UCB Pharma v. Prinston Pharmaceutical: Briviact® Patent Consent Judgment
UCB Pharma GmbH and UCB Biopharma SRL brought an ANDA infringement action against Prinston Pharmaceutical and its Chinese parent Zhejiang Huahai Pharmaceutical over US6911461, the patent underpinning Briviact® brivaracetam epilepsy tablets. The case resolved in 371 days via a negotiated consent judgment that permanently enjoins Prinston from commercialising its generic version in the United States.
ANDA challenge to Briviact® ends with injunction barring Prinston’s generic
On 8 February 2024, UCB Pharma GmbH and UCB Biopharma SRL filed suit in the Delaware District Court against Prinston Pharmaceutical Inc. and its parent Zhejiang Huahai Pharmaceutical Co., Ltd., alleging infringement of US Patent No. 6,911,461 — a composition patent covering Briviact® brivaracetam tablets in 10 mg, 25 mg, 50 mg, 75 mg, and 100 mg strengths. The trigger was Prinston’s filing of Abbreviated New Drug Application No. 218573, a classic Paragraph IV ANDA challenge that requires the innovator to litigate or concede market entry rights within prescribed Hatch-Waxman windows.
The action closed on 13 February 2025 via a Consent Judgment and stipulated injunction entered by Judge Colm F. Connolly. Under its terms, Prinston and all its affiliates, successors, and assigns are permanently enjoined from making, using, selling, offering to sell, importing, or distributing the Prinston Products in the United States unless specifically authorised under the accompanying Settlement Agreement. All claims and affirmative defenses were dismissed without prejudice and without costs to either side, a structure that is legally distinct from a full merits adjudication but carries immediate and enforceable commercial consequences through the injunction.
A 371-day resolution suggests UCB moved decisively — possibly leveraging the automatic 30-month stay of ANDA approval under Hatch-Waxman to negotiate from a position of strength before trial costs mounted. The public record does not disclose whether any authorised generic launch date or royalty arrangement was agreed in the underlying Settlement Agreement, which remains confidential. What is clear is that Prinston’s US market entry is blocked unless UCB later grants explicit authorisation, making the patent’s remaining term commercially significant for both the originator and any future generic filer.
Filing to Consent Judgment in 371 days
371-day resolution — faster than the typical 2–3 year ANDA Hatch-Waxman trial timeline
Consent judgment with injunction: what the resolution means for both parties
Consent judgment is enforceable as a court order, not merely a contract
A consent judgment combines the binding force of a court decree with privately negotiated settlement terms. Because Judge Connolly entered the judgment and injunction on the docket, UCB can seek contempt proceedings if Prinston breaches the injunction — enforcement is through the court, not just breach-of-contract litigation. The court explicitly retained jurisdiction to supervise compliance. All claims were dismissed without prejudice, preserving each party’s theoretical ability to re-litigate underlying issues if the Settlement Agreement is later breached.
Court-enforceable injunctionUCB secures US market exclusivity for Briviact® without going to trial
The consent judgment delivers UCB its core commercial objective: blocking Prinston’s ANDA product from the US market for the life of the licensed patent. UCB retains the ability to selectively authorise Prinston under the Settlement Agreement — a mechanism sometimes used to launch authorised generics on terms favourable to the originator. Without disclosure of the Settlement Agreement’s full terms, it is unclear whether any launch date, royalty, or other commercial concession was granted to Prinston in exchange for the consent to injunction.
Market exclusivity protectedPrinston’s US generic launch blocked pending any authorised-entry clause
Prinston and Zhejiang Huahai are enjoined from commercialising their ANDA 218573 product in the United States unless UCB grants specific authorisation under the Settlement Agreement. The without-prejudice dismissal of affirmative defenses — which would typically include patent invalidity and non-infringement — means Prinston did not win a ruling that would benefit other generic filers. Zhejiang Huahai’s inclusion as an enjoined affiliate is notable, extending the injunction’s reach to the Chinese manufacturing parent and limiting any attempt to re-enter through a related entity.
