United States Patent 6,987,101: Drospirenone, PMDD Treatment Claims, Expiration, and Patent Landscape

US Patent 6,987,101 covers methods of treating premenstrual dysphoric disorder, or PMDD, with drospirenone alone or with an estrogen. Its broadest claim reaches drospirenone monotherapy, while dependent claims narrow the method by estrogen identity, dose, timing, route, and administration schedule. The patent was assigned to Schering AG, later part of Bayer, and its enforceable term has expired based on the statutory patent term.

The patent does not claim drospirenone as a chemical compound, a tablet formulation, a manufacturing process, or contraception generally. Its commercial significance was concentrated in PMDD treatment claims involving drospirenone-containing products, particularly Yaz and related products.

What does US Patent 6,987,101 cover?

US 6,987,101 covers a therapeutic use of drospirenone for PMDD. Claim 1 is the key independent claim:

A method of treating premenstrual dysphoric disorder by administering a therapeutically effective amount of drospirenone.

Claim 2 adds an estrogen to the drospirenone treatment. The remaining claims specify particular estrogens, dosages, dosing schedules, routes, and patterns of administration.

Patent identification and prosecution data

Field	Data
US patent	6,987,101
Title	Use of drospirenone for treating premenstrual dysphoric disorder
Patent type	Method-of-treatment patent
Applicant/assignee	Schering AG
Current commercial successor	Bayer AG
Priority date	February 28, 2000
US grant date	January 17, 2006
Earliest statutory expiration	February 28, 2021
Primary therapeutic area	Premenstrual dysphoric disorder
Active ingredient	Drospirenone
Estrogen combinations	Ethinylestradiol, estradiol, estradiol valerate, other estradiol esters, and specified estrogen classes
Status	Expired by patent term

The patent term is generally 20 years from the earliest effective nonprovisional filing date under 35 U.S.C. § 154. The patent’s relevant term therefore ran from its 2000 priority period to 2021, subject to any applicable patent-term adjustment or other USPTO term calculation.[1][2]

What is the scope of independent claim 1?

Claim 1 is broad in therapeutic and dosing terms. It requires four principal elements:

A patient in need of treatment.
A diagnosis or condition characterized as PMDD.
Administration of drospirenone.
A therapeutically effective amount.

Claim 1 does not expressly require:

An estrogen;
Oral administration;
Continuous dosing;
Luteal-phase dosing;
A particular tablet or dosage form;
A particular drospirenone dose;
Contraceptive use;
A specified treatment duration.

The claim therefore covers drospirenone monotherapy when used to treat PMDD, subject to the legal requirements for direct infringement of a method claim. A product label or prescribing practice that specifically directs drospirenone treatment for PMDD would have been more significant than a product merely containing drospirenone for contraception.

What is excluded from claim 1?

Claim 1 does not independently claim every use of drospirenone. It does not cover:

Contraception without PMDD treatment;
Treatment of acne;
Treatment of endometriosis;
Treatment of menstrual irregularity unless the use also satisfies PMDD treatment;
Drospirenone products used outside the claimed therapeutic purpose;
The drospirenone molecule itself;
A formulation independent of the PMDD method.

The infringement analysis turns on the actual or induced use of the product, not merely on the presence of drospirenone.

What do claims 2 through 7 protect?

Claims 2 through 7 cover combinations of drospirenone with estrogen.

Claim 2 requires:

Drospirenone;
An estrogen;
Treatment of PMDD.

Claims 3 through 7 narrow the estrogen component.

Claim	Claimed subject matter
2	Drospirenone plus an estrogen
3	Synthetic estrogen
4	Ethinylestradiol
5	Estrogen sulfamate
6	Natural estrogen
7	Estradiol, estradiol valerate, or another estradiol ester

Claim 4 is the commercially important combination claim because it reaches drospirenone plus ethinylestradiol, the active hormonal combination in Yaz and related products. The claim does not require a particular ratio, tablet architecture, inactive ingredient, package configuration, or 24/4 regimen unless another claim limitation applies.

Does claim 4 cover Yaz?

