Alkermes v. Apotex: LYBALVI® Patent Suit Dismissed in 67 Days
Alkermes filed a three-patent infringement action against Apotex in Delaware over its LYBALVI® (olanzapine/samidorphan) product, asserting US12390474, US11707466, and US11951111. Within 67 days — before Apotex filed any responsive pleading — Alkermes voluntarily dismissed all claims without prejudice under Rule 41(a)(1)(A)(i), with each side bearing its own costs.
Pre-answer dismissal in a high-stakes branded antipsychotic ANDA dispute
On August 28, 2025, Alkermes, Inc. and Alkermes Pharma Ireland Limited filed suit in the U.S. District Court for the District of Delaware against Apotex Corp. and Apotex Inc., asserting infringement of three patents — US12390474B2, US11707466B2, and US11951111B2 — all directed to LYBALVI®, the branded fixed-dose combination of olanzapine and samidorphan indicated for schizophrenia and bipolar disorder. The suit, assigned to Judge Colm F. Connolly, is consistent with standard Hatch-Waxman ANDA litigation triggered by Apotex’s generic filing.
On November 3, 2025 — just 67 days after filing — Alkermes filed a Notice of Voluntary Dismissal under Federal Rule of Civil Procedure 41(a)(1)(A)(i), dismissing all claims against both Apotex entities without prejudice. Because Apotex had not yet served an answer or motion for summary judgment at that point, Alkermes was entitled to dismiss as of right, requiring no court order. Each party was designated to bear its own attorneys’ fees and costs, meaning no adverse cost award was entered against either side.
A 67-day lifespan before any responsive pleading is notably brief for Hatch-Waxman litigation, which typically runs years. The without-prejudice dismissal preserves Alkermes’s right to refile the same claims, suggesting a possible negotiated arrangement, a strategic reset, or a shift in enforcement timing rather than a concession on the merits. The public record does not disclose whether a settlement, covenant not to sue, or licensing arrangement underlies the dismissal, leaving the commercial resolution between the parties undisclosed.
Filing to Voluntary dismissal in 67 days
67-day lifespan — resolved before defendant filed an answer or summary judgment motion
Voluntarily dismissed: what the Rule 41 exit means for both parties
Rule 41(a)(1)(A)(i): dismissal as of right, no court order needed
Federal Rule of Civil Procedure 41(a)(1)(A)(i) permits a plaintiff to dismiss an action without a court order at any time before the defendant serves an answer or motion for summary judgment. Because Apotex had filed neither, Alkermes held an unconditional right to exit. The dismissal takes effect upon filing the notice — no judicial approval required, and the court has no discretion to deny it.
Procedural exit — no merits rulingWithout prejudice: claims survive, but the public record is silent on why
A without-prejudice dismissal means the underlying patent claims are not extinguished — Alkermes retains the right to refile suit on the same three patents against Apotex in the future. This contrasts with a with-prejudice dismissal, which would bar re-litigation. The notice expressly states "without prejudice," but the public record does not disclose whether a licensing deal, covenant not to sue, or other commercial arrangement drove the decision to exit at this stage.
Re-filing right preservedAlkermes exits intact: no adverse ruling, patents unscathed
Alkermes bears no estoppel, no adverse merits finding, and no invalidity determination from this action. All three LYBALVI® patents — US12390474, US11707466, and US11951111 — remain in force and unchallenged by any court ruling in this case. The without-prejudice exit leaves Alkermes free to reassert these patents against Apotex or other ANDA filers at a later date, preserving the full defensive value of its LYBALVI® IP portfolio.
Patent enforceability intactApotex avoids litigation — for now — but faces lingering uncertainty
Apotex exits without an invalidity or non-infringement ruling in its favour. While no injunction or damages were awarded, the without-prejudice dismissal means Alkermes can reinitiate proceedings. Apotex’s generic LYBALVI® launch remains subject to any 30-month stay triggered by the original ANDA filing, and the commercial path to market depends on unresolved patent and regulatory timelines that the public record does not illuminate.
No clearance for generic launchFull party and counsel information
| Role | Name | Type | Detail |
|---|---|---|---|
| Plaintiff | Alkermes, Inc. | Company | Specialty pharmaceutical company — holder of US12390474, US11707466, and US11951111 covering LYBALVI®Search in Eureka ↗ |
| Defendant | Apotex, Inc. | Company | Canadian generic pharmaceutical manufacturer; filed ANDA for generic LYBALVI® (olanzapine/samidorphan)Search in Eureka ↗ |
| Plaintiff counsel | James Darlington Taylor , Jr. | Attorney | Counsel for Alkermes, Inc.Search in Eureka ↗ |
| Plaintiff counsel | Michelle Streifthau-Livizos | Attorney | Counsel for Alkermes, Inc.Search in Eureka ↗ |
| Plaintiff law firm | Saul Ewing Arnstein & Lehr LLP | Law Firm | Representing Alkermes, Inc.Search in Eureka ↗ |
| Presiding judge | Judge Colm F. Connolly | Judge | Delaware District CourtSearch in Eureka ↗ |
Official order — verbatim text
The notice of dismissal invokes Rule 41(a)(1)(A)(i) explicitly, confirming the procedural basis for the unilateral exit — no court order, no merits adjudication. The "without prejudice" designation is the operative phrase: it preserves Alkermes’s full right to refile identical claims. The fee-bearing provision — each party covering its own costs — is consistent with negotiated exits and does not indicate any finding of improper conduct by either side. No invalidity, non-infringement, or unenforceability determination was made against any of the three asserted patents.
