United States Drug Patent 6,169,084: Scope, Claims, Expiration, and Olanzapine Pamoate Patent Landscape

U.S. Patent No. 6,169,084 covers olanzapine pamoate salts, defined solvates, and pharmaceutical treatment methods using those compounds. The patent was assigned to Eli Lilly and Company and issued January 2, 2001. Its principal commercial significance was the protection of long-acting or otherwise modified olanzapine salt forms rather than conventional olanzapine free base. The patent term has ended, with the 20-year term running from the relevant U.S. application filing date and expiring in 2019, subject to any applicable patent-term adjustment.

The patent does not protect all olanzapine products. Its composition claims are directed to olanzapine combined with pamoic acid, including specified dimethanol, water, acetone, and tetrahydrofuran solvates. Its method claim covers treatment of psychosis, acute mania, or mild anxiety states with the claimed compounds. The patent does not create current Orange Book protection for marketed Zyprexa products because olanzapine pamoate was not the active ingredient in the FDA-approved Zyprexa products.

What does U.S. Patent 6,169,084 cover?

U.S. Patent 6,169,084 covers olanzapine pamoate as a chemical composition and several characterized solid-state forms. The patent also claims administration of those compositions to treat specified psychiatric conditions.

Patent feature	Scope
Patent number	U.S. 6,169,084
Title	Olanzapine pamoate
Assignee	Eli Lilly and Company
Issue date	January 2, 2001
Principal subject matter	Olanzapine pamoate salts and solvates
Solid forms expressly claimed	Dimethanolate, monohydrate, acetone solvate, monohydrate solvate, THF solvate
Medical-use indications	Psychosis, acute mania, mild anxiety states
Patent status	Expired after the original patent term
FDA product relationship	Not the active ingredient in approved Zyprexa tablets or orally disintegrating tablets

The patent is a composition-of-matter patent for a salt and solvate family. It is not limited to a particular tablet, injection device, excipient system, manufacturing process, particle-size distribution, or release profile unless those limitations are imported through a separate claim or a claim-construction analysis.

What does claim 1 of U.S. 6,169,084 protect?

Claim 1 recites:

“A compound which is an olanzapine pamoate salt or a solvates thereof.”

Claim 1 is the broad composition claim. It covers the combination of olanzapine with pamoic acid in salt form and solvated versions of that salt.

The claim has several important scope characteristics:

It is directed to a compound, not merely a process for making the compound.
It is directed to the pamoate counterion, not olanzapine free base.
It expressly reaches solvates.
It does not require the specific X-ray powder diffraction pattern recited in claims 2 through 6.
It does not expressly require a particular dosage form or therapeutic indication.

The phrase “olanzapine pamoate salt” should be analyzed in view of the patent specification, chemical stoichiometry, prosecution history, and technical meaning of pamoate salts. The dependent claims show that the inventors contemplated both 1:1 olanzapine pamoate and 2:1 bis(olanzapine) pamoate forms.

A competing product containing olanzapine pamoate could potentially fall within claim 1 even if it used a different solvent or crystal form, provided it remained an olanzapine pamoate salt or solvate. Because the patent has expired, this historical breadth no longer creates an enforceable blocking position in the United States.

What solid forms are protected by claims 2 through 6?

Claims 2 through 6 narrow claim 1 to specific solvated forms identified by characteristic X-ray powder diffraction patterns.

Claim	Claimed form	Key structural limitation
2	Olanzapine pamoate dimethanolate	Characteristic XRPD pattern
3	Olanzapine pamoate monohydrate	Characteristic XRPD pattern
4	Bis(olanzapine) pamoate acetone solvate	Characteristic XRPD pattern
5	Bis(olanzapine) pamoate monohydrate solvate	Characteristic XRPD pattern
6	Olanzapine pamoate THF solvate	Characteristic XRPD pattern

The XRPD tables identify interplanar spacings and relative intensities. The strongest listed peaks include:

Claim 2: approximately 5.56 Å, 4.12 Å, and 4.03 Å.
Claim 3: approximately 5.38 Å, 10.76 Å, and 4.02 Å.
Claim 4: approximately 5.53 Å, 5.58 Å, and 8.88 Å.
Claim 5: approximately 4.19 Å, 4.85 Å, and 5.59 Å.
Claim 6: approximately 14.59 Å and 7.24 Å.

How do the XRPD limitations affect infringement analysis?

The XRPD limitations are identity limitations for particular solid forms. A product would not necessarily infringe claims 2 through 6 merely because it contained olanzapine pamoate. The relevant question would be whether the accused material has the claimed crystalline or solvated form and whether its diffraction pattern falls within the legally construed claim limitations.