Claim 4 is directed to a method of treating PMDD with drospirenone and ethinylestradiol. A Yaz regimen could fall within the claim if the product and labeling satisfy the remaining elements, including treatment of PMDD and administration of therapeutically effective amounts.

Claim 4 does not by itself claim the Yaz composition as a product. Separate formulation, composition, dosage-regimen, and contraceptive patents addressed other aspects of drospirenone/ethinylestradiol products.

What dosing schedules are protected?

Claims 8 through 21 create several dosing-specific branches.

Luteal-phase dosing

Claim 8 covers administering drospirenone only during the luteal phase of the menstrual cycle. Claim 9 narrows that schedule to administration from day 10 through day 28.

This is narrower than claim 1 because it requires a specific timing relationship to the menstrual cycle. A continuous regimen would not satisfy claim 8 or claim 9, although it could fall within claim 1 or another applicable claim.

Drospirenone dose

Claim 10 covers a daily drospirenone dose of:

At least 0.5 mg; and
Less than 5 mg.

Claim 16 narrows that range to 1.0 mg through 4.0 mg daily.

The 3 mg drospirenone dose used in Yaz falls within claim 16 when the remaining claim elements are met.

Estrogen dose

Claim 11 covers ethinylestradiol at 0.010 mg to 0.05 mg daily. That range includes the 0.020 mg ethinylestradiol dose used in Yaz.

Claim 12 covers estradiol at 1.0 mg to 3.0 mg daily.

Administration pattern

Claims 13 and 14 require the gestagen and estrogen to be administered together and orally.

Claims 19 through 21 cover:

Continuous administration;
Sequential administration; or
Cyclical administration.

These claims create coverage across several hormonal treatment designs. A product can satisfy a regimen claim only when its actual or directed use meets the specified administration pattern.

What formulations are protected by US 6,987,101?

US 6,987,101 is not a conventional formulation patent. It does not principally claim:

A particular tablet composition;
A particular excipient;
A dissolution profile;
A coated tablet;
A sustained-release matrix;
A blister-pack design;
A specific particle size;
A manufacturing process.

Its formulation relevance is indirect. An oral drospirenone/ethinylestradiol tablet may be used in a manner that satisfies the method claims, but the patent does not make every such tablet an infringing product regardless of use.

The patent’s formulation-related exposure was therefore dependent on:

The approved indication;
Product labeling;
Physician prescribing;
Generic labeling;
Evidence of induced PMDD use;
The expiration status of the method claims.

What is the relationship between the patent and Yaz?

Yaz contains drospirenone and ethinylestradiol. The FDA approved Yaz in 2006 for contraception and later approved PMDD-related labeling for women who choose oral contraception.[3]

Product	Active ingredients	Relevant PMDD relationship
Yaz	Drospirenone 3 mg plus ethinylestradiol 0.02 mg	FDA-approved PMDD indication in an oral contraceptive population
Yasmin	Drospirenone 3 mg plus ethinylestradiol 0.03 mg	Drospirenone/ethinylestradiol product, but PMDD scope depends on labeling
Beyaz	Drospirenone, ethinylestradiol, and levomefolate	PMDD-related use may implicate the same therapeutic concept
Slynd	Drospirenone 4 mg	Drospirenone-only contraceptive product; no reliance on a drospirenone/ethinylestradiol combination
Generic Yaz products	Drospirenone plus ethinylestradiol	PMDD exposure depends on approved labeling and patent status

The 3 mg drospirenone dose in Yaz is within the numerical range of claims 10 and 16. The 0.02 mg ethinylestradiol dose is within claim 11. Yaz therefore corresponds closely to the patent’s narrower dose and combination claims when used for PMDD.

What was the Orange Book status of US 6,987,101?

The FDA Orange Book lists patents submitted by NDA applicants for approved drug products when the patents meet the statutory listing criteria. Method-of-use patents may be listed when they claim an approved use of the drug product.[4]

The patent’s practical Orange Book significance was tied to PMDD labeling for drospirenone/ethinylestradiol products. A generic applicant could address an Orange Book-listed method patent through:

A Paragraph III certification, agreeing not to market until patent expiry;
A Paragraph IV certification, asserting that the patent is invalid, unenforceable, or not infringed;
A section viii statement, carving out the patented use from the proposed label.

