United States Patent 7,807,680: Aripiprazole Depot Formulation Scope, Validity and Patent Landscape

U.S. Patent No. 7,807,680 covers a sterile, freeze-dried aripiprazole formulation that is reconstituted into an injectable suspension capable of releasing aripiprazole for at least one to four weeks. Its strongest commercial relevance is the combination of micronized aripiprazole, carboxymethylcellulose, mannitol, phosphate buffer, a freeze-dried cake, and a controlled-release injectable suspension.

The claims reach both the formulation and its manufacturing process. Claims 1-24 and 30-38 primarily protect product characteristics and composition. Claims 25-29 and 31-34 protect sterile processing, wet milling, particle-size reduction, freeze-drying and crystal-form outcomes. The patent is closely aligned with the technical architecture of long-acting aripiprazole products such as Abilify Maintena, although product infringement requires a limitation-by-limitation comparison against the approved product and any accused generic.

What does U.S. Patent 7,807,680 protect?

The patent protects five linked technical elements:

Aripiprazole particles with a mean size of approximately 1-10 microns.
One or more suspending agents.
A sterile freeze-dried cake made from a homogeneous aqueous suspension.
Reconstitution with water into a homogeneous injectable suspension.
In-vivo release lasting at least one week, and in narrower claims at least two, three or four weeks.

The independent formulation claims are drafted with the transitional term “comprises.” That language generally permits additional excipients or processing features, provided all expressly recited elements are present.

Core claim architecture

Claim group	Protected subject matter	Principal limitations
Claims 1-3	Broad freeze-dried controlled-release formulation	1-10 micron aripiprazole, suspending agent, sterile cake, homogeneous suspension, at least two or three weeks of release
Claims 4-9	Buffered and bulking-agent formulations	Suspending agent, bulking agent, buffer, optional pH adjuster, generally three to four weeks of release
Claims 10-15	Crystal-form limitations	Anhydrous crystals or monohydrate; specifically Anhydride Crystals B or Hydrate A
Claims 16-20	Quantitative composition and commercial-dose embodiments	1-40% aripiprazole, 0.2-10% suspending agent, 1-10% bulking agent and 0.02-2% buffer
Claims 21-24	Monohydrate and shorter-duration formulations	At least two weeks under claim 21 and at least one week under claim 22
Claims 25-29	Manufacturing method	Sterile bulk drug, sterile vehicle, primary suspension, particle-size reduction and freeze-drying
Claims 30, 35-38	Narrow particle-size and concentration ranges	2-4 micron, 1-5 micron and approximately 2.5 micron embodiments
Claims 31-34	Product-by-process claims	Monohydrate suspension prepared through the specified sterile milling and freeze-drying process

How broad are claims 1, 21 and 22?

Claims 1, 21 and 22 provide the broadest formulation coverage.

Claim 1 requires a freeze-dried aripiprazole cake made from a homogeneous aqueous suspension. The reconstituted product must be homogeneous, contain 0.1-600 mg/mL of aripiprazole and release the drug for at least two weeks. Claim 21 adds the monohydrate form. Claim 22 lowers the release threshold to at least one week but does not require the monohydrate.

The practical scope is narrower than the phrase “controlled release aripiprazole formulation” might suggest. A potentially infringing product must satisfy the full combination, including:

Sterility.
Freeze-dried cake morphology or the claimed freeze-dried form.
Aqueous suspension before lyophilization.
Homogeneity after reconstitution.
Micronized particle size.
Injectable concentration.
The claimed duration of release.

A conventional ready-to-use suspension, a nonsterile product, an oil-based depot, an implant, a polymer microsphere and an extended-release formulation that does not use a freeze-dried cake would generally fall outside the literal wording of these claims unless another claim or doctrine applies.

Effect of the release-period limitation

The release-period limitation is central. It narrows the claims to products demonstrating in-vivo release for the stated period. Claims 2, 6-9 and 19-20 impose three- or four-week limitations. Claims 21 and 22 create alternative coverage for monohydrate and one-week products.

