Azurity & Takeda v. Zydus: EDARBI® Patent Dispute Dismissed Without Prejudice
Azurity Pharmaceuticals, Takeda Pharmaceutical, and Arbor Pharmaceuticals brought a patent infringement action against Zydus entities in the Delaware District Court over three patents covering azilsartan medoxomil formulations — including the branded antihypertensive products EDARBI® and EDARBYCLOR®. After 516 days of litigation, all claims were dismissed without prejudice with each side bearing its own costs.
Three-Patent ANDA Battle Over Azilsartan Antihypertensives Ends in Stipulated Exit
Filed on 2 August 2023 before Judge Maryellen Noreika in the Delaware District Court, this Hatch-Waxman infringement action pitted Azurity Pharmaceuticals, Takeda Pharmaceutical Company Limited, and Arbor Pharmaceuticals against Cadila Healthcare and its Zydus affiliates. At stake were three US patents — US9169238B2, US9066936B2, and US9387249B2 — covering azilsartan medoxomil formulations and azilsartan medoxomil/chlorthalidone combination products marketed as EDARBI® and EDARBYCLOR®.
On 30 December 2024, the parties filed a joint stipulation under Federal Rule of Civil Procedure 41(a)(1)(A)(ii) dismissing all claims, counterclaims, and defenses without prejudice. Crucially, the stipulation specifies that each side bears its own attorney fees and costs, with no admission of liability or validity determination on the merits. The without-prejudice designation preserves the plaintiffs’ right to refile should Zydus’s ANDA application progress toward market entry.
The 516-day duration — ending just before the close of the calendar year — suggests the parties may have reached a commercial accommodation, potentially including a confidential settlement or agreed licensing terms, though the public record is silent on any such arrangement. The absence of a consent judgment or royalty stipulation leaves the strategic rationale opaque. For Zydus, dismissal without prejudice removes an immediate injunction risk while the without-prejudice designation signals no clear victory on patent validity.
Filing to Dismissed without Prejudice in 516 days
516 days in litigation — roughly 17 months, typical for a Hatch-Waxman ANDA case before trial
Dismissed without prejudice: what the stipulation means for each party
Rule 41(a)(1)(A)(ii) dismissal — no merits ruling issued
A stipulated dismissal under Rule 41(a)(1)(A)(ii) requires agreement of all parties and takes effect immediately upon filing — no court order is needed. Critically, ‘without prejudice’ means the dismissal carries no res judicata effect: plaintiffs retain the right to refile the same infringement claims if Zydus’s ANDA advances toward market launch. No validity or infringement finding was made.
No merits adjudicationWithout prejudice: the door remains open for plaintiffs
A dismissal without prejudice contrasts sharply with one ‘with prejudice,’ which would permanently bar re-litigation of the same claims. Here, Azurity, Takeda, and Arbor preserve full enforcement rights. Should Zydus receive FDA approval and move toward commercialising its generic azilsartan product, plaintiffs could recommence infringement proceedings on the same three patents without the case being time-barred by this dismissal.
Claims preservedZydus avoids an adverse ruling — but patents remain live
For Zydus, the dismissal removes the immediate litigation overhang and the risk of a preliminary injunction blocking FDA approval. However, none of the three asserted patents has been declared invalid or not infringed. Zydus’s ANDA pathway remains subject to potential re-litigation if it seeks market entry, meaning this outcome is a procedural reprieve rather than a cleared path to commercialisation.
No validity clearanceGeneric azilsartan launch timeline remains uncertain
The without-prejudice dismissal is consistent with a confidential settlement or negotiated market entry date, though the public record does not confirm this. Competing generic filers targeting EDARBI® and EDARBYCLOR® should monitor Zydus’s ANDA status closely. The three patents — with application dates suggesting protection through the mid-2020s — continue to present enforcement risk for any party seeking early generic entry into the azilsartan medoxomil market.