US12390474, US11707466 & US11951111 — LYBALVI® (olanzapine/samidorphan) formulation patents
The three patents at issue — US12390474B2, US11707466B2, and US11951111B2 — all relate to LYBALVI®, Alkermes’s fixed-dose combination of olanzapine (an atypical antipsychotic) and samidorphan (an opioid antagonist designed to mitigate olanzapine-associated weight gain). Application numbers US18/510585, US17/855242, and US18/327229 reflect a continuation filing strategy, suggesting a deliberate effort to build layered claims around the same core product, potentially covering formulation, method of use, and manufacturing aspects across separate patents.
For the antipsychotic and CNS pharmaceutical sector, a multi-patent LYBALVI® portfolio represents a significant market exclusivity tool. LYBALVI® competes in a large market for schizophrenia and bipolar I disorder treatments, and generic olanzapine is well established — meaning Alkermes’s commercial differentiation depends substantially on samidorphan-related IP. Any generic filer must navigate all three patents, raising the complexity and cost of any successful ANDA challenge. Competitors and ANDA filers should assess the distinct claim scope of each patent individually.
Should your ANDA or generic program run an FTO against US12390474, US11707466, and US11951111?
Any pharmaceutical company developing a generic or biosimilar version of a fixed-dose olanzapine/samidorphan combination product — or any CNS formulation using opioid receptor modulation to manage atypical antipsychotic side effects — should conduct a rigorous freedom-to-operate analysis against all three Alkermes patents. The without-prejudice dismissal means these patents remain fully enforceable and Alkermes has explicitly preserved its right to refile. The 30-month stay mechanism under Hatch-Waxman makes timing of any FTO analysis critical.
PatSnap Eureka’s FTO Search Agent can map the claim scope of US12390474B2, US11707466B2, and US11951111B2 against your product formulation, identify prosecution history estoppel, surface related continuations or divisionals in the Alkermes portfolio, and benchmark against prior ANDA litigation outcomes. For R&D teams designing around these patents, Eureka can also identify prior art landscapes that may support future IPR petitions if Alkermes refiles.
Run a freedom-to-operate analysis on US12390474B2 to assess your product’s exposure
Run FTO in Eureka →Similar ANDA patent infringement cases in Delaware District Court
Explore comparable Hatch-Waxman ANDA infringement actions involving CNS and antipsychotic formulation patents litigated in the District of Delaware.
What this case signals for the branded antipsychotic IP landscape
A swift pre-answer withdrawal in a multi-patent ANDA case often signals more than a simple exit — the resolution terms matter.
Pre-answer ANDA dismissals frequently mask undisclosed commercial agreements
When a brand files a Hatch-Waxman suit and then withdraws without prejudice before the defendant even answers, it typically suggests behind-the-scenes negotiation — a licensing deal, authorised generic arrangement, or entry date agreement. The absence of any cost award here reinforces that interpretation. Competitors and investors tracking LYBALVI® market exclusivity should monitor for any subsequent 180-day exclusivity or authorised generic disclosures.
Three-patent portfolio signals Alkermes’s layered exclusivity strategy for LYBALVI®
Asserting US12390474, US11707466, and US11951111 simultaneously demonstrates a stacked patent portfolio approach — each patent likely covers distinct aspects of the olanzapine/samidorphan formulation, potentially extending exclusivity across multiple claim types. This is a recognised brand strategy in Hatch-Waxman litigation to maximise the 30-month stay period and deter generic entry.
Alkermes v Apotex — key questions answered
A without-prejudice dismissal under Rule 41(a)(1)(A)(i) means Alkermes ended the case without any merits ruling and retains the full right to refile identical patent claims against Apotex in the future. No invalidity or non-infringement finding was made. The three LYBALVI® patents — US12390474, US11707466, and US11951111 — remain enforceable.
Alkermes asserted three U.S. patents: US12390474B2 (App. No. US18/510585), US11707466B2 (App. No. US17/855242), and US11951111B2 (App. No. US18/327229). All three relate to LYBALVI®, a fixed-dose combination of olanzapine and samidorphan used to treat schizophrenia and bipolar I disorder.
The public record does not disclose the reason. A 67-day pre-answer withdrawal without prejudice is consistent with a negotiated commercial resolution — such as a licensing deal, authorised generic arrangement, or agreed entry date — but none of these has been publicly confirmed. The absence of any cost award is consistent with a negotiated rather than adversarial exit.
The dismissal of the civil action does not automatically terminate any 30-month stay that was triggered when Alkermes filed suit in response to Apotex’s Paragraph IV ANDA certification. The regulatory timeline at the FDA is governed separately. Apotex’s path to market depends on the stay expiry date, any subsequent refiling by Alkermes, and FDA approval — none of which are determined by this dismissal alone.
Alkermes is represented by James Darlington Taylor Jr. and Michelle Streifthau-Livizos of Saul Ewing Arnstein & Lehr LLP. No defense counsel of record has been listed in the available case data, consistent with the defendant not having filed an answer before dismissal.
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