ANDA Litigation

ANDA litigation is the specialized patent infringement framework created by the Hatch-Waxman Act: HOW ANDA LITIGATION STARTS: a generic drug company files an Abbreviated New Drug Application (ANDA) with the FDA, relying on the branded drug's (NDA holder's) safety and efficacy data; the generic applicant must include certifications for each patent listed in the FDA's Orange Book for the reference drug; PARAGRAPH IV CERTIFICATION: the generic applicant certifies that the listed patent: is invalid; unenforceable; or will not be infringed by the generic's proposed product; filing a Paragraph IV certification automatically constitutes patent infringement under § 271(e)(2) — a legal fiction created to allow litigation before actual commercial launch; NOTICE AND RESPONSE PERIOD: within 20 days of filing, the generic must notify: the NDA holder (brand); AND the patent owner (may be different from NDA holder); BRAND'S 45-DAY WINDOW: the brand has 45 days from notification to file an infringement suit; if the brand does NOT sue within 45 days: FDA approval can proceed after patent expiry; no 30-month stay applies; 30-MONTH AUTOMATIC STAY: if the brand sues within 45 days: FDA cannot approve the ANDA for 30 months (or until the patent litigation is resolved, whichever is earlier); the stay is automatic — no court order needed; if the patent expires or is found invalid/not infringed during the 30 months, the stay terminates; FDA APPROVAL AFTER STAY: if 30 months expire without a court decision, FDA can approve the ANDA; the patent dispute continues in court; at-risk launch becomes possible.

The 180-day exclusivity is a powerful incentive for generics to challenge branded drug patents: FIRST FILER EXCLUSIVITY: the first generic applicant to file an ANDA with a Paragraph IV certification receives 180 days of market exclusivity; during this period: FDA cannot approve other ANDA applicants for the same drug; the first filer has the market to itself (along with the brand); VALUE: for blockbuster drugs, 180 days of semi-exclusive generic sales can be worth hundreds of millions of dollars; WHAT TRIGGERS THE 180-DAY CLOCK: the 180-day period starts from: the earlier of: (a) the date of first commercial marketing of the drug by the first filer; OR (b) a court decision that all patents in question are invalid or not infringed; FORFEITURE OF EXCLUSIVITY: first-filer exclusivity is forfeited if: the first filer fails to market within 75 days of a final court decision/FDA approval; the first filer does not win a court decision within 30 months of FDA acceptance of the ANDA and fails to market; the first filer withdraws or amends its Paragraph IV certification to a Paragraph III; PARA IV LITIGATION SETTLEMENT TIMING: many settlements occur just before the 30-month stay expires; brands often grant the first filer a license to launch on a specific 'launch date' — often after the composition patent expires but before formulation patents; subsequent generics cannot enter during the first filer's 180 days; STACKED EXCLUSIVITIES: a drug may have multiple ANDAs from different generics, each for a different indication or formulation; the 180-day exclusivity for each patent/application is separate; IMPORTANCE IN PRACTICE: the 180-day exclusivity creates a strong incentive for at least one generic to challenge branded drug patents; this 'Paragraph IV lottery' has dramatically increased generic challenges.

ANDA litigation focuses on specific patent challenges that generic companies bring against branded drug patents: INVALIDITY ISSUES: (a) OBVIOUSNESS: most common challenge; the claimed drug compound is structurally obvious over known prior art compounds; lead compound analysis: Takeda Chemical Industries v. Alphapharm (2007): the structural similarity between prior art and claimed compound does not create a presumption of obviousness; secondary considerations (unexpected results) carry real weight in pharmaceutical cases; (b) DOUBLE PATENTING: the same assignee has two patents covering the same invention; obvious-type double patenting (ODP): claiming obvious variants of a compound covered by an earlier patent; terminal disclaimer required to overcome ODP; (c) WRITTEN DESCRIPTION / ENABLEMENT: patent specification does not adequately describe or enable the full scope of the claims; particularly in cases with broad genus claims claiming thousands of compounds without adequate examples; (d) INEQUITABLE CONDUCT: prior art was intentionally withheld from the USPTO; must prove specific intent to deceive; if found, the patent is unenforceable; NON-INFRINGEMENT ISSUES: (a) CLAIM CONSTRUCTION: the branded drug's patent claims should be construed narrowly to exclude the generic's proposed product; (b) FORMULATION DIFFERENCES: the generic's formulation avoids specific claim limitations (excipients; manufacturing process); (c) METHOD CLAIM BYPASS: the generic does not intend to induce infringement of method-of-use claims; label does not promote the patented method; SKINNY LABELING: generic can carve out the patented indication from its FDA label; the generic's label omits the indication covered by the method-of-use patent; GlaxoSmithKline LLC v. Teva Pharmaceuticals (Fed. Cir. 2021): skinny labeling may not fully protect generic if it promotes the patented use; concern is evidence of induced infringement.

