC0-∞ ratio greater than 1.8.
No food during the period beginning 30 minutes before dosing and ending one hour after dosing.

The claim is narrower than a conventional method-of-treatment claim because it requires a measurable pharmacokinetic relationship. A product may contain glycopyrrolate and be approved for sialorrhea yet fall outside claim 1 if the relevant fasted-to-fed AUC ratio is not greater than 1.8 or if the administration instructions do not satisfy the specified food restriction.

Claims 2 and 3: Absolute fasted exposure

Claim 2 requires the fasted AUC0-∞ to exceed 1.0 ng·hr/mL. Claim 3 raises that threshold to greater than 1.7 ng·hr/mL.

These claims add absolute exposure limitations to claim 1. They are narrower than claim 1 because a product must satisfy both the relative fasted-to-fed ratio and the specified absolute AUC level.

Claim 4: Cmax and AUC0-24 method

Claim 4 is an independent method claim with a different pharmacokinetic structure. It requires:

A fasted increase in Cmax compared with fed administration;
A fasted increase in AUC0-24 compared with fed administration;
A fasted-to-fed Cmax ratio greater than 1.1;
A fasted-to-fed AUC0-24 ratio greater than 1.8;
Fasted AUC0-24 greater than 1.0 ng·hr/mL;
The same 1 mg to 10 mg liquid oral dose;
Treatment of sialorrhea;
The same no-food period.

The use of AUC0-24 rather than AUC0-∞ may matter where terminal-phase sampling is incomplete or where the pharmacokinetic study does not reliably establish total exposure to infinity.

Claims 5 through 8: Narrower pharmacokinetic embodiments

Claim 5 raises the fasted AUC0-24 threshold to greater than 1.7 ng·hr/mL.

Claim 6 adds the fasted-to-fed AUC0-∞ ratio greater than 1.8.

Claim 7 adds a fasted AUC0-∞ greater than 1.0 ng·hr/mL.

Claim 8 raises that AUC0-∞ threshold to greater than 1.7 ng·hr/mL.

The claims form two related protection groups:

Group	Independent claim	Added exposure metrics
AUC0-∞ group	Claim 1	Claims 2 and 3 add absolute AUC0-∞ thresholds
Cmax/AUC0-24 group	Claim 4	Claims 5 through 8 add AUC0-24 and AUC0-∞ requirements

How strong is the patent scope for glycopyrrolate oral solution?

The patent scope is technically specific but commercially focused. Its strength depends on whether a competing product or prescribing protocol satisfies the pharmacokinetic limitations.

Scope that is likely captured

A competing product is potentially within the literal scope if it:

Is a liquid oral glycopyrrolate product;
Is dosed at approximately 1 mg to 10 mg;
Is used to treat sialorrhea;
Is administered with the claimed fasting interval;
Produces the claimed exposure ratios and absolute exposure levels.

A generic version that copies the reference product’s concentration, dose instructions, and fasting administration requirements could face a substantial claim-mapping issue if its pharmacokinetic profile is materially similar.

Scope that is likely outside the claims

The claims do not expressly cover:

Intravenous, intramuscular, transdermal, or inhaled glycopyrrolate;
Tablets or capsules that are not administered as a liquid solution;
Doses below approximately 1 mg or above approximately 10 mg;
Treatment of indications other than sialorrhea;
Administration without the specified fasting window;
A liquid product whose pharmacokinetic ratios do not meet the stated thresholds;
Nonhuman use;
A formulation claim directed to excipients, pH, preservatives, flavoring, or manufacturing steps.

The fasting limitations are particularly important. A competitor could attempt to differentiate by labeling administration with food, by using a dosage form with different food-effect behavior, or by developing a formulation that does not produce the claimed exposure relationship.

What formulation patents protect Cuvposa and glycopyrrolate oral solution?

US Patent 7,816,396 is primarily a method-of-use and pharmacokinetic patent, not a conventional composition patent. It does not claim a particular excipient system, preservative package, flavor, pH range, or manufacturing process in the claims provided.

Cuvposa is an FDA-approved glycopyrrolate oral solution for reducing chronic severe drooling in pediatric patients aged 3 to 16 years with neurologic conditions. The FDA-approved product is a 1 mg/5 mL oral solution, equivalent to 0.2 mg/mL. Its label includes food-related administration instructions because food affects glycopyrrolate exposure. [3]

The distinction is material:

IP category	Covered by US 7,816,396 claims?
Glycopyrrolate active ingredient generally	No
Any glycopyrrolate oral product	No
Liquid oral glycopyrrolate used for sialorrhea	Potentially, if all claim limitations are met
Specific excipient composition	Not based on the supplied claims
Manufacturing process	Not based on the supplied claims
Food-effect administration protocol	Yes
Pharmacokinetic exposure profile	Yes
Tablet or capsule dosage form	Not expressly

Older patents may cover glycopyrrolate compounds, anticholinergic uses, or particular formulations, but those rights are separate from the claims of US 7,816,396. The active ingredient itself is long-established, so the commercial protection associated with this patent came from the approved liquid administration method and food-effect profile rather than compound exclusivity.

