US Drug Patent RE39050: Scope, Claims, Expiration, and Raloxifene Patent Landscape

US Reissue Patent RE39050 protected the use of raloxifene hydrochloride for preventing and treating post-menopausal osteoporosis, particularly at a 60 mg daily dose. The patent was assigned to Eli Lilly and Company and was tied to Evista, the company’s raloxifene product. Its enforceable term expired in March 2014, eliminating the patent as a current barrier to generic raloxifene hydrochloride entry.

What drug does US RE39050 cover?

The compound of Formula I in RE39050 is raloxifene, administered primarily as raloxifene hydrochloride.

Raloxifene is a selective estrogen receptor modulator, or SERM. The approved product is raloxifene hydrochloride, marketed in 60 mg tablets under the Evista brand.

Attribute	Detail
Active ingredient	Raloxifene hydrochloride
Drug class	Selective estrogen receptor modulator
Brand	Evista
Original sponsor	Eli Lilly and Company
FDA indication	Prevention and treatment of post-menopausal osteoporosis; reduction of invasive breast-cancer risk in specified populations
Covered dose in RE39050	Primarily 60 mg once daily
Dosage form relevant to commercial product	Oral tablet
Patent type	Reissue patent
Current status	Expired

Raloxifene hydrochloride is chemically distinct from bazedoxifene acetate, the SERM used in Duavee. RE39050 does not cover bazedoxifene, conjugated estrogens, or the Duavee combination.

What is the prosecution and priority history of RE39050?

RE39050 is a reissue of an earlier Eli Lilly patent covering raloxifene-related inventions and osteoporosis treatment methods. The relevant patent family traces back to a March 17, 1989 priority date associated with the raloxifene patent estate.

Event	Date
Earliest relevant priority	March 17, 1989
Original patent	US 5,393,763
Reissue patent	US RE39,050
RE39050 issue date	August 26, 2003
Patent expiration	March 17, 2014
FDA product associated with the patent estate	Evista, NDA 020815

The reissue designation is legally significant. A reissue patent is issued to correct an error in an earlier patent. It does not automatically create a new full patent term. The reissue remains subject to the expiration date of the original patent term, including any applicable terminal disclaimer or statutory adjustment.

What does claim 1 of RE39050 cover?

Claim 1 is a method-of-treatment claim directed to administration of raloxifene for preventing or treating post-menopausal osteoporosis.

Its principal elements are:

The patient is a human.
The patient is a woman in need of treatment to prevent or treat post-menopausal osteoporosis.
The treatment objective is inhibition of post-menopausal bone loss or bone resorption.
The administered compound is Formula I, or a pharmaceutically acceptable salt or solvate.
The compound is administered within a specified daily-dose range.

The supplied version of claim 1 contains apparent OCR or transcription corruption:

"about 50 to about 150 55 to 65 mg/day"

The same issue appears in dependent claims 8 and 9, where the text combines alternative dose values:

"75 55 mg/day"
"100 65 mg/day"

The commercially and clinically relevant narrowed dose is 60 mg/day. The cleanest operative interpretation of the supplied claims is that the patent claims a daily dose range centered on approximately 60 mg, with dependent claims specifying 60 mg and other listed dose amounts.

The exact issued claim text controls infringement analysis. The corrupted ranges should not be treated as authoritative without comparison against the certified patent document and reissue file history.

What are the limitations of claim 1?

Patient limitation

Claim 1 requires a human woman in need of treatment for post-menopausal osteoporosis. The patient need not necessarily have a confirmed diagnosis under claim 1, because claim 2 adds diagnosed post-menopausal osteoporosis as a further limitation.

The claim therefore reaches both:

Treatment of diagnosed post-menopausal osteoporosis; and
Preventive treatment where the patient is considered at risk or otherwise in need of treatment.

Therapeutic-purpose limitation

The claim is limited to preventing or treating post-menopausal osteoporosis and to inhibiting bone loss or bone resorption associated with that condition.

Administration of raloxifene for an unrelated purpose, such as reducing breast-cancer risk, would not by itself satisfy this limitation.

Compound limitation

The compound must be Formula I, a pharmaceutically acceptable salt, or a solvate. Claim 12 specifically narrows this to the hydrochloride salt.

For commercial Evista use, the relevant embodiment is raloxifene hydrochloride.

Dose limitation

The claims focus on daily oral dosing in the approximate 60 mg range. Claim 7 expressly recites 60 mg/day. Claims 13, 14, and 15 also focus on raloxifene hydrochloride at 60 mg/day.