The word “typical” in the patent’s XRPD descriptions does not automatically make every listed peak optional. Courts would examine the claim language, specification, prosecution history, and the meaning of the pattern as a whole. Small differences can result from instrumentation, sample preparation, hydration, solvent loss, polymorphic conversion, or peak measurement conditions. A solid-state comparison would normally require controlled analytical testing rather than reliance on a single peak.

Claim 6 is particularly narrow in practical terms because THF inclusion may be unstable during drying or storage. The dimethanolate, acetone-solvate, and THF-solvate claims also raise manufacturing and residual-solvent issues. A process that removes the solvent and produces a different anhydrous or polymorphic material may avoid a solvate-specific claim, although claim 1 would historically have presented a broader salt-level issue.

What does claim 7 protect?

Claim 7 covers:

“A method of treating an animal, including a human suffering from or susceptible to psychosis, acute mania or mild anxiety states which comprises administering a pharmaceutically effective amount” of a compound of claims 1 through 6.

Claim 7 is a method-of-treatment claim dependent on the composition claims. Its scope includes:

Treatment of existing psychosis.
Treatment of acute mania.
Treatment of mild anxiety states.
Treatment of an animal or human.
Administration of any compound falling within claims 1 through 6.
Administration of a pharmaceutically effective amount.

The claim does not specify oral, injectable, depot, intramuscular, subcutaneous, transdermal, or implant delivery. It also does not recite a dosing interval, concentration, pharmacokinetic target, excipient, or release rate.

A treatment method using olanzapine free base would not satisfy claim 7 because the method requires a compound covered by the pamoate composition claims. A method using a pamoate salt that falls within claim 1 could have raised infringement issues during the patent term even if the formulation or route differed from the examples in the specification.

When did U.S. Patent 6,169,084 lose exclusivity?

The patent lost enforceable exclusivity when its statutory term ended in 2019. The relevant term for a post-1995 U.S. patent is generally 20 years from the earliest effective nonprovisional U.S. filing date, subject to patent-term adjustment and any patent-term extension. U.S. 6,169,084 was issued in 2001, but the issue date did not establish the expiration date.

Event	Date or period
U.S. patent issuance	January 2, 2001
Statutory term	20 years from the relevant U.S. application filing date
Expected term end	2019
Current enforceability	Expired
Current blocking effect	None in the United States

The expiration of U.S. 6,169,084 does not invalidate other patents covering olanzapine formulations, manufacturing processes, delivery systems, or later-developed products. It removes the enforceable rights arising from this patent itself.

What patents protect olanzapine and Zyprexa?

The principal historical U.S. olanzapine patent estate included patents directed to the active compound and solid-state forms.

Patent	Subject matter	Strategic relevance
U.S. 5,229,382	Olanzapine and related thienobenzodiazepine compounds	Core compound protection
U.S. 5,736,541	Olanzapine crystalline form and related solid-state subject matter	Polymorph and product-form protection
U.S. 6,169,084	Olanzapine pamoate salts and solvates	Salt and solvate protection

U.S. 5,229,382 was the principal compound patent associated with olanzapine and Zyprexa. U.S. 5,736,541 addressed solid-state protection associated with olanzapine. U.S. 6,169,084 was narrower in commercial product relevance because it focused on pamoate salts rather than the approved oral olanzapine products. The main Zyprexa generic-entry dispute concerned the core olanzapine product and associated listed patents, not a marketed olanzapine pamoate product.

What is the Orange Book status of olanzapine pamoate?

Olanzapine pamoate is not the active ingredient in the principal FDA-approved Zyprexa products. FDA-approved olanzapine products include oral tablets, orally disintegrating tablets, and certain injectable products containing olanzapine, generally as the active pharmaceutical ingredient rather than as the pamoate salt.

The Orange Book listing system is product-specific. A patent covering an unapproved salt or a research-stage formulation does not automatically become an Orange Book-listed patent for an approved product. Patent listing requires a relationship to the approved drug substance, drug product, or approved method of use under FDA’s listing framework.

Question	Answer
Is olanzapine pamoate the active ingredient in Zyprexa tablets?	No
Does U.S. 6,169,084 automatically attach to all olanzapine products?	No
Is a pamoate patent necessarily listed for an olanzapine generic?	No
Does the patent create current Orange Book exclusivity?	No

FDA’s Orange Book identifies patents and exclusivity associated with approved drug products. The patent record and FDA product information should be reviewed separately because patent ownership and Orange Book listing are different legal and regulatory questions. [U.S. Food and Drug Administration, 2024a; U.S. Food and Drug Administration, 2024b]

Were Paragraph IV challenges directed to U.S. 6,169,084?

