United States Drug Patent 7,547,719: Eltrombopag Olamine Claims, Scope, Expiration and Patent Landscape
U.S. Patent No. 7,547,719 protects eltrombopag olamine, the bis-monoethanolamine salt of eltrombopag, together with pharmaceutical compositions, thrombocytopenia treatment methods, TPO-receptor agonist uses, combination therapies, and a salt-preparation process. The patent was assigned to Novartis AG and is associated with Promacta in the United States. Its reported patent-term expiration is June 22, 2027, subject to the controlling USPTO and FDA records.[1-3]
The strongest claim is claim 1, which covers the specific salt molecule. Claims 2 through 20 create formulation, therapeutic-use, administration-route, disease-condition, and combination-therapy positions. Claim 21 covers a particular process for making the bis-monoethanolamine salt.
What drug does U.S. Patent 7,547,719 protect?
U.S. Patent 7,547,719 protects eltrombopag olamine, also known as eltrombopag bis-monoethanolamine. Eltrombopag is a nonpeptide thrombopoietin-receptor agonist that stimulates megakaryocyte proliferation and platelet production.[1,4]
| Item |
Detail |
| Patent |
U.S. Patent No. 7,547,719 |
| Patent holder/assignee |
Novartis AG |
| Active ingredient |
Eltrombopag |
| Protected form |
Bis-monoethanolamine salt of eltrombopag |
| Product |
Promacta in the United States; Revolade in many other markets |
| Pharmacologic class |
Thrombopoietin receptor agonist |
| Primary therapeutic area |
Thrombocytopenia |
| Key regulatory pathway |
NDA approval under the Federal Food, Drug, and Cosmetic Act |
| Reported U.S. patent expiration |
June 22, 2027 |
| Patent type |
Small-molecule composition, formulation, method-of-use and manufacturing-process patent |
The claim language uses a systematic chemical name rather than the generic name eltrombopag. The claimed molecule is defined by:
- A biphenyl carboxylic-acid core.
- A hydroxy substituent.
- A hydrazino linkage.
- A substituted pyrazolone ring.
- A 3,4-dimethylphenyl group.
- The Z configuration of the hydrazone linkage.
- Two monoethanolamine equivalents forming the salt.
These structural limitations matter. A compound that lacks the specified Z configuration, changes the substitution pattern, uses a different counterion, or is chemically distinct from the claimed bis-monoethanolamine salt may fall outside claim 1, although other patents or statutory provisions could remain relevant.
What are the claims of U.S. Patent 7,547,719?
The patent has 21 claims organized around six protection categories.
| Claim group |
Claims |
Primary subject matter |
| Compound |
1 |
Eltrombopag bis-monoethanolamine salt |
| Pharmaceutical composition |
2, 10, 11 |
Salt plus carrier, diluent and selected additional agents |
| Treatment methods |
3-6, 8-9, 12-20 |
Thrombocytopenia, TPO-receptor agonism, routes, causes and combination therapy |
| Pharmaceutical-composition process |
7 |
Associating the compound with a carrier or diluent |
| Salt-manufacturing process |
21 |
Preparing the salt from eltrombopag free acid and ethanolamine |
| Combination therapy |
8-11 |
Use with hematopoietic growth factors, cytokines, interleukins and related agents |
Claim 1: composition-of-matter protection
Claim 1 is the central claim. It covers the specifically named bis-monoethanolamine salt, not eltrombopag generally and not every salt of eltrombopag.
A potentially infringing product would normally need to contain the claimed salt in the claimed chemical form. Relevant analytical issues would include:
- Identity of the active pharmaceutical ingredient.
- Counterion identity.
- Stoichiometry of the salt.
- Stereochemical or geometric configuration.
- Solid-state form and hydration state.
- Whether the marketed product contains the claimed salt or a different eltrombopag form.
Because claim 1 is a compound claim, it is generally stronger than a disease-specific method claim against a manufacturer that makes or sells the protected compound. It can reach the active pharmaceutical ingredient before the drug is incorporated into a finished dosage form.
Claim 2: pharmaceutical composition
Claim 2 covers a pharmaceutical composition containing the claimed salt and a pharmaceutically acceptable carrier or diluent.
The claim is broad at the excipient level. It does not require a particular tablet, coating, dissolution profile, particle size, excipient, dosage strength or manufacturing technique. A tablet, capsule, powder, suspension or other dosage form could potentially satisfy the claim if it contains the claimed compound and an acceptable carrier or diluent.
The claim does not, on its face, provide the same detailed formulation specificity found in a formulation patent directed to a defined excipient system or solid-state form. Its value is therefore closely tied to claim 1.
