Details for Patent: 8,778,924

Which drugs does patent 8,778,924 protect, and when does it expire?

Patent 8,778,924 protects MOXATAG and is included in one NDA.

This patent has eleven patent family members in six countries.

Summary for Patent: 8,778,924

Title:	Modified release amoxicillin products
Abstract:	An amoxicillin product comprising: at least one modified release component(s), wherein the at least one modified release component(s) comprises at least amoxicillin and a pharmaceutically acceptable carrier; and wherein when administered to a patient or subject in the fed state said amoxicillin product exhibits a pharmacokinetic profile for amoxicillin in the plasma characterized as follows: (1) the ratio of the portion of the AUC as measured from 2 hours post-administration to 5 hours post-administration to the portion of the AUC as measured from administration to 2 hours post-administration is at least 2.0:1; and (2) the ratio of the portion of the AUC as measured from 5 hours post-administration to 12 hours post-administration to the portion of the AUC as measured from administration to 2 hours post-administration is at least 1.1:1.
Inventor(s):	Henry H. Flanner, Sanna Tolle-Sander, Donald Treacy, Beth A. Burnside, Susan P. Clausen
Assignee:	Shionogi Inc
Application Number:	US11/633,315
Patent Claim Types: see list of patent claims	Use; Compound;

US Patent 8,778,924: Amoxicillin Extended-Release Patent Scope, Expiration, and Competitive Landscape

US Patent 8,778,924 protects a once-daily, multi-pulse amoxicillin dosage form associated with the 775 mg extended-release product Moxatag. Its core limitation is a three-part delivery system: immediate release, first delayed release, and second delayed release. The patent also requires defined fed-state pharmacokinetic ratios, making the claims materially narrower than a general extended-release amoxicillin claim.

The patent is strongest against products that reproduce the claimed layered formulation and pharmacokinetic profile. A conventional immediate-release amoxicillin product, a twice-daily extended-release product, or a formulation using a materially different release architecture would not necessarily fall within the claims.

What drug and formulation does US Patent 8,778,924 protect?

The patent covers a once-a-day amoxicillin product containing:

1. An immediate-release amoxicillin component.
2. A first delayed-release component coated with a methacrylic acid copolymer dispersion.
3. A second delayed-release component coated with both:
   • A methacrylic acid copolymer dispersion; and
   • Hypromellose acetate succinate.

The formulation is designed to release amoxicillin in three temporal phases. The immediate-release fraction releases first. The first delayed-release fraction releases after the immediate-release fraction. The second delayed-release fraction releases after the first delayed-release fraction.

The patent claims are directed to the product architecture, pharmacokinetic performance, dosage amount, excipients, treatment use, and optional inclusion of clavulanate or another beta-lactamase inhibitor. (U.S. Patent No. 8,778,924, 2014).

What is the commercial product associated with the patent?

The claimed product corresponds to Moxatag, an extended-release amoxicillin tablet containing 775 mg of amoxicillin. Moxatag was approved by the FDA for once-daily treatment of certain infections caused by susceptible Streptococcus pyogenes, subject to the approved labeling limitations. (FDA, 2008).

The claims do not cover all amoxicillin products. They focus on a specific extended-release dosage form and, in several claims, a specific pharmacokinetic profile after administration with food.

How many patents cover the claimed amoxicillin product?

The relevant patent estate includes more than US Patent 8,778,924. Moxatag-related patent protection has included earlier and related US patents directed to extended-release amoxicillin formulations. Patent-number and Orange Book coverage must be evaluated by product and listing date because patent families can contain overlapping composition, formulation, use, and continuation claims.

Patent	General subject matter	Relevance
US 8,778,924	Multi-component once-daily amoxicillin product with defined pharmacokinetic ratios	Core formulation and performance patent analyzed here
Earlier related Moxatag patents	Extended-release amoxicillin formulations and related dosage forms	May contain broader, narrower, or overlapping claim coverage
Related continuation or divisional patents	Formulation, dosage, or treatment claims	Can affect generic certification and launch timing

The existence of related patents does not mean that every patent remains enforceable or listed in the FDA Orange Book. Patent-family review must distinguish issued claims, abandoned applications, expired patents, terminal disclaimers, and patents listed for the applicable NDA.

What are the independent claims in US Patent 8,778,924?

The patent has three substantive claim categories.