Reverse payment settlements are agreements where the brand pays the generic to delay market entry — the subject of major antitrust scrutiny: WHAT IS A REVERSE PAYMENT: in a typical settlement: brand pays MONEY (or equivalent value) to the generic; in exchange: the generic agrees not to enter the market for a specified period; sometimes the brand also grants the generic a license on a specific 'entry date' (before composition patent expiry but after some protection period); WHY BRANDS PAY GENERICS: the branded company has much more to lose from the generic entering (lost exclusivity on a multi-billion dollar product) than the generic has to gain (180-day exclusivity on a subset of the market); brands rationally pay generics to delay entry; generics rationally accept payments because: the litigation could fail; at-risk launch has downside exposure; guaranteed payment is valuable; ANTITRUST ANALYSIS BEFORE FTC v. ACTAVIS: Federal Circuit (pre-2013): held reverse payments were legal as long as the payment was within the scope of the patent's exclusionary right; FTC v. ACTAVIS (S.Ct. 2013): reversed this; 'pay-for-delay' settlements are subject to the RULE OF REASON antitrust analysis under Sherman Act § 1; large unexplained payments from brand to generic are evidence of anticompetitive intent; the settlement IS NOT automatically justified by the scope of the patent; RULE OF REASON ANALYSIS: the plaintiff (FTC or private plaintiff) must prove anticompetitive effect; the defendant must show procompetitive justification; the court weighs the effects; WHAT CONSTITUTES 'PAYMENT': cash is obvious; but non-cash payments also count: brand not launching an authorized generic (AG) during the 180-day exclusivity period — denying competition to the first filer = highly valuable; side deals (e.g., co-promotion agreements, supply agreements at favorable terms); PRACTICE AFTER ACTAVIS: settlements now more carefully structured; brands structure value transfers to minimize 'large, unexplained' payment; the FTC continues to challenge settlements.

ANDA litigation strategy differs dramatically based on whether you are the brand or the generic: BRAND STRATEGY: (a) ORANGE BOOK LISTING: list ALL relevant patents in the Orange Book; failure to list a patent means the generic does not need to certify Paragraph IV for that patent; listed patents get 30-month stay protection; (b) NARROW PATENT DRAFTING vs. BROAD: broad claims get Orange Book protection but are more vulnerable to invalidity; narrow claims may be harder to invalidate but easier to design around; (c) PATENT THICKET: file multiple overlapping patents across different aspects (compound, formulation, method, metabolite); requires multiple Paragraph IV certifications; (d) TRACK ANDA APPLICATIONS: brands monitor FDA ANDA filings to ensure 45-day deadline is met; one missed 45-day window = no 30-month stay; (e) MANAGE SETTLEMENTS: post-Actavis, structure settlements to minimize antitrust exposure; avoid large, unexplained payments; (f) INJUNCTIVE RELIEF: if 30 months expire without resolution, seek preliminary injunction to prevent at-risk launch; GENERIC STRATEGY: (a) SELECT TARGETS CAREFULLY: choose drugs where patents are likely invalid or easily designed around; drugs with weak composition patents; patents near expiry; drugs with large revenue (high value of 180-day exclusivity); (b) FILE EARLY: the first filer gets 180-day exclusivity; filing early matters; (c) IPR STRATEGY: challenge patents at PTAB before filing ANDA or simultaneously; IPR provides faster and cheaper invalidity determination; but 1-year complaint service limitation creates timing issues; (d) DESIGN AROUND FORMULATION PATENTS: reformulate to avoid specific formulation patent claims; (e) SKINNY LABELING: omit patented indication from label; (f) 'AT RISK' ANALYSIS: financial modeling on at-risk launch vs. waiting; (g) COALITION BUILDING: multiple generics collaborate on IPR challenges to spread costs.