Claims 3 through 6: treatment and TPO-receptor agonism
Claim 3 covers administering a therapeutically effective amount of the compound to treat thrombocytopenia in a human.
Claims 4 and 5 narrow claim 3 by specifying:
- Oral administration.
- Parenteral administration.
Claim 6 covers administering the compound to agonize the TPO receptor in a human.
These claims create method-of-use protection, but their practical enforcement against a generic product depends on how the generic is labeled, marketed and used. A product label that expressly carries a patented indication can create a more direct method-of-use risk. A generic manufacturer may seek a section viii labeling carve-out for a patented indication under the Hatch-Waxman framework, where legally available.[5]
Claims 8 through 11: combination therapy
Claims 8 and 9 cover treatment of thrombocytopenia with the claimed compound together with a second agent. The listed agents include:
- G-CSF.
- GM-CSF.
- TPO.
- M-CSF.
- EPO.
- IL-11.
- Stem cell factor.
- FLT3 ligand.
- LIF.
- IL-3.
- IL-6.
- IL-1.
- IL-5.
- Related biologically active derivatives.
- Other agents acting through comparable mechanisms.
Claims 10 and 11 address compositions containing the compound and additional therapeutic agents. The drafting of these claims contains grammatical and transcription irregularities, including the use of "co-administering" in a composition claim. Claim interpretation would depend on the issued patent text, prosecution history and any judicial construction.
Combination claims are narrower than claim 1 because they require an additional agent or combination context. They may nevertheless remain relevant where a branded label, clinical protocol or generic label encourages concurrent use with hematopoietic agents.
Claims 12 through 20: specified causes of thrombocytopenia
These claims narrow the thrombocytopenia treatment method to defined clinical settings:
| Claims |
Covered condition or cause |
| 12 |
Chemotherapy- or radiation-induced myelosuppression |
| 13-14 |
Organ, bone marrow, stem-cell or liver transplant |
| 15 |
Idiopathic thrombocytopenic purpura |
| 16 |
Myelodysplastic syndromes, aplastic anemia or leukemia |
| 17 |
Viral, fungal, microbial or parasitic infection |
| 18 |
Liver dysfunction |
| 19 |
Surgical procedures |
| 20 |
Antiviral or antibiotic treatment |
These claims are method-of-use claims rather than composition claims. Their commercial importance depends on whether the claimed use is approved, listed in the Orange Book, included in product labeling, or actively promoted.
What process does claim 21 protect?
Claim 21 covers preparation of the bis-monoethanolamine salt by:
- Dissolving eltrombopag free acid in an appropriate organic solvent.
- Adding at least two equivalents of ethanolamine.
- Isolating the prepared compound.
Claim 21 is narrower than claim 1. It requires the specified starting material, solvent-mediated solution step, ethanolamine addition and isolation sequence. A manufacturer could avoid literal infringement if it uses a materially different salt-formation route, although equivalence, process evidence and product-by-process considerations could affect the analysis.
The claim is commercially relevant because it may create manufacturing risk even where a company has developed a different formulation or seeks to use a different production process. It is less powerful than claim 1 if the accused product contains the protected salt but is made by an unrelated process.
When does U.S. Patent 7,547,719 lose exclusivity?
The reported expiration date for U.S. Patent 7,547,719 is June 22, 2027.[2,3] The controlling date is the patent term shown in USPTO records and reflected in the FDA Orange Book, including any patent-term adjustment or other statutory calculation.
The exclusivity timeline for Promacta includes separate FDA regulatory exclusivities:
| Milestone |
Date or period |
| Promacta initial U.S. approval for chronic ITP |
November 2008 |
| New chemical entity exclusivity |
Expired after the initial five-year period |
| Orphan-drug exclusivity for initial ITP indication |
Expired after the applicable seven-year period |
| Additional approved uses |
Added over subsequent FDA supplements |
| Reported expiration of U.S. 7,547,719 |
June 22, 2027 |
FDA exclusivity and patent exclusivity are separate. Expiration of orphan-drug or new-chemical-entity exclusivity does not eliminate a blocking patent. Conversely, expiration of the patent does not necessarily eliminate every regulatory barrier or other patent in the product’s broader estate.
What is the Orange Book status of eltrombopag and Patent 7,547,719?
The FDA Orange Book is the principal source for patents submitted for approved drug products and associated use codes.[3] Patent 7,547,719 has been associated with the Promacta patent estate and is relevant to generic eltrombopag olamine applicants.
Orange Book relevance depends on:
- Whether the patent is currently listed.
