American Regent v. Amneal: Selenious Acid ANDA Dispute Resolved by Consent Judgment in 57 Days
American Regent, Inc. filed suit against Amneal Pharmaceuticals in the District of New Jersey over two patents covering its selenious acid injection product (600 mcg Selenium/10 mL). The parties reached a negotiated consent judgment — including a permanent injunction against Amneal — in just 57 days, one of the fastest resolutions in recent Hatch-Waxman ANDA litigation.
Swift Hatch-Waxman Consent Judgment Locks Out Amneal’s Generic Selenium Injection
American Regent, Inc. (ARI) filed this Hatch-Waxman patent infringement action in the District of New Jersey on December 30, 2024, asserting two patents — US11998565B2 and US12150957B2 — against Amneal Pharmaceuticals’ abbreviated new drug application (ANDA No. 219069) for a generic selenious acid injection (600 mcg Selenium/10 mL). ARI’s branded product delivers intravenous selenium, a critical trace element used in parenteral nutrition, and the asserted patents protect the formulation and methods associated with that product.
The case concluded on February 25, 2025 — just 57 days after filing — through a consent judgment entered by the District Court. The consent judgment enjoins Amneal and its affiliates from making, using, selling, offering to sell, importing, or distributing the ANDA product in the United States unless specifically authorized by ARI or by 35 U.S.C. § 271(e)(1). Critically, the FDA retains authority to grant final approval to Amneal’s ANDA, and Amneal may maintain its Paragraph IV certification — signalling that a licensing arrangement, rather than outright capitulation, likely underlies the settlement agreement.
The 57-day timeline suggests the parties entered negotiations almost immediately after service, consistent with a pre-existing licensing framework or rapid commercial resolution rather than hard-fought litigation. The underlying settlement agreement is not public, so the specific royalty terms, licensed entry date, or any market exclusivity provisions remain unknown from the public record. What is clear is that ARI has secured court-enforced protection for both patents across Amneal’s entire ANDA product line, with the court retaining jurisdiction to supervise ongoing compliance.
Filing to Consent Judgment in 57 days
57-day resolution — well below the typical 12–30 month Hatch-Waxman litigation window
Consent judgment with injunction: what the resolution means for both parties
Consent judgment is a court order, not just a settlement
A consent judgment is entered by the court and carries the full force of a judicial order. Unlike a private settlement agreement, it is directly enforceable through contempt proceedings. Here, the District of New Jersey retains jurisdiction to supervise compliance, giving ARI a powerful enforcement tool if Amneal launches outside the agreed terms. The underlying settlement agreement governs the commercial details, but the injunction is the court-backed mechanism.
Court-enforceable injunctionARI secures injunction over both patents without trial risk
American Regent obtained a permanent injunction covering both US11998565B2 and US12150957B2 against Amneal’s ANDA product — without the cost or uncertainty of a full Hatch-Waxman trial. The dismissal is without prejudice, preserving ARI’s ability to re-file if Amneal were to breach the settlement agreement. ARI’s selenium injection franchise is protected while the FDA process for Amneal’s ANDA continues, suggesting a negotiated licensed-entry date may govern future market access.
Dual-patent injunction securedAmneal enjoined but ANDA and Paragraph IV certification preserved
Amneal cannot launch its generic selenious acid injection in the U.S. without ARI’s authorisation, but critically retains its ANDA approval pathway and Paragraph IV certification rights. This is consistent with a negotiated licensed-entry arrangement — Amneal likely agreed to a future market entry date or royalty structure rather than abandoning its generic entirely. The without-prejudice dismissal also means Amneal faces no res judicata bar on the underlying patent validity questions.
ANDA preserved; launch deferredRapid resolution pattern signals ARI’s Hatch-Waxman enforcement posture
A 57-day consent judgment in an ANDA case is unusually fast and suggests ARI entered the litigation with a clear licensing strategy rather than seeking a merits verdict. For competing generic manufacturers watching this space, the dual-patent assertion across formulation and method claims — combined with rapid enforcement — raises the cost of any non-licensed ANDA challenge to ARI’s selenium franchise. Other ANDA filers for selenious acid products should anticipate similar early-stage enforcement action.
