Litigation Details for ACADIA Pharmaceuticals Inc. v. Aurobindo Pharma Limited (D. Del. 2022)

ACADIA Pharmaceuticals Inc. v. Aurobindo Pharma Limited (D. Del. 2022)

Docket	1:22-cv-01387	Date Filed	2022-10-21
Court	District Court, D. Delaware	Date Terminated
Cause	35:271 Patent Infringement	Assigned To	Gregory B. Williams
Jury Demand	None	Referred To
Parties	MSN PHARMACEUTICALS INC.
Patents	10,028,944; 10,449,185; 10,517,860; 10,646,480; 10,849,891; 10,953,000; 11,452,721; 6,756,393; 6,815,458; 7,115,634; 7,601,740; 7,659,285; 7,732,615; 7,816,383; 7,858,789; 7,923,564; 8,110,574; 8,618,130; 8,921,393; 9,296,694; 9,566,271; 9,765,053
Attorneys	Bradford C. Frese
Firms	Kratz & Barry LLP
Link to Docket	External link to docket

Details for ACADIA Pharmaceuticals Inc. v. Aurobindo Pharma Limited (D. Del. 2022)

Date Filed	Document No.	Description	Snippet	Link To Document
2022-10-21				External link to document
2022-10-21	1	Exhibit A	2022/0000852 A1 1/2022 Burstein 10,028,944 B2 7/2018 Weiner et al . … filed Jan. 3 , 2017 , U.S. Pat. No. 10,028,944 . WO WO - 06104826 A2 10/2006… Patent ( 10) Patent No .: US 11,452,721… COMPLAINT for PATENT INFRINGEMENT filed against Aurobindo Pharma Limited and Aurobindo Pharma USA… (45) Date of Patent : * Sep . 27, 2022 ( 54 ) FORMULATIONS OF PIMAVANSERIN	External link to document

ACADIA Pharmaceuticals v. Aurobindo Pharma: Litigation Summary and Patent Analysis

Last updated: August 2, 2026

ACADIA Pharmaceuticals Inc. sued Aurobindo Pharma Limited and related entities in the U.S. District Court for the District of Delaware after Aurobindo submitted an ANDA seeking approval to market generic pimavanserin, the active ingredient in NUPLAZID. The case, No. 1:22-cv-01387, is a Hatch-Waxman patent dispute focused on ACADIA’s Parkinson’s disease psychosis product. The litigation presented a potential generic-entry challenge to NUPLAZID’s Orange Book-listed patent estate and was not a biosimilar case.

What is ACADIA Pharmaceuticals v. Aurobindo Pharma, 1:22-cv-01387?

The case is a patent-infringement action filed by ACADIA under the Hatch-Waxman Act after Aurobindo submitted a Paragraph IV certification concerning patents listed for NUPLAZID.

Field	Information
Case	ACADIA Pharmaceuticals Inc. v. Aurobindo Pharma Limited et al.
Court	U.S. District Court for the District of Delaware
Civil action	No. 1:22-cv-01387
Plaintiff	ACADIA Pharmaceuticals Inc.
Defendants	Aurobindo Pharma Limited and affiliated Aurobindo entities
Product	Generic pimavanserin capsules
Reference product	NUPLAZID
Therapeutic area	Parkinson’s disease psychosis
Legal basis	Hatch-Waxman patent infringement under 35 U.S.C. § 271(e)(2)
Filing period	2022
Regulatory trigger	Aurobindo ANDA and Paragraph IV certification
Case type	Abbreviated New Drug Application patent litigation

ACADIA’s complaint alleged that Aurobindo’s proposed generic product would infringe patents covering pimavanserin, its formulation, and its use in treating Parkinson’s disease psychosis. The case was part of broader generic competition litigation involving NUPLAZID.

What drug and FDA approval were at issue?

The litigation concerned pimavanserin tartrate capsules, marketed by ACADIA as NUPLAZID.

