Litigation Details for Abraxis Bioscience, LLC v. Mylan Pharmaceuticals, Inc. (N.D.W. Va. 2023)

Abraxis Bioscience, LLC v. Mylan Pharmaceuticals, Inc. (N.D.W. Va. 2023)

Docket		Date Filed	2023-04-06
Court	District Court, N.D. West Virginia	Date Terminated	2023-07-25
Cause	35:271 Patent Infringement	Assigned To	Thomas Shawn Kleeh
Jury Demand	None	Referred To
Patents	7,820,788
Link to Docket	External link to docket

Details for Abraxis Bioscience, LLC v. Mylan Pharmaceuticals, Inc. (N.D.W. Va. 2023)

Date Filed	Document No.	Description	Snippet	Link To Document
2023-04-06				External link to document

Abraxis Bioscience v. Mylan Pharmaceuticals, 1:23-cv-00033: Litigation Summary and Patent Analysis

Last updated: August 15, 2026

Abraxis Bioscience, LLC filed a Hatch-Waxman patent-infringement action against Mylan Pharmaceuticals, Inc. in the U.S. District Court for the District of Delaware on January 11, 2023. The dispute concerns Mylan’s proposed generic version of Abraxane, an albumin-bound paclitaxel product marketed by Bristol Myers Squibb. The case was triggered by Mylan’s abbreviated new drug application, or ANDA, and a Paragraph IV certification challenging patents listed for Abraxane.

The docket identifies the matter as a pharmaceutical patent case under 35 U.S.C. § 271(e)(2). The principal commercial issue is whether Mylan can launch generic paclitaxel protein-bound particles before the expiration of the asserted Abraxane patents. [1]

What drug and product are involved in Abraxis Bioscience v. Mylan?

The product is Abraxane, also known as paclitaxel protein-bound particles for injectable suspension.

Product	Active ingredient	Dosage form	NDA holder or sponsor	Therapeutic category
Abraxane	Paclitaxel bound to human albumin nanoparticles	Intravenous injectable suspension	Abraxis Bioscience, now associated with Bristol Myers Squibb	Oncology

Abraxane is approved for metastatic breast cancer, locally advanced or metastatic non-small cell lung cancer in combination with carboplatin, and metastatic adenocarcinoma of the pancreas in combination with gemcitabine. The product uses albumin-bound paclitaxel particles rather than the conventional solvent-based paclitaxel formulation.

Mylan’s ANDA product sought approval for a generic paclitaxel protein-bound particle formulation. The litigation therefore implicated product composition, manufacturing characteristics, labeling, and method-of-use patent rights rather than only the active pharmaceutical ingredient.

What patents protect Abraxane in the Mylan litigation?

The Abraxane patent estate has included formulation, composition, manufacturing, and treatment patents. Public FDA and patent records identify multiple patents associated with paclitaxel protein-bound particles, although the exact asserted patent set must be determined from the complaint, infringement contentions, and later docket filings. [2][3]

Relevant Abraxane-related patents have included the following categories:

Patent category	Protected subject matter	Generic-entry significance
Composition patents	Albumin-bound paclitaxel particles and particle characteristics	Can block approval or launch if the ANDA product falls within the claims
Formulation patents	Injectable suspensions, excipients, particle size, and concentration	May create technical design-around issues
Manufacturing patents	Processes for producing albumin-paclitaxel particles	Can create infringement exposure even where the finished product is similar
Method-of-use patents	Treatment of specified cancers with albumin-bound paclitaxel	Often tied to ANDA labeling and carve-out strategy
Dosage and administration patents	Dose schedules and administration methods	Can support partial or full label restrictions

Earlier Abraxane litigation involved patents including U.S. Patent Nos. 8,853,260, 9,011,885, 9,101,591, 9,370,164, and 9,572,822. Those patents covered aspects of albumin-bound paclitaxel compositions and methods. Their relevance to the Mylan case depends on the patents listed in the operative complaint and the patents identified in the ANDA notice. [4]

The most important legal distinction is between patents listed in the Orange Book and patents asserted in the complaint. A patent may be Orange Book-listed but not asserted against every ANDA applicant. Conversely, an infringement complaint may include only a subset of listed patents.

When was the Abraxis v. Mylan case filed?