The term “releases aripiprazole over a period” may require evidence from pharmacokinetic, pharmacodynamic, in-vitro release or other product-performance testing, depending on claim construction and the prosecution history. It creates a potentially significant evidentiary burden in an infringement dispute because particle size and excipient content can be measured directly, while release duration may require testing or regulatory records.

What formulations are protected by the patent?

The most commercially specific formulation is claim 18.

Claim 18 formulation matrix

Component	Formulation A	Formulation B	Formulation C
Aripiprazole, mean particle size 1-10 microns	100 mg/mL	200 mg/mL	400 mg/mL
Carboxymethylcellulose	9 mg/mL	9 mg/mL	9 mg/mL
Mannitol	45 mg/mL	45 mg/mL	45 mg/mL
Sodium phosphate	0.8 mg/mL	0.8 mg/mL	0.8 mg/mL
Sodium hydroxide	Quantity sufficient to pH 7	Quantity sufficient to pH 7	Quantity sufficient to pH 7
Water for injection	Quantity sufficient to 1 mL	Quantity sufficient to 1 mL	Quantity sufficient to 1 mL

Claim 18 is narrower than claim 1 because it requires the specified excipients and the three listed aripiprazole concentrations. It is potentially stronger in litigation when an accused product matches the composition, because quantitative comparison is more straightforward.

The claims also cover broader excipient classes:

Suspending agents: carboxymethylcellulose, hydroxypropyl cellulose, hydroxypropylethyl cellulose, hydroxypropylmethyl cellulose and polyvinylpyrrolidone.
Bulking agents: mannitol, sucrose, maltose, lactose, xylitol and sorbitol.
Buffers: sodium phosphate, potassium phosphate and TRIS buffer.

Claims 16, 35 and 36 add concentration ranges. Claim 36 is particularly narrow, requiring approximately 2.5 micron particles, 5-20% aripiprazole, 0.5-5% suspending agent, 4-5% bulking agent and 0.03-1% buffer.

Does the patent cover aripiprazole monohydrate?

Yes. Claims 10-15, 21 and 31-34 expressly cover aripiprazole monohydrate. Claims 11, 13 and 15 identify “Aripiprazole Hydrate A.” Other claims cover anhydrous crystals and “Aripiprazole Anhydride Crystals B.”

The crystal-form limitations are important because aripiprazole solid form can affect:

Particle-size reduction.
Suspension stability.
Reconstitution behavior.
Sedimentation.
Dissolution rate.
Long-acting pharmacokinetics.
Freeze-drying performance.

A product using a different crystal form may avoid claims limited to Hydrate A or Anhydride Crystals B, but it may still fall within claims that recite only “aripiprazole” and the particle-size, cake and release limitations.

What process does U.S. Patent 7,807,680 protect?

Claims 25-29 protect a sterile manufacturing sequence:

Prepare sterile bulk aripiprazole with the desired particle-size distribution.
Prepare a sterile vehicle containing one or more suspending agents.
Combine the drug and vehicle into a sterile primary suspension.
Reduce the mean particle size to approximately 1-10 microns.
Freeze-dry the final sterile suspension into a cake.

Claims 26 and 27 narrow the particle-size reduction step to wet milling and wet ball milling. Claims 28 and 29 distinguish freeze-drying conditions that produce monohydrate or anhydrous crystals.

Process claim vulnerabilities and advantages

The process claims can be important where formulation analysis cannot establish every product limitation. They create a separate infringement theory if manufacturing records show:

Sterile preparation before milling.
Wet milling or wet ball milling.
Milling in the presence of the suspending vehicle.
Freeze-drying of the sterile final suspension.
The claimed temperature sequence.

Their weakness is access to evidence. Manufacturing-process claims often require discovery, regulatory inspection records, batch records, supplier information or process-development documents. A generic applicant may seek to avoid those claims by using a different particle-size process, a different sterilization sequence or a non-ball-milling technique.

How does the patent compare with a commercial long-acting aripiprazole product?

The claim set has substantial technical overlap with the formulation profile publicly associated with Abilify Maintena. FDA labeling describes Abilify Maintena as a long-acting aripiprazole injection supplied as a powder requiring reconstitution before intramuscular administration. The product is supplied in 300 mg and 400 mg strengths and uses excipients including carboxymethylcellulose sodium, mannitol and phosphate components [2].