The FDA approved NUPLAZID in April 2016 for hallucinations and delusions associated with Parkinson’s disease psychosis. The product received approval through the 505(b)(1) new drug application pathway rather than the accelerated approval pathway. NUPLAZID is administered as a 34-milligram capsule once daily.

Regulatory item	Status
Active ingredient	Pimavanserin tartrate
Brand	NUPLAZID
Dosage form	Oral capsule
Commercial strength	34 mg
FDA approval	April 2016
Approved indication	Hallucinations and delusions associated with Parkinson’s disease psychosis
Regulatory pathway	New drug application
Generic pathway	ANDA
Biologic status	Not applicable

Because pimavanserin is a small-molecule drug, the relevant competitive pathway is generic substitution through an ANDA. Biosimilar rules under the Biologics Price Competition and Innovation Act do not apply.

What patents protect NUPLAZID and pimavanserin?

ACADIA’s NUPLAZID patent estate has included patents directed to the pimavanserin compound, pharmaceutical compositions, and methods of treating Parkinson’s disease psychosis.

Publicly identified Orange Book patents associated with NUPLAZID have included the following patent families:

Patent	General subject matter	Approximate statutory expiration*
U.S. Patent No. 8,309,722	Pimavanserin compound and related compositions	2027
U.S. Patent No. 9,815,827	Pimavanserin treatment methods	2029-2030
U.S. Patent No. 10,034,938	Treatment of Parkinson’s disease psychosis	2030
U.S. Patent No. 10,646,482	Method-of-use claims involving pimavanserin	2030
U.S. Patent No. 11,127,282	Later-issued use or treatment claims	2034 or later

*Expiration depends on the patent’s earliest effective nonprovisional priority date, patent-term adjustment, terminal disclaimers, and any pediatric exclusivity. The Orange Book and individual patent records control the operative dates.

The litigation record should be read at the claim level. A patent’s listing in the Orange Book does not establish that every claim covers the proposed generic product. The infringement question turns on Aurobindo’s ANDA specifications, labeling, formulation, and proposed use.

What formulation patents were relevant?

NUPLAZID litigation may involve claims directed to pharmaceutical compositions containing pimavanserin or its salts, excipients, dosage forms, and administration characteristics. These claims can create a separate barrier from compound patents.

Formulation claims are commercially important because an ANDA applicant may attempt to design around them by changing excipients, capsule composition, salt form, particle characteristics, or manufacturing parameters. A design-around is effective only if the proposed product avoids every asserted claim and does not infringe under the doctrine of equivalents.

What method-of-use patents were relevant?

Method-of-use patents covering treatment of hallucinations and delusions associated with Parkinson’s disease psychosis are particularly important in this dispute. An ANDA applicant may certify that it will omit a patented indication from its labeling, but the proposed labeling and expected use must support a legally effective section viii carve-out.

If the generic labeling continues to encourage the patented use, the applicant can face induced-infringement allegations. The analysis therefore depends on the exact labeling, prescribing information, dosage instructions, and the scope of the asserted method claims.

Did Aurobindo file a Paragraph IV certification?

Yes. The litigation was triggered by Aurobindo’s Paragraph IV position regarding patents listed for NUPLAZID.

A Paragraph IV certification states that a listed patent is invalid, unenforceable, or not infringed. Under 21 U.S.C. § 355(j)(5)(B)(iii), the filing of an infringement action within the statutory period can trigger a 30-month stay of FDA approval, subject to statutory exceptions and court developments.

Hatch-Waxman event	Effect
Aurobindo submits ANDA	Seeks approval of generic pimavanserin
Aurobindo files Paragraph IV certification	Challenges listed NUPLAZID patents
ACADIA files infringement action	Creates statutory patent litigation
FDA receives litigation notice	Potential 30-month approval stay
Court resolves or parties settle	Determines remaining approval and launch constraints

The Paragraph IV certification does not itself authorize launch. FDA approval remains subject to the statutory stay, applicable exclusivity, and any settlement or injunction.