- The specific NDA and dosage forms to which it is linked.
- The use code assigned to method claims.
- Whether FDA has accepted, corrected or delisted the submission.
- The applicant’s certification or labeling strategy.
A compound patent can generate a Paragraph IV challenge directed to validity, enforceability or infringement. A method patent can generate a Paragraph IV challenge, a section viii carve-out, or both, depending on the listed use and the proposed generic labeling.[5]
Which companies are challenging the Promacta patent estate?
A complete current list of Paragraph IV filers and related litigation requires the live FDA Orange Book, ANDA litigation dockets and court records. The supplied claim set identifies the protected subject matter but does not establish which companies have filed challenges, which claims were asserted, or whether any settlement has been reached.
The principal generic risk would come from applicants pursuing:
- Eltrombopag olamine tablets.
- Alternative strengths matching Promacta.
- Generic labeling that includes thrombocytopenia indications.
- A section viii carve-out for patented uses.
- A Paragraph IV certification against listed patents.
The most material challenge to this patent would target claim 1 because invalidating or avoiding the salt claim could remove the principal composition barrier. Method claims create narrower, indication-specific litigation exposure.
What patent litigation and settlements affect U.S. Patent 7,547,719?
The claim text alone does not establish litigation outcome, claim validity, settlement terms, launch rights or an authorized-generic arrangement. Those facts must be determined from PACER, district-court opinions, Federal Circuit decisions, FDA records and public settlement documents.
The litigation issues most likely to determine risk are:
| Issue |
Relevance |
| Anticipation |
Whether the exact bis-monoethanolamine salt was disclosed previously |
| Obviousness |
Whether forming the claimed salt would have been predictable from eltrombopag free acid and known salt-selection practices |
| Written description |
Whether the patent adequately supports the exact salt and uses |
| Enablement |
Whether the disclosure enables the full scope of the claims |
| Infringement |
Whether the proposed generic contains the claimed salt |
| Inducement |
Whether labeling or promotion encourages patented uses |
| Process infringement |
Whether the manufacturing route follows claim 21 |
| Enforceability |
Whether prosecution conduct or other equitable issues affect the patent |
The compound claim is usually the primary litigation target. Claims 3 through 20 may remain relevant after a generic obtains approval through a label carve-out or where the generic product is used for a patented indication.
How strong is the patent estate for eltrombopag?
The patent estate has a strong core if claim 1 remains valid and enforceable through its reported 2027 expiration. Claim 1 covers the active salt used in the commercial product and therefore can create a direct product-level barrier.
| Protection type |
Relative strength |
Commercial effect |
| Exact bis-monoethanolamine salt |
High |
Directly targets the marketed active form |
| Broad carrier/diluent composition |
Medium |
Tracks ordinary dosage forms but depends on the salt claim |
| Oral and parenteral treatment |
Medium |
Creates use coverage with possible label carve-outs |
| TPO-receptor agonism |
Medium |
Functional-use coverage, subject to proof and claim construction |
| Disease-specific methods |
Low to medium |
Narrower but relevant to labeled indications |
| Combination therapy |
Low to medium |
Applies only to defined combination use |
| Salt-preparation process |
Medium |
Relevant if the accused manufacturer uses the claimed route |
The estate is more defensible against a conventional generic that uses the same active salt than against a developer using a different active form, a different counterion or a non-infringing manufacturing process.
What generic entry risks exist for Promacta?
The principal generic launch scenarios are:
Launch after patent expiry
A generic applicant may seek approval with a launch date after the reported June 22, 2027 expiration of Patent 7,547,719, assuming no other blocking patents or regulatory exclusivities apply.
Paragraph IV challenge
An applicant may certify that the patent is invalid, unenforceable or not infringed. Filing a Paragraph IV certification can trigger litigation under 35 U.S.C. § 271(e)(2). A timely suit by the patent holder can produce a statutory stay of FDA approval, subject to the Hatch-Waxman rules.[5]
Section viii labeling carve-out
A generic applicant may omit a patented indication from its labeling if the remaining labeling complies with the statutory requirements. This strategy is more relevant to claims 3 through 20 than to claim 1.
Salt or formulation design-around
A company may attempt to use a different eltrombopag salt, polymorph, hydrate or formulation. That strategy must be tested against claim 1, other Orange Book-listed patents and non-listed manufacturing or formulation patents.
Does biosimilar risk apply to eltrombopag?