Generic launch blockedHatch-Waxman settlement precedent strengthens UCB’s Briviact® IP perimeter
A settled ANDA case with a consent injunction — rather than a litigated invalidity finding — leaves US6911461 legally intact and unchallenged on the merits. Subsequent ANDA filers for brivaracetam cannot rely on this case as persuasive authority for invalidity. The settlement also signals that UCB is prepared to enforce the patent aggressively, which typically deters or delays further generic entry. Companies in the CNS/anti-epileptic space monitoring Briviact® exclusivity should note the patent’s remaining term when modelling generic entry risk.
Patent legally unchallengedFull party and counsel information
| Role | Name | Type | Detail |
|---|---|---|---|
| Plaintiff | UCB Pharma, Gmbh | Company | EU-headquartered CNS pharma group — holder of US6911461 covering Briviact® brivaracetamSearch in Eureka ↗ |
| Co-Plaintiff | UCB Biopharma, SRL | Individual | Search in Eureka ↗ |
| Defendant | Prinston Pharmaceutical, Inc. | Company | US generic drug subsidiary of Zhejiang Huahai Pharmaceutical; ANDA filer for brivaracetam tabletsSearch in Eureka ↗ |
| Co-Defendant | Zhejiang Huahai Pharmaceutical Co., Ltd. | Company | Search in Eureka ↗ |
| Plaintiff counsel | Jack B. Blumenfeld | Attorney | Counsel for UCB Pharma, GmbhSearch in Eureka ↗ |
| Plaintiff counsel | Karen Jacobs | Attorney | Counsel for UCB Pharma, GmbhSearch in Eureka ↗ |
| Plaintiff counsel | Megan Elizabeth Dellinger | Attorney | Counsel for UCB Pharma, GmbhSearch in Eureka ↗ |
| Plaintiff law firm | Morris, Nichols, Arsht & Tunnell LLP | Law Firm | Representing UCB Pharma, GmbhSearch in Eureka ↗ |
| Defendant counsel | Richard C. Weinblatt | Attorney | Counsel for Prinston Pharmaceutical, Inc.Search in Eureka ↗ |
| Defendant law firm | Stamoulis & Weinblatt LLC | Law Firm | Representing Prinston Pharmaceutical, Inc.Search in Eureka ↗ |
| Presiding judge | Judge Colm F. Connolly | Judge | Delaware District CourtSearch in Eureka ↗ |
Official order — verbatim text
The consent judgment’s operative language — enjoining Prinston, its affiliates, successors, and assigns from any US commercialisation of the ANDA 218573 product — is drafted broadly to prevent structural workarounds. Crucially, the injunction is keyed to the ‘Licensed Patent’ (US6911461) rather than to specific claims, meaning Prinston cannot argue that a reformulated product falls outside scope without returning to court. The without-prejudice dismissal of all affirmative defenses means no invalidity or non-infringement ruling was entered, leaving US6911461’s legal validity untested and intact for enforcement against other future ANDA filers.
US6911461 — brivaracetam composition patent covering Briviact® tablets
US Patent No. 6,911,461 (application no. 10/693,917) is the composition patent UCB asserts covers Briviact® (brivaracetam) tablets — a second-generation synaptic vesicle protein 2A (SV2A) ligand approved for the adjunctive treatment of partial-onset seizures. The patent protects the active compound and/or its formulation across the full commercial dosage range (10 mg to 100 mg). As a composition patent rather than a method-of-use patent, its claim scope typically extends to the molecule itself, providing broad protection against generic formulations regardless of the indication for which the ANDA is filed.
In the CNS pharmaceutical space, composition patents on approved small-molecule anti-epileptics are among the most commercially valuable IP assets because they gate generic entry for the entire approved product line. Brivaracetam competes in the crowded levetiracetam successor market, and US6911461’s enforcement against Prinston’s ANDA 218573 demonstrates UCB’s willingness to defend its exclusivity position aggressively. Any company formulating or licensing brivaracetam-based products for the US market must treat this patent as a primary FTO obstacle until its expiry or until UCB grants authorisation under the Settlement Agreement.
Should you run an FTO analysis against US6911461 for brivaracetam products?
Any pharmaceutical company, contract manufacturer, or licensing partner working with brivaracetam — or evaluating ANDA filings for anti-epileptic SV2A ligands in the US — should treat US6911461 as a live FTO risk. The consent judgment confirms UCB’s active enforcement posture, and the broad affiliate scope of the injunction signals that structural re-routing through related entities will not avoid liability. R&D teams developing follow-on or next-generation SV2A ligands should also assess claim scope to determine whether novel compounds fall within the patent’s protection.