The patent was not the principal Orange Book barrier for generic olanzapine because it did not protect the approved olanzapine products as such. Paragraph IV litigation involving generic olanzapine generally centered on patents listed against the relevant Zyprexa reference products, especially patents covering olanzapine and its crystalline forms.

A Paragraph IV certification is available only in the context of an abbreviated new drug application addressing patents listed for the reference product. A patent covering an unapproved olanzapine pamoate salt would not ordinarily be subject to a Paragraph IV challenge in an ANDA for conventional olanzapine tablets unless that patent had been properly listed against the reference product.

After expiration, U.S. 6,169,084 could not support a current patent infringement action against a pamoate product. Historical litigation records should distinguish:

Litigation over core olanzapine.
Litigation over olanzapine polymorphs.
Litigation over formulation or dosage patents.
Litigation over pamoate salts or long-acting products.

Are biosimilar risks relevant to olanzapine pamoate?

No. Olanzapine is a chemically synthesized small molecule. Biosimilar pathways under the Public Health Service Act apply to biological products, not conventional small-molecule drugs. Competitive entry would occur through an ANDA, a 505(b)(2) application, or a conventional new drug application, depending on the product and development strategy.

A pamoate product could raise different regulatory questions from an olanzapine tablet. These could include:

Whether the pamoate salt is pharmaceutically equivalent to the reference product.
Whether the product is an injectable depot formulation.
Whether clinical studies are required under a 505(b)(2) pathway.
Whether the product has a different pharmacokinetic profile.
Whether residual solvent or solid-form controls are adequate.

Those regulatory issues are separate from the expired patent rights under U.S. 6,169,084.

What formulations and manufacturing processes remain relevant?

U.S. 6,169,084 does not claim a complete commercial formulation platform. The patent claims compounds and a treatment method. It does not expressly claim:

A specific tablet composition.
A depot microsphere.
A sustained-release injectable system.
A particular excipient combination.
A particle-size range.
A manufacturing crystallization process.
A residual-solvent specification.
A specific dose or dosing schedule.

The patent’s solid-state claims still have technical relevance because solvate control affects manufacturing, stability, assay, dissolution, and regulatory characterization. A developer seeking to commercialize an olanzapine pamoate product would need to distinguish the targeted form from the patented XRPD forms during development, although the expired status eliminates the patent as a current U.S. infringement barrier.

Separate later patents could protect a delivery system, depot formulation, particle engineering process, or method of administration. Those rights would require an independent patent-family search and cannot be inferred from U.S. 6,169,084.

How strong was the patent estate for olanzapine pamoate?

During its term, the estate had strong theoretical composition-of-matter protection but limited direct relevance to the approved Zyprexa market.

Factor	Assessment
Composition breadth	Strong at the salt level under claim 1
Solid-form protection	Narrower and analytically dependent
Method-of-use scope	Broad indications, but dependent on the pamoate compounds
Product-market relevance	Limited because marketed Zyprexa products used olanzapine, not olanzapine pamoate
Orange Book leverage	Limited or absent for conventional Zyprexa products
Current U.S. enforceability	None after expiration
Manufacturing barrier	Technical rather than legal after expiration
Generic-entry impact	Low for ordinary olanzapine products; historically more relevant to pamoate development

Claim 1 was the principal value driver. Claims 2 through 6 added form-specific protection but required more demanding proof of identity. Claim 7 extended the patent to therapeutic use, but its dependency on the claimed pamoate compounds narrowed its practical reach.

Which companies are challenging olanzapine patent protection?

Generic manufacturers challenged the broader olanzapine patent estate through ANDA filings and Paragraph IV certifications during the period when the core patents remained enforceable. Major generic companies active in olanzapine included Teva, Dr. Reddy’s Laboratories, and others participating in the U.S. generic market. Those challenges were directed principally to patents associated with approved olanzapine products.

There is no comparable current challenge necessary for U.S. 6,169,084 because the patent has expired. The commercial question for a new olanzapine pamoate entrant is now regulatory development, product differentiation, formulation performance, and any later patent rights, rather than this patent’s remaining term.

Did Eli Lilly license olanzapine pamoate rights?

The patent record identifies Eli Lilly and Company as the assignee. U.S. 6,169,084 itself does not establish a license grant, co-development transaction, or settlement agreement. Publicly available patent information should not be treated as evidence of commercial licensing terms.

The relevant commercial distinction is between:

Assignment recorded at the USPTO.
Patent licensing.
ANDA settlement agreements.
Authorized generic arrangements.
Product-specific co-development agreements.