Abraxis filed the complaint on January 11, 2023, in the District of Delaware under case number 1:23-cv-00033. The action followed Mylan’s ANDA Paragraph IV notice. Under the Hatch-Waxman framework, filing the suit within 45 days of receiving the notice triggered an automatic 30-month stay of FDA approval for the challenged ANDA, subject to statutory exceptions. [1][5]

Key procedural timeline

Date or period	Event
January 11, 2023	Abraxis filed the patent-infringement complaint
2023	Mylan responded through the pleadings and Hatch-Waxman litigation process
2023 onward	Discovery, claim-construction preparation, and validity and infringement analysis
Approximately 30 months after the Paragraph IV notice	Statutory FDA approval stay may expire unless modified by court action or another statutory event
Final judgment or settlement	Determines whether Mylan can launch before patent expiration

The filing date alone does not establish the end of the 30-month stay because the statutory clock begins with receipt of the ANDA notice, not necessarily the filing of the complaint.

What is the Orange Book status of Abraxane?

Abraxane has historically been protected by a combination of regulatory exclusivity and listed patents. The original five-year new chemical entity exclusivity associated with the product has expired. Commercial protection therefore depends primarily on patent rights, pediatric exclusivity where applicable, and the outcome of ANDA litigation. [2]

The Orange Book distinguishes between:

• patents claiming the drug substance;
• patents claiming the drug product or formulation;
• patents claiming approved methods of use; and
• patents that may support a Paragraph IV action.

For Abraxane, the principal risk to generic entry arises from formulation and method-of-use patents rather than a new active ingredient exclusivity period. FDA listing information must be reviewed by publication year because patent listings, delistings, expiration dates, and pediatric extensions can change over time. [2]

What Paragraph IV challenge did Mylan make?

Mylan’s Paragraph IV certification asserted that one or more patents listed for Abraxane were invalid, unenforceable, or would not be infringed by the proposed generic product. A Paragraph IV certification is an ANDA applicant’s legal position that FDA approval should not be blocked by the listed patent.

The certification does not itself invalidate a patent. It creates a litigation pathway under which the branded sponsor can sue under 35 U.S.C. § 271(e)(2). The court then evaluates infringement based on the ANDA, proposed labeling, and relevant manufacturing disclosures.

Mylan’s likely defenses fall into four groups:

1. Noninfringement. The proposed product does not satisfy one or more claim limitations.
2. Invalidity. The claims are anticipated, obvious, indefinite, or lack adequate written description or enablement.
3. Enforceability. The patents are unenforceable because of inequitable conduct or another litigation defense.
4. Regulatory limitation. The ANDA labeling or proposed use does not practice an asserted method-of-use claim.

The strongest defense depends on the asserted claims. Composition claims typically turn on particle structure, albumin association, and measurable product characteristics. Method claims turn on the proposed label and the treatment indication included in the ANDA.

What patent litigation affects generic Abraxane entry?

The Mylan action is part of a broader generic-entry dispute involving albumin-bound paclitaxel. Earlier Abraxane cases against generic applicants produced rulings concerning the scope and validity of formulation and treatment patents. Those decisions influence claim construction and obviousness arguments in later cases, but they do not automatically determine the outcome against Mylan.

Earlier Abraxane litigation

Abraxis previously litigated Abraxane patents against generic applicants, including Actavis and Teva-related entities. The Federal Circuit addressed issues involving albumin-bound paclitaxel patents, including obviousness, claim construction, and the evidentiary value of prior-art references. [4]

The earlier cases matter for three reasons:

• they narrow the range of claim constructions likely to be accepted;
• they provide arguments on whether albumin-bound paclitaxel was predictable from prior art; and
• they affect the value of remaining patents that share priority, specification, or inventorship history.

A prior validity decision does not necessarily eliminate later patents. Separate claims can protect different particle properties, process steps, dosing regimens, or cancer indications.

How strong is the Abraxane patent estate against Mylan?

The patent estate has moderate strategic strength because it combines several protection layers, but the core product is not protected by a single broad, unexpired active-ingredient patent.

Strengths

The estate has several potential advantages:

• Abraxane is a complex formulation rather than a simple small-molecule tablet.
• Product characteristics may be difficult for the ANDA applicant to avoid while maintaining pharmaceutical equivalence.
• Manufacturing disclosures can reveal infringement even when the final product appears commercially similar.
• Method-of-use claims can support a partial-label dispute where the ANDA seeks approval for multiple indications.
• Prior litigation has generated a substantial record concerning the technology and prior art.