A product or treatment using a substantially different dose could present a non-infringement position, although the outcome would depend on the precise claim language, prosecution history, equivalency arguments, and actual use instructions.

How do claims 2 through 11 expand or narrow claim 1?

Claim	Subject matter	Scope effect
1	Formula I for preventing or treating post-menopausal osteoporosis at a stated dose range	Independent method claim
2	Patient diagnosed with post-menopausal osteoporosis	Narrows claim 1
3	Human is a post-menopausal female	Clarifies and narrows the patient class
4	Human is a male	Creates an unusual dependent limitation that may conflict with the post-menopausal-woman language in claim 1
5	Prophylactic administration	Covers prevention rather than only treatment
6	Administration at approximately 60 to 150 mg/day	Dose-range limitation
7	Administration at 60 mg/day	Key commercial-dose claim
8	Administration at a listed dose value, but supplied text is corrupted	Requires certified claim text
9	Administration at a listed dose value, but supplied text is corrupted	Requires certified claim text
10	Administration at 125 mg/day	Specific dose claim
11	Administration at 150 mg/day	Specific dose claim

Claim 4 is structurally problematic as presented. Claim 1 identifies a "post-menopausal woman," while claim 4 states that the human is a male. A male cannot ordinarily be post-menopausal in the conventional medical sense. The claim may reflect an amendment, transcription error, or broader underlying language in the issued patent. Its scope should be assessed from the official issued text rather than the supplied transcription.

What do claims 12 through 15 protect?

Claims 12 through 15 are the most commercially relevant claims because they combine raloxifene hydrochloride with the 60 mg/day dose and the osteoporosis indication.

Claim 12

Claim 12 narrows the compound to the hydrochloride salt of Formula I.

For raloxifene, this corresponds to raloxifene hydrochloride.

Claim 13

Claim 13 covers administration of raloxifene hydrochloride at 60 mg/day.

This claim most closely tracks the approved Evista regimen.

Claim 14

Claim 14 covers prevention of post-menopausal osteoporosis using raloxifene hydrochloride at 60 mg/day.

It is a prophylactic method-of-use claim.

Claim 15

Claim 15 covers treatment of post-menopausal osteoporosis using raloxifene hydrochloride at 60 mg/day.

It is a treatment method-of-use claim directed to diagnosed or clinically treated osteoporosis.

Claims 14 and 15 divide the principal commercial indication into prevention and treatment. A generic label carrying both indications could have raised method-of-use patent issues while the patent remained unexpired.

When did RE39050 lose exclusivity?

RE39050 expired on March 17, 2014. The patent therefore does not create a current US exclusivity barrier to generic raloxifene hydrochloride.

The expiration date also applies to the related original patent term. The reissue did not reset the patent term.

Exclusivity category	Status
RE39050 patent term	Expired March 17, 2014
Original raloxifene composition patent	Expired
Method-of-use protection in RE39050	Expired
Current patent-based generic blocking power	None from RE39050
Historical Paragraph IV relevance	High before 2014
Current Paragraph IV relevance	None for an expired patent

FDA regulatory exclusivity and patent exclusivity are separate. Any FDA new-drug exclusivity for Evista ended before the patent expiration date and does not revive the expired patent.

What was the Orange Book status of RE39050?

RE39050 was associated with the Evista NDA and was listed in the FDA Orange Book as a patent covering an approved method of using raloxifene hydrochloride. The related original patent, US 5,393,763, formed part of the same core patent estate.

The relevant Orange Book concepts were:

Raloxifene hydrochloride as the active ingredient.
Evista as the reference-listed drug.
Osteoporosis prevention and treatment as the covered use.
Method-of-use patent protection rather than a current composition-of-matter barrier.

Once the listed patent expired, an ANDA applicant no longer needed to defeat the patent through a successful Paragraph IV litigation strategy. FDA approval could proceed subject to the remaining requirements of the ANDA pathway, including bioequivalence and any applicable labeling provisions.

Which companies challenged the raloxifene patent estate?

Generic companies challenged or prepared to challenge the Evista patent estate as the 2014 expiration date approached. Publicly reported market participants included major generic manufacturers and their subsidiaries, such as Teva, Watson/Actavis, Barr, and Apotex, depending on the specific ANDA and litigation proceeding.

The principal legal theories available to challengers were:

Invalidity based on anticipation.
Obviousness based on prior art concerning SERMs, raloxifene, and osteoporosis.
Lack of written description or enablement.
Non-infringement based on proposed labeling or dosing.
Lack of enforceability, including reissue-related and prosecution-history defenses.

The practical significance of those challenges declined once RE39050 and the related core patents expired in 2014.

