United States Patent 5,972,919: Scope, Claims, Expiration, and Budesonide-Formoterol Patent Landscape

U.S. Patent 5,972,919 covers pharmaceutical products and inhaled treatment methods combining formoterol, or a physiologically acceptable salt or solvate, with budesonide at a formoterol-to-budesonide molar ratio of 1:4 to 1:70. The patent also claims specific dosage ranges, dry-powder formulations, lactose carriers, formoterol fumarate dihydrate, inhaler devices, nebulizers, and simultaneous, mixed, sequential, or separate administration.

The patent is expired. Its statutory patent term ended in February 2017 based on the relevant priority and filing history. It no longer creates a prospective U.S. patent barrier to generic budesonide-formoterol products. Its commercial importance was concentrated in the early Symbicort development and exclusivity period.

What does U.S. Patent 5,972,919 protect?

The patent protects a defined combination of two active pharmaceutical ingredients:

Formoterol, including a physiologically acceptable salt or solvate
Budesonide
A molar ratio of formoterol component to budesonide component from 1:4 to 1:70

The claims cover both composition and treatment concepts. The central limitation is the combination of the active ingredients within the specified molar range.

Claim group	Subject matter	Principal limitation
Claim 1	Medicament	Formoterol salt or solvate plus budesonide at a 1:4 to 1:70 molar ratio
Claim 2	Pharmaceutical composition	Same active ingredients and ratio, with a pharmaceutically acceptable carrier
Claims 3-5	Treatment method	Inhaled treatment of asthma and inflammatory respiratory disorders
Claims 6-8	Formulation and chemical form	Dry powder, formoterol fumarate dihydrate
Claims 9-12	Delivery systems	Dry-powder inhaler, Turbuhaler, metered-dose inhaler, or specified formoterol form
Claims 13-14	Carrier and dosage form	Lactose carrier and dosage-unit form
Claim 15	Nebulizer use	Administration by nebulizer
Claims 16-19	Administration pattern	Simultaneous, admixture, sequential, or separate administration

The claim text supplied for claim 3 states a range of “1.70.” In context, this is almost certainly a transcription of “1:70,” consistent with claim 1 and the dependent claims. The legally controlling claim text is the issued patent document.

How broad is the formoterol-budesonide ratio limitation?

The 1:4 to 1:70 molar ratio is the principal composition limitation. A product outside that range would not literally satisfy the ratio limitation, although infringement analysis could still consider claim construction and the doctrine of equivalents for an unexpired patent.

The ratio is based on molecular amounts, not simply the mass ratio printed on a product label. For commercial Symbicort strengths, the ratio generally falls within the claimed range when calculated using the formoterol component and budesonide molecular weights.

Approximate ratio examples are:

Product strength per actuation	Approximate formoterol-to-budesonide molar ratio
4.5 mcg formoterol with 80 mcg budesonide	Approximately 1:14
4.5 mcg formoterol with 160 mcg budesonide	Approximately 1:28

The exact calculation depends on whether the analysis uses formoterol base, formoterol fumarate, or the labeled salt-equivalent convention. Claim 7 and related claims expressly identify formoterol fumarate dihydrate, which is the form used in commercial combination products.

Does the claim cover every budesonide-formoterol product?

No. The claims require the specified ratio and, for dependent claims, additional limitations such as:

Dry powder
Formoterol fumarate dihydrate
Lactose carrier
A dosage-unit form
Delivery through a Turbuhaler, metered-dose inhaler, or nebulizer
A particular administration sequence

The independent claims are broader than the dependent claims. Claim 1 does not expressly require an inhaler, carrier, or dry-powder formulation. Claim 2 requires a pharmaceutically acceptable carrier. Claims 3 through 5 require inhaled administration and treatment of asthma or another inflammatory respiratory disorder.

What formulations are protected by U.S. Patent 5,972,919?

The patent reaches several formulation categories.

Dry-powder formulations

Claim 6 narrows the medicament to a dry-powder form. Claim 9 separately narrows the treatment method to administration from a dry-powder inhaler. Claim 13 identifies lactose as the carrier, a conventional excipient in dry-powder inhalation products.

A dry-powder product containing formoterol fumarate dihydrate, budesonide, and lactose would have been a strong target for claims 1, 2, 6, 7, 8, 13, and 14 if the ratio and other limitations were met during the patent term.