Because US 6,987,101 has expired, it no longer creates a current bar to FDA approval or commercial launch. Any historical Orange Book listing did not preserve exclusivity after expiration.

Does the patent block generic contraception?

No. The patent was directed to PMDD treatment, not contraception generally. A generic applicant could seek approval for contraception with a label that omitted PMDD if the relevant patent and regulatory requirements permitted a section viii carve-out.

The commercial risk depended on whether the generic label:

Included PMDD;
Promoted PMDD;
Reproduced a patented indication;
Was accompanied by instructions that induced PMDD use.

When did US 6,987,101 lose exclusivity?

The patent’s ordinary term expired in 2021 based on the February 28, 2000 priority date. The patent therefore no longer provides enforceable exclusivity for:

Drospirenone monotherapy for PMDD;
Drospirenone plus ethinylestradiol for PMDD;
The specified drospirenone and estrogen dose ranges;
Luteal-phase dosing;
Continuous, sequential, or cyclic administration;
The claimed oral administration methods.

Patent expiration is separate from FDA regulatory exclusivity. FDA marketing exclusivity, if available for an approved product or indication, is governed by the Food, Drug, and Cosmetic Act and does not extend the patent term.[4][5]

Which patents competed with US 6,987,101?

The drospirenone/ethinylestradiol estate included several patent categories.

Drospirenone compound patents

Earlier patents protected drospirenone and related steroid chemistry. Those patents were directed to the active pharmaceutical ingredient or its chemical class rather than specifically to PMDD treatment. Their terms expired before or around the period when drospirenone contraceptive products reached generic competition.

Combination and composition patents

Other patents addressed the combination of drospirenone with ethinylestradiol, including:

Tablet compositions;
Hormone ratios;
Oral contraceptive use;
Stability;
Packaging;
Delivery and dosage characteristics.

These patents were more relevant to generic product approval than US 6,987,101 when the proposed product was a drospirenone/ethinylestradiol tablet.

Regimen patents

Regimen patents covered shortened hormone-free intervals, including 24 active tablets followed by a four-day inactive interval. Such patents were commercially important for Yaz-type products because the dosing schedule differed from earlier 21/7 oral contraceptive regimens.

PMDD method patents

US 6,987,101 occupied the PMDD-specific portion of the estate. Its distinctive limitation was the use of drospirenone to treat PMDD, with optional estrogen and detailed dosing alternatives.

What Paragraph IV challenges affected the drospirenone patent estate?

Generic applicants challenged patents covering Yaz and related products through ANDA litigation. The most commercially important disputes involved Bayer and generic manufacturers such as Barr Pharmaceuticals and Teva over patents associated with drospirenone/ethinylestradiol products.

The litigation landscape included challenges to formulation, composition, and regimen patents, not only PMDD treatment claims. Generic applicants commonly used two routes:

Paragraph IV challenges to patents they considered invalid, unenforceable, or not infringed.
Section viii carve-outs for indications that they did not seek to market.

For US 6,987,101, a Paragraph IV challenge would have focused on method-of-treatment issues, including:

Whether PMDD treatment with drospirenone was novel;
Whether the claimed use was obvious in view of prior hormonal treatments;
Whether the specification adequately supported the full scope of the estrogen and dosing claims;
Whether the generic label induced infringement;
Whether the claims were definite and properly enabled.

Once the patent expired in 2021, a Paragraph IV challenge to that patent ceased to have meaningful launch-blocking value.

How strong were the patent claims?

The patent had a mixed strength profile.

Claim group	Breadth	Main vulnerability or limitation
Claim 1, drospirenone monotherapy	Broad	Requires PMDD treatment and a therapeutically effective amount
Claim 2, drospirenone plus estrogen	Broad combination claim	Requires estrogen coadministration
Claims 3-7, estrogen subclasses	Medium	Chemical classification and claim-construction issues
Claims 8-9, luteal dosing	Narrow	Easier design-around through continuous or different-cycle dosing
Claims 10 and 16, drospirenone dose	Medium	Numerical range limitations
Claim 11, ethinylestradiol dose	Medium	Closely maps to commercial Yaz dosing
Claim 12, estradiol dose	Narrower	Limited to specified natural estrogen dosing
Claims 13-14, together and orally	Narrow	Potential separation or route design-arounds
Claims 19-21, administration pattern	Narrow to medium	Scope depends on interpreting continuous, sequential, and cyclic use

Claim 1 had the greatest theoretical reach because it did not require estrogen, a specific dose, or a specific administration schedule. Claims 4, 11, and 16 had greater commercial relevance because they aligned with a drospirenone/ethinylestradiol product and common dose strengths.