No. Eltrombopag is a chemically synthesized small molecule, not a biologic subject to the biosimilar pathway under the Public Health Service Act. Competitive entry would generally proceed through an abbreviated new drug application for a generic drug, not a biosimilar application.[6]
The relevant competitors are generic-drug manufacturers, not biosimilar developers. Bioequivalence, pharmaceutical equivalence, labeling, patent certification and possible Paragraph IV litigation are the central regulatory issues.
How does Patent 7,547,719 compare with formulation and method patents?
Patent 7,547,719 is broader at the product level than a typical formulation or method patent because claim 1 covers the active salt itself. A formulation patent may protect a specific tablet composition, particle-size distribution, coating, dissolution profile or solid-state form. A method patent may protect only treatment of a defined condition.
The hierarchy is:
- Claim 1: highest leverage because it covers the active salt.
- Claim 2: composition coverage tied to the active salt.
- Claims 3-6: general treatment and TPO-receptor uses.
- Claims 12-20: narrower clinical indications.
- Claims 8-11: combination products and combination use.
- Claim 21: defined manufacturing route.
A generic that uses the same eltrombopag olamine active ingredient faces the greatest risk under claim 1. A generic that avoids the salt claim may still encounter separate formulation, polymorph, use or manufacturing patents in the broader Novartis estate.
What is the geographic coverage of U.S. Patent 7,547,719?
The patent grants rights only in the United States. Parallel patent families may exist in Europe, Canada, Japan, Australia and other jurisdictions, but their claim scope, validity, term and litigation status must be analyzed separately.
U.S. Patent 7,547,719 does not by itself block manufacture or sale outside the United States. International exposure depends on corresponding national patents, supplementary protection certificates, local regulatory exclusivity and local settlement arrangements.
Key Takeaways
- U.S. Patent 7,547,719 is primarily a salt patent covering eltrombopag bis-monoethanolamine, the active form associated with Promacta.
- Claim 1 is the most commercially important claim because it provides product-level protection.
- Claims 2 through 20 cover compositions, TPO-receptor agonism, thrombocytopenia treatment, administration routes, specific causes of thrombocytopenia and combination therapy.
- Claim 21 protects a specific process using eltrombopag free acid, ethanolamine and an organic solvent.
- The reported U.S. patent expiration date is June 22, 2027.
- Eltrombopag is a small molecule, so generic ANDA competition applies rather than biosimilar competition.
- Paragraph IV litigation would likely focus first on claim 1, while section viii carve-outs are more relevant to method-of-use claims.
- A different eltrombopag salt or manufacturing process may reduce exposure to this patent but does not automatically eliminate risk from the broader patent estate.
- FDA Orange Book listings, use codes, ANDA certifications and court records control the current litigation and launch analysis.
Frequently Asked Questions
Is eltrombopag olamine the same as eltrombopag?
Eltrombopag is the active pharmaceutical moiety. Eltrombopag olamine is the bis-monoethanolamine salt specifically protected by claim 1 of U.S. Patent 7,547,719.
Can a generic manufacturer avoid Patent 7,547,719 by using eltrombopag free acid?
Possibly, but the product would need to avoid claim 1 and any other applicable patents. A free-acid product may also face pharmaceutical-equivalence, bioequivalence, stability and regulatory issues.
Does Patent 7,547,719 cover every treatment of thrombocytopenia?
No. The treatment claims require administration of the specifically claimed compound. Claims 12 through 20 further narrow the method to listed causes or clinical settings.
Does the patent cover Promacta’s tablet excipients?
Claim 2 broadly covers a composition containing the salt and a pharmaceutically acceptable carrier or diluent. It does not specifically claim every Promacta excipient combination or every tablet manufacturing parameter.
What evidence is most important in a Patent 7,547,719 infringement analysis?
The most important evidence is the generic product’s active chemical form, salt stoichiometry, solid-state characterization, proposed labeling, ANDA patent certifications and manufacturing process. These facts determine whether claim 1, the method claims or claim 21 presents the principal risk.
References
- U.S. Patent No. 7,547,719, “Bis-(monoethanolamine) salt of eltrombopag.” U.S. Patent and Trademark Office.
- U.S. Patent and Trademark Office. (n.d.). Patent term adjustment and patent term information for U.S. Patent No. 7,547,719.
- U.S. Food and Drug Administration. (n.d.). Approved drug products with therapeutic equivalence evaluations, Orange Book.
- U.S. Food and Drug Administration. (2023). Promacta prescribing information. Novartis Pharmaceuticals Corporation.
- Drug Price Competition and Patent Term Restoration Act of 1984, 21 U.S.C. § 355(j); 35 U.S.C. § 271(e)(2).
- Public Health Service Act, 42 U.S.C. § 262.