Metered-dose inhalers

Claim 11 covers administration from a metered-dose inhaler. The claim does not require a dry powder, so it addresses a different delivery platform from claim 9.

A metered-dose product could fall within claim 3 and claim 11 if it delivered the required active ingredients by inhalation at the claimed ratio. The patent language supplied does not require a particular propellant, suspension system, particle engineering approach, or valve design.

Nebulizer formulations

Claim 15 covers treatment by nebulizer. The claim does not require the two components to be chemically combined in a single formulation. Claims 16 through 19 expressly recognize several administration patterns:

Simultaneous administration
Administration in admixture
Sequential administration
Separate administration

This drafting gives the method claims broader product-configuration coverage than a claim limited to a single fixed-dose combination can provide.

What dosage ranges does the patent claim?

Claims 4 and 5 provide narrower treatment ranges.

Claim	Formoterol component	Budesonide
Claim 4	6-100 mcg per day	50-4,800 mcg per day
Claim 5	6-48 mcg per day	100-1,600 mcg per day

Claim 5 is narrower and likely more commercially aligned with ordinary maintenance-dose use. The claimed daily ranges are independent limitations in the method claims. A treatment regimen outside those ranges may avoid claims 4 and 5 while remaining potentially relevant to claim 3 if the ratio and disease-treatment limitations are satisfied.

What is the scope of the method-of-use claims?

Claims 3 through 5 are method-of-treatment claims for:

Asthma
Other inflammatory respiratory disorders
Inhaled administration
Effective amounts of formoterol and budesonide
The specified molar ratio

Claims 16 through 19 broaden the administration configurations. A physician or patient regimen involving separate inhalers could fall within the language of claim 19 if the other limitations were satisfied. Claim 17 addresses an admixture, while claim 18 covers sequential dosing.

The claims do not appear limited to a particular severity classification, age group, treatment line, exacerbation status, or dosing frequency. They also do not require a specific pharmacodynamic outcome beyond treatment with effective amounts.

When did U.S. Patent 5,972,919 lose exclusivity?

U.S. Patent 5,972,919 issued on October 26, 1999. Its patent term ran approximately 20 years from the relevant nonprovisional filing or priority framework and ended in February 2017. The U.S. Patent and Trademark Office identifies the patent as expired. [1]

Event	Date
U.S. application filing	February 1997
Patent issued	October 26, 1999
Approximate statutory expiration	February 2017
Current status	Expired
Prospective enforceability	None

The patent’s expiration means that a current product launch does not require a license from the patent owner for the claims of U.S. Patent 5,972,919. Expiration does not erase historical infringement exposure for conduct occurring before expiration, but it removes the patent as a current injunction or launch-barrier asset.

What is the Orange Book status of U.S. Patent 5,972,919?

The patent was associated with the early U.S. patent estate for AstraZeneca’s Symbicort product, which combines budesonide and formoterol fumarate dihydrate. The relevant FDA product is Symbicort, marketed in 80/4.5 mcg and 160/4.5 mcg strengths under NDA 021929. [2]

The current commercial question is not whether the patent once supported an Orange Book listing. The decisive point is that the patent has expired. An expired Orange Book patent does not support a current patent-based delay of an ANDA launch.

Orange Book analysis must distinguish among:

Expired patents
Unexpired formulation or device patents
Method-of-use patents
Regulatory exclusivity
Patent certifications submitted by an ANDA applicant

U.S. Patent 5,972,919 is in the first category. It should not be treated as an active Orange Book barrier to generic budesonide-formoterol approval.

Which products competed with the patented combination?

The patent covered the budesonide-formoterol combination rather than the entire long-acting beta agonist/inhaled corticosteroid market.

Product	Inhaled corticosteroid	Long-acting bronchodilator	Sponsor or principal marketer	Relationship to the patent
Symbicort	Budesonide	Formoterol	AstraZeneca	Direct commercial product
Dulera	Mometasone	Formoterol	Organon/Merck lineage	Same LABA/ICS class, different corticosteroid
Advair	Fluticasone propionate	Salmeterol	GSK	Same class, different actives
Breo Ellipta	Fluticasone furoate	Vilanterol	GSK	Same class, different actives
Breyna	Budesonide	Formoterol	Viatris/Kindeva lineage	Generic or authorized-generic competition to Symbicort
Airsupra	Budesonide	Albuterol	AstraZeneca	Different bronchodilator and indication

Dulera, Advair, and Breo Ellipta do not fall within the literal active-ingredient combination of the patent because they use different corticosteroid and/or bronchodilator molecules.