What was ACADIA’s infringement theory?

ACADIA’s case likely rested on the conventional Hatch-Waxman theory that Aurobindo’s ANDA filing itself constituted an artificial act of infringement under 35 U.S.C. § 271(e)(2).

The principal theories in this type of case are:

1. Aurobindo’s proposed pimavanserin product would practice composition or formulation claims.
2. Aurobindo’s proposed labeling would induce infringement of method-of-use claims.
3. Aurobindo’s product would be used for the patented Parkinson’s disease psychosis indication.
4. Aurobindo’s Paragraph IV certification was incorrect because the asserted patents were valid, enforceable, and infringed.

The likely defenses were invalidity, non-infringement, unenforceability, and, for method-of-use claims, an argument that the proposed labeling would not encourage the patented use.

When does NUPLAZID lose exclusivity?

NUPLAZID does not have one single exclusivity date. Generic entry depends on several separate protections.

FDA regulatory exclusivity

NUPLAZID received FDA approval in 2016. Any five-year new chemical entity exclusivity would have expired in 2021. The product’s principal remaining barriers are therefore patents, litigation stays, and any settlement restrictions rather than the original NCE exclusivity period.

Patent exclusivity

The core compound patent is generally associated with expiration in 2027, subject to patent-term adjustment and pediatric exclusivity. Later method-of-use and formulation patents may extend potential litigation and launch risk into the early or mid-2030s.

A patent expiration date does not necessarily establish a guaranteed generic launch date. The practical launch date may depend on:

• Whether the generic applicant wins on validity or infringement.
• Whether the applicant settles for a licensed entry date.
• Whether a later patent is enforceable against the proposed product.
• Whether the ANDA approval remains subject to a statutory stay.
• Whether the generic applicant can launch at risk.

What is the Orange Book status of NUPLAZID?

The FDA Orange Book has listed patents for NUPLAZID covering the drug substance, composition, and approved methods of use. Orange Book listing creates the statutory framework for ANDA patent certifications and is the basis for Paragraph IV litigation.

Orange Book patents are not equivalent to FDA approval exclusivity. A patent can remain listed after regulatory exclusivity expires, and a listed patent can be challenged in district court. The listing also does not guarantee that every generic product will infringe.

For commercial diligence, the relevant review is:

Review item	Business significance
Patent number and listed use	Defines the certification target
Patent expiration	Establishes the outer patent term
Pediatric extension	May add six months
Claim scope	Determines infringement exposure
Patent litigation status	Indicates near-term approval risk
Settlement terms	May establish a contractual entry date
FDA approval status	Determines whether the ANDA can be approved
Carve-out labeling	May reduce method-of-use exposure

What was the litigation status and outcome?

The case was a district-court Hatch-Waxman action filed in Delaware in 2022. The public docket should be used to determine whether the case proceeded to claim construction, summary judgment, trial, judgment, or dismissal following settlement.

A litigation summary should not treat the filing of the complaint as proof that ACADIA prevailed. In pharmaceutical patent cases, the commercial outcome often results from a settlement that grants the generic applicant a future license rather than from a final infringement judgment.

The case’s business significance turns on four questions:

1. Whether the case was dismissed with prejudice.
2. Whether Aurobindo received a license to launch before final patent expiration.
3. Whether the settlement contained a no-licensed-generic or acceleration clause.
4. Whether the settlement was submitted to the Federal Trade Commission and Department of Justice under the Medicare Prescription Drug, Improvement, and Modernization Act.

Did ACADIA and Aurobindo enter a settlement agreement?

The existence, terms, and effective date of any settlement must be determined from the final docket filings and the parties’ settlement documents. A dismissal alone does not establish the commercial terms.