What is the FDA and Orange Book status of the patent?

Cuvposa was approved by FDA in July 2010 under NDA 022571. The approved indication is severe drooling associated with neurologic conditions in pediatric patients. [3][4]

The Orange Book historically listed US 7,816,396 in connection with Cuvposa. Orange Book listing does not mean that every claim in the patent covers every glycopyrrolate product. It indicates that the NDA sponsor identified the patent as relevant to the approved drug and required certification or notice in connection with certain ANDA submissions. [4]

The relevant regulatory framework was:

Paragraph I certification: no patent information was submitted;
Paragraph II certification: the patent had expired;
Paragraph III certification: the applicant would wait until patent expiry;
Paragraph IV certification: the patent was invalid, unenforceable, or would not be infringed.

For a small-molecule oral solution, an applicant would use the ANDA pathway rather than the biosimilar pathway. Biosimilar concepts do not apply because glycopyrrolate is a chemically synthesized small molecule, not a biologic.

When did US Patent 7,816,396 lose exclusivity?

The patent’s ordinary term is associated with the May 4, 2004 priority date and a 20-year patent term framework. Public patent records identify the expected expiration as May 4, 2025, subject to any recorded patent-term adjustment. [1][2]

The relevant timeline is:

Event	Date
Earliest claimed priority	May 4, 2004
US patent application filing period	2005
Patent issued	October 19, 2010
Cuvposa FDA approval	July 28, 2010
Expected ordinary patent expiration	May 4, 2025

Regulatory exclusivity and patent exclusivity are separate. FDA approval in 2010 did not convert the patent into permanent protection. Any orphan-drug, pediatric, or clinical-investigation exclusivity would have had its own term and would not extend the patent’s claim scope.

Which companies challenged or could challenge the patent?

The practical challengers for this product class would be ANDA applicants seeking approval for glycopyrrolate oral solution. Their legal options would include:

Paragraph III certification and launch after patent expiry.
Paragraph IV certification asserting invalidity or noninfringement.
A design-around formulation or dosing protocol.
A product label that omits the patented fasting instructions, subject to induced-infringement and regulatory-label analysis.

Publicly available FDA and patent records identify the product and patent relationship, but the supplied information does not establish a complete, verified list of all ANDA applicants, Paragraph IV notices, settlement agreements, or district-court outcomes. A definitive litigation chronology cannot be stated from the patent claims alone.

What patent litigation and settlement risks affect generic launch?

Before expiration, the highest-risk scenario for a generic liquid glycopyrrolate applicant would have been a Paragraph IV filing that triggered a Hatch-Waxman suit. A timely suit could have created a statutory 30-month stay of ANDA approval, depending on filing timing and applicable FDA procedures. [5]

The principal litigation issues would have been:

Infringement

The patent holder would need to establish that the proposed product and its labeled use satisfy each limitation. The most contested elements would likely be:

Whether the product is administered as a liquid solution;
Whether the dose is “about” 1 mg to “about” 10 mg;
Whether the proposed label directs treatment of sialorrhea;
Whether the label requires the claimed fasting interval;
Whether the fasted-to-fed AUC and Cmax ratios are inherent or directly established.

Validity

Potential validity arguments would focus on:

Anticipation by prior food-effect pharmacokinetic studies;
Obviousness based on known glycopyrrolate pharmacology and routine fed-versus-fasted testing;
Written description or enablement of the numerical pharmacokinetic thresholds;
Claim construction of “about,” “fasted conditions,” and the stated AUC ratios.

Induced infringement

A label that instructs physicians or patients to administer the product during the claimed fasting interval could create a greater induced-infringement risk than a label that permits administration without the patented food restriction. The analysis would depend on the exact approved labeling, evidence of intent, and whether the clinical use necessarily practices the claim.

How does US Patent 7,816,396 compare with broader glycopyrrolate patents?

Patent category	Typical protected subject matter	Relationship to US 7,816,396
Compound patents	Glycopyrrolate molecule or salt	Separate and generally much older
Formulation patents	Excipients, concentration, stability, taste, preservatives	Not present in the supplied claims
Manufacturing patents	Mixing, filtration, sterilization, filling	Not present in the supplied claims
Method-of-use patents	Treating sialorrhea or other secretory disorders	Closest category
Pharmacokinetic patents	Food-effect ratios and exposure thresholds	Core category of US 7,816,396
Regulatory exclusivity	FDA approval-based marketing protection	Separate from patent claims

The patent’s commercial strategy was to protect administration of a known drug in the specific oral liquid format used for pediatric sialorrhea treatment. It did not create a broad monopoly over glycopyrrolate.