Generic entry risk persistsFull party and counsel information
| Role | Name | Type | Detail |
|---|---|---|---|
| Plaintiff | Azurity Pharmaceuticals, Inc. | Company | Pharmaceutical patent holders — branded EDARBI® and EDARBYCLOR® antihypertensive productsSearch in Eureka ↗ |
| Co-Plaintiff | Takeda Pharmaceutical Company Limited | Company | Search in Eureka ↗ |
| Co-Plaintiff | Arbor Pharmaceuticals, LLC | Company | Search in Eureka ↗ |
| Defendant | Cadila Healthcare, Ltd. | Company | Zydus generic pharmaceutical group seeking ANDA approval for azilsartan medoxomil productsSearch in Eureka ↗ |
| Co-Defendant | Zydus Lifesciences Limited | Individual | Search in Eureka ↗ |
| Co-Defendant | Zydus Pharmaceuticals (USA), Inc. | Company | Search in Eureka ↗ |
| Plaintiff counsel | Alexandra M. Joyce | Attorney | Counsel for Azurity Pharmaceuticals, Inc.Search in Eureka ↗ |
| Plaintiff counsel | Daniel M. Silver | Attorney | Counsel for Azurity Pharmaceuticals, Inc.Search in Eureka ↗ |
| Plaintiff counsel | Maliheh Zare | Attorney | Counsel for Azurity Pharmaceuticals, Inc.Search in Eureka ↗ |
| Plaintiff counsel | Sarah E. Spencer | Attorney | Counsel for Azurity Pharmaceuticals, Inc.Search in Eureka ↗ |
| Plaintiff law firm | McCarter & English LLP | Law Firm | Representing Azurity Pharmaceuticals, Inc.Search in Eureka ↗ |
| Defendant counsel | Emily L. Savas | Attorney | Counsel for Cadila Healthcare, Ltd.Search in Eureka ↗ |
| Defendant counsel | Hannah J. Thomas | Attorney | Counsel for Cadila Healthcare, Ltd.Search in Eureka ↗ |
| Defendant counsel | Jonathan B. Turpin | Attorney | Counsel for Cadila Healthcare, Ltd.Search in Eureka ↗ |
| Defendant counsel | Michael J. Gaertner | Attorney | Counsel for Cadila Healthcare, Ltd.Search in Eureka ↗ |
| Defendant counsel | Pilar Gabrielle Kraman | Attorney | Counsel for Cadila Healthcare, Ltd.Search in Eureka ↗ |
| Defendant law firm | Young Conaway Stargatt & Taylor, LLP | Law Firm | Representing Cadila Healthcare, Ltd.Search in Eureka ↗ |
| Presiding judge | Judge Maryellen Noreika | Judge | Delaware District CourtSearch in Eureka ↗ |
Official order — verbatim text
The stipulation’s explicit invocation of Rule 41(a)(1)(A)(ii) and the ‘without prejudice’ designation are legally significant: no court adjudication occurred, meaning neither validity nor infringement was determined. The phrase ‘dismissed in their entirety’ — covering all claims, counterclaims, and defences — ensures a clean procedural record. The mutual cost-bearing provision removes any fee-shifting asymmetry, suggesting a negotiated exit rather than a concession by either side. The patents remain fully enforceable against Zydus and any other generic entrant.
US9169238B2, US9066936B2 & US9387249B2 — Azilsartan Medoxomil Formulations
The three patents-in-suit cover the core chemistry and formulation science underlying EDARBI® (azilsartan medoxomil) and EDARBYCLOR® (azilsartan medoxomil with chlorthalidone diuretic). Azilsartan medoxomil is an angiotensin II receptor blocker (ARB) indicated for the treatment of hypertension. The patents — filed with application numbers in the US12/7xxxxx and US12/4xxxxx series — reflect a layered IP strategy covering both the active compound and its therapeutically relevant combination with a thiazide-type diuretic at clinically differentiated dosage strengths (12.5 mg and 25 mg chlorthalidone; 40 mg and 80 mg azilsartan medoxomil).