Attribute	Patent claims	Abilify Maintena public product information
Active ingredient	Aripiprazole	Aripiprazole
Dosage form	Sterile freeze-dried cake or freeze-dried formulation	Powder requiring reconstitution
Administration	Injectable	Intramuscular injection
Controlled release	At least one to four weeks, depending on claim	Monthly long-acting administration
Suspending agent	CMC or other listed agents	Carboxymethylcellulose sodium identified in labeling
Bulking agent	Mannitol and other listed agents	Mannitol identified in labeling
Buffer	Sodium phosphate and alternatives	Phosphate components identified in labeling
Dose strengths in claim 18	100, 200 and 400 mg/mL	300 mg and 400 mg dosage strengths
Crystal forms	Anhydrous or monohydrate, including named forms	Product-specific solid form requires regulatory and technical comparison

The overlap is strongest at the platform level. Literal infringement cannot be determined from public excipient disclosure alone. The claim requires particle size, freeze-dried structure, concentration and release performance. FDA labeling generally does not disclose every parameter needed for an infringement analysis.

When does U.S. Patent 7,807,680 lose exclusivity?

The patent issued on October 5, 2010. Its enforceable term depends on the earliest effective nonprovisional filing or priority date, patent-term adjustment, terminal disclaimers and any applicable patent-term extension. The patent is not a biologic patent and therefore does not receive a 12-year biologic exclusivity period.

The patent should be analyzed under the following timeline:

Event	Date or consequence
Patent grant	October 5, 2010
Standard U.S. utility term	20 years from the effective nonprovisional filing date
Patent-term adjustment	Must be checked in the USPTO patent record
Patent-term extension	Must be checked separately from FDA regulatory exclusivity
FDA product exclusivity	Separate from patent term
Generic entry	Depends on remaining listed patents, regulatory exclusivity, litigation and settlement terms

A patent’s expiration does not eliminate other patents protecting the same product. Long-acting aripiprazole products may have later-issued formulation, dosing, delivery-device, manufacturing or method-of-use patents. A freedom-to-operate review therefore cannot stop with U.S. Patent 7,807,680.

What is the Orange Book status of the patent?

The Orange Book, rather than the patent specification alone, determines whether the patent is listed against an approved drug application for Hatch-Waxman purposes. The relevant questions are:

Whether U.S. Patent 7,807,680 is listed for the relevant aripiprazole injectable NDA.
Whether the listing covers the drug substance, drug product or method of use.
Whether the listing has expired or been delisted.
Whether later patents remain listed.
Whether a generic ANDA applicant must certify under Paragraph IV.

The FDA Orange Book identifies patents submitted by NDA holders and does not independently decide patent validity or infringement [3]. A patent may be technically relevant to a product but absent from the current Orange Book listing. Conversely, an Orange Book-listed patent may cover a narrower method of use rather than the full formulation.

Are there Paragraph IV challenges to the patent?

A Paragraph IV certification alleges that an Orange Book-listed patent is invalid, unenforceable or will not be infringed by the proposed ANDA product. The existence of a Paragraph IV certification must be confirmed through the relevant FDA listing, ANDA litigation docket and statutory notices.

For a long-acting injectable, the regulatory pathway is more complex than for an immediate-release tablet. The applicant must address formulation sameness, sterile manufacturing, reconstitution, injection performance, particle size, release characteristics and clinical or comparative requirements. A 505(b)(2) applicant may pursue a different pathway from an ANDA applicant, particularly where the proposed product differs in formulation, device, dosing or clinical use.

A challenge to U.S. Patent 7,807,680 would likely focus on:

Whether the accused formulation is actually freeze-dried as a cake.
Whether the drug has the claimed mean particle size.
Whether the reconstituted suspension is homogeneous.
Whether the composition has the claimed concentration.
Whether the product releases drug for the claimed period.
Whether the patent is expired or otherwise unenforceable.
Whether prior art discloses the combination of micronized aripiprazole, suspending agent and lyophilized injectable depot.

Which companies are challenging long-acting aripiprazole exclusivity?