Claim 1: the principal formulation claim

Claim 1 requires all of the following:

• A once-daily amoxicillin product.
• An immediate-release amoxicillin component.
• A first delayed-release amoxicillin component.
• A first coating comprising a methacrylic acid copolymer dispersion.
• A second delayed-release amoxicillin component.
• A second coating comprising a methacrylic acid copolymer dispersion and hypromellose acetate succinate.
• Sequential release after the immediate-release component.
• A fed-state AUC(2-5)/AUC(0-2) ratio of at least 2.0:1.
• A fed-state AUC(5-12)/AUC(0-2) ratio of at least 1.1:1.
• Upper limits of 10:1 for both ratios.

This is a combination claim. A challenger must address both the physical formulation and the recited pharmacokinetic limitations.

Claim 2: total exposure requirement

Claim 2 adds a bioavailability limitation. The product must achieve an AUC0-inf of at least 75% of the AUC0-inf of an immediate-release amoxicillin product, in either the fed or fasted state.

This limitation creates a potential design-around route. A product that uses a different release system and does not meet the claimed formulation structure may avoid infringement even if its total exposure is similar.

Claim 14: treatment method

Claim 14 covers treating a bacterial infection by administering the product of claim 1. Claims 15 through 26 and 28, 36 through 42, and 52 through 60 extend the treatment claims to dependent formulation embodiments.

These method claims are generally narrower than the corresponding product claims because infringement requires administration for treatment of a bacterial infection, together with all limitations of the referenced product claim.

What dependent claims materially narrow the patent scope?

The most commercially relevant dependent claims are claims 4, 8, 13, 43, 45, 46, 49, and 51.

Claim	Added limitation	Commercial significance
4	About 775 mg amoxicillin	Directly targets the Moxatag strength
8	About 775 mg with enhanced fed-state ratios	Narrows to a specific performance profile
13	About 775 mg with the strongest listed ratio thresholds	Potentially difficult to prove without pharmacokinetic data
43	45% immediate release, 30% first delayed release, 25% second delayed release	Captures the three-pulse dose allocation
45	Specific excipient set for first delayed-release component	Increases formulation specificity
46	Specific excipient set for second delayed-release component	Adds sodium lauryl sulfate and other excipients
49	Combined three-fraction allocation and specified excipients	Narrow but potentially strong against a literal copy
51	775 mg product under claim 43	Closest narrow claim to the commercial embodiment

Claim 43 is particularly important because it defines the dosage distribution:

• Approximately 45% of total amoxicillin in the immediate-release component.
• Approximately 30% in the first delayed-release component.
• Approximately 25% in the second delayed-release component.

For a 775 mg product, those proportions correspond approximately to:

Component	Percentage	Approximate amoxicillin amount
Immediate release	45%	348.75 mg
First delayed release	30%	232.5 mg
Second delayed release	25%	193.75 mg
Total	100%	775 mg

The use of "about" introduces a claim-construction issue. Its scope would depend on the specification, prosecution history, technical meaning, and the degree of variation a skilled formulator would consider acceptable.

What pharmacokinetic profile does the patent require?

The patent uses AUC ratios to define the timing and extent of amoxicillin exposure.

Parameter	Minimum required by claim 1	Upper limit
AUC(2-5) / AUC(0-2), fed state	2.0:1	10:1
AUC(5-12) / AUC(0-2), fed state	1.1:1	10:1

The narrower claims impose higher thresholds:

Claim	AUC(2-5)/AUC(0-2)	AUC(5-12)/AUC(0-2)
5	At least 2.2:1	At least 1.2:1
9	At least 1.2:1	At least 2.4:1
10	At least 2.4:1	At least 1.3:1
11	At least 2.4:1	At least 1.3:1

These limitations are not merely dissolution specifications. They are in vivo pharmacokinetic limitations measured over defined post-dose intervals. A generic applicant seeking to avoid the claims would need to assess whether its product could nevertheless satisfy the same ratios under the doctrine of equivalents, depending on the applicable litigation record.

Why are the AUC limitations important?

The AUC limitations distinguish the claimed product from a formulation that releases most of its dose shortly after administration. They require sustained exposure during both the two-to-five-hour interval and the five-to-twelve-hour interval relative to the first two hours.

The claim structure creates two separate infringement questions:

1. Does the accused product contain the required three release components and coating materials?
2. Does administration produce the required AUC ratios?

A product can potentially avoid literal infringement by failing either category of limitation.

What formulation patents protect the Moxatag-type delivery system?

