Pacira EXPAREL Patent Settlement: Terms, Exclusions, and Fallout

The Pacira EXPAREL patent settlement, announced April 7, 2025, resolves years of litigation with Fresenius Kabi and its partners by keeping EXPAREL free of generic competition until early 2030, then allowing a volume-limited generic that expands in stages until all caps come off on January 1, 2039. Pacira retains full market exclusivity for roughly five more years, and Fresenius gains a defined, gradual path into the market well before Pacira’s last Orange Book patent expires in July 2044.

Why the Patents Matter

EXPAREL is an injectable suspension of bupivacaine encapsulated in multivesicular liposomes, used for extended post-surgical pain relief without opioids. It is Pacira’s dominant product and the anchor of its revenue.¹

Pacira lists 21 patents covering EXPAREL in the FDA’s Orange Book, split across two families. The older family includes U.S. Patent No. 11,033,495 (the ‘495 patent), which covers manufacturing aspects of the liposome product. The newer family is anchored by U.S. Patent No. 12,156,940 (the ‘940 patent), which covers the composition made through Pacira’s enhanced large-scale San Diego process, approved by the FDA in February 2024. Pacira describes the newer family as stronger than the first, with protection extending through July 2044.²³

How the Case Ended in a Settlement

Pacira sued eVenus Pharmaceutical Laboratories in the U.S. District Court for the District of New Jersey in November 2021, alleging that eVenus’s generic EXPAREL infringed the ‘495 patent. A second suit followed in February 2022, adding dosage strengths and further patents. Fresenius Kabi USA and Jiangsu Hengrui Pharmaceuticals, affiliated with eVenus, were also parties to the broader litigation.⁴

After a bench trial, the New Jersey court ruled on August 9, 2024, that Claim 7 of the ‘495 patent was invalid on both obviousness and anticipation grounds, and that eVenus did not infringe it.⁵ The FDA had already approved eVenus’s ANDA for two single-dose vial strengths on July 1, 2024, finding the product bioequivalent and therapeutically equivalent to EXPAREL.⁶ Pacira appealed to the Federal Circuit in September 2024.⁷

The appeal never produced a merits decision. Three days after the April 7, 2025, settlement announcement, Pacira voluntarily dismissed the appeal.⁸ The ‘495 patent later underwent USPTO reexamination and was reissued with amended claims.³

What the Settlement Says

The agreement grants Fresenius a non-exclusive, royalty-free license to sell generic bupivacaine liposome injectable suspension in the United States, subject to volume caps that ramp up over roughly a decade.⁹¹⁰

Starting in early 2030, Fresenius may sell a generic capped at a high-single-digit percentage of total U.S. market volume.
The permitted volume increases every 12 months, reaching the low thirties percentage by 2033 and continuing to grow modestly for two more years.
In the final three capped years, volume tops out in the high thirties percentage of the market.
On January 1, 2039, all volume restrictions come off and Fresenius may sell the generic without limit.

Unusually for a Hatch-Waxman resolution, Pacira paid Fresenius Kabi $7 million as part of the deal.⁹ The parties agreed to file consent judgments in the Federal Circuit, the District of New Jersey, and the Northern District of Illinois that bar Fresenius from marketing generic EXPAREL outside the settlement’s terms.¹⁰

Fresenius also agreed not to challenge the validity of six Pacira patents (U.S. Patent Nos. 11,179,336; 11,278,494; 11,304,904; 11,311,486; 11,357,727; and 11,452,691) unless Pacira first asserts them against Fresenius. Pacira, for its part, waived any regulatory exclusivities that might have blocked the FDA from approving Fresenius’s generic in time for the license start date.⁹

What the Settlement Does Not Cover

The deal binds Fresenius Kabi, Jiangsu Hengrui, and eVenus. It does not bind other generic makers, and Pacira is already fighting the next wave.

