Novartis defeats drug-purchaser lawsuit over delay of Entresto generics

By Blake Brittain

Sept 23 (Reuters) - A federal judge in Manhattan ruled for Novartis NOVN.S on Wednesday against allegations that it misused one of its patents to maintain its exclusivity on its blockbuster heart-failure drug Entresto.

US District Judge Lewis Liman dismissed a lawsuit filed on behalf of drug purchasers who argued that Novartis improperly characterized the patent as covering Entresto in order to delay generics of the drug.

Attorneys for the drug purchasers and spokespeople for Novartis did not immediately respond to requests for comment on the ruling.

The New York-based Iron Workers Local 580 Insurance Fund filed the proposed class action lawsuit last year on behalf of Entresto buyers. It argued that purchasers paid inflated prices for the drug after Novartis improperly listed one of its patents in the US Food and Drug Administration's Orange Book – which lists patents covering drugs that the FDA has deemed safe and effective – to prevent generics from entering the market.

The lawsuit said the listing unlawfully delayed generic competition by at least six months during which Novartis earned more than $2 billion from US sales of the drug. Entresto constituted 14% of the company's sales last year, according to a company report.

Liman on Wednesday agreed with Novartis that the patent was properly listed in the Orange Book, rejecting the insurance fund's argument that the patent covered the drug's component ingredients but not the form in which they are combined in Entresto.

Entresto is Switzerland-based Novartis' best-selling drug, but its sales dropped by 42% to $1.31 billion in the first quarter of 2026 after its US patents expired and generics entered the market, according to a company report.

The case is Iron Workers Local 580 Insurance Fund v. Novartis Pharmaceuticals Corp, US District Court for the Southern District of New York, No. 1:25-cv-07230.

For Novartis: David Marriott of Latham & Watkins

For the drug purchasers: Joseph Meltzer of Kessler Topaz Meltzer & Check; James Cecchi of Carella Byrne Cecchi Brody & Agnello; Thomas Sobol of Hagens Berman Sobol Shapiro; Dena Sharp of Girard Sharp

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