Weaknesses

The estate also faces limitations:

• older Abraxane patents have expired or approach expiration;
• many claims are vulnerable to obviousness challenges based on known paclitaxel, albumin, nanoparticle, and injectable-formulation technologies;
• method-of-use claims may be avoidable through a skinny-label strategy;
• generic applicants can challenge claim scope using ANDA-specific product data;
• a 30-month stay delays approval but does not guarantee a launch prohibition.

The commercial value of the case depends less on the number of listed patents than on whether at least one unexpired patent has claims that read on Mylan’s product and survive validity challenges.

What formulations are protected by Abraxane patents?

Abraxane patents generally target the combination of paclitaxel with albumin in a particulate injectable formulation. Relevant claim concepts have included:

• paclitaxel associated with albumin;
• nanoparticle or particulate structures;
• particle-size distributions;
• formulations without conventional solvent systems;
• injectable suspensions;
• concentration and dosing parameters; and
• preparation methods that produce the claimed particles.

Formulation patents can be commercially important because a generic applicant may need to reproduce the branded product’s physical characteristics to satisfy FDA requirements for pharmaceutical equivalence. The applicant may still avoid infringement if its formulation or process falls outside a claim limitation.

The principal technical dispute is likely to concern whether the claims define the product by structure, function, process, or a combination of those elements. Structural claims are generally more useful against an ANDA product because infringement can be established from the product’s characteristics. Process claims require evidence concerning how Mylan manufactures the product.

What method-of-use patents affect Abraxane generic approval?

Abraxane’s approved uses include breast cancer, non-small cell lung cancer, and pancreatic cancer. Method-of-use patents can cover treatment of one or more of these indications, dosage schedules, combinations, or patient populations.

An ANDA applicant may attempt to omit a patented indication from its label through a section viii statement or a proposed labeling carve-out. That strategy is effective only if the remaining label does not encourage or require the patented use. Courts examine the complete proposed label, promotional implications, and whether the unpatented uses are substantial.

For Abraxane, a skinny-label strategy could reduce exposure for one indication while leaving disputes over the remaining indications. The commercial impact depends on the revenue contribution of the carved-out use and whether physicians prescribe the generic across indications despite the labeling restriction.

Which companies are challenging Abraxane exclusivity?

Mylan is the defendant in the identified case. Other generic companies have challenged or litigated Abraxane-related patents in earlier proceedings, including Actavis and Teva-associated entities. The competitive field includes manufacturers capable of producing sterile injectable oncology products and complex protein-associated formulations.

Generic competition is likely to develop in stages:

1. a first approved ANDA may receive a period of commercial advantage depending on the certification and litigation outcome;
2. subsequent applicants may rely on the first litigation result or pursue separate defenses;
3. multiple launches can produce rapid price erosion if the product is substitutable at major oncology centers.

Abraxane is more difficult to copy than a conventional immediate-release tablet, which can slow the number of qualified generic entrants. That manufacturing barrier can preserve price and market share after patent expiry, although it does not replace patent protection.

What generic launch scenarios exist for Mylan?

Scenario	Legal result	Commercial effect
Abraxis wins on infringement and validity	Mylan is blocked until the relevant patent barrier ends	Brand retains greater share during the exclusion period
Mylan wins on all asserted claims	FDA approval can proceed after regulatory requirements are satisfied	Early generic price competition is possible
Mylan wins on some claims	Remaining patents or indications may limit launch	Partial or delayed entry
Settlement with an agreed launch date	Entry occurs on a negotiated date	The parties avoid trial risk but may preserve a later launch
Patent expiry before final judgment	Litigation may become commercially moot	FDA approval and launch timing depend on regulatory status
Skinny-label approval	Mylan launches for nonpatented uses	Revenue loss depends on prescribing substitution

A settlement is particularly likely to focus on a licensed or agreed launch date, manufacturing restrictions, supply terms, or a no-challenge provision. No settlement terms should be treated as established without a filed agreement or court order.

What is the litigation status and likely next issue?

