Swiss-Type Claims

Swiss-type claims are a claim format developed in European patent practice to overcome a prohibition on medical method claims: THE UNDERLYING PROBLEM IN EUROPEAN PATENT LAW: Article 53(c) of the European Patent Convention (EPC) prohibits patents on 'methods for treatment of the human or animal body by surgery or therapy'; this prohibition was interpreted to bar claims in the form 'method of treating disease Y using compound X' — the standard method-of-treatment claim used in the US; but what about a NEW THERAPEUTIC USE of a KNOWN compound that is no longer protected by a composition patent?; without some mechanism for use-specific claims, a new indication for a known drug would be unpatentable in Europe even though the discovery is genuinely innovative; THE SWISS-TYPE CLAIM FORMAT — G 05/83 (1985): the EPO Enlarged Board of Appeal (EBoA) created Swiss-type claims as a WORKAROUND to the Art. 53(c) prohibition; FORMAT: 'Use of [compound] for the manufacture of a medicament for the treatment of [disease/condition]'; EXAMPLE: 'Use of sildenafil for the manufacture of a medicament for the treatment of pulmonary arterial hypertension'; WHY IT WORKS: the claim is framed as a METHOD OF MANUFACTURING a medicament (use of X for making Y), NOT as a method of treating patients; manufacturing methods are patentable; the therapeutic USE is built into the purpose of the manufactured medicament; RESULT: a new therapeutic use of a known compound was patentable in Europe via Swiss-type claims even though method-of-treatment claims were barred; SUPERSEDED IN EUROPE (G 02/08, 2010): the EBoA's G 02/08 decision (2010) introduced PURPOSE-LIMITED PRODUCT CLAIMS for second medical uses under EPC Art. 54(5): 'Compound X for use in the treatment of disease Y'; this new format is now the PREFERRED format for second medical use claims in EP applications; Swiss-type claims can no longer be used for applications filed AFTER the G 02/08 decision for new uses where a product claim is possible; HISTORICAL IMPORTANCE: Swiss-type claims are important in the litigation of pharmaceutical patents granted before G 02/08; many existing pharmaceutical patents use Swiss-type claim format and are actively litigated.

The US takes a different approach to second medical use claims, without the prohibition that drove Swiss-type claiming: NO METHODS-OF-TREATMENT PROHIBITION IN US: unlike the EPC, US patent law under 35 U.S.C. § 101 does NOT exclude methods of treatment; method-of-treatment claims are fully patentable subject matter in the US (assuming novelty; non-obviousness; etc.); US METHOD-OF-TREATMENT CLAIMS: the standard US mechanism for second medical uses is the method-of-treatment claim: 'A method of treating [disease] in a patient comprising administering to the patient a therapeutically effective amount of [compound]'; the compound itself need not be newly discovered; the new THERAPEUTIC USE is what is novel and non-obvious; WHAT MAKES A SECOND USE NOVEL AND NON-OBVIOUS: NOVELTY (§ 102): the specific therapeutic use must not have been previously disclosed; 'aspirin for treating fever' is known; 'aspirin for preventing certain cardiovascular events in specific doses' required new clinical discovery; OBVIOUSNESS (§ 103): the new use must not have been obvious to try with a reasonable expectation of success; if the compound was known to treat similar diseases, using it for a related disease may be obvious; TYPES OF SECOND USE CLAIMS IN US: (1) DIFFERENT DISEASE: 'A method of treating [NEW disease] using [known compound]'; (2) DOSAGE REGIMEN: 'A method of treating [disease] comprising administering [known compound] at [specific new dosage schedule]'; if the specific dosage regimen was not previously known; (3) PATIENT POPULATION: 'A method of treating [disease] in [specific sub-population] comprising...'; (4) COMBINATION: 'A method of treating [disease] comprising co-administering [compound A] with [compound B]'; WRITTEN DESCRIPTION FOR SECOND USE CLAIMS: the specification must demonstrate the new use with sufficient evidence; clinical data; in vitro data; or robust preclinical evidence supports the claimed therapeutic use; bare prophetic examples may not be sufficient for biological assertions.

The skinny label strategy is how generic drug manufacturers navigate second medical use patents: BACKGROUND — HATCH-WAXMAN AND GENERIC DRUG APPROVAL: the Hatch-Waxman Act allows generic drug manufacturers to obtain FDA approval using an Abbreviated New Drug Application (ANDA) that relies on the brand manufacturer's safety and efficacy data; the ANDA applicant must certify regarding relevant patents (paragraphs I-IV); A PARAGRAPH III CERTIFICATION: the ANDA applicant certifies the drug has no relevant patents or all relevant patents have expired; A PARAGRAPH IV CERTIFICATION: the ANDA applicant certifies the relevant patent is invalid or not infringed; THE SKINNY LABEL: when a brand drug (e.g., drug A) is approved for two uses (indication 1 and indication 2), and indication 2 is protected by a method-of-treatment patent, the generic manufacturer can seek ANDA approval for indication 1 ONLY; the ANDA label (prescribing information) OMITS indication 2; this is called a 'skinny label' or 'carve-out'; WHY A SKINNY LABEL AVOIDS INFRINGEMENT: the generic does NOT induce infringement of the indication 2 method-of-treatment claim if its label does not promote use of indication 2; induced infringement requires KNOWLEDGE of the patent and SPECIFIC INTENT to induce use of the patented method; a skinny label without indication 2 may negate the specific intent element; GlaxoSmithKline LLC v. Teva Pharmaceuticals USA (Fed. Cir. 2021): the Federal Circuit ruled that a skinny label DID NOT completely insulate the generic from inducement liability when the generic's marketing materials and communications acknowledged that doctors used the drug for the patented indication even though the label lacked it; THE TAKEAWAY: a skinny label reduces but may NOT eliminate second medical use infringement liability if the generic continues to benefit commercially from the patented indication; BRAND STRATEGY: if the second medical use represents significant commercial value, the brand should: ensure the method-of-treatment patent claims cover the indication as practiced by physicians; monitor generic marketing for inducement evidence; file IPRs or litigation aggressively upon generic entry.