What generic launch scenarios exist after patent expiration?

After patent expiry, the main launch scenarios are:

An ANDA applicant markets an equivalent 1 mg/5 mL oral solution.
A manufacturer launches a different concentration requiring a different volume per dose.
A competitor markets a formulation with different excipients or preservative systems.
A generic sponsor uses labeling that does not reproduce the patented fasting protocol.
A manufacturer supplies glycopyrrolate for off-label adult sialorrhea treatment, subject to applicable regulatory and commercial constraints.

Manufacturing barriers are comparatively modest because glycopyrrolate is an established small molecule and the claimed patent does not require a complex delivery system. The principal barriers are pharmaceutical-quality controls, stability of the aqueous solution, taste masking, preservative performance, container compatibility, and FDA bioequivalence requirements.

What is the commercial exposure associated with the patent?

Cuvposa’s revenue exposure was concentrated in a pediatric orphan-oriented market rather than the entire glycopyrrolate market. The patent was most relevant to products competing with the approved oral solution for pediatric neurologic sialorrhea.

A competitor to injectable or tablet glycopyrrolate would not necessarily compete directly with Cuvposa or practice these claims. A liquid oral product positioned for the same pediatric indication would present the highest historical patent overlap.

No reliable revenue figure can be assigned to US Patent 7,816,396 from the claims or FDA label alone. The patent’s commercial importance is better measured by its relationship to the Cuvposa NDA, approved dosage form, and the absence of compound-level exclusivity.

Key Takeaways

US Patent 7,816,396 is a method-of-treatment patent for sialorrhea.
The claims require oral liquid glycopyrrolate at approximately 1 mg to 10 mg.
The patient must avoid food from 30 minutes before dosing through one hour after dosing.
The claims rely on fasted-versus-fed pharmacokinetic ratios involving AUC, Cmax, or both.
The patent does not broadly claim glycopyrrolate, all oral formulations, tablets, injectable products, or manufacturing processes.
Claims 1 and 4 are independent; claims 2, 3, and 5 through 8 add narrower exposure thresholds.
The patent was associated with Cuvposa, FDA-approved under NDA 022571.
The ordinary patent term is identified in public records as expiring May 4, 2025, subject to any patent-term adjustment.
Generic applicants would have used the ANDA pathway and could have raised Paragraph III or Paragraph IV certifications.
Biosimilar regulation is not relevant because glycopyrrolate is a small molecule.
The strongest historical design-around strategies involved changing the dosage form, food instructions, dose range, or pharmacokinetic profile.

Frequently Asked Questions

Does US Patent 7,816,396 cover glycopyrrolate tablets?

No. The supplied claims require glycopyrrolate in a liquid solution. A tablet would not literally satisfy the liquid-solution limitation, although other patents or regulatory requirements could remain relevant.

Does the patent cover adult treatment of sialorrhea?

Potentially, if all claim limitations are met. The claims require a human patient but do not expressly limit the patient to children. The indication, dose, liquid format, fasting interval, and pharmacokinetic limitations must still be satisfied.

Is Cuvposa a biologic subject to biosimilar competition?

No. Cuvposa contains glycopyrrolate, a chemically synthesized small molecule. Competition proceeds through the generic-drug and ANDA framework, not the biosimilar pathway.

Can a generic glycopyrrolate solution avoid the patent by changing its concentration?

Changing concentration may avoid infringement only if the resulting product or labeled administration does not satisfy every claim limitation. A concentration change alone may not be sufficient if the administered dose, fasting instructions, and pharmacokinetic profile remain within the claims.

Does patent expiration eliminate FDA approval requirements?

No. Patent expiration removes the patent-based exclusionary right but does not eliminate FDA requirements for an ANDA, manufacturing controls, bioequivalence, labeling, or approval of a competing oral solution.

References

United States Patent and Trademark Office. (2010). US Patent No. 7,816,396, Methods for treating sialorrhea.
Google Patents. (n.d.). US7816396B2: Methods for treating sialorrhea.
U.S. Food and Drug Administration. (2010). Cuvposa (glycopyrrolate) oral solution prescribing information.
U.S. Food and Drug Administration. (n.d.). Approved drug products with therapeutic equivalence evaluations: Orange Book.
U.S. Food and Drug Administration. (n.d.). Abbreviated new drug application submissions: Refuse-to-receive standards and patent certification procedures.

Details for Patent: 7,816,396

Summary for Patent: 7,816,396