The relevant competitive field includes:

Generic injectable manufacturers pursuing an ANDA.
505(b)(2) developers pursuing alternative long-acting aripiprazole products.
Developers of ready-to-use suspensions, polymeric depots or microsphere systems.
Companies developing alternative crystal forms or particle-size distributions.
Manufacturers using different sterilization and milling processes.

An ANDA applicant seeking a product equivalent to Abilify Maintena faces a different risk profile from a 505(b)(2) applicant using a distinct depot technology. The former must address Orange Book certifications. The latter may avoid some listed claims but face clinical, CMC and formulation-development requirements.

No biosimilar pathway applies. Aripiprazole is a chemically synthesized small molecule, so competing products proceed through generic or alternative-drug-application pathways rather than the Public Health Service Act biosimilar framework.

How strong is the patent estate for the claimed formulation?

U.S. Patent 7,807,680 has meaningful technical breadth but several claim vulnerabilities.

Strengths

It combines composition, dosage form and pharmacokinetic performance.
Claims 1 and 22 provide relatively broad duration alternatives.
Claims 4-9 and 16-18 provide commercially concrete excipient and concentration combinations.
Claims 25-29 create process coverage in addition to product coverage.
Claims 10-15 and 21 protect selected solid forms.
The formulation closely tracks the technical requirements of a monthly injectable product.

Vulnerabilities

Mean particle size may require a defined measurement method and sampling protocol.
“Homogeneous suspension” may create claim-construction disputes.
Release-period limitations may be difficult to prove without clinical or validated release data.
Prior art may disclose micronized aripiprazole suspensions, lyophilization or depot injections separately.
Product-by-process claims may be limited if the resulting product is indistinguishable from products made through other processes.
The patent’s remaining enforceable term, if any, must be calculated from the official patent record.
Later patents may provide the principal commercial barrier even if this patent has expired.

What generic launch scenarios exist?

Scenario 1: Direct equivalent injectable

A direct equivalent uses a freeze-dried aripiprazole cake, CMC, mannitol, phosphate buffer, comparable particle size and monthly release. This product faces the highest risk under claims 1, 4, 6, 16, 18 and 36, as well as any later Orange Book-listed patents.

Scenario 2: Different excipient system

A product uses a different suspending agent, bulking agent or buffer. It may avoid narrower composition claims, but claims 1, 21 or 22 could still apply if the broad functional and structural limitations are met.

Scenario 3: Different solid form

A developer uses a crystal form outside Hydrate A or Anhydride Crystals B. Claims limited to those forms may be avoided. Claims reciting aripiprazole without the named form remain relevant.

Scenario 4: Non-lyophilized depot

A ready-to-use suspension, microsphere, implant or polymeric depot may avoid the freeze-dried-cake requirement. Its risk shifts to later formulation, delivery-system, manufacturing and method-of-use patents.

Scenario 5: Different manufacturing route

A product uses sterile micronization, spray drying or another particle-size process instead of wet ball milling. Claims 26, 27, 32 and 33 may be avoided, but the product claims remain potentially relevant.

What geographic coverage does the patent provide?

U.S. Patent 7,807,680 provides rights only in the United States. Parallel protection must be evaluated country by country through the related international and national-phase filings. Key jurisdictions for a long-acting aripiprazole product include:

European Patent Office member states.
Japan.
Canada.
Australia.
South Korea.
China.
Brazil.
Mexico.

Patent term, claim amendments, prosecution history, supplementary protection certificates, compulsory-license rules and litigation outcomes differ by jurisdiction. A U.S. expiration date does not establish freedom to operate in Europe or other markets.

What manufacturing and IP barriers remain after this patent?

The principal non-patent barriers are sterile injectable manufacturing, aseptic processing, lyophilization capacity, particle-size control, suspension uniformity, reconstitution time, needleability and long-term stability. These requirements can delay entry even after a patent expires.

The most relevant IP barriers are likely to include:

Later formulation patents.
Monthly or extended dosing patents.
Injection-device patents.
Reconstitution-system patents.
Manufacturing and sterilization patents.
Crystal-form and particle-size patents.
Method-of-use patents covering schizophrenia, bipolar disorder or maintenance treatment.
Regulatory exclusivity associated with the approved injectable product.

