Moderna Announces Initiation of Phase 3 Study of Investigational mRNA Pandemic Influenza Vaccine Candidate

Phase 3 study is supported by the Coalition for Epidemic Preparedness Innovations to help strengthen global preparedness against a significant pandemic threat

CAMBRIDGE, MA / ACCESS Newswire / April 21, 2026 / Moderna, Inc. (NASDAQ:MRNA) today announced that the first participants in the U.S. and UK have been dosed in a Phase 3 study of the Company's investigational mRNA-based H5 pandemic influenza vaccine candidate, mRNA-1018. In December 2025, the Coalition for Epidemic Preparedness Innovations (CEPI) and Moderna announced that CEPI will invest up to $54.3 million to help advance mRNA-1018 to licensure.

"H5 influenza, or bird flu, remains a pandemic threat. The start of our Phase 3 trial for an H5 influenza vaccine marks a significant milestone in our ongoing efforts to strengthen global pandemic preparedness," said Stéphane Bancel, Chief Executive Officer of Moderna. "Our platform technology's efficiency and scalability are critical to supporting global health security and responding to potential future threats."

"The first-of-its-kind pivotal trial of an mRNA-based pandemic influenza vaccine underscores the potential of this technology to reshape how we confront emerging pathogens," said Dr. Richard Hatchett, CEO of CEPI. "If successful, these efforts could transform our ability to respond swiftly and equitably to one of the world's most enduring threats."

The Phase 3 study will evaluate the safety and immunogenicity of mRNA-1018 in healthy adults ages 18 years and older and is expected to enroll approximately 4,000 adults in the U.S. and UK. If successful, global regulatory submissions for mRNA-1018 will be further supported by positive data from the pivotal Phase 3 trial of Moderna's investigational seasonal influenza vaccine, mRNA-1010, which has been accepted for review in the U.S., the European Union, Canada and Australia.

"Although the current risk to the human population of avian influenza remains low, the virus continues to evolve and spread in birds and various animal hosts in the UK and elsewhere," said Dr. Richard Pebody, Director of Epidemic and Emerging Infections at the UK Health Security Agency (UKHSA). "UKHSA remains alert to the potential that this pathogen could adapt to spread from person to person, and will continue to monitor all available data. This important initiative to trial a new mRNA pandemic influenza vaccine is a key step towards further strengthening our ability to protect people against future influenza pandemics."

If licensed and in the event of an influenza pandemic, Moderna will allocate 20% of its H5 pandemic vaccine manufacturing capacity for timely supply to low- and middle-income countries at affordable pricing as part of its agreement with CEPI.

About Moderna

Moderna is a pioneer and leader in the field of mRNA medicine. Through the advancement of its technology platform, Moderna is reimagining how medicines are made to transform how we treat and prevent diseases. Since its founding, Moderna's mRNA platform has enabled the development of vaccines and therapeutics across infectious diseases, cancer, rare diseases and more.

With a global team and a unique culture, driven by the company's values and mindsets, Moderna's mission is to deliver the greatest possible impact to people through mRNA medicines. For more information about Moderna, please visit modernatx.com and connect with us on X, Facebook, Instagram, YouTube and LinkedIn.

Forward-Looking Statements

This press release contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995, as amended, including statements regarding: CEPI's investment to help advance Moderna's H5 pandemic influenza vaccine to licensure; the potential future licensure of mRNA-1018; the potential of mRNA to strengthen global pandemic preparedness; expected enrollment in the Phase 3 study of mRNA-1018; plans for potential global regulatory submissions for mRNA-1018 if the Phase 3 study is successful; ongoing regulatory review of mRNA-1010 in various jurisdictions; and Moderna's allocation of H5 pandemic vaccine manufacturing capacity. In some cases, forward-looking statements can be identified by terminology such as "will," "may," "should," "could," "expects," "intends," "plans," "aims," "anticipates," "believes," "estimates," "predicts," "potential," "continue," or the negative of these terms or other comparable terminology, although not all forward-looking statements contain these words. The forward-looking statements in this press release are neither promises nor guarantees, and you should not place undue reliance on these forward-looking statements because they involve known and unknown risks, uncertainties, and other factors, many of which are beyond Moderna's control and which could cause actual results to differ materially from those expressed or implied by these forward-looking statements. These risks, uncertainties, and other factors include, among others, those risks and uncertainties described under the heading "Risk Factors" in Moderna's Annual Report on Form 10-K for the fiscal year ended December 31, 2025, filed with the U.S. Securities and Exchange Commission (SEC), and in subsequent filings made by Moderna with the SEC, which are available on the SEC's website at www.sec.gov. Except as required by law, Moderna disclaims any intention or responsibility for updating or revising any forward-looking statements contained in this press release in the event of new information, future developments or otherwise. These forward-looking statements are based on Moderna's current expectations and speak only as of the date of this press release.

Moderna Contacts

Media:

Chris Ridley
Vice President, Global Head of Communications
+1 617-800-3651
Chris.Ridley@modernatx.com

Investors:

Lavina Talukdar
Senior Vice President & Head of Investor Relations
+1 617-209-5834
Lavina.Talukdar@modernatx.com

SOURCE: Moderna, Inc.