The patent protects a multi-particulate or multi-component dosage design rather than a single uniform polymer matrix. The technical elements include:

Immediate-release component

The immediate-release component contains amoxicillin and may include povidone under claims 44 and 47.

First delayed-release component

The first delayed-release component contains amoxicillin coated with a methacrylic acid copolymer dispersion. Claim 45 adds:

• Microcrystalline cellulose.
• Povidone.
• Castor oil.
• Talc.
• Triethyl citrate.

Second delayed-release component

The second delayed-release component contains amoxicillin coated with a methacrylic acid copolymer dispersion and hypromellose acetate succinate. Claim 46 adds:

• Microcrystalline cellulose.
• Povidone.
• Castor oil.
• Talc.
• Triethyl citrate.
• Sodium lauryl sulfate.

The coating requirements are central. A formulation using a different enteric polymer, a different polymer combination, or a single delayed-release population may fall outside the literal language of claims 1 and its dependents.

When does US Patent 8,778,924 lose exclusivity?

The patent issued on July 15, 2014. Its relevant priority chain and any patent-term adjustment or terminal disclaimer determine the enforceable expiration date. A standard 20-year patent-term calculation from the earliest effective nonprovisional filing places the ordinary expiration in the 2026-2027 period, subject to adjustment under 35 U.S.C. §§ 154 and 156.

The patent’s practical exclusivity date should be determined from the USPTO patent-term data and the FDA Orange Book listing for the applicable NDA. Patent expiration and regulatory exclusivity are separate:

Exclusivity type	Relevance to Moxatag-type product
Patent term	Determines enforceable exclusion under patent law
New-drug exclusivity	May delay certain FDA approvals independently of patent expiry
Pediatric exclusivity	Can add six months if granted
Orphan exclusivity	Generally not implicated by this product
Orange Book listing	Gives the NDA holder a mechanism to trigger patent certification and potential litigation

The patent does not create perpetual protection for once-daily amoxicillin. After expiration, a generic product can enter if it satisfies FDA approval requirements and is not blocked by another unexpired patent or regulatory exclusivity period.

What is the Orange Book status of US Patent 8,778,924?

The relevant FDA inquiry is whether US Patent 8,778,924 is listed for the Moxatag NDA and whether the listing remains active. Orange Book listings are product-specific. A patent may be listed for a formulation, method of use, or drug substance only if it satisfies FDA listing rules.

For a generic applicant, the consequences are material:

• A listed patent generally requires a patent certification.
• A Paragraph IV certification alleges that the listed patent is invalid, unenforceable, or not infringed.
• Notice of a Paragraph IV certification can trigger a patent-infringement action.
• A timely action can create a 30-month stay of approval under the Hatch-Waxman framework, subject to statutory exceptions.

The Orange Book does not decide infringement or validity. It records the listing and regulatory consequences of a generic certification. (FDA, 2024a; 21 U.S.C. § 355).

Have generic companies filed Paragraph IV challenges?

The supplied claim text does not establish whether a Paragraph IV certification has been filed against US Patent 8,778,924. A reliable answer requires review of FDA Paragraph IV notice records, ANDA litigation dockets, and the current Orange Book entry.

The patent is vulnerable to a Paragraph IV challenge on several grounds:

1. Obviousness: A challenger could combine known immediate-release and enteric-release amoxicillin technologies with pharmacokinetic optimization.
2. Written description and enablement: The challenger could argue that the broad range of claimed ratios, doses, and formulations is not adequately supported across the full claim scope.
3. Indefiniteness: Terms such as "about," "initiates release," and "equivalent extent of absorption" could be challenged, although pharmacokinetic claim language can be definite when the testing methodology is adequately specified.
4. Noninfringement: A generic could use a different polymer system, release sequence, dose allocation, or pharmacokinetic profile.
5. Anticipation: Earlier extended-release amoxicillin disclosures would need to disclose every limitation, including the specific combination of coating materials and the required AUC ratios.

The strongest validity challenge would likely focus on obviousness. The strongest noninfringement position would likely focus on the coating combination and the pharmacokinetic ratio limitations.

What patent litigation affects US Patent 8,778,924?

No litigation outcome can be inferred from the claim text alone. The relevant litigation analysis should distinguish:

• Actions brought after Paragraph IV notice.
• Declaratory-judgment actions.
• ANDA litigation involving Moxatag.
• Patent settlements that establish a licensed or agreed generic-entry date.
• Appeals concerning claim construction, obviousness, written description, or infringement.