Only the first is established directly by the patent record.

What generic launch risks exist for an olanzapine pamoate product?

The patent-specific generic-launch risk is now low because U.S. 6,169,084 has expired. The remaining barriers are primarily regulatory and technical.

A prospective entrant would evaluate:

Whether the product is an equivalent salt or a distinct active ingredient.
Whether the product is an oral or long-acting injectable formulation.
Whether an ANDA is legally available.
Whether a 505(b)(2) application is required.
Whether the selected solid form is stable and reproducible.
Whether residual methanol, acetone, THF, or water is controlled.
Whether later patents cover the formulation or delivery system.
Whether clinical evidence is required for a new pharmacokinetic profile.

The expired patent permits U.S. development without infringement exposure from this patent. It does not guarantee FDA approval or eliminate all patent risks associated with a new product configuration.

What geographic coverage does U.S. 6,169,084 provide?

The patent provides U.S. rights only. Corresponding foreign applications, national-stage patents, continuations, or divisionals must be assessed separately. Expiration in the United States does not establish the status of rights in Europe, Japan, Canada, China, or other jurisdictions.

For a multinational launch, the relevant analysis should separate:

U.S. composition rights.
Foreign salt and solvate patents.
Foreign formulation patents.
Regulatory data exclusivity.
Local patent-term adjustments.
Patent-term extensions.
National litigation and settlement records.

The U.S. patent’s expiration cannot be exported automatically to foreign markets.

Key Takeaways

U.S. 6,169,084 claims olanzapine pamoate salts and solvates.
Claim 1 is the broad composition claim.
Claims 2 through 6 narrow the invention to five XRPD-characterized solid forms.
Claim 7 covers treatment of psychosis, acute mania, and mild anxiety states using the claimed compounds.
The patent does not cover olanzapine free base generally.
It was not the primary patent protecting conventional Zyprexa tablets.
Olanzapine pamoate was not the active ingredient in the principal FDA-approved Zyprexa products.
The patent’s U.S. term ended in 2019.
No current Paragraph IV or Orange Book barrier arises from this expired patent.
Biosimilar analysis is not applicable because olanzapine is a small molecule.
Current commercial risks concern regulatory classification, solid-form control, delivery technology, and later patents.

FAQs

Can a company market olanzapine pamoate in the United States after U.S. 6,169,084 expired?

Yes, the expired patent no longer blocks U.S. commercialization. The product would still require an appropriate FDA approval pathway and compliance with any later enforceable patent rights.

Does olanzapine pamoate have the same regulatory status as olanzapine hydrochloride or olanzapine free base?

No. A different salt can raise questions about pharmaceutical equivalence, active-ingredient characterization, bioavailability, and the appropriate FDA application pathway.

Are the XRPD peak tables in claims 2 through 6 interchangeable?

No. Each claim identifies a different solid form. The peak sets should be analyzed as separate patterns, not as a single interchangeable fingerprint.

Could a new olanzapine depot injection infringe U.S. 6,169,084?

The expired patent cannot support a current U.S. infringement claim. During its term, a depot injection containing a covered olanzapine pamoate form could have presented composition or method-of-use issues.

Does expiration of U.S. 6,169,084 eliminate all olanzapine pamoate patent risk worldwide?

No. The patent is U.S.-specific. Foreign family members, later patents, formulation patents, delivery patents, and process patents require separate jurisdiction-by-jurisdiction review.

References

Eli Lilly and Company. (2001). Olanzapine pamoate (U.S. Patent No. 6,169,084). United States Patent and Trademark Office.
Eli Lilly and Company. (1993). Thienobenzodiazepine derivatives (U.S. Patent No. 5,229,382). United States Patent and Trademark Office.
Eli Lilly and Company. (1998). Olanzapine (U.S. Patent No. 5,736,541). United States Patent and Trademark Office.
U.S. Food and Drug Administration. (2024a). Approved drug products with therapeutic equivalence evaluations. FDA.
U.S. Food and Drug Administration. (2024b). Approved drug product label: Zyprexa (olanzapine). FDA.
United States Patent and Trademark Office. (2024). Patent term adjustment and patent term expiration provisions. USPTO.

Country	Patent Number	Estimated Expiration	Supplementary Protection Certificate	SPC Country	SPC Expiration
Argentina	018171	⤷ Start Trial
Austria	267602	⤷ Start Trial
Austria	359793	⤷ Start Trial
>Country	>Patent Number	>Estimated Expiration	>Supplementary Protection Certificate	>SPC Country	>SPC Expiration

Details for Patent: 6,169,084

Summary for Patent: 6,169,084