Early enforcement precedent setFull party and counsel information
| Role | Name | Type | Detail |
|---|---|---|---|
| Plaintiff | American Regent, Inc. | Company | Pharmaceutical company — holder of US11998565B2 and US12150957B2 (selenious acid injection)Search in Eureka ↗ |
| Defendant | Amneal Pharmaceuticals, Inc. | Company | Generic pharmaceutical manufacturer seeking ANDA approval for selenious acid injection, USPSearch in Eureka ↗ |
| Plaintiff counsel | Charles H. Chevalier | Attorney | Counsel for American Regent, Inc.Search in Eureka ↗ |
| Plaintiff counsel | Christine A. Gaddis | Attorney | Counsel for American Regent, Inc.Search in Eureka ↗ |
| Plaintiff counsel | Dennies Varughese | Attorney | Counsel for American Regent, Inc.Search in Eureka ↗ |
| Plaintiff law firm | Gibbons PC | Law Firm | Representing American Regent, Inc.Search in Eureka ↗ |
| Plaintiff law firm | Sterne Kessler Goldstein & Fox | Law Firm | Representing American Regent, Inc.Search in Eureka ↗ |
| Presiding judge | Judge N/A | Judge | New Jersey District CourtSearch in Eureka ↗ |
Official order — verbatim text
The consent judgment language is precise in scope: Amneal and all affiliates are enjoined from any commercial act involving ANDA No. 219069’s product in the U.S., but the FDA approval pathway and Paragraph IV certification are explicitly preserved. This dual construct — injunction plus preserved ANDA — is the hallmark of a Hatch-Waxman licensed-entry settlement. The dismissal of all claims ‘without prejudice and without costs’ means neither party acknowledged liability, and ARI retains the right to reassert infringement if the private settlement agreement is breached.
US11998565B2 & US12150957B2 — Selenious Acid Injection Formulation Patents
US11998565B2 and US12150957B2 both protect aspects of ARI’s selenious acid injection product — a sterile intravenous formulation delivering 600 mcg of selenium per 10 mL (60 mcg/mL), used in parenteral nutrition regimens. The applications (US18/124391 and US18/672876) are relatively recent filings, suggesting ARI has been actively building and refreshing its patent portfolio around this established trace element therapy. Selenium deficiency in critically ill and long-term parenteral nutrition patients is a documented clinical concern, giving these formulations significant therapeutic and commercial value.
From a competitive intelligence standpoint, ARI’s dual-patent strategy — covering both the formulation and likely related method claims — creates overlapping protection that complicates any design-around effort by generic manufacturers. The rapid enforcement against Amneal’s ANDA demonstrates that ARI treats these patents as commercially active enforcement assets, not defensive filings. Any company with a pending or planned ANDA for selenious acid injectable products should treat both patents as live blocking assets requiring FTO clearance before committing to development expenditure.
Should you run an FTO analysis against US11998565B2 and US12150957B2?
If your organisation is developing, manufacturing, or seeking ANDA approval for any selenious acid injection product — or any parenteral trace element formulation in the selenium category — both US11998565B2 and US12150957B2 should be assessed as part of your freedom-to-operate review. ARI has demonstrated a willingness to file suit rapidly and enforce both patents simultaneously. The scope of the consent judgment covers making, using, selling, offering for sale, importing, and distribution, meaning the risk window extends beyond U.S. commercial launch.
PatSnap Eureka’s FTO Search Agent can map the claim scope of both patents against your product specifications, identify prior art that may bear on validity, and surface related ARI portfolio filings that could present additional risk vectors. Eureka also tracks ANDA litigation dockets in real time, so your team receives early signals of enforcement activity before it affects your product pipeline. Run your FTO analysis now to inform go/no-go decisions on selenious acid development programmes.
Run a freedom-to-operate analysis on US12150957B2 to assess your product’s exposure
Run FTO in Eureka →Similar Hatch-Waxman ANDA Cases Involving Parenteral Nutrition Patents in D.N.J.
Cases involving ANDA challenges to parenteral nutrition and injectable pharmaceutical patents in the District of New Jersey with consent judgment or early settlement outcomes.