A patent litigation search should use the patent number, the Moxatag NDA number, the patent owner, and the ANDA applicant as separate search variables. Patent litigation may identify additional related patents that are more commercially important than US 8,778,924.

What generic entry risks exist for Moxatag?

The risk depends on the generic’s formulation and approval pathway.

Product-by-product risk assessment

Generic strategy	Likely patent risk
Copy of 775 mg three-pulse formulation	High
Same polymers and dose allocation, different excipient quantities	High to moderate
Same release profile but different delayed-release polymers	Moderate
Two-pulse extended-release product	Lower against claim 1
Single matrix extended-release product	Lower against claim 1
Immediate-release amoxicillin product	Low under these claims
Amoxicillin-clavulanate formulation	Depends on whether it retains the claimed amoxicillin architecture
Product with materially different AUC timing	Lower, subject to doctrine-of-equivalents analysis

Claims 29 through 42 broaden the claimed product to formulations that also contain clavulanate or another beta-lactamase inhibitor. Those claims could be relevant to an amoxicillin-clavulanate product only if the product also satisfies the underlying release-component and pharmacokinetic limitations.

Does the patent create biosimilar risk?

No. Amoxicillin is a small-molecule drug, not a biologic. The relevant competitive pathway is an abbreviated new drug application, not a biosimilar application under the Biologics Price Competition and Innovation Act.

The primary regulatory and commercial risks are:

• ANDA approval.
• Paragraph IV certification.
• Patent litigation.
• Paragraph III certification with approval after patent expiry.
• A non-infringing alternative extended-release formulation.

How strong is the patent estate?

US Patent 8,778,924 has a mixed strength profile.

Issue	Assessment
Product differentiation	Strong, because the claim requires a defined multi-component architecture
Literal infringement against an exact copy	Potentially strong
Breadth against alternative extended-release systems	Limited
Pharmacokinetic definition	Useful for distinguishing prior art, but increases proof complexity
775 mg commercial targeting	Strong commercial relevance, narrower scope
Excipient claims	Narrow and design-around susceptible
Treatment claims	Secondary protection; dependent on use and product limitations
Obviousness exposure	Material, because multiparticulate and enteric-release technologies were known
Regulatory leverage	Depends on current Orange Book listing and remaining patent term

The patent’s value is concentrated in its ability to block a close formulation copy. It is less effective as a broad barrier against all once-daily amoxicillin products.

How does US Patent 8,778,924 compare with conventional amoxicillin protection?

Product type	Covered by claim 1?	Principal reason
Immediate-release amoxicillin capsule	Generally no	Lacks delayed-release components
Immediate-release amoxicillin tablet	Generally no	Lacks sequential delayed release
Conventional extended-release matrix	Not necessarily	May lack the two specified delayed-release populations
Once-daily three-pulse formulation	Potentially yes	May satisfy structural and PK limitations
Amoxicillin-clavulanate immediate-release product	Generally no	Does not satisfy the claimed delivery architecture
Amoxicillin-clavulanate three-pulse product	Potentially yes	Claims 29-42 address beta-lactamase inhibitor combinations

The patent does not claim the amoxicillin molecule, the beta-lactam antibiotic class, or the general concept of once-daily antibacterial therapy.

What manufacturing and intellectual-property barriers exist?

The manufacturing barrier is moderate. The formulation requires separate amoxicillin populations with different coating systems and release timing. Commercial manufacture may require:

• Production of an immediate-release fraction.
• Manufacture and coating of the first delayed-release fraction.
• Manufacture and coating of the second delayed-release fraction.
• Blending or compression without damaging the coatings.
• Control of coating thickness and polymer ratios.
• Dissolution testing for each release phase.
• Clinical or comparative pharmacokinetic testing to establish the required exposure pattern.

The patent does not necessarily prevent manufacture of the same excipients for other products. It creates risk when the complete combination is made, sold, or used in a product meeting the claim limitations.

What is the likely generic launch scenario?

The principal launch scenarios are:

1. At-risk launch before patent expiry: The applicant launches after a Paragraph IV challenge without waiting for final patent resolution. This creates substantial damages and injunction exposure if the patent is upheld and infringed.
2. Launch after patent expiry: The applicant files a Paragraph III certification or otherwise waits for the relevant patent term to end.
3. Licensed entry under settlement: The patent owner and generic applicant agree to an earlier entry date, subject to settlement terms and antitrust scrutiny.
4. Non-infringing alternative: The applicant develops a different extended-release design that does not satisfy the structural or pharmacokinetic limitations.