In October 2025, Pacira disclosed that The WhiteOak Group, a subsidiary of the Chinese company Zhejiang Haichang Biotechnology, had filed its own ANDA for a generic EXPAREL. WhiteOak’s Paragraph IV certification letter alleged that 19 of Pacira’s Orange Book patents are invalid, unenforceable, or would not be infringed. Pacira noted that neither WhiteOak nor its parent had any commercialized products at the time of the filing.¹¹

On November 26, 2025, Pacira sued WhiteOak and Qilu Pharmaceutical (Hainan) Co., Ltd. in the U.S. District Court for the District of Delaware, asserting nine patents drawn from both families. Under the Hatch-Waxman Act, that filing triggered an automatic 30-month stay on final FDA approval of the defendants’ ANDAs. A separate case Pacira had filed against Qilu in the Eastern District of Pennsylvania was voluntarily dismissed without prejudice in February 2026, before Qilu was served.¹²¹³ The Delaware case is in active discovery before Judge Jennifer L. Hall, with a bench trial scheduled to begin October 4, 2027.¹⁴

Whether a WhiteOak or Qilu generic reaches the market before 2030 depends on how those cases resolve. The Fresenius settlement does not stop them.

Fallout for Investors

The August 2024 invalidity ruling also produced a securities class action, Alvarez v. Pacira Biosciences, Inc. et al (Case No. 2:25-cv-00322), filed in the District of New Jersey. The complaint alleged that between August 2, 2023, and August 8, 2024, Pacira misled investors about the strength of its EXPAREL patent protections, particularly the ‘495 patent.¹⁵ The Western Pennsylvania Teamsters and Employers Pension Fund was appointed lead plaintiff in May 2025. On February 6, 2026, the court granted Pacira’s motion to dismiss with prejudice. The lead plaintiff has appealed to the Third Circuit, where the case remains pending as of mid-2026.¹⁶

The settlement’s structure has also drawn activist attention. DOMA Perpetual Capital Management launched a proxy contest ahead of Pacira’s June 9, 2026, annual meeting, accusing the board of gross negligence in managing patent risks and urging the company to explore strategic alternatives, including a possible sale. DOMA cited a 46% decline in the stock price over the preceding decade.¹⁷ Pacira called DOMA’s claims inaccurate and pointed to the Fresenius settlement’s exclusivity window, the newer patent family, and its 21 Orange Book patents as evidence that EXPAREL remains protected.³

1
GlobeNewsWire. Pacira BioSciences Reports Second Quarter 2025 Financial Results
2
BioSpace. Pacira Awarded New U.S. Patent Covering EXPAREL Composition
3
Pacira BioSciences Investor Relations. Pacira BioSciences Sets the Record Straight Regarding DOMA’s
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Kehoe Law Firm. Pacira BioSciences Complaint
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Pacira BioSciences Investor Relations. Pacira BioSciences Comments on Ruling in EXPAREL Patent Litigation
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U.S. Food and Drug Administration. ANDA 214348 Approval Letter
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U.S. Securities and Exchange Commission. Pacira BioSciences SEC Filing
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PatSnap. Pacira v. eVenus Fresenius Kabi Bupivacaine Liposome Patent Appeal
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Justia Contracts. Pacira Pharmaceuticals Settlement Agreement
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Pacira BioSciences Investor Relations. Pacira BioSciences Announces Settlement of U.S. Patent Litigation
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Pacira BioSciences Investor Relations. Pacira BioSciences Notified of Abbreviated New Drug Application Filing From the WhiteOak Group for EXPAREL
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Pacira BioSciences Investor Relations. Pacira BioSciences Files EXPAREL Patent Infringement Lawsuits
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PatSnap. Pacira Pharmaceuticals vs. Qilu EXPAREL Patent Dismissal
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CourtListener. Pacira Pharmaceuticals, Inc. v. The WhiteOak Group, Inc.
15
BusinessWire. Rosen Law Firm Urges Pacira BioSciences Stockholders to Contact the Firm
16
PACER Monitor. Alvarez v. Pacira Biosciences, Inc. et al
17
PR Newswire. A Letter to Pacira BioSciences Shareholders From DOMA Perpetual Capital Management