What Paragraph IV risks did RE39050 create?

Before expiration, a generic applicant seeking approval for a raloxifene hydrochloride product could have filed a Paragraph IV certification asserting that RE39050 was invalid, unenforceable, or would not be infringed.

A Paragraph IV notice would have created potential Hatch-Waxman litigation. If the patent owner sued within the statutory period, FDA approval could have been delayed by the statutory stay, subject to the applicable statutory maximum and litigation outcome.

The principal infringement risk would have focused on the generic label:

Does the label include prevention of post-menopausal osteoporosis?
Does it include treatment of post-menopausal osteoporosis?
Does it direct use at 60 mg/day?
Does it identify raloxifene hydrochloride?
Does the label encourage physicians to administer the drug in the patented manner?

Because method-of-use claims can be infringed through induced infringement, a generic applicant could face risk even without manufacturing a different chemical entity. Label design, carve-outs, prescribing information, and actual commercial promotion were central to the analysis.

How strong was the patent estate for Evista?

The Evista estate was commercially strong during the protected period because the patents covered both the raloxifene molecule and the principal osteoporosis use.

Patent category	Representative patent	Commercial function	Current status
Core compound and raloxifene technology	US 5,393,763	Protected raloxifene-related invention	Expired
Osteoporosis method of use	RE39050	Covered prevention and treatment of post-menopausal osteoporosis	Expired
Dose-specific use	RE39050 claims 7 and 13-15	Focused on 60 mg/day raloxifene hydrochloride	Expired
Product labeling	Evista NDA 020815	Defined approved use and dosing	No patent exclusivity remaining

The estate had a strong historical blocking position because it combined composition and use protection. Its present strength is zero as an enforceable patent barrier because the relevant patents have expired.

What formulations are protected by RE39050?

RE39050 is primarily a method-of-use patent, not a broad formulation patent.

The claims do not principally require:

A particular tablet excipient;
A specific dissolution profile;
A controlled-release matrix;
A particular coating;
A defined particle-size distribution; or
A specialized manufacturing process.

The claims require administration of Formula I or its pharmaceutically acceptable salt or solvate. A conventional immediate-release raloxifene hydrochloride tablet administered at 60 mg/day would fall within the central commercial embodiment.

A different formulation could still infringe if it delivers raloxifene hydrochloride in the claimed manner for the claimed osteoporosis purpose and at the claimed dose. Conversely, formulation differences alone would not necessarily avoid infringement while the patent was active.

Did RE39050 protect manufacturing methods?

No. The supplied claims do not claim the synthesis, crystallization, purification, tableting, packaging, or manufacturing process for raloxifene hydrochloride.

A manufacturing patent could create a separate barrier if it claimed:

A particular raloxifene intermediate;
A stereochemical or polymorphic form;
A salt-preparation process;
A high-purity raloxifene hydrochloride process; or
A specific pharmaceutical composition.

Those rights would need to be analyzed separately from RE39050. RE39050 itself is directed to medical use.

What litigation and settlement issues mattered?

The principal commercial litigation risk was generic entry before the March 2014 expiration date. Litigation involving the Evista estate would have centered on:

Validity of the raloxifene compound and use claims;
Scope of the reissued claims;
Whether the generic label induced use for osteoporosis;
Whether prevention and treatment indications could be carved out;
Whether a generic launch could proceed under a skinny label; and
Whether a settlement delayed entry beyond the patent expiration date.

Any settlement agreement would require review of the individual district-court docket, ANDA number, settlement terms, and Federal Trade Commission treatment. A generic launch after March 17, 2014 does not, by itself, establish that a settlement authorized entry. Expiration independently removed the patent bar.

How does RE39050 compare with competing osteoporosis drugs?

Drug	Active ingredient	Main class	Typical historic patent issue	Current competitive position
Evista	Raloxifene hydrochloride	SERM	US 5,393,763 and RE39050	Generic competition established
Fosamax	Alendronate sodium	Bisphosphonate	Composition, dosing, and method patents	Generic
Actonel	Risedronate sodium	Bisphosphonate	Composition and method patents	Generic
Boniva	Ibandronate sodium	Bisphosphonate	Composition and dosing patents	Generic
Prolia	Denosumab	Biologic RANKL inhibitor	Biologic and formulation patent estate	Biosimilar and interchangeability risks depend on current patents and FDA status
Evenity	Romosozumab-aqqg	Sclerostin inhibitor	Biologic, formulation, and use patents	Later-stage biologic exclusivity
Duavee	Conjugated estrogens/bazedoxifene	Estrogen/SERM combination	Combination and formulation protection	Separate estate from raloxifene

RE39050 did not create biologic exclusivity and does not affect denosumab or romosozumab biosimilar entry. Its competitive relevance was limited to raloxifene-containing products and equivalent osteoporosis-use labeling.

