Genentech Inc v. Sun Pharmaceutical Industries Ltd

I. Executive Summary and Procedural Information

• Parties & Counsel:
  • Plaintiffs: Genentech, Inc. (Delaware) and Hoffmann-La Roche Inc. (New Jersey)
  • Defendants: Natco Pharma Limited (India); Sun Pharmaceutical Industries Ltd. (India); Sun Pharmaceutical Industries, Inc. (Delaware); Zydus Lifesciences Global FZE (United Arab Emirates); Zydus Lifesciences Ltd. (India); and Zydus Pharmaceuticals (USA) Inc. (New Jersey)
  • Plaintiff’s Counsel: Robinson Miller LLC; Groombridge, Wu, Baughman & Stone LLP
• Case Identification: 2:25-cv-17100, D.N.J., 02/12/2026
• Venue Allegations: Plaintiffs allege venue is proper in the District of New Jersey because the U.S.-based defendants (Sun Inc. and Zydus Inc.) reside in New Jersey and have committed acts of infringement there. For the foreign defendants, Plaintiffs allege venue is proper in any district where they are subject to personal jurisdiction.
• Core Dispute: Plaintiffs allege that Defendants' Abbreviated New Drug Applications (ANDAs) to market generic versions of the spinal muscular atrophy drug EVRYSDI® (risdiplam) infringe a patent covering specific weight-based dosing methods for the drug.
• Technical Context: The dispute is in the field of pharmaceutical treatments for spinal muscular atrophy (SMA), a neurodegenerative disease, focusing on the specific method of administering an oral therapy based on patient body weight.
• Key Procedural History: The litigation was triggered by Defendants Natco/Sun and Zydus each filing an ANDA containing a Paragraph IV Certification, asserting that the patent-in-suit is invalid, unenforceable, or will not be infringed by their proposed generic products.

Case Timeline

II. Technology and Patent(s)-in-Suit Analysis

U.S. Patent No. 12,350,273 - "Treatment of SMA"

• Patent Identification: U.S. Patent No. 12,350,273, "Treatment of SMA", issued July 8, 2025 (the "'273 Patent").

The Invention Explained

• Problem Addressed: The patent describes spinal muscular atrophy (SMA) as a severe neurodegenerative disorder with no approved oral treatment that provides stabilization or improvement of motor function '273 Patent, col. 2:31-34 The background highlights the need for an effective oral therapy with limited side effects '273 Patent, col. 2:42-48
• The Patented Solution: The invention provides a method for treating SMA by orally administering a specific compound, risdiplam (identified as formula (I)), according to dosing regimens tailored to the patient's body weight '273 Patent, abstract The patent specification discloses that clinical studies surprisingly found that an optimal dose would be 0.25 mg/kg for patients weighing less than 20 kg and a fixed 5 mg dose for patients weighing 20 kg or more '273 Patent, col. 2:60-col. 3:4
• Technical Importance: The invention claims to provide a specific, weight-based oral dosing regimen that improves outcomes for SMA patients, a group for whom effective oral treatments were previously unavailable '273 Patent, col. 2:31-48

Key Claims at a Glance

• The complaint asserts independent claims 1 and 8 '273 Patent, col. 56:1-8 '273 Patent, col. 56:62-col. 57:9 Compl. ¶¶75, 85
• Claim 1 Elements:
  • A method of treating spinal muscular atrophy (SMA) in a human patient in need thereof,
  • comprising administering to the patient a pharmaceutical composition comprising a compound of formula (I),
  • at a once daily oral dose of 5 mg,
  • wherein the patient has a body weight of more than or equal to 20 kg.
• Claim 8 Elements:
  • A method of treating spinal muscular atrophy (SMA) in a human patient in need thereof,
  • comprising administering to the patient a pharmaceutical composition comprising a compound of formula (I),
  • at a once daily oral dose of 0.25 mg/kg,
  • wherein the patient has a body weight of less than 20 kg.
• The complaint does not explicitly reserve the right to assert dependent claims but references infringement of "one or more claims" Compl., prayer A

III. The Accused Instrumentality

Product Identification

• The accused instrumentalities are the generic risdiplam oral solution products for which Defendants have sought FDA approval via their respective ANDAs (the "Natco ANDA Product" and the "Zydus ANDA Product") Compl. ¶¶1, 47, 58