Which companies challenged Symbicort patents?

Generic competition emerged through ANDA litigation and FDA approval activity involving budesonide-formoterol products. Viatris and Kindeva received FDA approval for Breyna, a generic equivalent to Symbicort, in 2022. [3]

The critical legal distinction is that later generic litigation focused on the remaining unexpired Symbicort patent estate, not on U.S. Patent 5,972,919 as a live patent. A Paragraph IV certification against an expired patent would not create the same launch risk as a certification against an unexpired Orange Book-listed patent.

What was the Paragraph IV risk?

For an unexpired Orange Book patent, a Paragraph IV certification can trigger patent litigation and a potential 30-month stay of ANDA approval under the Hatch-Waxman framework. [4] For U.S. Patent 5,972,919, expiration eliminates the forward-looking benefit of that mechanism.

The commercial risk therefore shifted from the original combination patent to later patents covering matters such as:

Specific inhaler devices
Particle-size distributions
Formulation architecture
Manufacturing processes
Dose counter or actuator systems
Other product-specific features

A generic manufacturer could still face litigation based on those later patents even after the basic combination patent expired.

How strong was the patent estate for the commercial product?

U.S. Patent 5,972,919 was commercially significant because it claimed the core active combination and several clinically relevant administration formats. Its claim strength can be assessed across four dimensions.

Dimension	Assessment
Chemical scope	Moderate to broad; covers formoterol salts or solvates with budesonide
Ratio scope	Defined but commercially relevant; 1:4 to 1:70 captures common strengths
Delivery scope	Broad across dry powder, metered-dose inhaler, nebulizer, simultaneous, and sequential use
Current enforceability	None; patent expired

The patent was stronger against a fixed-dose budesonide-formoterol product that used the claimed ratio than against an alternative regimen using different actives, a different ratio, or a non-inhaled route. Its method claims also depended on proving actual administration and the claimed therapeutic use.

Because the claims include multiple dosage and delivery alternatives, an accused product might satisfy some claims while avoiding others. Claim 1, for example, does not require lactose or a particular inhaler, while claims 13 and 14 do.

Are there biosimilar risks for this patent?

No. Biosimilar risk is not the relevant framework because formoterol and budesonide are small-molecule drugs, not biological products regulated through the Biologics Price Competition and Innovation Act pathway.

Competition proceeds through the ANDA pathway for chemically equivalent generic products. FDA approval depends on pharmaceutical equivalence, bioequivalence, quality, device considerations, and applicable patent certifications. [4]

What manufacturing and intellectual-property barriers remain?

The expired patent does not eliminate all barriers to commercial entry. Remaining barriers can include:

Demonstrating in vitro and in vivo equivalence for an inhaled product
Matching emitted dose and fine-particle fraction
Controlling blend uniformity in a dry-powder formulation
Managing formoterol fumarate dihydrate stability
Establishing device performance and dose delivery
Addressing residual unexpired patents
Reproducing commercial-scale manufacturing controls
Obtaining FDA approval for the specific inhaler presentation

For inhaled products, device and formulation equivalence can be as important commercially as the expired composition patent. A generic applicant may avoid the expired patent yet still need to design around later device or manufacturing claims.

What licensing deals affect U.S. Patent 5,972,919?

The patent was part of AstraZeneca’s proprietary budesonide-formoterol development and commercial platform. No separate license is required today to practice the expired claims in the United States.

Commercial arrangements involving generic Symbicort products may concern manufacturing, marketing, device supply, authorized-generic rights, or settlements relating to other patents. Those arrangements should not be attributed to U.S. Patent 5,972,919 without a specific agreement identifying that patent.

What generic launch scenarios exist now?

The current U.S. launch analysis is straightforward:

Scenario	Effect of U.S. Patent 5,972,919
Generic fixed-dose budesonide-formoterol matching the claimed ratio	No current barrier from this patent
Generic dry-powder product using formoterol fumarate dihydrate	No current barrier from this patent
Separate budesonide and formoterol inhalers	No current barrier from this patent
Nebulized combination	No current barrier from this patent
Product using a different LABA or corticosteroid	Outside the core active combination
Product challenged by later device patents	Potential risk remains outside this patent

The principal current competition is generic or authorized-generic budesonide-formoterol, including Breyna. Symbicort remains the reference product, but U.S. Patent 5,972,919 no longer supports exclusivity.