Dosage regimen and patient sub-population claims can extend pharmaceutical patent protection significantly: DOSAGE REGIMEN CLAIMS — THE BASICS: a NEW dosage regimen for a KNOWN drug can be patentable as a second medical use: 'A method of treating [disease] comprising administering [compound] to a patient in need thereof at a dose of [X mg] once weekly for [Y weeks]'; WHAT MAKES A DOSAGE REGIMEN PATENTABLE: the specific dosage (amount; frequency; duration) must be NOVEL and NON-OBVIOUS; known doses used for other indications create prior art; the dosage must be clinically meaningful (not just an arbitrary tweak); CLINICAL SUPPORT: robust clinical data or pharmacokinetic/pharmacodynamic (PK/PD) studies showing the dosage regimen's specific efficacy is essential for written description and enablement; AVOIDING OBVIOUSNESS: dosage regimen claims must overcome the presumption that routine dose-optimization experiments (trying different doses to find the best one) are obvious; secondary considerations (unexpected results; commercial success; failure of others to find the optimal dose) are important; PATIENT POPULATION CLAIMS: 'A method of treating [disease] in [patients who are [genetic profile/biomarker positive/negative]] comprising administering [compound]'; PERSONALIZED MEDICINE: biomarker-defined patient populations are increasingly important; if a companion diagnostic identifies which patients respond to a therapy, the narrower patient population claim protects that specific use even if the broader indication is not patentable; EXAMPLE: 'A method of treating non-small cell lung cancer in patients whose tumors have EGFR exon 19 deletions comprising administering gefitinib'; the broader 'NSCLC' claim might be obvious; the specific biomarker-defined use was not; WRITTEN DESCRIPTION FOR PATIENT POPULATION CLAIMS: in vitro or animal data identifying the biomarker correlation is essential; clinical trial data demonstrating the response in the biomarker-positive population is ideal; CLAIM DRAFTING CONSIDERATIONS: draft the broadest defensible independent claim; add dependent claims with narrower dosage ranges; specific patient population subsets; combination therapies; duration of treatment; avoid elements that would be unnecessarily limiting (e.g., do not specify a specific salt form of the compound unless necessary).

Second medical use patents face unique enforcement and validity challenges: ENFORCEMENT CHALLENGES — DIRECT vs. INDUCED INFRINGEMENT: a physician who prescribes a drug in the patented method directly infringes; typically patent owners do NOT sue physicians (impractical; policy reasons; § 271(e)(1) safe harbor for clinical research); the main targets are GENERIC DRUG MANUFACTURERS and PHARMACY BENEFIT MANAGERS (PBMs) who direct use of the drug for the patented indication; INDUCED INFRINGEMENT (§ 271(b)): generic manufacturers who sell drugs labeled for the patented indication INDUCE infringement by physicians who prescribe for that indication; Global-Tech v. SEB (S.Ct. 2011): willful blindness satisfies the knowledge requirement for inducement; Commil v. Cisco (S.Ct. 2015): good faith belief in non-infringement CAN negate inducement; a good faith belief that a specific patient population does not practice the method is relevant; HATCH-WAXMAN LITIGATION PROCESS: upon filing a paragraph IV ANDA, brand manufacturer receives notice and has 45 days to file suit; filing suit triggers an automatic 30-month stay of ANDA approval; during the stay, the parties litigate validity and infringement; VALIDITY CHALLENGES: most common invalidity attacks on second use claims: OBVIOUSNESS (§ 103): prior art showing the compound was known for similar indications; clinical studies suggesting the new indication; KSR flexible standard can make second uses obvious if related indications were known; WRITTEN DESCRIPTION (§ 112): insufficient clinical data to support the specific claimed use; predictive claims without adequate supporting data; ENABLEMENT: for extremely broad patient population claims; Amgen v. Sanofi (S.Ct. 2023) principles apply; OBVIOUSNESS-TYPE DOUBLE PATENTING: if method-of-treatment continuation claims are obvious over composition claims, terminal disclaimer required; IPR LIMITATIONS: IPR proceedings (§ 311) are limited to prior art (§ 102/103) challenges; a method-of-treatment patent that is anticipated or obvious over prior art clinical studies is an IPR target; however, § 112 (written description; enablement) invalidity is a district court defense only; PGR: if filed within 9 months of grant, PGR allows § 101; § 112 challenges — more useful for second use patents with questionable written description.