A generic applicant is more likely to pursue a formulation design-around when the commercial market is too small to justify a full Paragraph IV campaign or when the patent’s remaining term is short.

What geographic coverage does the patent provide?

US Patent 8,778,924 provides protection only in the United States. Corresponding foreign-family rights, if any, require separate analysis by jurisdiction. Patent expiration, claim scope, opposition practice, regulatory linkage, and generic-entry rules vary across Europe, Canada, Japan, Australia, and other markets.

US patent protection does not block:

• Manufacture outside the United States for non-US markets.
• Sale of a non-infringing product in foreign jurisdictions.
• Foreign regulatory approval after the expiration of corresponding local rights.

Key Takeaways

• US Patent 8,778,924 covers a once-daily, three-phase amoxicillin delivery system.
• The core claim requires immediate release plus two sequential delayed-release components.
• The first delayed-release component uses a methacrylic acid copolymer dispersion.
• The second uses a methacrylic acid copolymer dispersion and hypromellose acetate succinate.
• The claim also requires defined fed-state AUC ratios.
• Dependent claims specifically target a 775 mg product and a 45%/30%/25% dose allocation.
• The patent is most relevant to Moxatag-type formulation copies, not conventional immediate-release amoxicillin.
• Claims 29 through 42 extend selected embodiments to products containing clavulanate or another beta-lactamase inhibitor.
• Amoxicillin has generic, not biosimilar, competition.
• Generic risk depends heavily on the current Orange Book listing, remaining patent term, Paragraph IV activity, and related Moxatag patents.
• The patent is commercially meaningful but vulnerable to design-around strategies using different release architectures or coating systems.

FAQs About US Patent 8,778,924

Is US Patent 8,778,924 a drug substance patent?

No. It is principally a formulation and pharmacokinetic patent. It does not claim amoxicillin as a chemical compound.

Does the patent cover all once-daily amoxicillin products?

No. A competing product must satisfy the claim’s structural limitations and, for the principal claim, the specified pharmacokinetic ratios.

Does a different enteric polymer avoid the patent?

It may avoid literal infringement if the alternative polymer does not meet the claim language requiring the specified methacrylic acid copolymer and hypromellose acetate succinate combination. The final result would depend on claim construction and equivalents analysis.

Can an amoxicillin-clavulanate product infringe the patent?

Yes, potentially. Claims 29 through 42 add clavulanate or another beta-lactamase inhibitor to selected claimed embodiments. The underlying three-component release and pharmacokinetic limitations still apply.

Is a Paragraph IV challenge required for every generic amoxicillin product?

No. A certification is relevant to a generic applicant seeking approval for a product that references an NDA with listed patents. A conventional immediate-release amoxicillin product may follow a different regulatory pathway and would not necessarily implicate this formulation patent.

References

1. U.S. Patent No. 8,778,924. (2014). Amoxicillin product. United States Patent and Trademark Office.

2. U.S. Food and Drug Administration. (2008). Moxatag (amoxicillin extended-release tablets) prescribing information. FDA.

3. U.S. Food and Drug Administration. (2024a). Approved drug products with therapeutic equivalence evaluations, Orange Book. FDA.

4. U.S. Food and Drug Administration. (2024b). Abbreviated new drug application approvals and patent certifications. FDA.

5. 21 U.S.C. § 355. New drug applications and abbreviated applications.

6. 35 U.S.C. §§ 154, 156. Patent term and patent term extension.

Drugs Protected by US Patent 8,778,924

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Patented / Exclusive Use	Submissiondate
Pragma	MOXATAG	amoxicillin	TABLET, EXTENDED RELEASE;ORAL	050813-001	Jan 23, 2008		DISCN	Yes	No	8,778,924		Y	Y		METHOD OF TREATING TONSILLITIS AND/OR PHARYNGITIS SECONDARY TO STREPTOCOCCUS PYOGENES IN A ONCE-A-DAY AMOXICILLIN PRODUCT

International Family Members for US Patent 8,778,924

Country	Patent Number	Estimated Expiration	Supplementary Protection Certificate	SPC Country	SPC Expiration
Australia	2006321782
Australia	2006351475
Canada	2635378
Canada	2635606