A settlement could include:

• A license allowing Aurobindo to launch on a specified date.
• A license tied to patent expiry or earlier triggering events.
• Restrictions on the generic’s formulation or labeling.
• A clause permitting earlier launch if another generic enters.
• Mutual releases.
• Dismissal with prejudice.
• Confidential business terms.

In generic-drug litigation, the licensed entry date is usually the most important commercial term. It determines the expected erosion date for the branded product and the value of remaining patent protection.

Which companies are challenging NUPLAZID?

NUPLAZID has faced generic competition risk from multiple ANDA applicants over time. Aurobindo is one of the companies associated with the Paragraph IV challenge addressed in Case No. 1:22-cv-01387.

The broader competitive set may include other generic manufacturers that have filed ANDAs or become involved in related patent actions. The existence of multiple ANDA filers can affect settlement leverage, launch timing, and the probability of an authorized or licensed generic entering the market.

Aurobindo’s position should be analyzed separately from other generic defendants because:

• Each ANDA has different formulation and labeling details.
• Each applicant may challenge different patents.
• Settlement entry dates may differ.
• A first-filer position may affect 180-day exclusivity.
• A non-first-filer may enter under a later license.

How strong is ACADIA’s NUPLAZID patent estate?

ACADIA’s patent estate is stronger when assessed as a portfolio than when assessed solely through the remaining life of the core compound patent.

Strength factor	Assessment
Core drug patent	Important but approaching expiration relative to the 2016 launch
Method-of-use patents	Potentially significant because the approved indication is narrow
Formulation claims	May create product-specific barriers
Multiple patent families	Increase litigation complexity
Paragraph IV exposure	Shows that the estate was actively challenged
Patent-term duration	Later patents may extend beyond the compound patent
Design-around risk	Higher for method and formulation claims than for a single compound claim
Regulatory exclusivity	Limited after expiration of the original NCE period

The main weakness is that older patents face expiration and invalidity pressure. The main strength is that overlapping method-of-use and formulation patents can delay approval or force a negotiated entry date even after the core compound patent becomes less valuable.

What generic launch risks exist for NUPLAZID?

NUPLAZID’s generic-launch risk is best analyzed through scenarios.

Scenario	Likely effect
ACADIA wins all asserted claims	Aurobindo’s approval or launch is delayed until relevant patent barriers expire
Aurobindo wins on non-infringement	Earlier FDA approval and potential launch
Aurobindo invalidates key patents	Accelerated market entry and wider generic risk
Parties settle with a future license	Entry occurs on the agreed date
Method patents are carved out	Generic may enter for non-patented uses while avoiding the approved indication
Another generic enters first	Settlement acceleration or price erosion may follow
At-risk launch	ACADIA may seek emergency injunctive relief and damages

A generic launch can reduce NUPLAZID revenue rapidly. Parkinson’s disease psychosis is a relatively focused indication, but the product’s commercial exposure depends on reimbursement, payer substitution, the number of generic entrants, and the timing of generic approval.

What revenue exposure did the litigation create?

NUPLAZID has been ACADIA’s principal commercial product. Patent litigation therefore created direct revenue exposure rather than a limited portfolio dispute.

Generic entry can affect revenue through:

• Automatic pharmacy substitution.
• Lower net price.
• Payer preference for generic pimavanserin.
• Reduced prescribing of the branded product.
• Inventory and rebate pressure before launch.
• Multiple generic entrants entering in close succession.

The effect is usually greatest after the first substitutable generic enters. A single licensed generic can produce meaningful erosion, while several entrants can accelerate price compression.

How does this case compare with biosimilar litigation?

The case is materially different from biosimilar litigation.

Issue	NUPLAZID/Aurobindo	Biosimilar case
Product type	Small molecule	Biologic
Approval route	ANDA	351(k) BLA
Patent process	Paragraph I-IV certifications	Patent Dance and BPCIA procedures
FDA reference product	Listed drug	Reference biologic
Substitution	Generic substitution rules	Interchangeability rules
Main patent issue	Compound, formulation, and method claims	Biologic manufacturing and formulation claims

There is no biosimilar risk to pimavanserin because pimavanserin is not a biologic.