The main enforcement challenge for a method patent was proof of the intended use. A generic product labeled only for contraception would present a different risk profile from a product expressly labeled for PMDD.

What generic launch scenarios existed?

Before expiration, the principal scenarios were:

Generic contraception with PMDD carve-out

A generic manufacturer could seek approval for contraception while omitting the PMDD indication. This reduced direct label-based infringement risk and allowed earlier entry if other patents did not block launch.

Generic product with PMDD indication after patent expiry

After February 2021, a generic manufacturer could pursue PMDD labeling without US 6,987,101 creating a patent barrier.

At-risk launch after Paragraph IV certification

A company could launch before final patent resolution after making a Paragraph IV certification, subject to litigation risk, potential injunctions, damages, and market-share consequences.

Product-specific entry

A generic could enter with a product matching the drospirenone/ethinylestradiol formulation but omit protected indications. The economic value of the carve-out depended on the proportion of prescriptions associated with PMDD rather than contraception.

What licensing deals affected the patent?

The relevant corporate transfer was the consolidation of Schering’s pharmaceutical assets into Bayer. Bayer acquired Schering AG in 2006, and Bayer became the principal commercial owner of the Yaz and Yasmin franchise.[6]

No separate public license is required to explain the ownership transition for US 6,987,101. The patent’s commercial rights moved through corporate acquisition rather than a publicly identified third-party license directed specifically to this patent.

What manufacturing and IP barriers remain?

US 6,987,101 creates no current manufacturing barrier because it is expired. Historical barriers came from other parts of the product estate:

Reproducing the approved drospirenone/ethinylestradiol composition;
Meeting ANDA bioequivalence requirements;
Demonstrating product stability;
Addressing crystalline or solid-state characteristics;
Navigating formulation and regimen patents;
Establishing a legally compliant label;
Avoiding induced infringement during the pre-expiration period.

Drospirenone manufacturing can also involve process controls and impurity specifications, but those issues are separate from the expired PMDD method claims unless a live process patent applies.

How does US 6,987,101 compare with formulation and regimen patents?

Issue	US 6,987,101	Formulation patent	Regimen patent
Patent subject	PMDD treatment method	Product or composition	Administration schedule
Requires PMDD use	Yes	Usually no	Sometimes
Requires estrogen	Only dependent combination claims	Depends on claim	Depends on claim
Covers drospirenone molecule	No	Usually no, unless composition claim	No
Covers tablet structure	No	Yes, if claimed	No
Covers 24/4 dosing	Only if covered by a relevant administration claim	No	Typically yes
Current status	Expired	Must be checked patent by patent	Must be checked patent by patent
Main generic risk	Label and induced-use exposure	Product approval and infringement	Label and regimen instructions

What is the current competitive landscape?

The competitive market includes:

Branded drospirenone/ethinylestradiol products;
Generic equivalents of Yaz;
Drospirenone-only contraception;
Other combined oral contraceptives;
SSRIs and other nonhormonal PMDD therapies;
Hormonal products using different progestins;
Products approved for contraception but not PMDD.

US 6,987,101 no longer differentiates Bayer’s products from generic products. The principal competitive barriers are now regulatory approval, clinical positioning, manufacturing cost, supply reliability, brand recognition, and any unexpired product-specific patents outside this patent.

What revenue exposure did the patent create?

The patent’s revenue exposure was tied to the PMDD component of drospirenone/ethinylestradiol sales. The larger Yaz franchise generated revenue from contraception, while PMDD represented a narrower approved-use segment.