What is the geographic coverage of the patent?

U.S. Patent 5,972,919 provided protection only in the United States. International protection would depend on separate national or regional family members, such as European, Canadian, Japanese, or other corresponding patents.

Expiration in the United States does not establish expiration dates in other jurisdictions. National patent terms, supplementary protection certificates, patent-term adjustments, maintenance-fee events, and claim scope can differ. A global freedom-to-operate analysis must therefore treat the U.S. patent as one jurisdiction-specific asset.

Key Takeaways

U.S. Patent 5,972,919 covers budesonide combined with formoterol or a pharmaceutically acceptable salt or solvate.
The central ratio is formoterol component to budesonide component of 1:4 to 1:70.
The claims cover medicaments, pharmaceutical compositions, inhaled treatment methods, dry powders, lactose carriers, formoterol fumarate dihydrate, inhalers, nebulizers, and multiple administration patterns.
Commercial Symbicort strengths fall within the claimed ratio range.
The patent expired in approximately February 2017.
It is no longer a current U.S. patent barrier to generic entry.
Biosimilar analysis does not apply because the products are small-molecule drugs.
Current entry risk depends on later patents, inhaler-device rights, formulation claims, manufacturing patents, FDA requirements, and commercial execution.
Breyna demonstrates that U.S. generic competition to Symbicort has entered the market.
The patent’s historical value was concentrated in protecting the core budesonide-formoterol combination during the early Symbicort exclusivity period.

FAQs About U.S. Patent 5,972,919

Does U.S. Patent 5,972,919 cover Symbicort?

Yes. Its active-ingredient and molar-ratio claims cover the budesonide-formoterol combination used in Symbicort, subject to the precise claim limitations.

Is U.S. Patent 5,972,919 still enforceable?

No. The patent expired in approximately February 2017 and does not create prospective U.S. patent exclusivity.

Does the patent cover formoterol fumarate dihydrate?

Yes. Claims 7, 8, and 12 specifically recite formoterol fumarate dihydrate.

Does the patent cover separate budesonide and formoterol inhalers?

The method claims expressly include separate and sequential administration. The product claims require a medicament or composition containing both active components.

Can a generic manufacturer rely on the expiration of this patent?

Yes, as to this patent. The manufacturer must still evaluate later patents, FDA requirements, device rights, formulation claims, and any other applicable exclusivity.

Is a 1:70 ratio limitation a mass ratio or a molar ratio?

It is a molar ratio. The relevant calculation must account for the molecular identity and salt or solvate form of the formoterol component.

References

United States Patent and Trademark Office. (1999). U.S. Patent No. 5,972,919, Pharmaceutical composition comprising formoterol and budesonide.
U.S. Food and Drug Administration. (2006). Symbicort inhalation aerosol, budesonide and formoterol fumarate dihydrate, NDA 021929. Drugs@FDA.
U.S. Food and Drug Administration. (2022). Breyna, budesonide and formoterol fumarate dihydrate inhalation aerosol. Drugs@FDA.
U.S. Food and Drug Administration. (2023). Approved drug products with therapeutic equivalence evaluations. Orange Book.

Foriegn Application Priority Data
Foreign Country	Foreign Patent Number	Foreign Patent Date
	91311761	Dec 18, 1991

Country	Patent Number	Estimated Expiration	Supplementary Protection Certificate	SPC Country	SPC Expiration
European Patent Office	0613371	⤷ Start Trial	CA 2002 00019	Denmark	⤷ Start Trial
European Patent Office	0613371	⤷ Start Trial	SPC/GB02/033	United Kingdom	⤷ Start Trial
European Patent Office	0613371	⤷ Start Trial	SPC016/2002	Ireland	⤷ Start Trial
European Patent Office	0613371	⤷ Start Trial	2002C/022	Belgium	⤷ Start Trial
>Country	>Patent Number	>Estimated Expiration	>Supplementary Protection Certificate	>SPC Country	>SPC Expiration

Details for Patent: 5,972,919

Summary for Patent: 5,972,919