Functionality and Market Context

• The complaint alleges that Defendants' ANDA products are generic versions of Plaintiffs' EVRYSDI® product, which is an oral therapy for SMA Compl. ¶1 The infringement allegation is based on the act of filing an ANDA to market a drug for a patented use prior to patent expiration Compl. ¶¶56-57, 66-67
• The functionality relevant to the infringement allegations is contained in the proposed product labeling. The complaint alleges that the Defendants' product labels will "essentially copy" the EVRYSDI® label Compl. ¶¶76, 86 The EVRYSDI® label, a portion of which is reproduced in the complaint, instructs administration "orally once daily," with the recommended dosage determined by body weight Compl. ¶45 The complaint includes a table from the EVRYSDI® label that specifies a 5 mg dose for patients weighing 20 kg or more and a 0.25 mg/kg dose for patients between 2 years of age and older weighing less than 20 kg Compl. p. 12, Table 1

IV. Analysis of Infringement Allegations

’273 Patent Infringement Allegations

Identified Points of Contention

• Instructional Scope: A central question in this ANDA litigation will be whether the Defendants' proposed product labels, which the complaint alleges will copy the EVRYSDI® label, will instruct, recommend, or encourage physicians and patients to administer the generic product according to the specific weight-based dosing regimens recited in claims 1 and 8. The complaint alleges that the Defendants have not contested infringement in their notice letters, which may suggest this point is not in dispute Compl. ¶¶75, 85
• Technical Match: The complaint's infringement theory relies on a direct mapping between the EVRYSDI® dosing table and the limitations of claims 1 and 8 Compl. p. 12, Table 1 The analysis may raise the question of whether there are any non-infringing uses described on the label, though the complaint alleges the product is not a staple article of commerce and has no substantial non-infringing uses Compl. ¶¶77, 87

V. Key Claim Terms for Construction

• The Term: "treating spinal muscular atrophy (SMA)"
• Context and Importance: This term appears in the preamble of both asserted independent claims. Its construction is important because it defines the purpose and scope of the claimed method. A dispute could arise over whether this preamble term is a mere statement of intended use or if it imposes a positive limitation on the claim, potentially requiring the administration to achieve a therapeutic effect.
• Intrinsic Evidence for Interpretation:
  • Evidence for a Broader Interpretation: The body of the claims recites concrete, physical steps of administration based on dosage and patient weight. This may support an interpretation that the preamble merely states the context for these steps, with infringement occurring so long as the steps are performed for the stated purpose, regardless of outcome.
  • Evidence for a Narrower Interpretation: The specification provides a detailed definition of "treating spinal muscular atrophy," listing numerous beneficial effects, such as "reduction or amelioration of the severity of SMA," "increase of the survival of a subject," and an "increase in motor function" ’273 Patent, col. 5:46-col. 6:4 A defendant could argue that this language requires the method to be effective, potentially raising questions of efficacy not typically central to ANDA cases focused on bioequivalence.

VI. Other Allegations

Indirect Infringement

• The core of the infringement action is based on induced infringement under 35 U.S.C. § 271(e)(2)(A), which defines the filing of an ANDA for a patented use as a statutory act of infringement Compl. ¶¶56, 66 The complaint alleges that upon approval, Defendants will induce infringement by physicians and patients because the product labels "instructs, recommends, encourages, and/or suggests" performance of the patented method Compl. ¶¶76, 86

Willful Infringement

• The complaint does not include a formal count for willful infringement. However, it alleges that the Defendants' statements regarding invalidity are "devoid of a good faith basis in either the facts or the law," which may be used to support a request for enhanced damages or attorneys' fees under 35 U.S.C. § 285 if infringement is found Compl. ¶¶82, 92

VII. Analyst’s Conclusion: Key Questions for the Case

• A central issue appears to be one of validity, as suggested by the Defendants' Paragraph IV certifications and the complaint's allegation that infringement itself is uncontested. The case will likely focus on whether the claimed weight-based dosing regimens were obvious or anticipated by the prior art at the time of the invention.
• A secondary question, though seemingly straightforward based on the complaint, is one of instructional scope: does the Defendants' proposed labeling, as a whole, unambiguously instruct and encourage medical professionals to administer the generic drug in a manner that satisfies all limitations of the asserted method claims, thereby inducing infringement?
• Finally, a potential claim construction issue may arise regarding the meaning of "treating": does the preamble term require a demonstrated therapeutic outcome for infringement, or is it sufficient that the drug is administered for the purpose of treating SMA according to the claimed dosing steps?