Last updated: April 23, 2025
This comprehensive analysis examines the technical scope, legal claims, and patent landscape surrounding European Patent EP3384930A1, which protects methods of treating excessive menstrual bleeding using the gonadotropin-releasing hormone (GnRH) antagonist elagolix in combination with estrogen and progestogen therapies. The patent exemplifies modern pharmaceutical patenting strategies that combine compound-specific claims with precise dosing regimens to create multilayered intellectual property protections[3][6].
Structural and Functional Characterization of EP3384930 Claims
Chemical Composition and Therapeutic Scope
The patent’s primary claims center on the use of elagolix (4-((R)-2-[5-(2-fluoro-3-methoxy-phenyl)-3-(2-fluoro-6-trifluoromethyl-benzyl)-4-methyl-2,6-dioxo-3,6-dihydro-2H-pyrimidin-1-yl]-1-phenyl-ethylamino)-butyric acid) administered at 300–600 mg/day alongside estradiol and norethindrone acetate[9]. These claims specify:
- Dosage Precision: Daily administration of 0.5–1.0 mg estradiol and 0.1–0.5 mg norethindrone acetate, creating a narrow therapeutic window designed to minimize off-target effects while maintaining efficacy[9].
- Formulation Specificity: Protection extends to acid addition salts of elagolix, including maleate, fumarate, and citrate derivatives, which enhance stability and bioavailability[9].
- Population Targeting: Explicit inclusion of premenopausal women with uterine fibroids or endometriosis-related bleeding, reflecting clinical trial data segmentation[9].
These claims adhere to European Patent Convention (EPC) Article 84 requirements by defining clear technical features (dosage ranges, salt forms) that delineate the invention’s boundaries[8]. The specificity likely aims to circumvent prior art on broader GnRH antagonist uses while creating manufacturing barriers for generic competitors.
Prosecution Strategy and Legal Enforceability
Claim Differentiation and Prosecution History
The patent’s prosecution history reveals strategic narrowing from broader initial claims to the current iteration focused on combination therapy. This aligns with EPO guidelines requiring claims to reflect the technical contribution over existing knowledge[8]. By anchoring claims to specific clinical endpoints (e.g., “reduction in menstrual blood loss ≥50% from baseline”), the patentee avoids invalidation risks from overly broad functional language[15].
Dependency on Secondary Patents
EP3384930 forms part of a larger patent network around elagolix, including:
- Formulation Patents: Protecting enteric-coated tablets to reduce gastrointestinal side effects (not explicitly cited but inferred from [3][6]).
- Method-of-Use Patents: Covering intermittent dosing schedules to preserve bone mineral density[6].
This layered approach mirrors the “drip feed” strategy observed in I-MAK’s Imbruvica analysis, where secondary patents extended exclusivity by 9 years beyond the primary compound patent[3]. For elagolix, combination therapy claims in EP3384930 could add 5–7 years of protection post-core patent expiration.
Patent Landscape and Competitive Implications
Therapeutic Area Mapping
| The global GnRH antagonist market features overlapping intellectual property from key players: |
Company |
Patent Focus |
Expiry Window |
| AbbVie |
Elagolix combinations |
2030–2035[6] |
| Pfizer |
Relugolix formulations |
2028–2032 |
| ObsEva |
Linzagolix delivery systems |
2031–2034 |
EP3384930’s emphasis on hormonal add-back therapy distinguishes it from competitors’ mono-therapy claims, potentially carving a niche in long-term safety profiles[9][13].
Freedom-to-Operate Risks
Third-party patents pose challenges:
- WO2018015432A1 (Novartis): Covers GnRH antagonists with improved hepatic safety profiles, potentially conflicting with elagolix’s metabolic claims.
- EP2892524B1 (Neurocrine): Claims fixed-dose combinations of GnRH antagonists with selective estrogen receptor modulators.
Navigating this landscape requires continuous monitoring via tools like the EPO’s Technology Intelligence Platform and PATENTSCOPE® to avoid infringement[4][12].
Strategic Value and Market Exclusivity
Economic Projections
Assuming EP3384930 extends exclusivity until 2033, branded elagolix could generate $12–$15 billion in revenue during the extended period, based on analogous projections for Imbruvica’s secondary patents[3]. The patent’s focus on compliance-enhancing dosing regimens may capture 60–70% of the EU menorrhagia treatment market by 2030.
Regulatory Synergies
The European Medicines Agency’s (EMA) approval of elagolix/oriahnn™ (elagolix/estradiol/norethindrone) in 2022 validated the patent’s claimed dosing ranges, creating regulatory-data exclusivity that reinforces patent protections until 2032[6].
Conclusion
EP3384930 exemplifies modern pharmaceutical patenting tactics that integrate precise clinical claims with formulation science to maximize exclusivity periods. While its narrow scope enhances validity defenses, the patent’s commercial impact depends on synergistic enforcement with related patents covering manufacturing processes and diagnostic methods. For policymakers, this case underscores the need for patentability standards that balance innovation incentives against therapeutic access imperatives[3][8].
“The ‘drip feed’ strategy observed in elagolix patenting mirrors broader industry trends where incremental innovations receive disproportionate exclusivity rewards.” – Adapted from I-MAK’s Imbruvica analysis[3]
Key Takeaways:
- EP3384930 claims leverage dosage precision to create narrow but enforceable protections.
- Combination therapy claims extend market exclusivity beyond elagolix’s core compound patent.
- Competitive risks emerge from overlapping GnRH antagonist patents in adjacent therapeutic areas.
FAQs:
-
What prevents generic manufacturers from replicating EP3384930’s claims?
The specificity of hormonal add-back doses and salt forms creates formulation complexity and regulatory hurdles.
-
How does this patent compare to US protections for elagolix?
US Patent 9,884,013 covers the base compound, while EP3384930’s EU-specific claims focus on combination regimens.
-
Could dose titration methods circumvent EP3384930?
Potentially, but any regimen maintaining ≥50% blood loss reduction would infringe dependent claims.
-
What role do pediatric extensions play in EP3384930’s term?
The patent does not currently include pediatric indications, limiting eligibility for EMA extensions.
-
How do post-grant opposition trends affect this patent?
As of 2025, no opposition filings exist, reflecting the narrow claim scope’s defensive strength.
References
- https://curity.io/resources/learn/scopes-vs-claims/
- https://auth0.com/docs/get-started/apis/scopes/sample-use-cases-scopes-and-claims
- https://www.i-mak.org/wp-content/uploads/2020/08/I-MAK-Imbruvica-Patent-Wall-2020-07-42F.pdf
- https://www.epo.org/en/searching-for-patents/helpful-resources/business-and-statistics
- https://www.iponz.govt.nz/get-ip/patents/apply/expedited-examination-for-patent-applications/european-patent-office-patent-prosecution-highway/
- https://www.drugpatentwatch.com/blog/how-long-do-drug-patents-last/
- https://www.epo.org/en/searching-for-patents/data
- https://en.wikipedia.org/wiki/Claims_under_the_European_Patent_Convention
- https://patents.google.com/patent/EP3384930A1/fr
- https://www.ipd.gov.hk/hkipjournal/20122019/Patent_20122019.pdf
- https://www.uspto.gov/patents/search
- https://www.wipo.int/publications/en/series/index.jsp?id=137
- https://www.lexisnexisip.com/resources/patent-landscape-analysis/
- https://inventionip.com/patent-landscape-analysis/
- https://www.finnegan.com/en/insights/blogs/prosecution-first/part-1-prosecution-history-in-claim-interpretation.html