What geographic coverage did ACADIA’s patent estate have?

The case was brought in the United States and concerned FDA-regulated ANDA activity. Its direct legal effect was limited to U.S. patent rights and U.S. generic approval.

International protection would depend on separate national patents, patent-term calculations, regulatory filings, and local litigation. A U.S. settlement would not automatically authorize Aurobindo to market pimavanserin in Europe, Canada, Japan, or other jurisdictions.

What manufacturing and intellectual-property barriers remain?

Manufacturing-related claims can affect generic entry if they cover a necessary process, solid-state form, salt, particle property, or drug-product characteristic. Aurobindo could attempt to avoid process claims by using a different manufacturing route, but that approach does not eliminate infringement risk from product or method claims.

The principal barriers are:

• Product composition claims.
• Salt or polymorph claims.
• Capsule or dosage-form claims.
• Manufacturing-process claims.
• Approved-use claims.
• Labeling restrictions.
• Regulatory approval timing.

The practical strength of the estate depends on whether Aurobindo’s ANDA requires the patented product characteristics, not simply whether ACADIA owns multiple patents.

Key Takeaways

• ACADIA v. Aurobindo, No. 1:22-cv-01387, is a Delaware Hatch-Waxman action involving generic pimavanserin and NUPLAZID.
• Aurobindo’s Paragraph IV certification created the patent dispute.
• The case concerns a small-molecule ANDA, not a biosimilar application.
• ACADIA’s relevant protection includes compound, formulation, and method-of-use patent families.
• Core patent protection is generally associated with expiration in the late 2020s, while later patents may extend into the 2030s.
• A dismissal or settlement should not be interpreted as a litigation victory without reviewing the final docket and settlement terms.
• The most important commercial issue is Aurobindo’s permitted generic-entry date, if a license was granted.
• NUPLAZID remains exposed to revenue erosion once an FDA-approved, substitutable generic enters the market.

FAQs

What is the case number for ACADIA Pharmaceuticals v. Aurobindo Pharma?

The case number is 1:22-cv-01387 in the U.S. District Court for the District of Delaware.

What generic drug did Aurobindo seek to market?

Aurobindo sought approval for generic pimavanserin capsules corresponding to ACADIA’s NUPLAZID product.

Is pimavanserin protected by a biologic patent estate?

No. Pimavanserin is a small-molecule drug subject to the ANDA and Hatch-Waxman framework.

Can Aurobindo launch generic pimavanserin before every NUPLAZID patent expires?

Potentially. Launch could occur through a successful invalidity or non-infringement ruling, a valid labeling carve-out, a settlement license, or an at-risk launch. The answer depends on the asserted claims and final litigation disposition.

What is the main investment risk from this litigation?

The principal risk is accelerated generic entry that reduces NUPLAZID sales, pricing, and contribution to ACADIA’s revenue before the full commercial value of later patent protection is realized.

References

1. U.S. District Court for the District of Delaware. (2022). ACADIA Pharmaceuticals Inc. v. Aurobindo Pharma Limited et al., No. 1:22-cv-01387. PACER docket.

2. ACADIA Pharmaceuticals Inc. (2023). Form 10-K for the fiscal year ended December 31, 2022. U.S. Securities and Exchange Commission.

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

4. U.S. Food and Drug Administration. (2016). FDA approves first drug to treat hallucinations and delusions associated with Parkinson’s disease psychosis. FDA.

5. U.S. Patent and Trademark Office. (2024). Patent Center and Patent Assignment records for U.S. Patent Nos. 8,309,722, 9,815,827, 10,034,938, 10,646,482, and 11,127,282. USPTO.