The patent did not protect all Yaz revenue because:

Claim 1 required PMDD treatment;
Claims 2 through 21 added further limitations;
Contraceptive use alone was outside the core claim language;
Generic products could pursue indication carve-outs;
Other patents independently governed formulation and regimen issues.

The patent’s greatest historical value was therefore defensive. It supported the branded product’s PMDD indication and increased the complexity of generic label design and litigation strategy.

Key Takeaways

US 6,987,101 is a PMDD method-of-treatment patent centered on drospirenone.
Claim 1 covers drospirenone monotherapy for PMDD.
Claim 4 covers drospirenone plus ethinylestradiol for PMDD.
Claims 10, 11, and 16 encompass common Yaz strengths of 3 mg drospirenone and 0.02 mg ethinylestradiol.
Claims 8 and 9 cover luteal-phase schedules, while claims 19 through 21 cover continuous, sequential, and cyclic administration.
The patent does not claim drospirenone, a tablet formulation, a manufacturing process, or contraception generally.
The statutory patent term expired in 2021 based on the February 28, 2000 priority date.
Historical generic risk centered on Paragraph IV challenges, section viii carve-outs, and induced-infringement theories.
Bayer’s ownership derived from the acquisition of Schering AG.
Any current freedom-to-operate review must focus on other patents, FDA labeling, formulation rights, and regulatory requirements.

Frequently Asked Questions

Does US 6,987,101 cover drospirenone-only contraception?

No. The claims require treatment of PMDD. Drospirenone-only contraception without PMDD treatment does not fall within the central claim language.

Does the patent cover the Yaz tablet itself?

No. It covers specified methods of using drospirenone, including drospirenone plus ethinylestradiol for PMDD. A separate formulation or composition patent would be required to claim the tablet as a product.

Could a generic omit PMDD from its label?

Historically, a generic applicant could seek a section viii carve-out for PMDD if the relevant regulatory and patent requirements were satisfied. That strategy reduced label-based infringement exposure before the patent expired.

Is the 3 mg drospirenone dose within the patent claims?

Yes. Three milligrams falls within claim 10’s 0.5 mg to less-than-5 mg range and claim 16’s 1.0 mg to 4.0 mg range, assuming the other claim elements are met.

Can US 6,987,101 block a new PMDD product today?

No. The patent’s statutory term expired in 2021. A new product may still face other patents, FDA requirements, product-specific exclusivity, and clinical or regulatory barriers.

References

United States Patent and Trademark Office. (2024). Patent term adjustment and patent term calculation under 35 U.S.C. § 154. https://www.uspto.gov/patents/laws/patent-term-adjustment
United States Patent and Trademark Office. (2006). US Patent No. 6,987,101: Use of drospirenone for treating premenstrual dysphoric disorder. https://patents.google.com/patent/US6987101B2/en
U.S. Food and Drug Administration. (2006). Yaz prescribing information. https://www.accessdata.fda.gov/drugsatfda_docs/label/2006/021676s012lbl.pdf
U.S. Food and Drug Administration. (2024). Approved drug products with therapeutic equivalence evaluations, commonly known as the Orange Book. https://www.fda.gov/drugs/drug-approvals-and-databases/approved-drug-products-therapeutic-equivalence-evaluations-orange-book
U.S. Food and Drug Administration. (2024). Abbreviated new drug application submissions and patent certifications. https://www.fda.gov/drugs/abbreviated-new-drug-application-anda/abbreviated-new-drug-application-anda
Bayer AG. (2006). Bayer completes acquisition of Schering AG. https://www.bayer.com/en/news-stories/bayer-completes-acquisition-of-schering-ag

Foriegn Application Priority Data
Foreign Country	Foreign Patent Number	Foreign Patent Date
Germany	196 54 609	Dec 20, 1996

Country	Patent Number	Estimated Expiration	Supplementary Protection Certificate	SPC Country	SPC Expiration
Australia	5981098	⤷ Start Trial
Germany	19654609	⤷ Start Trial
World Intellectual Property Organization (WIPO)	9827929	⤷ Start Trial
>Country	>Patent Number	>Estimated Expiration	>Supplementary Protection Certificate	>SPC Country	>SPC Expiration

Summary for Patent: 6,987,101