WATERTOWN, Mass.–(BUSINESS WIRE)–Enanta Pharmaceuticals, Inc. (NASDAQ: ENTA), a clinical-stage biotechnology company dedicated to creating novel, small molecule drugs for viral infections and immunological diseases, announced today that it has filed suit in the Unified Patent Court (UPC) of the European Union against Pfizer Inc. and certain of its subsidiaries (action number 35071/2025), seeking a determination of liability for use and infringement of European Patent No. EP 4 051 265 (the โ265 Patent) in the manufacture, use and sale of Pfizerโs COVID-19 antiviral, Paxlovidโข (nirmatrelvir tablets; ritonavir tablets). This enforcement action targets Pfizerโs activities in the 18 countries of the European Union that are presently participating in the UPC.
The European Patent Officeโs recent grant of the โ265 Patent to Enanta was published in the European Patent Bulletin today. The โ265 Patent is based on Enantaโs July 2020 patent application describing coronavirus protease inhibitors invented by Enanta scientists. The โ265 Patent is the European counterpart of U.S. Patent No. 11,358,953 (the โ953 Patent) involved in ongoing U.S. litigation between Enanta and Pfizer Inc.
Under UPC procedures, a hearing on the infringement action is expected to occur within the UPCโs published 12-month target, with the decision rendered within weeks thereafter. If the UPC determines there has been infringement, subsequent proceedings would be required to determine damages. All timelines remain subject to potential rights of appeal and other customary proceedings in European patent litigation.
About Enanta Pharmaceuticals, Inc.
Enanta is using its robust, chemistry-driven approach and drug discovery capabilities to become a leader in the discovery and development of small molecule drugs with an emphasis on indications in virology and immunology. Enantaโs clinical programs are currently focused on respiratory syncytial virus (RSV) and its earlier-stage immunology pipeline aims to develop treatments for inflammatory diseases by targeting key drivers of the type 2 immune response, including KIT and STAT6 inhibition.
Glecaprevir, a protease inhibitor discovered by Enanta, is part of one of the leading treatment regimens for curing hepatitis C virus (HCV) infection and is sold by AbbVie in numerous countries under the tradenames MAVYRETยฎ (U.S.) and MAVIRETยฎ (ex-U.S.) (glecaprevir/pibrentasvir). A portion of Enantaโs royalties from HCV products developed under its collaboration with AbbVie contribute ongoing funding to Enantaโs operations. Please visit www.enanta.com for more information.
Forward Looking Statements Disclaimer
This press release contains forward-looking statements, including statements with respect to Enantaโs filing in the UPC of a suit against Pfizer Inc. and certain of its subsidiaries seeking a determination of liability for use and infringement of Enantaโs patent and Enantaโs expectations with respect to any further action with respect to such proceedings. Statements that are not historical facts are based on managementโs current expectations, estimates, forecasts and projections about Enantaโs business and the industry in which it operates and managementโs beliefs and assumptions. The statements contained in this release are not guarantees of future performance and involve certain risks, uncertainties and assumptions, which are difficult to predict. Therefore, actual outcomes and results may differ materially from what is expressed in such forward-looking statements. Important factors and risks that may affect actual results include: Enanta is competing to develop intellectual property in areas of small-molecule drug development that are highly competitive; issued patents, including those covering one or more of its product candidates, could be found invalid or unenforceable if challenged in court and could be costly to defend and be a distraction for Enantaโs senior management and scientific personnel; intellectual property litigation may lead to unfavorable publicity that harms Enantaโs reputation and causes the market price of its common stock to decline; and other risk factors described or referred to in โRisk Factorsโ in Enantaโs Form 10-K for the fiscal year ended September 30, 2024 and other periodic reports filed more recently with the Securities and Exchange Commission. Enanta cautions investors not to place undue reliance on the forward-looking statements contained in this release. These statements speak only as of the date of this release, and Enanta undertakes no obligation to update or revise these statements, except as may be required by law.
Contacts
Media and Investor Contact
Jennifer Viera
617-744-3848
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