This patent portfolio represents the standard Hatch-Waxman Orange Book protection strategy for a branded ARB franchise with significant commercial value. The combination of three patents across single-agent and fixed-dose combination products creates overlapping protection that any generic ANDA filer must navigate. For competitors, invalidity challenges via IPR at the PTAB or full Paragraph IV litigation remain the primary mechanisms to clear these patents ahead of any authorised launch window.
Should you run an FTO analysis against US9169238B2, US9066936B2 & US9387249B2?
Any pharmaceutical company — generic, authorised generic, or biosimilar adjacent — developing azilsartan medoxomil tablets or azilsartan/chlorthalidone fixed-dose combinations at the commercially relevant dosage strengths (40 mg, 80 mg azilsartan; 12.5 mg, 25 mg chlorthalidone) should treat these three patents as live enforcement risk. The without-prejudice dismissal confirms no invalidity finding; all three patents remain Orange Book-listed and fully assertable.
PatSnap Eureka’s FTO Search Agent enables R&D and regulatory teams to map claim scope across US9169238B2, US9066936B2, and US9387249B2 against proposed ANDA formulations, identify potential design-arounds, and track any pending IPR or ex parte reexamination proceedings that could alter the risk landscape before committing to a Paragraph IV certification strategy.
Run a freedom-to-operate analysis on US9169238B2 to assess your product’s exposure
Run FTO in Eureka →Similar Hatch-Waxman Cases: Azilsartan & ARB Formulation Patent Disputes
Explore related ANDA patent infringement cases involving azilsartan medoxomil, ARB antihypertensives, and Hatch-Waxman dismissals filed in the Delaware District Court.
What this case signals for the branded antihypertensive IP landscape
This Hatch-Waxman stipulation carries implications beyond Zydus — any ANDA filer targeting azilsartan products faces live patent risk.
Without-prejudice exits are a strategic patent holder tool in ANDA disputes
Dismissing without prejudice allows branded pharmaceutical plaintiffs to manage litigation costs while retaining full enforcement optionality. If Zydus’s ANDA stalls at the FDA, the patents effectively remain unchallenged on the merits — a favourable holding position for Azurity, Takeda, and Arbor without the cost of a full trial.
Three live patents cover overlapping azilsartan formulations — creating layered risk
US9169238B2, US9066936B2, and US9387249B2 together cover both the single-agent azilsartan medoxomil product (EDARBI®) and the combination product with chlorthalidone (EDARBYCLOR®). Any generic entrant must clear all three patents, raising the bar for invalidity challenges and freedom-to-operate clearance across dosage strengths.
Azurity v Cadila — key questions answered
The case was dismissed without prejudice on 30 December 2024 via a joint stipulation under Federal Rule of Civil Procedure 41(a)(1)(A)(ii). All claims, counterclaims, and defences were dismissed in their entirety, with each side bearing its own attorney fees and costs. No merits ruling was issued on patent validity or infringement.
Three US patents were asserted: US9169238B2, US9066936B2, and US9387249B2. These patents cover azilsartan medoxomil formulations and the azilsartan medoxomil/chlorthalidone fixed-dose combination products marketed as EDARBI® and EDARBYCLOR® at various dosage strengths.
No. A dismissal without prejudice carries no res judicata effect and does not constitute a finding of invalidity or non-infringement. The three asserted patents remain enforceable. Plaintiffs retain the right to refile infringement claims against Zydus if it seeks commercial launch of its generic azilsartan product following FDA approval.
Requiring each party to bear its own attorney fees and costs — rather than fee-shifting to either side — is structurally consistent with a negotiated commercial resolution, potentially including a confidential settlement or agreed launch date. It avoids any implication of wrongful conduct by either party. The public record does not confirm or deny a separate commercial agreement.
No. The stipulated dismissal binds only the named Zydus entities. Any other ANDA applicant for azilsartan medoxomil or azilsartan/chlorthalidone products cannot rely on this dismissal as a validity or non-infringement precedent. All three patents — US9169238B2, US9066936B2, and US9387249B2 — remain assertable against other generic challengers.
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