What generic launch risks exist today?

For US commercial planning, RE39050 presents no current launch risk. A generic raloxifene hydrochloride applicant’s principal issues are now regulatory and commercial rather than patent-based:

ANDA approval;
Bioequivalence to the reference product;
Appropriate labeling;
Supply reliability;
Reimbursement and formulary access;
Brand retention or authorized-generic strategy;
Product liability and pharmacovigilance;
Any separate, unexpired patent not captured by RE39050.

The main historical launch window opened after March 17, 2014. Generic raloxifene products subsequently entered the US market, confirming that the expired Evista patent estate no longer prevented competition.

What is the current commercial and revenue exposure?

The patent’s revenue exposure was highest before expiration because Evista was the branded product associated with the patented 60 mg osteoporosis regimen. After expiration, revenue exposure shifted from patent protection to generic substitution and price erosion.

Period	Patent effect	Commercial implication
Before 2014	Composition and method patents protected the product	Brand control and delayed generic entry
2014 expiration period	Core patent barriers ended	Generic entry became legally viable
After 2014	No RE39050 exclusivity	Price competition and market-share erosion
Current period	Patent does not block generic raloxifene	Value depends on brand, distribution, and prescribing economics

Key Takeaways

RE39050 covers methods of preventing or treating post-menopausal osteoporosis with Formula I, principally raloxifene hydrochloride.
Claims 13 through 15 are the closest match to the commercial Evista regimen: raloxifene hydrochloride at 60 mg/day.
The patent is a method-of-use patent, not a manufacturing or broad formulation patent.
The supplied claim text contains OCR or transcription errors, particularly in the dose ranges and claim 4.
RE39050 expired on March 17, 2014.
The related original raloxifene patent, US 5,393,763, also expired and no longer blocks generic entry.
Historical Paragraph IV risk focused on invalidity, non-infringement, label carve-outs, and induced infringement.
RE39050 does not affect bazedoxifene, Duavee, denosumab, romosozumab, or biosimilar regulation.
Current generic raloxifene risk is regulatory and commercial, not based on RE39050.

FAQs About US RE39050 and Raloxifene

Is RE39050 still enforceable against generic raloxifene?

No. RE39050 expired on March 17, 2014.

Does RE39050 cover raloxifene for breast-cancer risk reduction?

The supplied claims are directed to prevention or treatment of post-menopausal osteoporosis. They do not expressly claim breast-cancer risk reduction.

Does a 60 mg raloxifene hydrochloride tablet fall within RE39050?

Historically, the 60 mg raloxifene hydrochloride osteoporosis regimen was the central commercial embodiment of claims 13 through 15. The patent is now expired.

Does RE39050 cover male osteoporosis treatment?

The supplied claim set includes a dependent claim referring to a male, but that language is inconsistent with claim 1's post-menopausal-woman limitation and appears potentially corrupted. The official issued claim and prosecution history would control.

Is raloxifene a biosimilar product?

No. Raloxifene hydrochloride is a small-molecule drug approved through the NDA/ANDA framework. Generic raloxifene is not a biosimilar.

References

U.S. Food and Drug Administration. (n.d.). Approved drug products with therapeutic equivalence evaluations: Orange Book.
U.S. Food and Drug Administration. (n.d.). Evista (raloxifene hydrochloride) prescribing information.
U.S. Patent and Trademark Office. (2003). United States Patent No. RE39,050: Methods of treatment of osteoporosis.
U.S. Patent and Trademark Office. (1995). United States Patent No. 5,393,763.
U.S. Food and Drug Administration. (n.d.). Electronic Orange Book: NDA 020815, Evista.
U.S. Code, 35 U.S.C. §§ 251, 271, 282.
U.S. Code, 21 U.S.C. § 355.

Country	Patent Number	Estimated Expiration	Supplementary Protection Certificate	SPC Country	SPC Expiration
Australia	1355195	⤷ Start Trial
Australia	702575	⤷ Start Trial
Brazil	9500784	⤷ Start Trial
Canada	2141999	⤷ Start Trial
China	1119530	⤷ Start Trial
Colombia	4340681	⤷ Start Trial
Czech Republic	9500313	⤷ Start Trial
>Country	>Patent Number	>Estimated Expiration	>Supplementary Protection Certificate	>SPC Country	>SPC Expiration

Details for Patent: RE39050

Summary for Patent: RE39050