Related patent case — similar technology
Comparable case in the same technology domain. Patent holder and defendant reached resolution after proceedings.
SettledRelated infringement action — same court
Comparable ARI’s Selenious Acid product (eq. 600 mcg Selenium/10 mL (eq. 60 mcg Selenium/mL))-adjacent infringement action. Patent enforcement dynamics analysed in depth.
Active · District CourtRelated invalidity challenge — appellate outcome
Combined invalidity and infringement action in the same technology space. Decided after substantive proceedings.
DecidedAmerican Regent, Inc.’s broader IP enforcement history
American Regent, Inc.’s full litigation history covering prior enforcement, licensing activity, and inter partes review proceedings.
Portfolio viewWhat this case signals for the parenteral nutrition IP landscape
ARI’s swift enforcement of two selenium injection patents illustrates how branded pharma can use Hatch-Waxman litigation as a rapid licensing lever.
Dual-patent ANDA filings enable broader injunctive coverage with less trial risk
By asserting both a formulation patent (US11998565) and a related method/use patent (US12150957) together, ARI created a wider infringement net. Even if one patent faced validity challenges, Amneal would need to design around both — a significant barrier that likely accelerated the consent judgment outcome.
Consent judgment with retained jurisdiction is stronger than a private settlement
ARI’s insistence on a court-entered consent judgment — rather than a simple voluntary dismissal — means any breach by Amneal is immediately actionable as contempt. For IP teams monitoring this space, this enforcement structure is increasingly common in pharmaceutical ANDA disputes and should be factored into generic launch risk assessments.
Preserved ANDA pathway suggests a licensed-entry date was the real deal point
The explicit carve-out allowing Amneal to maintain FDA approval and its Paragraph IV certification is a strong indicator that the private settlement agreement includes a negotiated future launch date. Generic entrants in the selenium IV space should monitor the ANDA status and any 180-day exclusivity implications carefully — a licensed Amneal launch could trigger exclusivity timelines affecting other ANDA applicants.
57-day resolution benchmarks ARI’s litigation-to-license conversion rate
ARI’s ability to convert a patent suit into a consent judgment in under two months suggests an experienced enforcement playbook. Companies with competing products or pending ANDAs in the parenteral trace element space should conduct FTO analysis against both US11998565B2 and US12150957B2 before committing to development spend — ARI appears prepared to act quickly.
American v Amneal — key questions answered
The case was resolved by consent judgment entered February 24, 2025 — 57 days after filing. Amneal and its affiliates are permanently enjoined from making, using, selling, or importing their selenious acid ANDA product (ANDA No. 219069) without ARI’s authorisation. All claims were dismissed without prejudice and without costs to either party.
ARI asserted US11998565B2 (application US18/124391) and US12150957B2 (application US18/672876). Both patents relate to ARI’s selenious acid injection product delivering 600 mcg of selenium per 10 mL, used in parenteral nutrition. The consent judgment refers to these collectively as the ‘Licensed ARI Patents.’
Yes. The consent judgment explicitly states that nothing in the order precludes the FDA from granting final approval to Amneal’s ANDA No. 219069, and Amneal retains the right to file, modify, or maintain a Paragraph IV certification. This suggests the underlying settlement agreement likely includes a negotiated future launch date or licensing terms, though those details are not public.
Dismissal without prejudice means ARI retains the right to re-file patent infringement claims against Amneal in the future — for example, if Amneal breaches the private settlement agreement. It also means Amneal faces no res judicata bar on patent validity issues. Neither party admitted liability, and no costs or attorneys’ fees were awarded to either side.
A 57-day resolution is unusually fast for ANDA patent litigation, which typically spans one to three years. The speed suggests the parties likely had pre-existing licensing discussions or a pre-negotiated framework before or shortly after filing. The structure of the consent judgment — with a preserved ANDA pathway and Paragraph IV certification — is consistent with a licensed-entry deal rather than a full capitulation by Amneal.
Stay ahead of parenteral pharma patent enforcement — run your FTO now
ARI’s 57-day enforcement playbook signals active monitoring of the selenious acid ANDA space. Use PatSnap Eureka to screen US11998565B2 and US12150957B2 against your pipeline and track new enforcement actions before they affect your launch timeline.
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