Key Takeaways

U.S. Patent 7,807,680 targets a freeze-dried, sterile, micronized aripiprazole injectable suspension.
Its central commercial combination is aripiprazole, carboxymethylcellulose, mannitol, phosphate buffer and lyophilization.
Claims 1, 21 and 22 establish the broadest formulation framework.
Claims 18 and 36 provide the most commercially specific composition coverage.
Claims 25-29 and 31-34 create separate process and product-by-process exposure.
The patent expressly covers monohydrate and selected anhydrous crystal forms.
Abilify Maintena has substantial technical overlap with the claimed formulation architecture, but public labeling alone does not establish infringement.
No biosimilar pathway applies because aripiprazole is a small molecule.
Generic entry depends on the patent’s verified term, current Orange Book listings, later patents, regulatory pathway and any Paragraph IV litigation or settlement.
Geographic freedom to operate requires separate national patent reviews.

FAQs About U.S. Patent 7,807,680

Does U.S. Patent 7,807,680 cover oral aripiprazole tablets?

No. The claims require a sterile freeze-dried formulation that is reconstituted into an injectable suspension. Oral tablets and ordinary oral solid formulations fall outside the stated claim scope.

Does the patent cover every long-acting aripiprazole injection?

No. The claims are directed to specific structural, compositional, processing and release characteristics. A different depot technology may avoid this patent while remaining subject to other patents.

Is 400 mg/mL aripiprazole specifically claimed?

Yes. Claim 18 expressly identifies a 400 mg/mL formulation containing carboxymethylcellulose, mannitol, sodium phosphate and pH adjustment with sodium hydroxide.

Can a product avoid the patent by using a particle size above 10 microns?

Potentially, with respect to claims requiring a mean particle size of 1-10 microns. The result depends on the full claim set, measurement method, doctrine of equivalents and any other applicable patent.

Does patent expiration automatically permit a generic launch?

No. Launch timing can remain restricted by later patents, Orange Book listings, regulatory exclusivity, injunctions, settlement agreements, manufacturing requirements and unresolved patent litigation.

References

United States Patent and Trademark Office. (2010). U.S. Patent No. 7,807,680, sterile freeze-dried controlled release aripiprazole formulations. https://patents.google.com/patent/US7807680B2/en
U.S. Food and Drug Administration. (2024). Abilify Maintena prescribing information. Otsuka Pharmaceutical Co., Ltd. https://www.accessdata.fda.gov/drugsatfda_docs/label/
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/approved-drug-products-therapeutic-equivalence-evaluations-orange-book
U.S. Patent and Trademark Office. (2024). Patent term adjustment and patent term calculation resources. https://www.uspto.gov/patents/laws/patent-term-calculator
U.S. Food and Drug Administration. (2024). Hatch-Waxman amendments and ANDA patent certifications. https://www.fda.gov/drugs/abbreviated-new-drug-application-anda/abbreviated-new-drug-application-anda-forms-and-submissions

Country	Patent Number	Estimated Expiration	Supplementary Protection Certificate	SPC Country	SPC Expiration
European Patent Office	1675573	⤷ Start Trial	CA 2014 00026	Denmark	⤷ Start Trial
European Patent Office	1675573	⤷ Start Trial	C300669	Netherlands	⤷ Start Trial
European Patent Office	1675573	⤷ Start Trial	92427	Luxembourg	⤷ Start Trial
European Patent Office	1675573	⤷ Start Trial	PA2014020	Lithuania	⤷ Start Trial
European Patent Office	1675573	⤷ Start Trial	C01675573/01	Switzerland	⤷ Start Trial
European Patent Office	1675573	⤷ Start Trial	300669	Netherlands	⤷ Start Trial
European Patent Office	1675573	⤷ Start Trial	32/2014	Austria	⤷ Start Trial
>Country	>Patent Number	>Estimated Expiration	>Supplementary Protection Certificate	>SPC Country	>SPC Expiration

Details for Patent: 7,807,680

Summary for Patent: 7,807,680