PatSnap Eureka’s FTO Search Agent can map the full claim landscape of US6911461, identify related continuations, divisionals, and family members that may extend protection beyond this single patent, and flag prosecution history estoppel that could narrow or widen claim scope. Eureka’s litigation overlay also surfaces other ANDA cases in which UCB has asserted this or related patents, giving your IP team a complete picture of enforcement risk before filing an ANDA or committing R&D resources to a brivaracetam-adjacent programme.
Run a freedom-to-operate analysis on US6911461B2 to assess your product’s exposure
Run FTO in Eureka →Similar Hatch-Waxman ANDA cases involving CNS anti-epileptic patents in Delaware
Explore comparable ANDA infringement actions filed in Delaware District Court involving CNS anti-epileptic composition patents and consent judgment outcomes.
What this case signals for the Hatch-Waxman CNS pharma IP landscape
UCB’s swift resolution of the Prinston ANDA challenge offers a playbook for originator companies defending branded epilepsy treatments.
Speed of resolution suggests UCB leveraged the 30-month Hatch-Waxman stay effectively
Filing suit within the 45-day window triggered an automatic stay of ANDA approval, giving UCB negotiating leverage without needing a preliminary injunction. Settling in under 13 months — before the stay expired — is consistent with a strategy of locking in injunctive protection early rather than risking an adverse validity ruling at trial. Originators in similar positions should map stay expiry against settlement timelines.
Without-prejudice dismissal preserves UCB’s legal options if the Settlement Agreement is breached
Because all claims, including Prinston’s invalidity and non-infringement defenses, were dismissed without prejudice, neither side obtained a preclusive merits ruling. This is a double-edged outcome: UCB can re-file if Prinston violates the agreement, but Prinston retains theoretical ability to re-assert invalidity in any future dispute. IP teams monitoring this patent should track whether any breach or re-litigation occurs during the settlement’s term.
UCB v Prinston — key questions answered
The case closed on 13 February 2025 via a consent judgment and permanent injunction entered by Judge Colm F. Connolly in the Delaware District Court. Prinston Pharmaceutical and Zhejiang Huahai Pharmaceutical are enjoined from making, selling, or importing their ANDA 218573 brivaracetam product in the United States unless specifically authorised by UCB under the accompanying Settlement Agreement. All claims were dismissed without prejudice and without costs.
US6911461 is the composition patent UCB asserts covers Briviact® (brivaracetam) tablets — an SV2A ligand anti-epileptic approved for partial-onset seizures — across the 10 mg, 25 mg, 50 mg, 75 mg, and 100 mg dosage strengths. As a composition patent, it protects the underlying active compound and/or formulation, giving UCB broad rights to block generic versions regardless of the specific indication claimed in the ANDA.
A consent judgment is a court-entered order reflecting terms negotiated by the parties. Unlike a pure settlement agreement, it carries the force of a judicial decree, allowing the patent holder to seek contempt sanctions if the injunction is violated. In Hatch-Waxman ANDA cases, consent judgments typically include a permanent injunction barring the generic filer from commercialising its ANDA product, with a carve-out for any authorised launch date agreed in the confidential settlement agreement.
No. Because all claims and affirmative defenses — including invalidity and non-infringement — were dismissed without prejudice, no merits ruling was entered. The consent judgment does not constitute a judicial finding that US6911461 is valid or infringed. The patent’s legal validity therefore remains untested by this proceeding, and subsequent ANDA filers cannot rely on it as binding or persuasive authority on patentability.
Zhejiang Huahai Pharmaceutical Co., Ltd. is Prinston Pharmaceutical’s Chinese parent company and the entity that manufactures the active pharmaceutical ingredient and finished dosage forms underlying the ANDA. UCB named it as a co-defendant to ensure the injunction’s reach extended to the manufacturing parent, preventing any attempt to circumvent the order by having Zhejiang Huahai supply or distribute the product through a non-Prinston affiliate. The consent judgment explicitly binds Prinston’s affiliates, successors, and assigns.
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