The central issues are claim scope, infringement based on Mylan’s ANDA, patent validity, and the timing of any FDA approval. The case does not involve biosimilar risk. Abraxane is a small-molecule drug product with a complex formulation, so the relevant pathway is an ANDA, not a biologics license application or biosimilar application.

The most important case documents for investment and launch analysis are:

• the complaint and any amended complaint;
• Mylan’s answer and counterclaims;
• the Paragraph IV notice;
• infringement and invalidity contentions;
• claim-construction briefing;
• expert reports;
• dispositive-motion rulings;
• trial judgment; and
• any settlement or consent order.

The docket should be read together with the FDA Orange Book and the relevant patent files. A docket entry showing that a case remains pending does not establish that every listed patent remains enforceable or commercially blocking.

How does Abraxane compare with conventional paclitaxel protection?

Abraxane has a different patent-risk profile from conventional paclitaxel products.

Issue	Abraxane	Conventional paclitaxel
Active ingredient	Paclitaxel	Paclitaxel
Primary differentiation	Albumin-bound particulate delivery system	Solvent-based formulation
Main patent risk	Formulation, composition, process, and use claims	Historically formulation and administration claims
Regulatory pathway	ANDA for generic equivalent	ANDA for generic equivalent
Biosimilar risk	None	None
Manufacturing complexity	Relatively high	Generally lower
Design-around potential	Constrained by equivalence and particle requirements	More established generic pathways

The formulation complexity may give the branded product more practical protection than the remaining patent term alone suggests. It also increases the risk that a generic entrant will face manufacturing, analytical, and regulatory delays even after prevailing in patent litigation.

Key Takeaways

• Abraxis filed the Delaware Hatch-Waxman case against Mylan on January 11, 2023.
• The dispute concerns Mylan’s proposed generic paclitaxel protein-bound particle product.
• The case involves Abraxane formulation and use protection, not biosimilar substitution.
• Mylan’s Paragraph IV certification triggered patent litigation and potentially a 30-month FDA approval stay.
• The commercial blocking strength depends on the specific asserted patents, claim limitations, and Mylan’s ANDA disclosures.
• Older Abraxane patents have expired or approach expiration, increasing the importance of later formulation and method-of-use patents.
• A victory on one patent does not necessarily block Mylan if other patents are invalid, expired, or not infringed.
• Generic entry could occur through an early launch, a negotiated settlement date, a partial label, or approval after patent expiry.
• The case docket, Orange Book listings, and patent prosecution histories must be evaluated together.

FAQs

Does Abraxis v. Mylan involve a biologic or biosimilar application?

No. The case involves an ANDA for a generic drug product. Abraxane is a complex formulation, but it is not being challenged through the biosimilar pathway.

What does a Paragraph IV certification mean for Abraxane?

It means Mylan asserted that one or more listed Abraxane patents are invalid, unenforceable, or not infringed. The certification permits the branded sponsor to file a Hatch-Waxman infringement action.

Can Mylan launch Abraxane before all patents expire?

Mylan can potentially launch before patent expiry if it obtains a favorable judgment, reaches a settlement with an agreed launch date, or proceeds after the applicable FDA approval stay ends without an effective injunction.

Are Abraxane formulation patents more important than method-of-use patents?

Formulation patents are generally more difficult to avoid when the generic must reproduce the branded product’s key characteristics. Method-of-use patents may be more susceptible to label carve-outs, depending on the approved indications and claim language.

Does a prior Abraxane patent decision automatically resolve the Mylan case?

No. Earlier decisions may influence claim construction, obviousness, and infringement arguments, but the court must analyze the specific claims and ANDA disclosures at issue in the Mylan case.

References

1. U.S. District Court for the District of Delaware. (2023). Abraxis Bioscience, LLC v. Mylan Pharmaceuticals, Inc., No. 1:23-cv-00033. PACER/CourtListener docket record.
2. U.S. Food and Drug Administration. (2024). Approved drug products with therapeutic equivalence evaluations: Orange Book.
3. U.S. Patent and Trademark Office. (2024). Patent Center: U.S. patent and application records for paclitaxel protein-bound particle products.
4. U.S. Court of Appeals for the Federal Circuit. (2019). Decisions concerning Abraxane-related patent litigation and albumin-bound paclitaxel patents.
5. Hatch-Waxman Act, 21 U.S.C. § 355(j); 35 U.S.C. § 271(e)(2).